diff options
Diffstat (limited to 'net/can')
| -rw-r--r-- | net/can/Kconfig | 73 | ||||
| -rw-r--r-- | net/can/Makefile | 22 | ||||
| -rw-r--r-- | net/can/af_can.c | 917 | ||||
| -rw-r--r-- | net/can/af_can.h | 103 | ||||
| -rw-r--r-- | net/can/bcm.c | 1787 | ||||
| -rw-r--r-- | net/can/gw.c | 1336 | ||||
| -rw-r--r-- | net/can/isotp.c | 1737 | ||||
| -rw-r--r-- | net/can/j1939/Kconfig | 15 | ||||
| -rw-r--r-- | net/can/j1939/Makefile | 10 | ||||
| -rw-r--r-- | net/can/j1939/address-claim.c | 270 | ||||
| -rw-r--r-- | net/can/j1939/bus.c | 333 | ||||
| -rw-r--r-- | net/can/j1939/j1939-priv.h | 343 | ||||
| -rw-r--r-- | net/can/j1939/main.c | 429 | ||||
| -rw-r--r-- | net/can/j1939/socket.c | 1325 | ||||
| -rw-r--r-- | net/can/j1939/transport.c | 2206 | ||||
| -rw-r--r-- | net/can/proc.c | 498 | ||||
| -rw-r--r-- | net/can/raw.c | 1024 |
17 files changed, 12428 insertions, 0 deletions
diff --git a/net/can/Kconfig b/net/can/Kconfig new file mode 100644 index 000000000..cb56be8e3 --- /dev/null +++ b/net/can/Kconfig @@ -0,0 +1,73 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Controller Area Network (CAN) network layer core configuration +# + +menuconfig CAN + tristate "CAN bus subsystem support" + help + Controller Area Network (CAN) is a slow (up to 1Mbit/s) serial + communications protocol. Development of the CAN bus started in + 1983 at Robert Bosch GmbH, and the protocol was officially + released in 1986. The CAN bus was originally mainly for automotive, + but is now widely used in marine (NMEA2000), industrial, and medical + applications. More information on the CAN network protocol family + PF_CAN is contained in <Documentation/networking/can.rst>. + + If you want CAN support you should say Y here and also to the + specific driver for your controller(s) under the Network device + support section. + +if CAN + +config CAN_RAW + tristate "Raw CAN Protocol (raw access with CAN-ID filtering)" + default y + help + The raw CAN protocol option offers access to the CAN bus via + the BSD socket API. You probably want to use the raw socket in + most cases where no higher level protocol is being used. The raw + socket has several filter options e.g. ID masking / error frames. + To receive/send raw CAN messages, use AF_CAN with protocol CAN_RAW. + +config CAN_BCM + tristate "Broadcast Manager CAN Protocol (with content filtering)" + default y + help + The Broadcast Manager offers content filtering, timeout monitoring, + sending of RTR frames, and cyclic CAN messages without permanent user + interaction. The BCM can be 'programmed' via the BSD socket API and + informs you on demand e.g. only on content updates / timeouts. + You probably want to use the bcm socket in most cases where cyclic + CAN messages are used on the bus (e.g. in automotive environments). + To use the Broadcast Manager, use AF_CAN with protocol CAN_BCM. + +config CAN_GW + tristate "CAN Gateway/Router (with netlink configuration)" + default y + help + The CAN Gateway/Router is used to route (and modify) CAN frames. + It is based on the PF_CAN core infrastructure for msg filtering and + msg sending and can optionally modify routed CAN frames on the fly. + CAN frames can be routed between CAN network interfaces (one hop). + They can be modified with AND/OR/XOR/SET operations as configured + by the netlink configuration interface known e.g. from iptables. + +source "net/can/j1939/Kconfig" + +config CAN_ISOTP + tristate "ISO 15765-2:2016 CAN transport protocol" + help + CAN Transport Protocols offer support for segmented Point-to-Point + communication between CAN nodes via two defined CAN Identifiers. + As CAN frames can only transport a small amount of data bytes + (max. 8 bytes for 'classic' CAN and max. 64 bytes for CAN FD) this + segmentation is needed to transport longer Protocol Data Units (PDU) + as needed e.g. for vehicle diagnosis (UDS, ISO 14229) or IP-over-CAN + traffic. + This protocol driver implements data transfers according to + ISO 15765-2:2016 for 'classic' CAN and CAN FD frame types. + If you want to perform automotive vehicle diagnostic services (UDS), + say 'y'. + +endif diff --git a/net/can/Makefile b/net/can/Makefile new file mode 100644 index 000000000..58f2c31c1 --- /dev/null +++ b/net/can/Makefile @@ -0,0 +1,22 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the Linux Controller Area Network core. +# + +obj-$(CONFIG_CAN) += can.o +can-y := af_can.o +can-$(CONFIG_PROC_FS) += proc.o + +obj-$(CONFIG_CAN_RAW) += can-raw.o +can-raw-y := raw.o + +obj-$(CONFIG_CAN_BCM) += can-bcm.o +can-bcm-y := bcm.o + +obj-$(CONFIG_CAN_GW) += can-gw.o +can-gw-y := gw.o + +obj-$(CONFIG_CAN_J1939) += j1939/ + +obj-$(CONFIG_CAN_ISOTP) += can-isotp.o +can-isotp-y := isotp.o diff --git a/net/can/af_can.c b/net/can/af_can.c new file mode 100644 index 000000000..7343fd487 --- /dev/null +++ b/net/can/af_can.c @@ -0,0 +1,917 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* af_can.c - Protocol family CAN core module + * (used by different CAN protocol modules) + * + * Copyright (c) 2002-2017 Volkswagen Group Electronic Research + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Volkswagen nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * Alternatively, provided that this notice is retained in full, this + * software may be distributed under the terms of the GNU General + * Public License ("GPL") version 2, in which case the provisions of the + * GPL apply INSTEAD OF those given above. + * + * The provided data structures and external interfaces from this code + * are not restricted to be used by modules with a GPL compatible license. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + */ + +#include <linux/module.h> +#include <linux/stddef.h> +#include <linux/init.h> +#include <linux/kmod.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/spinlock.h> +#include <linux/rcupdate.h> +#include <linux/uaccess.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/socket.h> +#include <linux/if_ether.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/can.h> +#include <linux/can/core.h> +#include <linux/can/skb.h> +#include <linux/can/can-ml.h> +#include <linux/ratelimit.h> +#include <net/net_namespace.h> +#include <net/sock.h> + +#include "af_can.h" + +MODULE_DESCRIPTION("Controller Area Network PF_CAN core"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, " + "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); + +MODULE_ALIAS_NETPROTO(PF_CAN); + +static int stats_timer __read_mostly = 1; +module_param(stats_timer, int, 0444); +MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)"); + +static struct kmem_cache *rcv_cache __read_mostly; + +/* table of registered CAN protocols */ +static const struct can_proto __rcu *proto_tab[CAN_NPROTO] __read_mostly; +static DEFINE_MUTEX(proto_tab_lock); + +static atomic_t skbcounter = ATOMIC_INIT(0); + +/* af_can socket functions */ + +void can_sock_destruct(struct sock *sk) +{ + skb_queue_purge(&sk->sk_receive_queue); + skb_queue_purge(&sk->sk_error_queue); +} +EXPORT_SYMBOL(can_sock_destruct); + +static const struct can_proto *can_get_proto(int protocol) +{ + const struct can_proto *cp; + + rcu_read_lock(); + cp = rcu_dereference(proto_tab[protocol]); + if (cp && !try_module_get(cp->prot->owner)) + cp = NULL; + rcu_read_unlock(); + + return cp; +} + +static inline void can_put_proto(const struct can_proto *cp) +{ + module_put(cp->prot->owner); +} + +static int can_create(struct net *net, struct socket *sock, int protocol, + int kern) +{ + struct sock *sk; + const struct can_proto *cp; + int err = 0; + + sock->state = SS_UNCONNECTED; + + if (protocol < 0 || protocol >= CAN_NPROTO) + return -EINVAL; + + cp = can_get_proto(protocol); + +#ifdef CONFIG_MODULES + if (!cp) { + /* try to load protocol module if kernel is modular */ + + err = request_module("can-proto-%d", protocol); + + /* In case of error we only print a message but don't + * return the error code immediately. Below we will + * return -EPROTONOSUPPORT + */ + if (err) + pr_err_ratelimited("can: request_module (can-proto-%d) failed.\n", + protocol); + + cp = can_get_proto(protocol); + } +#endif + + /* check for available protocol and correct usage */ + + if (!cp) + return -EPROTONOSUPPORT; + + if (cp->type != sock->type) { + err = -EPROTOTYPE; + goto errout; + } + + sock->ops = cp->ops; + + sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot, kern); + if (!sk) { + err = -ENOMEM; + goto errout; + } + + sock_init_data(sock, sk); + sk->sk_destruct = can_sock_destruct; + + if (sk->sk_prot->init) + err = sk->sk_prot->init(sk); + + if (err) { + /* release sk on errors */ + sock_orphan(sk); + sock_put(sk); + } + + errout: + can_put_proto(cp); + return err; +} + +/* af_can tx path */ + +/** + * can_send - transmit a CAN frame (optional with local loopback) + * @skb: pointer to socket buffer with CAN frame in data section + * @loop: loopback for listeners on local CAN sockets (recommended default!) + * + * Due to the loopback this routine must not be called from hardirq context. + * + * Return: + * 0 on success + * -ENETDOWN when the selected interface is down + * -ENOBUFS on full driver queue (see net_xmit_errno()) + * -ENOMEM when local loopback failed at calling skb_clone() + * -EPERM when trying to send on a non-CAN interface + * -EMSGSIZE CAN frame size is bigger than CAN interface MTU + * -EINVAL when the skb->data does not contain a valid CAN frame + */ +int can_send(struct sk_buff *skb, int loop) +{ + struct sk_buff *newskb = NULL; + struct can_pkg_stats *pkg_stats = dev_net(skb->dev)->can.pkg_stats; + int err = -EINVAL; + + if (can_is_canxl_skb(skb)) { + skb->protocol = htons(ETH_P_CANXL); + } else if (can_is_can_skb(skb)) { + skb->protocol = htons(ETH_P_CAN); + } else if (can_is_canfd_skb(skb)) { + struct canfd_frame *cfd = (struct canfd_frame *)skb->data; + + skb->protocol = htons(ETH_P_CANFD); + + /* set CAN FD flag for CAN FD frames by default */ + cfd->flags |= CANFD_FDF; + } else { + goto inval_skb; + } + + /* Make sure the CAN frame can pass the selected CAN netdevice. */ + if (unlikely(skb->len > skb->dev->mtu)) { + err = -EMSGSIZE; + goto inval_skb; + } + + if (unlikely(skb->dev->type != ARPHRD_CAN)) { + err = -EPERM; + goto inval_skb; + } + + if (unlikely(!(skb->dev->flags & IFF_UP))) { + err = -ENETDOWN; + goto inval_skb; + } + + skb->ip_summed = CHECKSUM_UNNECESSARY; + + skb_reset_mac_header(skb); + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + + if (loop) { + /* local loopback of sent CAN frames */ + + /* indication for the CAN driver: do loopback */ + skb->pkt_type = PACKET_LOOPBACK; + + /* The reference to the originating sock may be required + * by the receiving socket to check whether the frame is + * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS + * Therefore we have to ensure that skb->sk remains the + * reference to the originating sock by restoring skb->sk + * after each skb_clone() or skb_orphan() usage. + */ + + if (!(skb->dev->flags & IFF_ECHO)) { + /* If the interface is not capable to do loopback + * itself, we do it here. + */ + newskb = skb_clone(skb, GFP_ATOMIC); + if (!newskb) { + kfree_skb(skb); + return -ENOMEM; + } + + can_skb_set_owner(newskb, skb->sk); + newskb->ip_summed = CHECKSUM_UNNECESSARY; + newskb->pkt_type = PACKET_BROADCAST; + } + } else { + /* indication for the CAN driver: no loopback required */ + skb->pkt_type = PACKET_HOST; + } + + /* send to netdevice */ + err = dev_queue_xmit(skb); + if (err > 0) + err = net_xmit_errno(err); + + if (err) { + kfree_skb(newskb); + return err; + } + + if (newskb) + netif_rx(newskb); + + /* update statistics */ + pkg_stats->tx_frames++; + pkg_stats->tx_frames_delta++; + + return 0; + +inval_skb: + kfree_skb(skb); + return err; +} +EXPORT_SYMBOL(can_send); + +/* af_can rx path */ + +static struct can_dev_rcv_lists *can_dev_rcv_lists_find(struct net *net, + struct net_device *dev) +{ + if (dev) { + struct can_ml_priv *can_ml = can_get_ml_priv(dev); + return &can_ml->dev_rcv_lists; + } else { + return net->can.rx_alldev_list; + } +} + +/** + * effhash - hash function for 29 bit CAN identifier reduction + * @can_id: 29 bit CAN identifier + * + * Description: + * To reduce the linear traversal in one linked list of _single_ EFF CAN + * frame subscriptions the 29 bit identifier is mapped to 10 bits. + * (see CAN_EFF_RCV_HASH_BITS definition) + * + * Return: + * Hash value from 0x000 - 0x3FF ( enforced by CAN_EFF_RCV_HASH_BITS mask ) + */ +static unsigned int effhash(canid_t can_id) +{ + unsigned int hash; + + hash = can_id; + hash ^= can_id >> CAN_EFF_RCV_HASH_BITS; + hash ^= can_id >> (2 * CAN_EFF_RCV_HASH_BITS); + + return hash & ((1 << CAN_EFF_RCV_HASH_BITS) - 1); +} + +/** + * can_rcv_list_find - determine optimal filterlist inside device filter struct + * @can_id: pointer to CAN identifier of a given can_filter + * @mask: pointer to CAN mask of a given can_filter + * @dev_rcv_lists: pointer to the device filter struct + * + * Description: + * Returns the optimal filterlist to reduce the filter handling in the + * receive path. This function is called by service functions that need + * to register or unregister a can_filter in the filter lists. + * + * A filter matches in general, when + * + * <received_can_id> & mask == can_id & mask + * + * so every bit set in the mask (even CAN_EFF_FLAG, CAN_RTR_FLAG) describe + * relevant bits for the filter. + * + * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can + * filter for error messages (CAN_ERR_FLAG bit set in mask). For error msg + * frames there is a special filterlist and a special rx path filter handling. + * + * Return: + * Pointer to optimal filterlist for the given can_id/mask pair. + * Consistency checked mask. + * Reduced can_id to have a preprocessed filter compare value. + */ +static struct hlist_head *can_rcv_list_find(canid_t *can_id, canid_t *mask, + struct can_dev_rcv_lists *dev_rcv_lists) +{ + canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking */ + + /* filter for error message frames in extra filterlist */ + if (*mask & CAN_ERR_FLAG) { + /* clear CAN_ERR_FLAG in filter entry */ + *mask &= CAN_ERR_MASK; + return &dev_rcv_lists->rx[RX_ERR]; + } + + /* with cleared CAN_ERR_FLAG we have a simple mask/value filterpair */ + +#define CAN_EFF_RTR_FLAGS (CAN_EFF_FLAG | CAN_RTR_FLAG) + + /* ensure valid values in can_mask for 'SFF only' frame filtering */ + if ((*mask & CAN_EFF_FLAG) && !(*can_id & CAN_EFF_FLAG)) + *mask &= (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS); + + /* reduce condition testing at receive time */ + *can_id &= *mask; + + /* inverse can_id/can_mask filter */ + if (inv) + return &dev_rcv_lists->rx[RX_INV]; + + /* mask == 0 => no condition testing at receive time */ + if (!(*mask)) + return &dev_rcv_lists->rx[RX_ALL]; + + /* extra filterlists for the subscription of a single non-RTR can_id */ + if (((*mask & CAN_EFF_RTR_FLAGS) == CAN_EFF_RTR_FLAGS) && + !(*can_id & CAN_RTR_FLAG)) { + if (*can_id & CAN_EFF_FLAG) { + if (*mask == (CAN_EFF_MASK | CAN_EFF_RTR_FLAGS)) + return &dev_rcv_lists->rx_eff[effhash(*can_id)]; + } else { + if (*mask == (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS)) + return &dev_rcv_lists->rx_sff[*can_id]; + } + } + + /* default: filter via can_id/can_mask */ + return &dev_rcv_lists->rx[RX_FIL]; +} + +/** + * can_rx_register - subscribe CAN frames from a specific interface + * @net: the applicable net namespace + * @dev: pointer to netdevice (NULL => subscribe from 'all' CAN devices list) + * @can_id: CAN identifier (see description) + * @mask: CAN mask (see description) + * @func: callback function on filter match + * @data: returned parameter for callback function + * @ident: string for calling module identification + * @sk: socket pointer (might be NULL) + * + * Description: + * Invokes the callback function with the received sk_buff and the given + * parameter 'data' on a matching receive filter. A filter matches, when + * + * <received_can_id> & mask == can_id & mask + * + * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can + * filter for error message frames (CAN_ERR_FLAG bit set in mask). + * + * The provided pointer to the sk_buff is guaranteed to be valid as long as + * the callback function is running. The callback function must *not* free + * the given sk_buff while processing it's task. When the given sk_buff is + * needed after the end of the callback function it must be cloned inside + * the callback function with skb_clone(). + * + * Return: + * 0 on success + * -ENOMEM on missing cache mem to create subscription entry + * -ENODEV unknown device + */ +int can_rx_register(struct net *net, struct net_device *dev, canid_t can_id, + canid_t mask, void (*func)(struct sk_buff *, void *), + void *data, char *ident, struct sock *sk) +{ + struct receiver *rcv; + struct hlist_head *rcv_list; + struct can_dev_rcv_lists *dev_rcv_lists; + struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats; + + /* insert new receiver (dev,canid,mask) -> (func,data) */ + + if (dev && (dev->type != ARPHRD_CAN || !can_get_ml_priv(dev))) + return -ENODEV; + + if (dev && !net_eq(net, dev_net(dev))) + return -ENODEV; + + rcv = kmem_cache_alloc(rcv_cache, GFP_KERNEL); + if (!rcv) + return -ENOMEM; + + spin_lock_bh(&net->can.rcvlists_lock); + + dev_rcv_lists = can_dev_rcv_lists_find(net, dev); + rcv_list = can_rcv_list_find(&can_id, &mask, dev_rcv_lists); + + rcv->can_id = can_id; + rcv->mask = mask; + rcv->matches = 0; + rcv->func = func; + rcv->data = data; + rcv->ident = ident; + rcv->sk = sk; + + hlist_add_head_rcu(&rcv->list, rcv_list); + dev_rcv_lists->entries++; + + rcv_lists_stats->rcv_entries++; + rcv_lists_stats->rcv_entries_max = max(rcv_lists_stats->rcv_entries_max, + rcv_lists_stats->rcv_entries); + spin_unlock_bh(&net->can.rcvlists_lock); + + return 0; +} +EXPORT_SYMBOL(can_rx_register); + +/* can_rx_delete_receiver - rcu callback for single receiver entry removal */ +static void can_rx_delete_receiver(struct rcu_head *rp) +{ + struct receiver *rcv = container_of(rp, struct receiver, rcu); + struct sock *sk = rcv->sk; + + kmem_cache_free(rcv_cache, rcv); + if (sk) + sock_put(sk); +} + +/** + * can_rx_unregister - unsubscribe CAN frames from a specific interface + * @net: the applicable net namespace + * @dev: pointer to netdevice (NULL => unsubscribe from 'all' CAN devices list) + * @can_id: CAN identifier + * @mask: CAN mask + * @func: callback function on filter match + * @data: returned parameter for callback function + * + * Description: + * Removes subscription entry depending on given (subscription) values. + */ +void can_rx_unregister(struct net *net, struct net_device *dev, canid_t can_id, + canid_t mask, void (*func)(struct sk_buff *, void *), + void *data) +{ + struct receiver *rcv = NULL; + struct hlist_head *rcv_list; + struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats; + struct can_dev_rcv_lists *dev_rcv_lists; + + if (dev && dev->type != ARPHRD_CAN) + return; + + if (dev && !net_eq(net, dev_net(dev))) + return; + + spin_lock_bh(&net->can.rcvlists_lock); + + dev_rcv_lists = can_dev_rcv_lists_find(net, dev); + rcv_list = can_rcv_list_find(&can_id, &mask, dev_rcv_lists); + + /* Search the receiver list for the item to delete. This should + * exist, since no receiver may be unregistered that hasn't + * been registered before. + */ + hlist_for_each_entry_rcu(rcv, rcv_list, list) { + if (rcv->can_id == can_id && rcv->mask == mask && + rcv->func == func && rcv->data == data) + break; + } + + /* Check for bugs in CAN protocol implementations using af_can.c: + * 'rcv' will be NULL if no matching list item was found for removal. + * As this case may potentially happen when closing a socket while + * the notifier for removing the CAN netdev is running we just print + * a warning here. + */ + if (!rcv) { + pr_warn("can: receive list entry not found for dev %s, id %03X, mask %03X\n", + DNAME(dev), can_id, mask); + goto out; + } + + hlist_del_rcu(&rcv->list); + dev_rcv_lists->entries--; + + if (rcv_lists_stats->rcv_entries > 0) + rcv_lists_stats->rcv_entries--; + + out: + spin_unlock_bh(&net->can.rcvlists_lock); + + /* schedule the receiver item for deletion */ + if (rcv) { + if (rcv->sk) + sock_hold(rcv->sk); + call_rcu(&rcv->rcu, can_rx_delete_receiver); + } +} +EXPORT_SYMBOL(can_rx_unregister); + +static inline void deliver(struct sk_buff *skb, struct receiver *rcv) +{ + rcv->func(skb, rcv->data); + rcv->matches++; +} + +static int can_rcv_filter(struct can_dev_rcv_lists *dev_rcv_lists, struct sk_buff *skb) +{ + struct receiver *rcv; + int matches = 0; + struct can_frame *cf = (struct can_frame *)skb->data; + canid_t can_id = cf->can_id; + + if (dev_rcv_lists->entries == 0) + return 0; + + if (can_id & CAN_ERR_FLAG) { + /* check for error message frame entries only */ + hlist_for_each_entry_rcu(rcv, &dev_rcv_lists->rx[RX_ERR], list) { + if (can_id & rcv->mask) { + deliver(skb, rcv); + matches++; + } + } + return matches; + } + + /* check for unfiltered entries */ + hlist_for_each_entry_rcu(rcv, &dev_rcv_lists->rx[RX_ALL], list) { + deliver(skb, rcv); + matches++; + } + + /* check for can_id/mask entries */ + hlist_for_each_entry_rcu(rcv, &dev_rcv_lists->rx[RX_FIL], list) { + if ((can_id & rcv->mask) == rcv->can_id) { + deliver(skb, rcv); + matches++; + } + } + + /* check for inverted can_id/mask entries */ + hlist_for_each_entry_rcu(rcv, &dev_rcv_lists->rx[RX_INV], list) { + if ((can_id & rcv->mask) != rcv->can_id) { + deliver(skb, rcv); + matches++; + } + } + + /* check filterlists for single non-RTR can_ids */ + if (can_id & CAN_RTR_FLAG) + return matches; + + if (can_id & CAN_EFF_FLAG) { + hlist_for_each_entry_rcu(rcv, &dev_rcv_lists->rx_eff[effhash(can_id)], list) { + if (rcv->can_id == can_id) { + deliver(skb, rcv); + matches++; + } + } + } else { + can_id &= CAN_SFF_MASK; + hlist_for_each_entry_rcu(rcv, &dev_rcv_lists->rx_sff[can_id], list) { + deliver(skb, rcv); + matches++; + } + } + + return matches; +} + +static void can_receive(struct sk_buff *skb, struct net_device *dev) +{ + struct can_dev_rcv_lists *dev_rcv_lists; + struct net *net = dev_net(dev); + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + int matches; + + /* update statistics */ + pkg_stats->rx_frames++; + pkg_stats->rx_frames_delta++; + + /* create non-zero unique skb identifier together with *skb */ + while (!(can_skb_prv(skb)->skbcnt)) + can_skb_prv(skb)->skbcnt = atomic_inc_return(&skbcounter); + + rcu_read_lock(); + + /* deliver the packet to sockets listening on all devices */ + matches = can_rcv_filter(net->can.rx_alldev_list, skb); + + /* find receive list for this device */ + dev_rcv_lists = can_dev_rcv_lists_find(net, dev); + matches += can_rcv_filter(dev_rcv_lists, skb); + + rcu_read_unlock(); + + /* consume the skbuff allocated by the netdevice driver */ + consume_skb(skb); + + if (matches > 0) { + pkg_stats->matches++; + pkg_stats->matches_delta++; + } +} + +static int can_rcv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev) +{ + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_can_skb(skb))) { + pr_warn_once("PF_CAN: dropped non conform CAN skbuff: dev type %d, len %d\n", + dev->type, skb->len); + + kfree_skb(skb); + return NET_RX_DROP; + } + + can_receive(skb, dev); + return NET_RX_SUCCESS; +} + +static int canfd_rcv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev) +{ + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_canfd_skb(skb))) { + pr_warn_once("PF_CAN: dropped non conform CAN FD skbuff: dev type %d, len %d\n", + dev->type, skb->len); + + kfree_skb(skb); + return NET_RX_DROP; + } + + can_receive(skb, dev); + return NET_RX_SUCCESS; +} + +static int canxl_rcv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev) +{ + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_canxl_skb(skb))) { + pr_warn_once("PF_CAN: dropped non conform CAN XL skbuff: dev type %d, len %d\n", + dev->type, skb->len); + + kfree_skb(skb); + return NET_RX_DROP; + } + + can_receive(skb, dev); + return NET_RX_SUCCESS; +} + +/* af_can protocol functions */ + +/** + * can_proto_register - register CAN transport protocol + * @cp: pointer to CAN protocol structure + * + * Return: + * 0 on success + * -EINVAL invalid (out of range) protocol number + * -EBUSY protocol already in use + * -ENOBUF if proto_register() fails + */ +int can_proto_register(const struct can_proto *cp) +{ + int proto = cp->protocol; + int err = 0; + + if (proto < 0 || proto >= CAN_NPROTO) { + pr_err("can: protocol number %d out of range\n", proto); + return -EINVAL; + } + + err = proto_register(cp->prot, 0); + if (err < 0) + return err; + + mutex_lock(&proto_tab_lock); + + if (rcu_access_pointer(proto_tab[proto])) { + pr_err("can: protocol %d already registered\n", proto); + err = -EBUSY; + } else { + RCU_INIT_POINTER(proto_tab[proto], cp); + } + + mutex_unlock(&proto_tab_lock); + + if (err < 0) + proto_unregister(cp->prot); + + return err; +} +EXPORT_SYMBOL(can_proto_register); + +/** + * can_proto_unregister - unregister CAN transport protocol + * @cp: pointer to CAN protocol structure + */ +void can_proto_unregister(const struct can_proto *cp) +{ + int proto = cp->protocol; + + mutex_lock(&proto_tab_lock); + BUG_ON(rcu_access_pointer(proto_tab[proto]) != cp); + RCU_INIT_POINTER(proto_tab[proto], NULL); + mutex_unlock(&proto_tab_lock); + + synchronize_rcu(); + + proto_unregister(cp->prot); +} +EXPORT_SYMBOL(can_proto_unregister); + +static int can_pernet_init(struct net *net) +{ + spin_lock_init(&net->can.rcvlists_lock); + net->can.rx_alldev_list = + kzalloc(sizeof(*net->can.rx_alldev_list), GFP_KERNEL); + if (!net->can.rx_alldev_list) + goto out; + net->can.pkg_stats = kzalloc(sizeof(*net->can.pkg_stats), GFP_KERNEL); + if (!net->can.pkg_stats) + goto out_free_rx_alldev_list; + net->can.rcv_lists_stats = kzalloc(sizeof(*net->can.rcv_lists_stats), GFP_KERNEL); + if (!net->can.rcv_lists_stats) + goto out_free_pkg_stats; + + if (IS_ENABLED(CONFIG_PROC_FS)) { + /* the statistics are updated every second (timer triggered) */ + if (stats_timer) { + timer_setup(&net->can.stattimer, can_stat_update, + 0); + mod_timer(&net->can.stattimer, + round_jiffies(jiffies + HZ)); + } + net->can.pkg_stats->jiffies_init = jiffies; + can_init_proc(net); + } + + return 0; + + out_free_pkg_stats: + kfree(net->can.pkg_stats); + out_free_rx_alldev_list: + kfree(net->can.rx_alldev_list); + out: + return -ENOMEM; +} + +static void can_pernet_exit(struct net *net) +{ + if (IS_ENABLED(CONFIG_PROC_FS)) { + can_remove_proc(net); + if (stats_timer) + del_timer_sync(&net->can.stattimer); + } + + kfree(net->can.rx_alldev_list); + kfree(net->can.pkg_stats); + kfree(net->can.rcv_lists_stats); +} + +/* af_can module init/exit functions */ + +static struct packet_type can_packet __read_mostly = { + .type = cpu_to_be16(ETH_P_CAN), + .func = can_rcv, +}; + +static struct packet_type canfd_packet __read_mostly = { + .type = cpu_to_be16(ETH_P_CANFD), + .func = canfd_rcv, +}; + +static struct packet_type canxl_packet __read_mostly = { + .type = cpu_to_be16(ETH_P_CANXL), + .func = canxl_rcv, +}; + +static const struct net_proto_family can_family_ops = { + .family = PF_CAN, + .create = can_create, + .owner = THIS_MODULE, +}; + +static struct pernet_operations can_pernet_ops __read_mostly = { + .init = can_pernet_init, + .exit = can_pernet_exit, +}; + +static __init int can_init(void) +{ + int err; + + /* check for correct padding to be able to use the structs similarly */ + BUILD_BUG_ON(offsetof(struct can_frame, len) != + offsetof(struct canfd_frame, len) || + offsetof(struct can_frame, data) != + offsetof(struct canfd_frame, data)); + + pr_info("can: controller area network core\n"); + + rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver), + 0, 0, NULL); + if (!rcv_cache) + return -ENOMEM; + + err = register_pernet_subsys(&can_pernet_ops); + if (err) + goto out_pernet; + + /* protocol register */ + err = sock_register(&can_family_ops); + if (err) + goto out_sock; + + dev_add_pack(&can_packet); + dev_add_pack(&canfd_packet); + dev_add_pack(&canxl_packet); + + return 0; + +out_sock: + unregister_pernet_subsys(&can_pernet_ops); +out_pernet: + kmem_cache_destroy(rcv_cache); + + return err; +} + +static __exit void can_exit(void) +{ + /* protocol unregister */ + dev_remove_pack(&canxl_packet); + dev_remove_pack(&canfd_packet); + dev_remove_pack(&can_packet); + sock_unregister(PF_CAN); + + unregister_pernet_subsys(&can_pernet_ops); + + rcu_barrier(); /* Wait for completion of call_rcu()'s */ + + kmem_cache_destroy(rcv_cache); +} + +module_init(can_init); +module_exit(can_exit); diff --git a/net/can/af_can.h b/net/can/af_can.h new file mode 100644 index 000000000..7c2d9161e --- /dev/null +++ b/net/can/af_can.h @@ -0,0 +1,103 @@ +/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */ +/* Copyright (c) 2002-2007 Volkswagen Group Electronic Research + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Volkswagen nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * Alternatively, provided that this notice is retained in full, this + * software may be distributed under the terms of the GNU General + * Public License ("GPL") version 2, in which case the provisions of the + * GPL apply INSTEAD OF those given above. + * + * The provided data structures and external interfaces from this code + * are not restricted to be used by modules with a GPL compatible license. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + */ + +#ifndef AF_CAN_H +#define AF_CAN_H + +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/list.h> +#include <linux/rcupdate.h> +#include <linux/can.h> + +/* af_can rx dispatcher structures */ + +struct receiver { + struct hlist_node list; + canid_t can_id; + canid_t mask; + unsigned long matches; + void (*func)(struct sk_buff *skb, void *data); + void *data; + char *ident; + struct sock *sk; + struct rcu_head rcu; +}; + +/* statistic structures */ + +/* can be reset e.g. by can_init_stats() */ +struct can_pkg_stats { + unsigned long jiffies_init; + + unsigned long rx_frames; + unsigned long tx_frames; + unsigned long matches; + + unsigned long total_rx_rate; + unsigned long total_tx_rate; + unsigned long total_rx_match_ratio; + + unsigned long current_rx_rate; + unsigned long current_tx_rate; + unsigned long current_rx_match_ratio; + + unsigned long max_rx_rate; + unsigned long max_tx_rate; + unsigned long max_rx_match_ratio; + + unsigned long rx_frames_delta; + unsigned long tx_frames_delta; + unsigned long matches_delta; +}; + +/* persistent statistics */ +struct can_rcv_lists_stats { + unsigned long stats_reset; + unsigned long user_reset; + unsigned long rcv_entries; + unsigned long rcv_entries_max; +}; + +/* function prototypes for the CAN networklayer procfs (proc.c) */ +void can_init_proc(struct net *net); +void can_remove_proc(struct net *net); +void can_stat_update(struct timer_list *t); + +#endif /* AF_CAN_H */ diff --git a/net/can/bcm.c b/net/can/bcm.c new file mode 100644 index 000000000..9168114fc --- /dev/null +++ b/net/can/bcm.c @@ -0,0 +1,1787 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* + * bcm.c - Broadcast Manager to filter/send (cyclic) CAN content + * + * Copyright (c) 2002-2017 Volkswagen Group Electronic Research + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Volkswagen nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * Alternatively, provided that this notice is retained in full, this + * software may be distributed under the terms of the GNU General + * Public License ("GPL") version 2, in which case the provisions of the + * GPL apply INSTEAD OF those given above. + * + * The provided data structures and external interfaces from this code + * are not restricted to be used by modules with a GPL compatible license. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/hrtimer.h> +#include <linux/list.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/uio.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/socket.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/can.h> +#include <linux/can/core.h> +#include <linux/can/skb.h> +#include <linux/can/bcm.h> +#include <linux/slab.h> +#include <net/sock.h> +#include <net/net_namespace.h> + +/* + * To send multiple CAN frame content within TX_SETUP or to filter + * CAN messages with multiplex index within RX_SETUP, the number of + * different filters is limited to 256 due to the one byte index value. + */ +#define MAX_NFRAMES 256 + +/* limit timers to 400 days for sending/timeouts */ +#define BCM_TIMER_SEC_MAX (400 * 24 * 60 * 60) + +/* use of last_frames[index].flags */ +#define RX_RECV 0x40 /* received data for this element */ +#define RX_THR 0x80 /* element not been sent due to throttle feature */ +#define BCM_CAN_FLAGS_MASK 0x3F /* to clean private flags after usage */ + +/* get best masking value for can_rx_register() for a given single can_id */ +#define REGMASK(id) ((id & CAN_EFF_FLAG) ? \ + (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \ + (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG)) + +MODULE_DESCRIPTION("PF_CAN broadcast manager protocol"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); +MODULE_ALIAS("can-proto-2"); + +#define BCM_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_ifindex) + +/* + * easy access to the first 64 bit of can(fd)_frame payload. cp->data is + * 64 bit aligned so the offset has to be multiples of 8 which is ensured + * by the only callers in bcm_rx_cmp_to_index() bcm_rx_handler(). + */ +static inline u64 get_u64(const struct canfd_frame *cp, int offset) +{ + return *(u64 *)(cp->data + offset); +} + +struct bcm_op { + struct list_head list; + struct rcu_head rcu; + int ifindex; + canid_t can_id; + u32 flags; + unsigned long frames_abs, frames_filtered; + struct bcm_timeval ival1, ival2; + struct hrtimer timer, thrtimer; + ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg; + int rx_ifindex; + int cfsiz; + u32 count; + u32 nframes; + u32 currframe; + /* void pointers to arrays of struct can[fd]_frame */ + void *frames; + void *last_frames; + struct canfd_frame sframe; + struct canfd_frame last_sframe; + struct sock *sk; + struct net_device *rx_reg_dev; +}; + +struct bcm_sock { + struct sock sk; + int bound; + int ifindex; + struct list_head notifier; + struct list_head rx_ops; + struct list_head tx_ops; + unsigned long dropped_usr_msgs; + struct proc_dir_entry *bcm_proc_read; + char procname [32]; /* inode number in decimal with \0 */ +}; + +static LIST_HEAD(bcm_notifier_list); +static DEFINE_SPINLOCK(bcm_notifier_lock); +static struct bcm_sock *bcm_busy_notifier; + +static inline struct bcm_sock *bcm_sk(const struct sock *sk) +{ + return (struct bcm_sock *)sk; +} + +static inline ktime_t bcm_timeval_to_ktime(struct bcm_timeval tv) +{ + return ktime_set(tv.tv_sec, tv.tv_usec * NSEC_PER_USEC); +} + +/* check limitations for timeval provided by user */ +static bool bcm_is_invalid_tv(struct bcm_msg_head *msg_head) +{ + if ((msg_head->ival1.tv_sec < 0) || + (msg_head->ival1.tv_sec > BCM_TIMER_SEC_MAX) || + (msg_head->ival1.tv_usec < 0) || + (msg_head->ival1.tv_usec >= USEC_PER_SEC) || + (msg_head->ival2.tv_sec < 0) || + (msg_head->ival2.tv_sec > BCM_TIMER_SEC_MAX) || + (msg_head->ival2.tv_usec < 0) || + (msg_head->ival2.tv_usec >= USEC_PER_SEC)) + return true; + + return false; +} + +#define CFSIZ(flags) ((flags & CAN_FD_FRAME) ? CANFD_MTU : CAN_MTU) +#define OPSIZ sizeof(struct bcm_op) +#define MHSIZ sizeof(struct bcm_msg_head) + +/* + * procfs functions + */ +#if IS_ENABLED(CONFIG_PROC_FS) +static char *bcm_proc_getifname(struct net *net, char *result, int ifindex) +{ + struct net_device *dev; + + if (!ifindex) + return "any"; + + rcu_read_lock(); + dev = dev_get_by_index_rcu(net, ifindex); + if (dev) + strcpy(result, dev->name); + else + strcpy(result, "???"); + rcu_read_unlock(); + + return result; +} + +static int bcm_proc_show(struct seq_file *m, void *v) +{ + char ifname[IFNAMSIZ]; + struct net *net = m->private; + struct sock *sk = (struct sock *)pde_data(m->file->f_inode); + struct bcm_sock *bo = bcm_sk(sk); + struct bcm_op *op; + + seq_printf(m, ">>> socket %pK", sk->sk_socket); + seq_printf(m, " / sk %pK", sk); + seq_printf(m, " / bo %pK", bo); + seq_printf(m, " / dropped %lu", bo->dropped_usr_msgs); + seq_printf(m, " / bound %s", bcm_proc_getifname(net, ifname, bo->ifindex)); + seq_printf(m, " <<<\n"); + + list_for_each_entry(op, &bo->rx_ops, list) { + + unsigned long reduction; + + /* print only active entries & prevent division by zero */ + if (!op->frames_abs) + continue; + + seq_printf(m, "rx_op: %03X %-5s ", op->can_id, + bcm_proc_getifname(net, ifname, op->ifindex)); + + if (op->flags & CAN_FD_FRAME) + seq_printf(m, "(%u)", op->nframes); + else + seq_printf(m, "[%u]", op->nframes); + + seq_printf(m, "%c ", (op->flags & RX_CHECK_DLC) ? 'd' : ' '); + + if (op->kt_ival1) + seq_printf(m, "timeo=%lld ", + (long long)ktime_to_us(op->kt_ival1)); + + if (op->kt_ival2) + seq_printf(m, "thr=%lld ", + (long long)ktime_to_us(op->kt_ival2)); + + seq_printf(m, "# recv %ld (%ld) => reduction: ", + op->frames_filtered, op->frames_abs); + + reduction = 100 - (op->frames_filtered * 100) / op->frames_abs; + + seq_printf(m, "%s%ld%%\n", + (reduction == 100) ? "near " : "", reduction); + } + + list_for_each_entry(op, &bo->tx_ops, list) { + + seq_printf(m, "tx_op: %03X %s ", op->can_id, + bcm_proc_getifname(net, ifname, op->ifindex)); + + if (op->flags & CAN_FD_FRAME) + seq_printf(m, "(%u) ", op->nframes); + else + seq_printf(m, "[%u] ", op->nframes); + + if (op->kt_ival1) + seq_printf(m, "t1=%lld ", + (long long)ktime_to_us(op->kt_ival1)); + + if (op->kt_ival2) + seq_printf(m, "t2=%lld ", + (long long)ktime_to_us(op->kt_ival2)); + + seq_printf(m, "# sent %ld\n", op->frames_abs); + } + seq_putc(m, '\n'); + return 0; +} +#endif /* CONFIG_PROC_FS */ + +/* + * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface + * of the given bcm tx op + */ +static void bcm_can_tx(struct bcm_op *op) +{ + struct sk_buff *skb; + struct net_device *dev; + struct canfd_frame *cf = op->frames + op->cfsiz * op->currframe; + int err; + + /* no target device? => exit */ + if (!op->ifindex) + return; + + dev = dev_get_by_index(sock_net(op->sk), op->ifindex); + if (!dev) { + /* RFC: should this bcm_op remove itself here? */ + return; + } + + skb = alloc_skb(op->cfsiz + sizeof(struct can_skb_priv), gfp_any()); + if (!skb) + goto out; + + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + skb_put_data(skb, cf, op->cfsiz); + + /* send with loopback */ + skb->dev = dev; + can_skb_set_owner(skb, op->sk); + err = can_send(skb, 1); + if (!err) + op->frames_abs++; + + op->currframe++; + + /* reached last frame? */ + if (op->currframe >= op->nframes) + op->currframe = 0; +out: + dev_put(dev); +} + +/* + * bcm_send_to_user - send a BCM message to the userspace + * (consisting of bcm_msg_head + x CAN frames) + */ +static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, + struct canfd_frame *frames, int has_timestamp) +{ + struct sk_buff *skb; + struct canfd_frame *firstframe; + struct sockaddr_can *addr; + struct sock *sk = op->sk; + unsigned int datalen = head->nframes * op->cfsiz; + int err; + + skb = alloc_skb(sizeof(*head) + datalen, gfp_any()); + if (!skb) + return; + + skb_put_data(skb, head, sizeof(*head)); + + if (head->nframes) { + /* CAN frames starting here */ + firstframe = (struct canfd_frame *)skb_tail_pointer(skb); + + skb_put_data(skb, frames, datalen); + + /* + * the BCM uses the flags-element of the canfd_frame + * structure for internal purposes. This is only + * relevant for updates that are generated by the + * BCM, where nframes is 1 + */ + if (head->nframes == 1) + firstframe->flags &= BCM_CAN_FLAGS_MASK; + } + + if (has_timestamp) { + /* restore rx timestamp */ + skb->tstamp = op->rx_stamp; + } + + /* + * Put the datagram to the queue so that bcm_recvmsg() can + * get it from there. We need to pass the interface index to + * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb + * containing the interface index. + */ + + sock_skb_cb_check_size(sizeof(struct sockaddr_can)); + addr = (struct sockaddr_can *)skb->cb; + memset(addr, 0, sizeof(*addr)); + addr->can_family = AF_CAN; + addr->can_ifindex = op->rx_ifindex; + + err = sock_queue_rcv_skb(sk, skb); + if (err < 0) { + struct bcm_sock *bo = bcm_sk(sk); + + kfree_skb(skb); + /* don't care about overflows in this statistic */ + bo->dropped_usr_msgs++; + } +} + +static bool bcm_tx_set_expiry(struct bcm_op *op, struct hrtimer *hrt) +{ + ktime_t ival; + + if (op->kt_ival1 && op->count) + ival = op->kt_ival1; + else if (op->kt_ival2) + ival = op->kt_ival2; + else + return false; + + hrtimer_set_expires(hrt, ktime_add(ktime_get(), ival)); + return true; +} + +static void bcm_tx_start_timer(struct bcm_op *op) +{ + if (bcm_tx_set_expiry(op, &op->timer)) + hrtimer_start_expires(&op->timer, HRTIMER_MODE_ABS_SOFT); +} + +/* bcm_tx_timeout_handler - performs cyclic CAN frame transmissions */ +static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer) +{ + struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); + struct bcm_msg_head msg_head; + + if (op->kt_ival1 && (op->count > 0)) { + op->count--; + if (!op->count && (op->flags & TX_COUNTEVT)) { + + /* create notification to user */ + memset(&msg_head, 0, sizeof(msg_head)); + msg_head.opcode = TX_EXPIRED; + msg_head.flags = op->flags; + msg_head.count = op->count; + msg_head.ival1 = op->ival1; + msg_head.ival2 = op->ival2; + msg_head.can_id = op->can_id; + msg_head.nframes = 0; + + bcm_send_to_user(op, &msg_head, NULL, 0); + } + bcm_can_tx(op); + + } else if (op->kt_ival2) { + bcm_can_tx(op); + } + + return bcm_tx_set_expiry(op, &op->timer) ? + HRTIMER_RESTART : HRTIMER_NORESTART; +} + +/* + * bcm_rx_changed - create a RX_CHANGED notification due to changed content + */ +static void bcm_rx_changed(struct bcm_op *op, struct canfd_frame *data) +{ + struct bcm_msg_head head; + + /* update statistics */ + op->frames_filtered++; + + /* prevent statistics overflow */ + if (op->frames_filtered > ULONG_MAX/100) + op->frames_filtered = op->frames_abs = 0; + + /* this element is not throttled anymore */ + data->flags &= (BCM_CAN_FLAGS_MASK|RX_RECV); + + memset(&head, 0, sizeof(head)); + head.opcode = RX_CHANGED; + head.flags = op->flags; + head.count = op->count; + head.ival1 = op->ival1; + head.ival2 = op->ival2; + head.can_id = op->can_id; + head.nframes = 1; + + bcm_send_to_user(op, &head, data, 1); +} + +/* + * bcm_rx_update_and_send - process a detected relevant receive content change + * 1. update the last received data + * 2. send a notification to the user (if possible) + */ +static void bcm_rx_update_and_send(struct bcm_op *op, + struct canfd_frame *lastdata, + const struct canfd_frame *rxdata) +{ + memcpy(lastdata, rxdata, op->cfsiz); + + /* mark as used and throttled by default */ + lastdata->flags |= (RX_RECV|RX_THR); + + /* throttling mode inactive ? */ + if (!op->kt_ival2) { + /* send RX_CHANGED to the user immediately */ + bcm_rx_changed(op, lastdata); + return; + } + + /* with active throttling timer we are just done here */ + if (hrtimer_active(&op->thrtimer)) + return; + + /* first reception with enabled throttling mode */ + if (!op->kt_lastmsg) + goto rx_changed_settime; + + /* got a second frame inside a potential throttle period? */ + if (ktime_us_delta(ktime_get(), op->kt_lastmsg) < + ktime_to_us(op->kt_ival2)) { + /* do not send the saved data - only start throttle timer */ + hrtimer_start(&op->thrtimer, + ktime_add(op->kt_lastmsg, op->kt_ival2), + HRTIMER_MODE_ABS_SOFT); + return; + } + + /* the gap was that big, that throttling was not needed here */ +rx_changed_settime: + bcm_rx_changed(op, lastdata); + op->kt_lastmsg = ktime_get(); +} + +/* + * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly + * received data stored in op->last_frames[] + */ +static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index, + const struct canfd_frame *rxdata) +{ + struct canfd_frame *cf = op->frames + op->cfsiz * index; + struct canfd_frame *lcf = op->last_frames + op->cfsiz * index; + int i; + + /* + * no one uses the MSBs of flags for comparison, + * so we use it here to detect the first time of reception + */ + + if (!(lcf->flags & RX_RECV)) { + /* received data for the first time => send update to user */ + bcm_rx_update_and_send(op, lcf, rxdata); + return; + } + + /* do a real check in CAN frame data section */ + for (i = 0; i < rxdata->len; i += 8) { + if ((get_u64(cf, i) & get_u64(rxdata, i)) != + (get_u64(cf, i) & get_u64(lcf, i))) { + bcm_rx_update_and_send(op, lcf, rxdata); + return; + } + } + + if (op->flags & RX_CHECK_DLC) { + /* do a real check in CAN frame length */ + if (rxdata->len != lcf->len) { + bcm_rx_update_and_send(op, lcf, rxdata); + return; + } + } +} + +/* + * bcm_rx_starttimer - enable timeout monitoring for CAN frame reception + */ +static void bcm_rx_starttimer(struct bcm_op *op) +{ + if (op->flags & RX_NO_AUTOTIMER) + return; + + if (op->kt_ival1) + hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL_SOFT); +} + +/* bcm_rx_timeout_handler - when the (cyclic) CAN frame reception timed out */ +static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer) +{ + struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); + struct bcm_msg_head msg_head; + + /* if user wants to be informed, when cyclic CAN-Messages come back */ + if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) { + /* clear received CAN frames to indicate 'nothing received' */ + memset(op->last_frames, 0, op->nframes * op->cfsiz); + } + + /* create notification to user */ + memset(&msg_head, 0, sizeof(msg_head)); + msg_head.opcode = RX_TIMEOUT; + msg_head.flags = op->flags; + msg_head.count = op->count; + msg_head.ival1 = op->ival1; + msg_head.ival2 = op->ival2; + msg_head.can_id = op->can_id; + msg_head.nframes = 0; + + bcm_send_to_user(op, &msg_head, NULL, 0); + + return HRTIMER_NORESTART; +} + +/* + * bcm_rx_do_flush - helper for bcm_rx_thr_flush + */ +static inline int bcm_rx_do_flush(struct bcm_op *op, unsigned int index) +{ + struct canfd_frame *lcf = op->last_frames + op->cfsiz * index; + + if ((op->last_frames) && (lcf->flags & RX_THR)) { + bcm_rx_changed(op, lcf); + return 1; + } + return 0; +} + +/* + * bcm_rx_thr_flush - Check for throttled data and send it to the userspace + */ +static int bcm_rx_thr_flush(struct bcm_op *op) +{ + int updated = 0; + + if (op->nframes > 1) { + unsigned int i; + + /* for MUX filter we start at index 1 */ + for (i = 1; i < op->nframes; i++) + updated += bcm_rx_do_flush(op, i); + + } else { + /* for RX_FILTER_ID and simple filter */ + updated += bcm_rx_do_flush(op, 0); + } + + return updated; +} + +/* + * bcm_rx_thr_handler - the time for blocked content updates is over now: + * Check for throttled data and send it to the userspace + */ +static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer) +{ + struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer); + + if (bcm_rx_thr_flush(op)) { + hrtimer_forward_now(hrtimer, op->kt_ival2); + return HRTIMER_RESTART; + } else { + /* rearm throttle handling */ + op->kt_lastmsg = 0; + return HRTIMER_NORESTART; + } +} + +/* + * bcm_rx_handler - handle a CAN frame reception + */ +static void bcm_rx_handler(struct sk_buff *skb, void *data) +{ + struct bcm_op *op = (struct bcm_op *)data; + const struct canfd_frame *rxframe = (struct canfd_frame *)skb->data; + unsigned int i; + + if (op->can_id != rxframe->can_id) + return; + + /* make sure to handle the correct frame type (CAN / CAN FD) */ + if (op->flags & CAN_FD_FRAME) { + if (!can_is_canfd_skb(skb)) + return; + } else { + if (!can_is_can_skb(skb)) + return; + } + + /* disable timeout */ + hrtimer_cancel(&op->timer); + + /* save rx timestamp */ + op->rx_stamp = skb->tstamp; + /* save originator for recvfrom() */ + op->rx_ifindex = skb->dev->ifindex; + /* update statistics */ + op->frames_abs++; + + if (op->flags & RX_RTR_FRAME) { + /* send reply for RTR-request (placed in op->frames[0]) */ + bcm_can_tx(op); + return; + } + + if (op->flags & RX_FILTER_ID) { + /* the easiest case */ + bcm_rx_update_and_send(op, op->last_frames, rxframe); + goto rx_starttimer; + } + + if (op->nframes == 1) { + /* simple compare with index 0 */ + bcm_rx_cmp_to_index(op, 0, rxframe); + goto rx_starttimer; + } + + if (op->nframes > 1) { + /* + * multiplex compare + * + * find the first multiplex mask that fits. + * Remark: The MUX-mask is stored in index 0 - but only the + * first 64 bits of the frame data[] are relevant (CAN FD) + */ + + for (i = 1; i < op->nframes; i++) { + if ((get_u64(op->frames, 0) & get_u64(rxframe, 0)) == + (get_u64(op->frames, 0) & + get_u64(op->frames + op->cfsiz * i, 0))) { + bcm_rx_cmp_to_index(op, i, rxframe); + break; + } + } + } + +rx_starttimer: + bcm_rx_starttimer(op); +} + +/* + * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements + */ +static struct bcm_op *bcm_find_op(struct list_head *ops, + struct bcm_msg_head *mh, int ifindex) +{ + struct bcm_op *op; + + list_for_each_entry(op, ops, list) { + if ((op->can_id == mh->can_id) && (op->ifindex == ifindex) && + (op->flags & CAN_FD_FRAME) == (mh->flags & CAN_FD_FRAME)) + return op; + } + + return NULL; +} + +static void bcm_free_op_rcu(struct rcu_head *rcu_head) +{ + struct bcm_op *op = container_of(rcu_head, struct bcm_op, rcu); + + if ((op->frames) && (op->frames != &op->sframe)) + kfree(op->frames); + + if ((op->last_frames) && (op->last_frames != &op->last_sframe)) + kfree(op->last_frames); + + kfree(op); +} + +static void bcm_remove_op(struct bcm_op *op) +{ + hrtimer_cancel(&op->timer); + hrtimer_cancel(&op->thrtimer); + + call_rcu(&op->rcu, bcm_free_op_rcu); +} + +static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op) +{ + if (op->rx_reg_dev == dev) { + can_rx_unregister(dev_net(dev), dev, op->can_id, + REGMASK(op->can_id), bcm_rx_handler, op); + + /* mark as removed subscription */ + op->rx_reg_dev = NULL; + } else + printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device " + "mismatch %p %p\n", op->rx_reg_dev, dev); +} + +/* + * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops) + */ +static int bcm_delete_rx_op(struct list_head *ops, struct bcm_msg_head *mh, + int ifindex) +{ + struct bcm_op *op, *n; + + list_for_each_entry_safe(op, n, ops, list) { + if ((op->can_id == mh->can_id) && (op->ifindex == ifindex) && + (op->flags & CAN_FD_FRAME) == (mh->flags & CAN_FD_FRAME)) { + + /* disable automatic timer on frame reception */ + op->flags |= RX_NO_AUTOTIMER; + + /* + * Don't care if we're bound or not (due to netdev + * problems) can_rx_unregister() is always a save + * thing to do here. + */ + if (op->ifindex) { + /* + * Only remove subscriptions that had not + * been removed due to NETDEV_UNREGISTER + * in bcm_notifier() + */ + if (op->rx_reg_dev) { + struct net_device *dev; + + dev = dev_get_by_index(sock_net(op->sk), + op->ifindex); + if (dev) { + bcm_rx_unreg(dev, op); + dev_put(dev); + } + } + } else + can_rx_unregister(sock_net(op->sk), NULL, + op->can_id, + REGMASK(op->can_id), + bcm_rx_handler, op); + + list_del(&op->list); + bcm_remove_op(op); + return 1; /* done */ + } + } + + return 0; /* not found */ +} + +/* + * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops) + */ +static int bcm_delete_tx_op(struct list_head *ops, struct bcm_msg_head *mh, + int ifindex) +{ + struct bcm_op *op, *n; + + list_for_each_entry_safe(op, n, ops, list) { + if ((op->can_id == mh->can_id) && (op->ifindex == ifindex) && + (op->flags & CAN_FD_FRAME) == (mh->flags & CAN_FD_FRAME)) { + list_del(&op->list); + bcm_remove_op(op); + return 1; /* done */ + } + } + + return 0; /* not found */ +} + +/* + * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg) + */ +static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head, + int ifindex) +{ + struct bcm_op *op = bcm_find_op(ops, msg_head, ifindex); + + if (!op) + return -EINVAL; + + /* put current values into msg_head */ + msg_head->flags = op->flags; + msg_head->count = op->count; + msg_head->ival1 = op->ival1; + msg_head->ival2 = op->ival2; + msg_head->nframes = op->nframes; + + bcm_send_to_user(op, msg_head, op->frames, 0); + + return MHSIZ; +} + +/* + * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg) + */ +static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, + int ifindex, struct sock *sk) +{ + struct bcm_sock *bo = bcm_sk(sk); + struct bcm_op *op; + struct canfd_frame *cf; + unsigned int i; + int err; + + /* we need a real device to send frames */ + if (!ifindex) + return -ENODEV; + + /* check nframes boundaries - we need at least one CAN frame */ + if (msg_head->nframes < 1 || msg_head->nframes > MAX_NFRAMES) + return -EINVAL; + + /* check timeval limitations */ + if ((msg_head->flags & SETTIMER) && bcm_is_invalid_tv(msg_head)) + return -EINVAL; + + /* check the given can_id */ + op = bcm_find_op(&bo->tx_ops, msg_head, ifindex); + if (op) { + /* update existing BCM operation */ + + /* + * Do we need more space for the CAN frames than currently + * allocated? -> This is a _really_ unusual use-case and + * therefore (complexity / locking) it is not supported. + */ + if (msg_head->nframes > op->nframes) + return -E2BIG; + + /* update CAN frames content */ + for (i = 0; i < msg_head->nframes; i++) { + + cf = op->frames + op->cfsiz * i; + err = memcpy_from_msg((u8 *)cf, msg, op->cfsiz); + + if (op->flags & CAN_FD_FRAME) { + if (cf->len > 64) + err = -EINVAL; + } else { + if (cf->len > 8) + err = -EINVAL; + } + + if (err < 0) + return err; + + if (msg_head->flags & TX_CP_CAN_ID) { + /* copy can_id into frame */ + cf->can_id = msg_head->can_id; + } + } + op->flags = msg_head->flags; + + } else { + /* insert new BCM operation for the given can_id */ + + op = kzalloc(OPSIZ, GFP_KERNEL); + if (!op) + return -ENOMEM; + + op->can_id = msg_head->can_id; + op->cfsiz = CFSIZ(msg_head->flags); + op->flags = msg_head->flags; + + /* create array for CAN frames and copy the data */ + if (msg_head->nframes > 1) { + op->frames = kmalloc_array(msg_head->nframes, + op->cfsiz, + GFP_KERNEL); + if (!op->frames) { + kfree(op); + return -ENOMEM; + } + } else + op->frames = &op->sframe; + + for (i = 0; i < msg_head->nframes; i++) { + + cf = op->frames + op->cfsiz * i; + err = memcpy_from_msg((u8 *)cf, msg, op->cfsiz); + if (err < 0) + goto free_op; + + if (op->flags & CAN_FD_FRAME) { + if (cf->len > 64) + err = -EINVAL; + } else { + if (cf->len > 8) + err = -EINVAL; + } + + if (err < 0) + goto free_op; + + if (msg_head->flags & TX_CP_CAN_ID) { + /* copy can_id into frame */ + cf->can_id = msg_head->can_id; + } + } + + /* tx_ops never compare with previous received messages */ + op->last_frames = NULL; + + /* bcm_can_tx / bcm_tx_timeout_handler needs this */ + op->sk = sk; + op->ifindex = ifindex; + + /* initialize uninitialized (kzalloc) structure */ + hrtimer_init(&op->timer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + op->timer.function = bcm_tx_timeout_handler; + + /* currently unused in tx_ops */ + hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + + /* add this bcm_op to the list of the tx_ops */ + list_add(&op->list, &bo->tx_ops); + + } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */ + + if (op->nframes != msg_head->nframes) { + op->nframes = msg_head->nframes; + /* start multiple frame transmission with index 0 */ + op->currframe = 0; + } + + /* check flags */ + + if (op->flags & TX_RESET_MULTI_IDX) { + /* start multiple frame transmission with index 0 */ + op->currframe = 0; + } + + if (op->flags & SETTIMER) { + /* set timer values */ + op->count = msg_head->count; + op->ival1 = msg_head->ival1; + op->ival2 = msg_head->ival2; + op->kt_ival1 = bcm_timeval_to_ktime(msg_head->ival1); + op->kt_ival2 = bcm_timeval_to_ktime(msg_head->ival2); + + /* disable an active timer due to zero values? */ + if (!op->kt_ival1 && !op->kt_ival2) + hrtimer_cancel(&op->timer); + } + + if (op->flags & STARTTIMER) { + hrtimer_cancel(&op->timer); + /* spec: send CAN frame when starting timer */ + op->flags |= TX_ANNOUNCE; + } + + if (op->flags & TX_ANNOUNCE) { + bcm_can_tx(op); + if (op->count) + op->count--; + } + + if (op->flags & STARTTIMER) + bcm_tx_start_timer(op); + + return msg_head->nframes * op->cfsiz + MHSIZ; + +free_op: + if (op->frames != &op->sframe) + kfree(op->frames); + kfree(op); + return err; +} + +/* + * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg) + */ +static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, + int ifindex, struct sock *sk) +{ + struct bcm_sock *bo = bcm_sk(sk); + struct bcm_op *op; + int do_rx_register; + int err = 0; + + if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) { + /* be robust against wrong usage ... */ + msg_head->flags |= RX_FILTER_ID; + /* ignore trailing garbage */ + msg_head->nframes = 0; + } + + /* the first element contains the mux-mask => MAX_NFRAMES + 1 */ + if (msg_head->nframes > MAX_NFRAMES + 1) + return -EINVAL; + + if ((msg_head->flags & RX_RTR_FRAME) && + ((msg_head->nframes != 1) || + (!(msg_head->can_id & CAN_RTR_FLAG)))) + return -EINVAL; + + /* check timeval limitations */ + if ((msg_head->flags & SETTIMER) && bcm_is_invalid_tv(msg_head)) + return -EINVAL; + + /* check the given can_id */ + op = bcm_find_op(&bo->rx_ops, msg_head, ifindex); + if (op) { + /* update existing BCM operation */ + + /* + * Do we need more space for the CAN frames than currently + * allocated? -> This is a _really_ unusual use-case and + * therefore (complexity / locking) it is not supported. + */ + if (msg_head->nframes > op->nframes) + return -E2BIG; + + if (msg_head->nframes) { + /* update CAN frames content */ + err = memcpy_from_msg(op->frames, msg, + msg_head->nframes * op->cfsiz); + if (err < 0) + return err; + + /* clear last_frames to indicate 'nothing received' */ + memset(op->last_frames, 0, msg_head->nframes * op->cfsiz); + } + + op->nframes = msg_head->nframes; + op->flags = msg_head->flags; + + /* Only an update -> do not call can_rx_register() */ + do_rx_register = 0; + + } else { + /* insert new BCM operation for the given can_id */ + op = kzalloc(OPSIZ, GFP_KERNEL); + if (!op) + return -ENOMEM; + + op->can_id = msg_head->can_id; + op->nframes = msg_head->nframes; + op->cfsiz = CFSIZ(msg_head->flags); + op->flags = msg_head->flags; + + if (msg_head->nframes > 1) { + /* create array for CAN frames and copy the data */ + op->frames = kmalloc_array(msg_head->nframes, + op->cfsiz, + GFP_KERNEL); + if (!op->frames) { + kfree(op); + return -ENOMEM; + } + + /* create and init array for received CAN frames */ + op->last_frames = kcalloc(msg_head->nframes, + op->cfsiz, + GFP_KERNEL); + if (!op->last_frames) { + kfree(op->frames); + kfree(op); + return -ENOMEM; + } + + } else { + op->frames = &op->sframe; + op->last_frames = &op->last_sframe; + } + + if (msg_head->nframes) { + err = memcpy_from_msg(op->frames, msg, + msg_head->nframes * op->cfsiz); + if (err < 0) { + if (op->frames != &op->sframe) + kfree(op->frames); + if (op->last_frames != &op->last_sframe) + kfree(op->last_frames); + kfree(op); + return err; + } + } + + /* bcm_can_tx / bcm_tx_timeout_handler needs this */ + op->sk = sk; + op->ifindex = ifindex; + + /* ifindex for timeout events w/o previous frame reception */ + op->rx_ifindex = ifindex; + + /* initialize uninitialized (kzalloc) structure */ + hrtimer_init(&op->timer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + op->timer.function = bcm_rx_timeout_handler; + + hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + op->thrtimer.function = bcm_rx_thr_handler; + + /* add this bcm_op to the list of the rx_ops */ + list_add(&op->list, &bo->rx_ops); + + /* call can_rx_register() */ + do_rx_register = 1; + + } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */ + + /* check flags */ + + if (op->flags & RX_RTR_FRAME) { + struct canfd_frame *frame0 = op->frames; + + /* no timers in RTR-mode */ + hrtimer_cancel(&op->thrtimer); + hrtimer_cancel(&op->timer); + + /* + * funny feature in RX(!)_SETUP only for RTR-mode: + * copy can_id into frame BUT without RTR-flag to + * prevent a full-load-loopback-test ... ;-] + */ + if ((op->flags & TX_CP_CAN_ID) || + (frame0->can_id == op->can_id)) + frame0->can_id = op->can_id & ~CAN_RTR_FLAG; + + } else { + if (op->flags & SETTIMER) { + + /* set timer value */ + op->ival1 = msg_head->ival1; + op->ival2 = msg_head->ival2; + op->kt_ival1 = bcm_timeval_to_ktime(msg_head->ival1); + op->kt_ival2 = bcm_timeval_to_ktime(msg_head->ival2); + + /* disable an active timer due to zero value? */ + if (!op->kt_ival1) + hrtimer_cancel(&op->timer); + + /* + * In any case cancel the throttle timer, flush + * potentially blocked msgs and reset throttle handling + */ + op->kt_lastmsg = 0; + hrtimer_cancel(&op->thrtimer); + bcm_rx_thr_flush(op); + } + + if ((op->flags & STARTTIMER) && op->kt_ival1) + hrtimer_start(&op->timer, op->kt_ival1, + HRTIMER_MODE_REL_SOFT); + } + + /* now we can register for can_ids, if we added a new bcm_op */ + if (do_rx_register) { + if (ifindex) { + struct net_device *dev; + + dev = dev_get_by_index(sock_net(sk), ifindex); + if (dev) { + err = can_rx_register(sock_net(sk), dev, + op->can_id, + REGMASK(op->can_id), + bcm_rx_handler, op, + "bcm", sk); + + op->rx_reg_dev = dev; + dev_put(dev); + } + + } else + err = can_rx_register(sock_net(sk), NULL, op->can_id, + REGMASK(op->can_id), + bcm_rx_handler, op, "bcm", sk); + if (err) { + /* this bcm rx op is broken -> remove it */ + list_del(&op->list); + bcm_remove_op(op); + return err; + } + } + + return msg_head->nframes * op->cfsiz + MHSIZ; +} + +/* + * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg) + */ +static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk, + int cfsiz) +{ + struct sk_buff *skb; + struct net_device *dev; + int err; + + /* we need a real device to send frames */ + if (!ifindex) + return -ENODEV; + + skb = alloc_skb(cfsiz + sizeof(struct can_skb_priv), GFP_KERNEL); + if (!skb) + return -ENOMEM; + + can_skb_reserve(skb); + + err = memcpy_from_msg(skb_put(skb, cfsiz), msg, cfsiz); + if (err < 0) { + kfree_skb(skb); + return err; + } + + dev = dev_get_by_index(sock_net(sk), ifindex); + if (!dev) { + kfree_skb(skb); + return -ENODEV; + } + + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + skb->dev = dev; + can_skb_set_owner(skb, sk); + err = can_send(skb, 1); /* send with loopback */ + dev_put(dev); + + if (err) + return err; + + return cfsiz + MHSIZ; +} + +/* + * bcm_sendmsg - process BCM commands (opcodes) from the userspace + */ +static int bcm_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) +{ + struct sock *sk = sock->sk; + struct bcm_sock *bo = bcm_sk(sk); + int ifindex = bo->ifindex; /* default ifindex for this bcm_op */ + struct bcm_msg_head msg_head; + int cfsiz; + int ret; /* read bytes or error codes as return value */ + + if (!bo->bound) + return -ENOTCONN; + + /* check for valid message length from userspace */ + if (size < MHSIZ) + return -EINVAL; + + /* read message head information */ + ret = memcpy_from_msg((u8 *)&msg_head, msg, MHSIZ); + if (ret < 0) + return ret; + + cfsiz = CFSIZ(msg_head.flags); + if ((size - MHSIZ) % cfsiz) + return -EINVAL; + + /* check for alternative ifindex for this bcm_op */ + + if (!ifindex && msg->msg_name) { + /* no bound device as default => check msg_name */ + DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); + + if (msg->msg_namelen < BCM_MIN_NAMELEN) + return -EINVAL; + + if (addr->can_family != AF_CAN) + return -EINVAL; + + /* ifindex from sendto() */ + ifindex = addr->can_ifindex; + + if (ifindex) { + struct net_device *dev; + + dev = dev_get_by_index(sock_net(sk), ifindex); + if (!dev) + return -ENODEV; + + if (dev->type != ARPHRD_CAN) { + dev_put(dev); + return -ENODEV; + } + + dev_put(dev); + } + } + + lock_sock(sk); + + switch (msg_head.opcode) { + + case TX_SETUP: + ret = bcm_tx_setup(&msg_head, msg, ifindex, sk); + break; + + case RX_SETUP: + ret = bcm_rx_setup(&msg_head, msg, ifindex, sk); + break; + + case TX_DELETE: + if (bcm_delete_tx_op(&bo->tx_ops, &msg_head, ifindex)) + ret = MHSIZ; + else + ret = -EINVAL; + break; + + case RX_DELETE: + if (bcm_delete_rx_op(&bo->rx_ops, &msg_head, ifindex)) + ret = MHSIZ; + else + ret = -EINVAL; + break; + + case TX_READ: + /* reuse msg_head for the reply to TX_READ */ + msg_head.opcode = TX_STATUS; + ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex); + break; + + case RX_READ: + /* reuse msg_head for the reply to RX_READ */ + msg_head.opcode = RX_STATUS; + ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex); + break; + + case TX_SEND: + /* we need exactly one CAN frame behind the msg head */ + if ((msg_head.nframes != 1) || (size != cfsiz + MHSIZ)) + ret = -EINVAL; + else + ret = bcm_tx_send(msg, ifindex, sk, cfsiz); + break; + + default: + ret = -EINVAL; + break; + } + + release_sock(sk); + + return ret; +} + +/* + * notification handler for netdevice status changes + */ +static void bcm_notify(struct bcm_sock *bo, unsigned long msg, + struct net_device *dev) +{ + struct sock *sk = &bo->sk; + struct bcm_op *op; + int notify_enodev = 0; + + if (!net_eq(dev_net(dev), sock_net(sk))) + return; + + switch (msg) { + + case NETDEV_UNREGISTER: + lock_sock(sk); + + /* remove device specific receive entries */ + list_for_each_entry(op, &bo->rx_ops, list) + if (op->rx_reg_dev == dev) + bcm_rx_unreg(dev, op); + + /* remove device reference, if this is our bound device */ + if (bo->bound && bo->ifindex == dev->ifindex) { + bo->bound = 0; + bo->ifindex = 0; + notify_enodev = 1; + } + + release_sock(sk); + + if (notify_enodev) { + sk->sk_err = ENODEV; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + } + break; + + case NETDEV_DOWN: + if (bo->bound && bo->ifindex == dev->ifindex) { + sk->sk_err = ENETDOWN; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + } + } +} + +static int bcm_notifier(struct notifier_block *nb, unsigned long msg, + void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + + if (dev->type != ARPHRD_CAN) + return NOTIFY_DONE; + if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN) + return NOTIFY_DONE; + if (unlikely(bcm_busy_notifier)) /* Check for reentrant bug. */ + return NOTIFY_DONE; + + spin_lock(&bcm_notifier_lock); + list_for_each_entry(bcm_busy_notifier, &bcm_notifier_list, notifier) { + spin_unlock(&bcm_notifier_lock); + bcm_notify(bcm_busy_notifier, msg, dev); + spin_lock(&bcm_notifier_lock); + } + bcm_busy_notifier = NULL; + spin_unlock(&bcm_notifier_lock); + return NOTIFY_DONE; +} + +/* + * initial settings for all BCM sockets to be set at socket creation time + */ +static int bcm_init(struct sock *sk) +{ + struct bcm_sock *bo = bcm_sk(sk); + + bo->bound = 0; + bo->ifindex = 0; + bo->dropped_usr_msgs = 0; + bo->bcm_proc_read = NULL; + + INIT_LIST_HEAD(&bo->tx_ops); + INIT_LIST_HEAD(&bo->rx_ops); + + /* set notifier */ + spin_lock(&bcm_notifier_lock); + list_add_tail(&bo->notifier, &bcm_notifier_list); + spin_unlock(&bcm_notifier_lock); + + return 0; +} + +/* + * standard socket functions + */ +static int bcm_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct net *net; + struct bcm_sock *bo; + struct bcm_op *op, *next; + + if (!sk) + return 0; + + net = sock_net(sk); + bo = bcm_sk(sk); + + /* remove bcm_ops, timer, rx_unregister(), etc. */ + + spin_lock(&bcm_notifier_lock); + while (bcm_busy_notifier == bo) { + spin_unlock(&bcm_notifier_lock); + schedule_timeout_uninterruptible(1); + spin_lock(&bcm_notifier_lock); + } + list_del(&bo->notifier); + spin_unlock(&bcm_notifier_lock); + + lock_sock(sk); + +#if IS_ENABLED(CONFIG_PROC_FS) + /* remove procfs entry */ + if (net->can.bcmproc_dir && bo->bcm_proc_read) + remove_proc_entry(bo->procname, net->can.bcmproc_dir); +#endif /* CONFIG_PROC_FS */ + + list_for_each_entry_safe(op, next, &bo->tx_ops, list) + bcm_remove_op(op); + + list_for_each_entry_safe(op, next, &bo->rx_ops, list) { + /* + * Don't care if we're bound or not (due to netdev problems) + * can_rx_unregister() is always a save thing to do here. + */ + if (op->ifindex) { + /* + * Only remove subscriptions that had not + * been removed due to NETDEV_UNREGISTER + * in bcm_notifier() + */ + if (op->rx_reg_dev) { + struct net_device *dev; + + dev = dev_get_by_index(net, op->ifindex); + if (dev) { + bcm_rx_unreg(dev, op); + dev_put(dev); + } + } + } else + can_rx_unregister(net, NULL, op->can_id, + REGMASK(op->can_id), + bcm_rx_handler, op); + + } + + synchronize_rcu(); + + list_for_each_entry_safe(op, next, &bo->rx_ops, list) + bcm_remove_op(op); + + /* remove device reference */ + if (bo->bound) { + bo->bound = 0; + bo->ifindex = 0; + } + + sock_orphan(sk); + sock->sk = NULL; + + release_sock(sk); + sock_put(sk); + + return 0; +} + +static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len, + int flags) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct sock *sk = sock->sk; + struct bcm_sock *bo = bcm_sk(sk); + struct net *net = sock_net(sk); + int ret = 0; + + if (len < BCM_MIN_NAMELEN) + return -EINVAL; + + lock_sock(sk); + + if (bo->bound) { + ret = -EISCONN; + goto fail; + } + + /* bind a device to this socket */ + if (addr->can_ifindex) { + struct net_device *dev; + + dev = dev_get_by_index(net, addr->can_ifindex); + if (!dev) { + ret = -ENODEV; + goto fail; + } + if (dev->type != ARPHRD_CAN) { + dev_put(dev); + ret = -ENODEV; + goto fail; + } + + bo->ifindex = dev->ifindex; + dev_put(dev); + + } else { + /* no interface reference for ifindex = 0 ('any' CAN device) */ + bo->ifindex = 0; + } + +#if IS_ENABLED(CONFIG_PROC_FS) + if (net->can.bcmproc_dir) { + /* unique socket address as filename */ + sprintf(bo->procname, "%lu", sock_i_ino(sk)); + bo->bcm_proc_read = proc_create_net_single(bo->procname, 0644, + net->can.bcmproc_dir, + bcm_proc_show, sk); + if (!bo->bcm_proc_read) { + ret = -ENOMEM; + goto fail; + } + } +#endif /* CONFIG_PROC_FS */ + + bo->bound = 1; + +fail: + release_sock(sk); + + return ret; +} + +static int bcm_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags) +{ + struct sock *sk = sock->sk; + struct sk_buff *skb; + int error = 0; + int err; + + skb = skb_recv_datagram(sk, flags, &error); + if (!skb) + return error; + + if (skb->len < size) + size = skb->len; + + err = memcpy_to_msg(msg, skb->data, size); + if (err < 0) { + skb_free_datagram(sk, skb); + return err; + } + + sock_recv_cmsgs(msg, sk, skb); + + if (msg->msg_name) { + __sockaddr_check_size(BCM_MIN_NAMELEN); + msg->msg_namelen = BCM_MIN_NAMELEN; + memcpy(msg->msg_name, skb->cb, msg->msg_namelen); + } + + skb_free_datagram(sk, skb); + + return size; +} + +static int bcm_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + /* no ioctls for socket layer -> hand it down to NIC layer */ + return -ENOIOCTLCMD; +} + +static const struct proto_ops bcm_ops = { + .family = PF_CAN, + .release = bcm_release, + .bind = sock_no_bind, + .connect = bcm_connect, + .socketpair = sock_no_socketpair, + .accept = sock_no_accept, + .getname = sock_no_getname, + .poll = datagram_poll, + .ioctl = bcm_sock_no_ioctlcmd, + .gettstamp = sock_gettstamp, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .sendmsg = bcm_sendmsg, + .recvmsg = bcm_recvmsg, + .mmap = sock_no_mmap, +}; + +static struct proto bcm_proto __read_mostly = { + .name = "CAN_BCM", + .owner = THIS_MODULE, + .obj_size = sizeof(struct bcm_sock), + .init = bcm_init, +}; + +static const struct can_proto bcm_can_proto = { + .type = SOCK_DGRAM, + .protocol = CAN_BCM, + .ops = &bcm_ops, + .prot = &bcm_proto, +}; + +static int canbcm_pernet_init(struct net *net) +{ +#if IS_ENABLED(CONFIG_PROC_FS) + /* create /proc/net/can-bcm directory */ + net->can.bcmproc_dir = proc_net_mkdir(net, "can-bcm", net->proc_net); +#endif /* CONFIG_PROC_FS */ + + return 0; +} + +static void canbcm_pernet_exit(struct net *net) +{ +#if IS_ENABLED(CONFIG_PROC_FS) + /* remove /proc/net/can-bcm directory */ + if (net->can.bcmproc_dir) + remove_proc_entry("can-bcm", net->proc_net); +#endif /* CONFIG_PROC_FS */ +} + +static struct pernet_operations canbcm_pernet_ops __read_mostly = { + .init = canbcm_pernet_init, + .exit = canbcm_pernet_exit, +}; + +static struct notifier_block canbcm_notifier = { + .notifier_call = bcm_notifier +}; + +static int __init bcm_module_init(void) +{ + int err; + + pr_info("can: broadcast manager protocol\n"); + + err = register_pernet_subsys(&canbcm_pernet_ops); + if (err) + return err; + + err = register_netdevice_notifier(&canbcm_notifier); + if (err) + goto register_notifier_failed; + + err = can_proto_register(&bcm_can_proto); + if (err < 0) { + printk(KERN_ERR "can: registration of bcm protocol failed\n"); + goto register_proto_failed; + } + + return 0; + +register_proto_failed: + unregister_netdevice_notifier(&canbcm_notifier); +register_notifier_failed: + unregister_pernet_subsys(&canbcm_pernet_ops); + return err; +} + +static void __exit bcm_module_exit(void) +{ + can_proto_unregister(&bcm_can_proto); + unregister_netdevice_notifier(&canbcm_notifier); + unregister_pernet_subsys(&canbcm_pernet_ops); +} + +module_init(bcm_module_init); +module_exit(bcm_module_exit); diff --git a/net/can/gw.c b/net/can/gw.c new file mode 100644 index 000000000..375288269 --- /dev/null +++ b/net/can/gw.c @@ -0,0 +1,1336 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* gw.c - CAN frame Gateway/Router/Bridge with netlink interface + * + * Copyright (c) 2019 Volkswagen Group Electronic Research + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Volkswagen nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * Alternatively, provided that this notice is retained in full, this + * software may be distributed under the terms of the GNU General + * Public License ("GPL") version 2, in which case the provisions of the + * GPL apply INSTEAD OF those given above. + * + * The provided data structures and external interfaces from this code + * are not restricted to be used by modules with a GPL compatible license. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/spinlock.h> +#include <linux/rcupdate.h> +#include <linux/rculist.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/can.h> +#include <linux/can/core.h> +#include <linux/can/skb.h> +#include <linux/can/gw.h> +#include <net/rtnetlink.h> +#include <net/net_namespace.h> +#include <net/sock.h> + +#define CAN_GW_NAME "can-gw" + +MODULE_DESCRIPTION("PF_CAN netlink gateway"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); +MODULE_ALIAS(CAN_GW_NAME); + +#define CGW_MIN_HOPS 1 +#define CGW_MAX_HOPS 6 +#define CGW_DEFAULT_HOPS 1 + +static unsigned int max_hops __read_mostly = CGW_DEFAULT_HOPS; +module_param(max_hops, uint, 0444); +MODULE_PARM_DESC(max_hops, + "maximum " CAN_GW_NAME " routing hops for CAN frames " + "(valid values: " __stringify(CGW_MIN_HOPS) "-" + __stringify(CGW_MAX_HOPS) " hops, " + "default: " __stringify(CGW_DEFAULT_HOPS) ")"); + +static struct notifier_block notifier; +static struct kmem_cache *cgw_cache __read_mostly; + +/* structure that contains the (on-the-fly) CAN frame modifications */ +struct cf_mod { + struct { + struct canfd_frame and; + struct canfd_frame or; + struct canfd_frame xor; + struct canfd_frame set; + } modframe; + struct { + u8 and; + u8 or; + u8 xor; + u8 set; + } modtype; + void (*modfunc[MAX_MODFUNCTIONS])(struct canfd_frame *cf, + struct cf_mod *mod); + + /* CAN frame checksum calculation after CAN frame modifications */ + struct { + struct cgw_csum_xor xor; + struct cgw_csum_crc8 crc8; + } csum; + struct { + void (*xor)(struct canfd_frame *cf, + struct cgw_csum_xor *xor); + void (*crc8)(struct canfd_frame *cf, + struct cgw_csum_crc8 *crc8); + } csumfunc; + u32 uid; +}; + +/* So far we just support CAN -> CAN routing and frame modifications. + * + * The internal can_can_gw structure contains data and attributes for + * a CAN -> CAN gateway job. + */ +struct can_can_gw { + struct can_filter filter; + int src_idx; + int dst_idx; +}; + +/* list entry for CAN gateways jobs */ +struct cgw_job { + struct hlist_node list; + struct rcu_head rcu; + u32 handled_frames; + u32 dropped_frames; + u32 deleted_frames; + struct cf_mod mod; + union { + /* CAN frame data source */ + struct net_device *dev; + } src; + union { + /* CAN frame data destination */ + struct net_device *dev; + } dst; + union { + struct can_can_gw ccgw; + /* tbc */ + }; + u8 gwtype; + u8 limit_hops; + u16 flags; +}; + +/* modification functions that are invoked in the hot path in can_can_gw_rcv */ + +#define MODFUNC(func, op) static void func(struct canfd_frame *cf, \ + struct cf_mod *mod) { op ; } + +MODFUNC(mod_and_id, cf->can_id &= mod->modframe.and.can_id) +MODFUNC(mod_and_len, cf->len &= mod->modframe.and.len) +MODFUNC(mod_and_flags, cf->flags &= mod->modframe.and.flags) +MODFUNC(mod_and_data, *(u64 *)cf->data &= *(u64 *)mod->modframe.and.data) +MODFUNC(mod_or_id, cf->can_id |= mod->modframe.or.can_id) +MODFUNC(mod_or_len, cf->len |= mod->modframe.or.len) +MODFUNC(mod_or_flags, cf->flags |= mod->modframe.or.flags) +MODFUNC(mod_or_data, *(u64 *)cf->data |= *(u64 *)mod->modframe.or.data) +MODFUNC(mod_xor_id, cf->can_id ^= mod->modframe.xor.can_id) +MODFUNC(mod_xor_len, cf->len ^= mod->modframe.xor.len) +MODFUNC(mod_xor_flags, cf->flags ^= mod->modframe.xor.flags) +MODFUNC(mod_xor_data, *(u64 *)cf->data ^= *(u64 *)mod->modframe.xor.data) +MODFUNC(mod_set_id, cf->can_id = mod->modframe.set.can_id) +MODFUNC(mod_set_len, cf->len = mod->modframe.set.len) +MODFUNC(mod_set_flags, cf->flags = mod->modframe.set.flags) +MODFUNC(mod_set_data, *(u64 *)cf->data = *(u64 *)mod->modframe.set.data) + +static void mod_and_fddata(struct canfd_frame *cf, struct cf_mod *mod) +{ + int i; + + for (i = 0; i < CANFD_MAX_DLEN; i += 8) + *(u64 *)(cf->data + i) &= *(u64 *)(mod->modframe.and.data + i); +} + +static void mod_or_fddata(struct canfd_frame *cf, struct cf_mod *mod) +{ + int i; + + for (i = 0; i < CANFD_MAX_DLEN; i += 8) + *(u64 *)(cf->data + i) |= *(u64 *)(mod->modframe.or.data + i); +} + +static void mod_xor_fddata(struct canfd_frame *cf, struct cf_mod *mod) +{ + int i; + + for (i = 0; i < CANFD_MAX_DLEN; i += 8) + *(u64 *)(cf->data + i) ^= *(u64 *)(mod->modframe.xor.data + i); +} + +static void mod_set_fddata(struct canfd_frame *cf, struct cf_mod *mod) +{ + memcpy(cf->data, mod->modframe.set.data, CANFD_MAX_DLEN); +} + +/* retrieve valid CC DLC value and store it into 'len' */ +static void mod_retrieve_ccdlc(struct canfd_frame *cf) +{ + struct can_frame *ccf = (struct can_frame *)cf; + + /* len8_dlc is only valid if len == CAN_MAX_DLEN */ + if (ccf->len != CAN_MAX_DLEN) + return; + + /* do we have a valid len8_dlc value from 9 .. 15 ? */ + if (ccf->len8_dlc > CAN_MAX_DLEN && ccf->len8_dlc <= CAN_MAX_RAW_DLC) + ccf->len = ccf->len8_dlc; +} + +/* convert valid CC DLC value in 'len' into struct can_frame elements */ +static void mod_store_ccdlc(struct canfd_frame *cf) +{ + struct can_frame *ccf = (struct can_frame *)cf; + + /* clear potential leftovers */ + ccf->len8_dlc = 0; + + /* plain data length 0 .. 8 - that was easy */ + if (ccf->len <= CAN_MAX_DLEN) + return; + + /* potentially broken values are caught in can_can_gw_rcv() */ + if (ccf->len > CAN_MAX_RAW_DLC) + return; + + /* we have a valid dlc value from 9 .. 15 in ccf->len */ + ccf->len8_dlc = ccf->len; + ccf->len = CAN_MAX_DLEN; +} + +static void mod_and_ccdlc(struct canfd_frame *cf, struct cf_mod *mod) +{ + mod_retrieve_ccdlc(cf); + mod_and_len(cf, mod); + mod_store_ccdlc(cf); +} + +static void mod_or_ccdlc(struct canfd_frame *cf, struct cf_mod *mod) +{ + mod_retrieve_ccdlc(cf); + mod_or_len(cf, mod); + mod_store_ccdlc(cf); +} + +static void mod_xor_ccdlc(struct canfd_frame *cf, struct cf_mod *mod) +{ + mod_retrieve_ccdlc(cf); + mod_xor_len(cf, mod); + mod_store_ccdlc(cf); +} + +static void mod_set_ccdlc(struct canfd_frame *cf, struct cf_mod *mod) +{ + mod_set_len(cf, mod); + mod_store_ccdlc(cf); +} + +static void canframecpy(struct canfd_frame *dst, struct can_frame *src) +{ + /* Copy the struct members separately to ensure that no uninitialized + * data are copied in the 3 bytes hole of the struct. This is needed + * to make easy compares of the data in the struct cf_mod. + */ + + dst->can_id = src->can_id; + dst->len = src->len; + *(u64 *)dst->data = *(u64 *)src->data; +} + +static void canfdframecpy(struct canfd_frame *dst, struct canfd_frame *src) +{ + /* Copy the struct members separately to ensure that no uninitialized + * data are copied in the 2 bytes hole of the struct. This is needed + * to make easy compares of the data in the struct cf_mod. + */ + + dst->can_id = src->can_id; + dst->flags = src->flags; + dst->len = src->len; + memcpy(dst->data, src->data, CANFD_MAX_DLEN); +} + +static int cgw_chk_csum_parms(s8 fr, s8 to, s8 re, struct rtcanmsg *r) +{ + s8 dlen = CAN_MAX_DLEN; + + if (r->flags & CGW_FLAGS_CAN_FD) + dlen = CANFD_MAX_DLEN; + + /* absolute dlc values 0 .. 7 => 0 .. 7, e.g. data [0] + * relative to received dlc -1 .. -8 : + * e.g. for received dlc = 8 + * -1 => index = 7 (data[7]) + * -3 => index = 5 (data[5]) + * -8 => index = 0 (data[0]) + */ + + if (fr >= -dlen && fr < dlen && + to >= -dlen && to < dlen && + re >= -dlen && re < dlen) + return 0; + else + return -EINVAL; +} + +static inline int calc_idx(int idx, int rx_len) +{ + if (idx < 0) + return rx_len + idx; + else + return idx; +} + +static void cgw_csum_xor_rel(struct canfd_frame *cf, struct cgw_csum_xor *xor) +{ + int from = calc_idx(xor->from_idx, cf->len); + int to = calc_idx(xor->to_idx, cf->len); + int res = calc_idx(xor->result_idx, cf->len); + u8 val = xor->init_xor_val; + int i; + + if (from < 0 || to < 0 || res < 0) + return; + + if (from <= to) { + for (i = from; i <= to; i++) + val ^= cf->data[i]; + } else { + for (i = from; i >= to; i--) + val ^= cf->data[i]; + } + + cf->data[res] = val; +} + +static void cgw_csum_xor_pos(struct canfd_frame *cf, struct cgw_csum_xor *xor) +{ + u8 val = xor->init_xor_val; + int i; + + for (i = xor->from_idx; i <= xor->to_idx; i++) + val ^= cf->data[i]; + + cf->data[xor->result_idx] = val; +} + +static void cgw_csum_xor_neg(struct canfd_frame *cf, struct cgw_csum_xor *xor) +{ + u8 val = xor->init_xor_val; + int i; + + for (i = xor->from_idx; i >= xor->to_idx; i--) + val ^= cf->data[i]; + + cf->data[xor->result_idx] = val; +} + +static void cgw_csum_crc8_rel(struct canfd_frame *cf, + struct cgw_csum_crc8 *crc8) +{ + int from = calc_idx(crc8->from_idx, cf->len); + int to = calc_idx(crc8->to_idx, cf->len); + int res = calc_idx(crc8->result_idx, cf->len); + u8 crc = crc8->init_crc_val; + int i; + + if (from < 0 || to < 0 || res < 0) + return; + + if (from <= to) { + for (i = crc8->from_idx; i <= crc8->to_idx; i++) + crc = crc8->crctab[crc ^ cf->data[i]]; + } else { + for (i = crc8->from_idx; i >= crc8->to_idx; i--) + crc = crc8->crctab[crc ^ cf->data[i]]; + } + + switch (crc8->profile) { + case CGW_CRC8PRF_1U8: + crc = crc8->crctab[crc ^ crc8->profile_data[0]]; + break; + + case CGW_CRC8PRF_16U8: + crc = crc8->crctab[crc ^ crc8->profile_data[cf->data[1] & 0xF]]; + break; + + case CGW_CRC8PRF_SFFID_XOR: + crc = crc8->crctab[crc ^ (cf->can_id & 0xFF) ^ + (cf->can_id >> 8 & 0xFF)]; + break; + } + + cf->data[crc8->result_idx] = crc ^ crc8->final_xor_val; +} + +static void cgw_csum_crc8_pos(struct canfd_frame *cf, + struct cgw_csum_crc8 *crc8) +{ + u8 crc = crc8->init_crc_val; + int i; + + for (i = crc8->from_idx; i <= crc8->to_idx; i++) + crc = crc8->crctab[crc ^ cf->data[i]]; + + switch (crc8->profile) { + case CGW_CRC8PRF_1U8: + crc = crc8->crctab[crc ^ crc8->profile_data[0]]; + break; + + case CGW_CRC8PRF_16U8: + crc = crc8->crctab[crc ^ crc8->profile_data[cf->data[1] & 0xF]]; + break; + + case CGW_CRC8PRF_SFFID_XOR: + crc = crc8->crctab[crc ^ (cf->can_id & 0xFF) ^ + (cf->can_id >> 8 & 0xFF)]; + break; + } + + cf->data[crc8->result_idx] = crc ^ crc8->final_xor_val; +} + +static void cgw_csum_crc8_neg(struct canfd_frame *cf, + struct cgw_csum_crc8 *crc8) +{ + u8 crc = crc8->init_crc_val; + int i; + + for (i = crc8->from_idx; i >= crc8->to_idx; i--) + crc = crc8->crctab[crc ^ cf->data[i]]; + + switch (crc8->profile) { + case CGW_CRC8PRF_1U8: + crc = crc8->crctab[crc ^ crc8->profile_data[0]]; + break; + + case CGW_CRC8PRF_16U8: + crc = crc8->crctab[crc ^ crc8->profile_data[cf->data[1] & 0xF]]; + break; + + case CGW_CRC8PRF_SFFID_XOR: + crc = crc8->crctab[crc ^ (cf->can_id & 0xFF) ^ + (cf->can_id >> 8 & 0xFF)]; + break; + } + + cf->data[crc8->result_idx] = crc ^ crc8->final_xor_val; +} + +/* the receive & process & send function */ +static void can_can_gw_rcv(struct sk_buff *skb, void *data) +{ + struct cgw_job *gwj = (struct cgw_job *)data; + struct canfd_frame *cf; + struct sk_buff *nskb; + int modidx = 0; + + /* process strictly Classic CAN or CAN FD frames */ + if (gwj->flags & CGW_FLAGS_CAN_FD) { + if (!can_is_canfd_skb(skb)) + return; + } else { + if (!can_is_can_skb(skb)) + return; + } + + /* Do not handle CAN frames routed more than 'max_hops' times. + * In general we should never catch this delimiter which is intended + * to cover a misconfiguration protection (e.g. circular CAN routes). + * + * The Controller Area Network controllers only accept CAN frames with + * correct CRCs - which are not visible in the controller registers. + * According to skbuff.h documentation the csum_start element for IP + * checksums is undefined/unused when ip_summed == CHECKSUM_UNNECESSARY. + * Only CAN skbs can be processed here which already have this property. + */ + +#define cgw_hops(skb) ((skb)->csum_start) + + BUG_ON(skb->ip_summed != CHECKSUM_UNNECESSARY); + + if (cgw_hops(skb) >= max_hops) { + /* indicate deleted frames due to misconfiguration */ + gwj->deleted_frames++; + return; + } + + if (!(gwj->dst.dev->flags & IFF_UP)) { + gwj->dropped_frames++; + return; + } + + /* is sending the skb back to the incoming interface not allowed? */ + if (!(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK) && + can_skb_prv(skb)->ifindex == gwj->dst.dev->ifindex) + return; + + /* clone the given skb, which has not been done in can_rcv() + * + * When there is at least one modification function activated, + * we need to copy the skb as we want to modify skb->data. + */ + if (gwj->mod.modfunc[0]) + nskb = skb_copy(skb, GFP_ATOMIC); + else + nskb = skb_clone(skb, GFP_ATOMIC); + + if (!nskb) { + gwj->dropped_frames++; + return; + } + + /* put the incremented hop counter in the cloned skb */ + cgw_hops(nskb) = cgw_hops(skb) + 1; + + /* first processing of this CAN frame -> adjust to private hop limit */ + if (gwj->limit_hops && cgw_hops(nskb) == 1) + cgw_hops(nskb) = max_hops - gwj->limit_hops + 1; + + nskb->dev = gwj->dst.dev; + + /* pointer to modifiable CAN frame */ + cf = (struct canfd_frame *)nskb->data; + + /* perform preprocessed modification functions if there are any */ + while (modidx < MAX_MODFUNCTIONS && gwj->mod.modfunc[modidx]) + (*gwj->mod.modfunc[modidx++])(cf, &gwj->mod); + + /* Has the CAN frame been modified? */ + if (modidx) { + /* get available space for the processed CAN frame type */ + int max_len = nskb->len - offsetof(struct canfd_frame, data); + + /* dlc may have changed, make sure it fits to the CAN frame */ + if (cf->len > max_len) { + /* delete frame due to misconfiguration */ + gwj->deleted_frames++; + kfree_skb(nskb); + return; + } + + /* check for checksum updates */ + if (gwj->mod.csumfunc.crc8) + (*gwj->mod.csumfunc.crc8)(cf, &gwj->mod.csum.crc8); + + if (gwj->mod.csumfunc.xor) + (*gwj->mod.csumfunc.xor)(cf, &gwj->mod.csum.xor); + } + + /* clear the skb timestamp if not configured the other way */ + if (!(gwj->flags & CGW_FLAGS_CAN_SRC_TSTAMP)) + nskb->tstamp = 0; + + /* send to netdevice */ + if (can_send(nskb, gwj->flags & CGW_FLAGS_CAN_ECHO)) + gwj->dropped_frames++; + else + gwj->handled_frames++; +} + +static inline int cgw_register_filter(struct net *net, struct cgw_job *gwj) +{ + return can_rx_register(net, gwj->src.dev, gwj->ccgw.filter.can_id, + gwj->ccgw.filter.can_mask, can_can_gw_rcv, + gwj, "gw", NULL); +} + +static inline void cgw_unregister_filter(struct net *net, struct cgw_job *gwj) +{ + can_rx_unregister(net, gwj->src.dev, gwj->ccgw.filter.can_id, + gwj->ccgw.filter.can_mask, can_can_gw_rcv, gwj); +} + +static void cgw_job_free_rcu(struct rcu_head *rcu_head) +{ + struct cgw_job *gwj = container_of(rcu_head, struct cgw_job, rcu); + + kmem_cache_free(cgw_cache, gwj); +} + +static int cgw_notifier(struct notifier_block *nb, + unsigned long msg, void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct net *net = dev_net(dev); + + if (dev->type != ARPHRD_CAN) + return NOTIFY_DONE; + + if (msg == NETDEV_UNREGISTER) { + struct cgw_job *gwj = NULL; + struct hlist_node *nx; + + ASSERT_RTNL(); + + hlist_for_each_entry_safe(gwj, nx, &net->can.cgw_list, list) { + if (gwj->src.dev == dev || gwj->dst.dev == dev) { + hlist_del(&gwj->list); + cgw_unregister_filter(net, gwj); + call_rcu(&gwj->rcu, cgw_job_free_rcu); + } + } + } + + return NOTIFY_DONE; +} + +static int cgw_put_job(struct sk_buff *skb, struct cgw_job *gwj, int type, + u32 pid, u32 seq, int flags) +{ + struct rtcanmsg *rtcan; + struct nlmsghdr *nlh; + + nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtcan), flags); + if (!nlh) + return -EMSGSIZE; + + rtcan = nlmsg_data(nlh); + rtcan->can_family = AF_CAN; + rtcan->gwtype = gwj->gwtype; + rtcan->flags = gwj->flags; + + /* add statistics if available */ + + if (gwj->handled_frames) { + if (nla_put_u32(skb, CGW_HANDLED, gwj->handled_frames) < 0) + goto cancel; + } + + if (gwj->dropped_frames) { + if (nla_put_u32(skb, CGW_DROPPED, gwj->dropped_frames) < 0) + goto cancel; + } + + if (gwj->deleted_frames) { + if (nla_put_u32(skb, CGW_DELETED, gwj->deleted_frames) < 0) + goto cancel; + } + + /* check non default settings of attributes */ + + if (gwj->limit_hops) { + if (nla_put_u8(skb, CGW_LIM_HOPS, gwj->limit_hops) < 0) + goto cancel; + } + + if (gwj->flags & CGW_FLAGS_CAN_FD) { + struct cgw_fdframe_mod mb; + + if (gwj->mod.modtype.and) { + memcpy(&mb.cf, &gwj->mod.modframe.and, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.and; + if (nla_put(skb, CGW_FDMOD_AND, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.or) { + memcpy(&mb.cf, &gwj->mod.modframe.or, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.or; + if (nla_put(skb, CGW_FDMOD_OR, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.xor) { + memcpy(&mb.cf, &gwj->mod.modframe.xor, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.xor; + if (nla_put(skb, CGW_FDMOD_XOR, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.set) { + memcpy(&mb.cf, &gwj->mod.modframe.set, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.set; + if (nla_put(skb, CGW_FDMOD_SET, sizeof(mb), &mb) < 0) + goto cancel; + } + } else { + struct cgw_frame_mod mb; + + if (gwj->mod.modtype.and) { + memcpy(&mb.cf, &gwj->mod.modframe.and, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.and; + if (nla_put(skb, CGW_MOD_AND, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.or) { + memcpy(&mb.cf, &gwj->mod.modframe.or, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.or; + if (nla_put(skb, CGW_MOD_OR, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.xor) { + memcpy(&mb.cf, &gwj->mod.modframe.xor, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.xor; + if (nla_put(skb, CGW_MOD_XOR, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.set) { + memcpy(&mb.cf, &gwj->mod.modframe.set, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.set; + if (nla_put(skb, CGW_MOD_SET, sizeof(mb), &mb) < 0) + goto cancel; + } + } + + if (gwj->mod.uid) { + if (nla_put_u32(skb, CGW_MOD_UID, gwj->mod.uid) < 0) + goto cancel; + } + + if (gwj->mod.csumfunc.crc8) { + if (nla_put(skb, CGW_CS_CRC8, CGW_CS_CRC8_LEN, + &gwj->mod.csum.crc8) < 0) + goto cancel; + } + + if (gwj->mod.csumfunc.xor) { + if (nla_put(skb, CGW_CS_XOR, CGW_CS_XOR_LEN, + &gwj->mod.csum.xor) < 0) + goto cancel; + } + + if (gwj->gwtype == CGW_TYPE_CAN_CAN) { + if (gwj->ccgw.filter.can_id || gwj->ccgw.filter.can_mask) { + if (nla_put(skb, CGW_FILTER, sizeof(struct can_filter), + &gwj->ccgw.filter) < 0) + goto cancel; + } + + if (nla_put_u32(skb, CGW_SRC_IF, gwj->ccgw.src_idx) < 0) + goto cancel; + + if (nla_put_u32(skb, CGW_DST_IF, gwj->ccgw.dst_idx) < 0) + goto cancel; + } + + nlmsg_end(skb, nlh); + return 0; + +cancel: + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; +} + +/* Dump information about all CAN gateway jobs, in response to RTM_GETROUTE */ +static int cgw_dump_jobs(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct net *net = sock_net(skb->sk); + struct cgw_job *gwj = NULL; + int idx = 0; + int s_idx = cb->args[0]; + + rcu_read_lock(); + hlist_for_each_entry_rcu(gwj, &net->can.cgw_list, list) { + if (idx < s_idx) + goto cont; + + if (cgw_put_job(skb, gwj, RTM_NEWROUTE, + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI) < 0) + break; +cont: + idx++; + } + rcu_read_unlock(); + + cb->args[0] = idx; + + return skb->len; +} + +static const struct nla_policy cgw_policy[CGW_MAX + 1] = { + [CGW_MOD_AND] = { .len = sizeof(struct cgw_frame_mod) }, + [CGW_MOD_OR] = { .len = sizeof(struct cgw_frame_mod) }, + [CGW_MOD_XOR] = { .len = sizeof(struct cgw_frame_mod) }, + [CGW_MOD_SET] = { .len = sizeof(struct cgw_frame_mod) }, + [CGW_CS_XOR] = { .len = sizeof(struct cgw_csum_xor) }, + [CGW_CS_CRC8] = { .len = sizeof(struct cgw_csum_crc8) }, + [CGW_SRC_IF] = { .type = NLA_U32 }, + [CGW_DST_IF] = { .type = NLA_U32 }, + [CGW_FILTER] = { .len = sizeof(struct can_filter) }, + [CGW_LIM_HOPS] = { .type = NLA_U8 }, + [CGW_MOD_UID] = { .type = NLA_U32 }, + [CGW_FDMOD_AND] = { .len = sizeof(struct cgw_fdframe_mod) }, + [CGW_FDMOD_OR] = { .len = sizeof(struct cgw_fdframe_mod) }, + [CGW_FDMOD_XOR] = { .len = sizeof(struct cgw_fdframe_mod) }, + [CGW_FDMOD_SET] = { .len = sizeof(struct cgw_fdframe_mod) }, +}; + +/* check for common and gwtype specific attributes */ +static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, + u8 gwtype, void *gwtypeattr, u8 *limhops) +{ + struct nlattr *tb[CGW_MAX + 1]; + struct rtcanmsg *r = nlmsg_data(nlh); + int modidx = 0; + int err = 0; + + /* initialize modification & checksum data space */ + memset(mod, 0, sizeof(*mod)); + + err = nlmsg_parse_deprecated(nlh, sizeof(struct rtcanmsg), tb, + CGW_MAX, cgw_policy, NULL); + if (err < 0) + return err; + + if (tb[CGW_LIM_HOPS]) { + *limhops = nla_get_u8(tb[CGW_LIM_HOPS]); + + if (*limhops < 1 || *limhops > max_hops) + return -EINVAL; + } + + /* check for AND/OR/XOR/SET modifications */ + if (r->flags & CGW_FLAGS_CAN_FD) { + struct cgw_fdframe_mod mb; + + if (tb[CGW_FDMOD_AND]) { + nla_memcpy(&mb, tb[CGW_FDMOD_AND], CGW_FDMODATTR_LEN); + + canfdframecpy(&mod->modframe.and, &mb.cf); + mod->modtype.and = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_and_id; + + if (mb.modtype & CGW_MOD_LEN) + mod->modfunc[modidx++] = mod_and_len; + + if (mb.modtype & CGW_MOD_FLAGS) + mod->modfunc[modidx++] = mod_and_flags; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_and_fddata; + } + + if (tb[CGW_FDMOD_OR]) { + nla_memcpy(&mb, tb[CGW_FDMOD_OR], CGW_FDMODATTR_LEN); + + canfdframecpy(&mod->modframe.or, &mb.cf); + mod->modtype.or = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_or_id; + + if (mb.modtype & CGW_MOD_LEN) + mod->modfunc[modidx++] = mod_or_len; + + if (mb.modtype & CGW_MOD_FLAGS) + mod->modfunc[modidx++] = mod_or_flags; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_or_fddata; + } + + if (tb[CGW_FDMOD_XOR]) { + nla_memcpy(&mb, tb[CGW_FDMOD_XOR], CGW_FDMODATTR_LEN); + + canfdframecpy(&mod->modframe.xor, &mb.cf); + mod->modtype.xor = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_xor_id; + + if (mb.modtype & CGW_MOD_LEN) + mod->modfunc[modidx++] = mod_xor_len; + + if (mb.modtype & CGW_MOD_FLAGS) + mod->modfunc[modidx++] = mod_xor_flags; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_xor_fddata; + } + + if (tb[CGW_FDMOD_SET]) { + nla_memcpy(&mb, tb[CGW_FDMOD_SET], CGW_FDMODATTR_LEN); + + canfdframecpy(&mod->modframe.set, &mb.cf); + mod->modtype.set = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_set_id; + + if (mb.modtype & CGW_MOD_LEN) + mod->modfunc[modidx++] = mod_set_len; + + if (mb.modtype & CGW_MOD_FLAGS) + mod->modfunc[modidx++] = mod_set_flags; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_set_fddata; + } + } else { + struct cgw_frame_mod mb; + + if (tb[CGW_MOD_AND]) { + nla_memcpy(&mb, tb[CGW_MOD_AND], CGW_MODATTR_LEN); + + canframecpy(&mod->modframe.and, &mb.cf); + mod->modtype.and = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_and_id; + + if (mb.modtype & CGW_MOD_DLC) + mod->modfunc[modidx++] = mod_and_ccdlc; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_and_data; + } + + if (tb[CGW_MOD_OR]) { + nla_memcpy(&mb, tb[CGW_MOD_OR], CGW_MODATTR_LEN); + + canframecpy(&mod->modframe.or, &mb.cf); + mod->modtype.or = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_or_id; + + if (mb.modtype & CGW_MOD_DLC) + mod->modfunc[modidx++] = mod_or_ccdlc; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_or_data; + } + + if (tb[CGW_MOD_XOR]) { + nla_memcpy(&mb, tb[CGW_MOD_XOR], CGW_MODATTR_LEN); + + canframecpy(&mod->modframe.xor, &mb.cf); + mod->modtype.xor = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_xor_id; + + if (mb.modtype & CGW_MOD_DLC) + mod->modfunc[modidx++] = mod_xor_ccdlc; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_xor_data; + } + + if (tb[CGW_MOD_SET]) { + nla_memcpy(&mb, tb[CGW_MOD_SET], CGW_MODATTR_LEN); + + canframecpy(&mod->modframe.set, &mb.cf); + mod->modtype.set = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_set_id; + + if (mb.modtype & CGW_MOD_DLC) + mod->modfunc[modidx++] = mod_set_ccdlc; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_set_data; + } + } + + /* check for checksum operations after CAN frame modifications */ + if (modidx) { + if (tb[CGW_CS_CRC8]) { + struct cgw_csum_crc8 *c = nla_data(tb[CGW_CS_CRC8]); + + err = cgw_chk_csum_parms(c->from_idx, c->to_idx, + c->result_idx, r); + if (err) + return err; + + nla_memcpy(&mod->csum.crc8, tb[CGW_CS_CRC8], + CGW_CS_CRC8_LEN); + + /* select dedicated processing function to reduce + * runtime operations in receive hot path. + */ + if (c->from_idx < 0 || c->to_idx < 0 || + c->result_idx < 0) + mod->csumfunc.crc8 = cgw_csum_crc8_rel; + else if (c->from_idx <= c->to_idx) + mod->csumfunc.crc8 = cgw_csum_crc8_pos; + else + mod->csumfunc.crc8 = cgw_csum_crc8_neg; + } + + if (tb[CGW_CS_XOR]) { + struct cgw_csum_xor *c = nla_data(tb[CGW_CS_XOR]); + + err = cgw_chk_csum_parms(c->from_idx, c->to_idx, + c->result_idx, r); + if (err) + return err; + + nla_memcpy(&mod->csum.xor, tb[CGW_CS_XOR], + CGW_CS_XOR_LEN); + + /* select dedicated processing function to reduce + * runtime operations in receive hot path. + */ + if (c->from_idx < 0 || c->to_idx < 0 || + c->result_idx < 0) + mod->csumfunc.xor = cgw_csum_xor_rel; + else if (c->from_idx <= c->to_idx) + mod->csumfunc.xor = cgw_csum_xor_pos; + else + mod->csumfunc.xor = cgw_csum_xor_neg; + } + + if (tb[CGW_MOD_UID]) + nla_memcpy(&mod->uid, tb[CGW_MOD_UID], sizeof(u32)); + } + + if (gwtype == CGW_TYPE_CAN_CAN) { + /* check CGW_TYPE_CAN_CAN specific attributes */ + struct can_can_gw *ccgw = (struct can_can_gw *)gwtypeattr; + + memset(ccgw, 0, sizeof(*ccgw)); + + /* check for can_filter in attributes */ + if (tb[CGW_FILTER]) + nla_memcpy(&ccgw->filter, tb[CGW_FILTER], + sizeof(struct can_filter)); + + err = -ENODEV; + + /* specifying two interfaces is mandatory */ + if (!tb[CGW_SRC_IF] || !tb[CGW_DST_IF]) + return err; + + ccgw->src_idx = nla_get_u32(tb[CGW_SRC_IF]); + ccgw->dst_idx = nla_get_u32(tb[CGW_DST_IF]); + + /* both indices set to 0 for flushing all routing entries */ + if (!ccgw->src_idx && !ccgw->dst_idx) + return 0; + + /* only one index set to 0 is an error */ + if (!ccgw->src_idx || !ccgw->dst_idx) + return err; + } + + /* add the checks for other gwtypes here */ + + return 0; +} + +static int cgw_create_job(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) +{ + struct net *net = sock_net(skb->sk); + struct rtcanmsg *r; + struct cgw_job *gwj; + struct cf_mod mod; + struct can_can_gw ccgw; + u8 limhops = 0; + int err = 0; + + if (!netlink_capable(skb, CAP_NET_ADMIN)) + return -EPERM; + + if (nlmsg_len(nlh) < sizeof(*r)) + return -EINVAL; + + r = nlmsg_data(nlh); + if (r->can_family != AF_CAN) + return -EPFNOSUPPORT; + + /* so far we only support CAN -> CAN routings */ + if (r->gwtype != CGW_TYPE_CAN_CAN) + return -EINVAL; + + err = cgw_parse_attr(nlh, &mod, CGW_TYPE_CAN_CAN, &ccgw, &limhops); + if (err < 0) + return err; + + if (mod.uid) { + ASSERT_RTNL(); + + /* check for updating an existing job with identical uid */ + hlist_for_each_entry(gwj, &net->can.cgw_list, list) { + if (gwj->mod.uid != mod.uid) + continue; + + /* interfaces & filters must be identical */ + if (memcmp(&gwj->ccgw, &ccgw, sizeof(ccgw))) + return -EINVAL; + + /* update modifications with disabled softirq & quit */ + local_bh_disable(); + memcpy(&gwj->mod, &mod, sizeof(mod)); + local_bh_enable(); + return 0; + } + } + + /* ifindex == 0 is not allowed for job creation */ + if (!ccgw.src_idx || !ccgw.dst_idx) + return -ENODEV; + + gwj = kmem_cache_alloc(cgw_cache, GFP_KERNEL); + if (!gwj) + return -ENOMEM; + + gwj->handled_frames = 0; + gwj->dropped_frames = 0; + gwj->deleted_frames = 0; + gwj->flags = r->flags; + gwj->gwtype = r->gwtype; + gwj->limit_hops = limhops; + + /* insert already parsed information */ + memcpy(&gwj->mod, &mod, sizeof(mod)); + memcpy(&gwj->ccgw, &ccgw, sizeof(ccgw)); + + err = -ENODEV; + + gwj->src.dev = __dev_get_by_index(net, gwj->ccgw.src_idx); + + if (!gwj->src.dev) + goto out; + + if (gwj->src.dev->type != ARPHRD_CAN) + goto out; + + gwj->dst.dev = __dev_get_by_index(net, gwj->ccgw.dst_idx); + + if (!gwj->dst.dev) + goto out; + + if (gwj->dst.dev->type != ARPHRD_CAN) + goto out; + + /* is sending the skb back to the incoming interface intended? */ + if (gwj->src.dev == gwj->dst.dev && + !(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK)) { + err = -EINVAL; + goto out; + } + + ASSERT_RTNL(); + + err = cgw_register_filter(net, gwj); + if (!err) + hlist_add_head_rcu(&gwj->list, &net->can.cgw_list); +out: + if (err) + kmem_cache_free(cgw_cache, gwj); + + return err; +} + +static void cgw_remove_all_jobs(struct net *net) +{ + struct cgw_job *gwj = NULL; + struct hlist_node *nx; + + ASSERT_RTNL(); + + hlist_for_each_entry_safe(gwj, nx, &net->can.cgw_list, list) { + hlist_del(&gwj->list); + cgw_unregister_filter(net, gwj); + call_rcu(&gwj->rcu, cgw_job_free_rcu); + } +} + +static int cgw_remove_job(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) +{ + struct net *net = sock_net(skb->sk); + struct cgw_job *gwj = NULL; + struct hlist_node *nx; + struct rtcanmsg *r; + struct cf_mod mod; + struct can_can_gw ccgw; + u8 limhops = 0; + int err = 0; + + if (!netlink_capable(skb, CAP_NET_ADMIN)) + return -EPERM; + + if (nlmsg_len(nlh) < sizeof(*r)) + return -EINVAL; + + r = nlmsg_data(nlh); + if (r->can_family != AF_CAN) + return -EPFNOSUPPORT; + + /* so far we only support CAN -> CAN routings */ + if (r->gwtype != CGW_TYPE_CAN_CAN) + return -EINVAL; + + err = cgw_parse_attr(nlh, &mod, CGW_TYPE_CAN_CAN, &ccgw, &limhops); + if (err < 0) + return err; + + /* two interface indices both set to 0 => remove all entries */ + if (!ccgw.src_idx && !ccgw.dst_idx) { + cgw_remove_all_jobs(net); + return 0; + } + + err = -EINVAL; + + ASSERT_RTNL(); + + /* remove only the first matching entry */ + hlist_for_each_entry_safe(gwj, nx, &net->can.cgw_list, list) { + if (gwj->flags != r->flags) + continue; + + if (gwj->limit_hops != limhops) + continue; + + /* we have a match when uid is enabled and identical */ + if (gwj->mod.uid || mod.uid) { + if (gwj->mod.uid != mod.uid) + continue; + } else { + /* no uid => check for identical modifications */ + if (memcmp(&gwj->mod, &mod, sizeof(mod))) + continue; + } + + /* if (r->gwtype == CGW_TYPE_CAN_CAN) - is made sure here */ + if (memcmp(&gwj->ccgw, &ccgw, sizeof(ccgw))) + continue; + + hlist_del(&gwj->list); + cgw_unregister_filter(net, gwj); + call_rcu(&gwj->rcu, cgw_job_free_rcu); + err = 0; + break; + } + + return err; +} + +static int __net_init cangw_pernet_init(struct net *net) +{ + INIT_HLIST_HEAD(&net->can.cgw_list); + return 0; +} + +static void __net_exit cangw_pernet_exit_batch(struct list_head *net_list) +{ + struct net *net; + + rtnl_lock(); + list_for_each_entry(net, net_list, exit_list) + cgw_remove_all_jobs(net); + rtnl_unlock(); +} + +static struct pernet_operations cangw_pernet_ops = { + .init = cangw_pernet_init, + .exit_batch = cangw_pernet_exit_batch, +}; + +static __init int cgw_module_init(void) +{ + int ret; + + /* sanitize given module parameter */ + max_hops = clamp_t(unsigned int, max_hops, CGW_MIN_HOPS, CGW_MAX_HOPS); + + pr_info("can: netlink gateway - max_hops=%d\n", max_hops); + + ret = register_pernet_subsys(&cangw_pernet_ops); + if (ret) + return ret; + + ret = -ENOMEM; + cgw_cache = kmem_cache_create("can_gw", sizeof(struct cgw_job), + 0, 0, NULL); + if (!cgw_cache) + goto out_cache_create; + + /* set notifier */ + notifier.notifier_call = cgw_notifier; + ret = register_netdevice_notifier(¬ifier); + if (ret) + goto out_register_notifier; + + ret = rtnl_register_module(THIS_MODULE, PF_CAN, RTM_GETROUTE, + NULL, cgw_dump_jobs, 0); + if (ret) + goto out_rtnl_register1; + + ret = rtnl_register_module(THIS_MODULE, PF_CAN, RTM_NEWROUTE, + cgw_create_job, NULL, 0); + if (ret) + goto out_rtnl_register2; + ret = rtnl_register_module(THIS_MODULE, PF_CAN, RTM_DELROUTE, + cgw_remove_job, NULL, 0); + if (ret) + goto out_rtnl_register3; + + return 0; + +out_rtnl_register3: + rtnl_unregister(PF_CAN, RTM_NEWROUTE); +out_rtnl_register2: + rtnl_unregister(PF_CAN, RTM_GETROUTE); +out_rtnl_register1: + unregister_netdevice_notifier(¬ifier); +out_register_notifier: + kmem_cache_destroy(cgw_cache); +out_cache_create: + unregister_pernet_subsys(&cangw_pernet_ops); + + return ret; +} + +static __exit void cgw_module_exit(void) +{ + rtnl_unregister_all(PF_CAN); + + unregister_netdevice_notifier(¬ifier); + + unregister_pernet_subsys(&cangw_pernet_ops); + rcu_barrier(); /* Wait for completion of call_rcu()'s */ + + kmem_cache_destroy(cgw_cache); +} + +module_init(cgw_module_init); +module_exit(cgw_module_exit); diff --git a/net/can/isotp.c b/net/can/isotp.c new file mode 100644 index 000000000..d1c6f206f --- /dev/null +++ b/net/can/isotp.c @@ -0,0 +1,1737 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* isotp.c - ISO 15765-2 CAN transport protocol for protocol family CAN + * + * This implementation does not provide ISO-TP specific return values to the + * userspace. + * + * - RX path timeout of data reception leads to -ETIMEDOUT + * - RX path SN mismatch leads to -EILSEQ + * - RX path data reception with wrong padding leads to -EBADMSG + * - TX path flowcontrol reception timeout leads to -ECOMM + * - TX path flowcontrol reception overflow leads to -EMSGSIZE + * - TX path flowcontrol reception with wrong layout/padding leads to -EBADMSG + * - when a transfer (tx) is on the run the next write() blocks until it's done + * - use CAN_ISOTP_WAIT_TX_DONE flag to block the caller until the PDU is sent + * - as we have static buffers the check whether the PDU fits into the buffer + * is done at FF reception time (no support for sending 'wait frames') + * + * Copyright (c) 2020 Volkswagen Group Electronic Research + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Volkswagen nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * Alternatively, provided that this notice is retained in full, this + * software may be distributed under the terms of the GNU General + * Public License ("GPL") version 2, in which case the provisions of the + * GPL apply INSTEAD OF those given above. + * + * The provided data structures and external interfaces from this code + * are not restricted to be used by modules with a GPL compatible license. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/spinlock.h> +#include <linux/hrtimer.h> +#include <linux/wait.h> +#include <linux/uio.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/socket.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/can.h> +#include <linux/can/core.h> +#include <linux/can/skb.h> +#include <linux/can/isotp.h> +#include <linux/slab.h> +#include <net/sock.h> +#include <net/net_namespace.h> + +MODULE_DESCRIPTION("PF_CAN isotp 15765-2:2016 protocol"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Oliver Hartkopp <socketcan@hartkopp.net>"); +MODULE_ALIAS("can-proto-6"); + +#define ISOTP_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.tp) + +#define SINGLE_MASK(id) (((id) & CAN_EFF_FLAG) ? \ + (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \ + (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG)) + +/* ISO 15765-2:2016 supports more than 4095 byte per ISO PDU as the FF_DL can + * take full 32 bit values (4 Gbyte). We would need some good concept to handle + * this between user space and kernel space. For now set the static buffer to + * something about 8 kbyte to be able to test this new functionality. + */ +#define DEFAULT_MAX_PDU_SIZE 8300 + +/* maximum PDU size before ISO 15765-2:2016 extension was 4095 */ +#define MAX_12BIT_PDU_SIZE 4095 + +/* limit the isotp pdu size from the optional module parameter to 1MByte */ +#define MAX_PDU_SIZE (1025 * 1024U) + +static unsigned int max_pdu_size __read_mostly = DEFAULT_MAX_PDU_SIZE; +module_param(max_pdu_size, uint, 0444); +MODULE_PARM_DESC(max_pdu_size, "maximum isotp pdu size (default " + __stringify(DEFAULT_MAX_PDU_SIZE) ")"); + +/* N_PCI type values in bits 7-4 of N_PCI bytes */ +#define N_PCI_SF 0x00 /* single frame */ +#define N_PCI_FF 0x10 /* first frame */ +#define N_PCI_CF 0x20 /* consecutive frame */ +#define N_PCI_FC 0x30 /* flow control */ + +#define N_PCI_SZ 1 /* size of the PCI byte #1 */ +#define SF_PCI_SZ4 1 /* size of SingleFrame PCI including 4 bit SF_DL */ +#define SF_PCI_SZ8 2 /* size of SingleFrame PCI including 8 bit SF_DL */ +#define FF_PCI_SZ12 2 /* size of FirstFrame PCI including 12 bit FF_DL */ +#define FF_PCI_SZ32 6 /* size of FirstFrame PCI including 32 bit FF_DL */ +#define FC_CONTENT_SZ 3 /* flow control content size in byte (FS/BS/STmin) */ + +#define ISOTP_CHECK_PADDING (CAN_ISOTP_CHK_PAD_LEN | CAN_ISOTP_CHK_PAD_DATA) +#define ISOTP_ALL_BC_FLAGS (CAN_ISOTP_SF_BROADCAST | CAN_ISOTP_CF_BROADCAST) + +/* Flow Status given in FC frame */ +#define ISOTP_FC_CTS 0 /* clear to send */ +#define ISOTP_FC_WT 1 /* wait */ +#define ISOTP_FC_OVFLW 2 /* overflow */ + +#define ISOTP_FC_TIMEOUT 1 /* 1 sec */ +#define ISOTP_ECHO_TIMEOUT 2 /* 2 secs */ + +enum { + ISOTP_IDLE = 0, + ISOTP_WAIT_FIRST_FC, + ISOTP_WAIT_FC, + ISOTP_WAIT_DATA, + ISOTP_SENDING, + ISOTP_SHUTDOWN, +}; + +struct tpcon { + u8 *buf; + unsigned int buflen; + unsigned int len; + unsigned int idx; + u32 state; + u8 bs; + u8 sn; + u8 ll_dl; + u8 sbuf[DEFAULT_MAX_PDU_SIZE]; +}; + +struct isotp_sock { + struct sock sk; + int bound; + int ifindex; + canid_t txid; + canid_t rxid; + ktime_t tx_gap; + ktime_t lastrxcf_tstamp; + struct hrtimer rxtimer, txtimer, txfrtimer; + struct can_isotp_options opt; + struct can_isotp_fc_options rxfc, txfc; + struct can_isotp_ll_options ll; + u32 frame_txtime; + u32 force_tx_stmin; + u32 force_rx_stmin; + u32 cfecho; /* consecutive frame echo tag */ + struct tpcon rx, tx; + struct list_head notifier; + wait_queue_head_t wait; + spinlock_t rx_lock; /* protect single thread state machine */ +}; + +static LIST_HEAD(isotp_notifier_list); +static DEFINE_SPINLOCK(isotp_notifier_lock); +static struct isotp_sock *isotp_busy_notifier; + +static inline struct isotp_sock *isotp_sk(const struct sock *sk) +{ + return (struct isotp_sock *)sk; +} + +static u32 isotp_bc_flags(struct isotp_sock *so) +{ + return so->opt.flags & ISOTP_ALL_BC_FLAGS; +} + +static bool isotp_register_rxid(struct isotp_sock *so) +{ + /* no broadcast modes => register rx_id for FC frame reception */ + return (isotp_bc_flags(so) == 0); +} + +static enum hrtimer_restart isotp_rx_timer_handler(struct hrtimer *hrtimer) +{ + struct isotp_sock *so = container_of(hrtimer, struct isotp_sock, + rxtimer); + struct sock *sk = &so->sk; + + if (so->rx.state == ISOTP_WAIT_DATA) { + /* we did not get new data frames in time */ + + /* report 'connection timed out' */ + sk->sk_err = ETIMEDOUT; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + + /* reset rx state */ + so->rx.state = ISOTP_IDLE; + } + + return HRTIMER_NORESTART; +} + +static int isotp_send_fc(struct sock *sk, int ae, u8 flowstatus) +{ + struct net_device *dev; + struct sk_buff *nskb; + struct canfd_frame *ncf; + struct isotp_sock *so = isotp_sk(sk); + int can_send_ret; + + nskb = alloc_skb(so->ll.mtu + sizeof(struct can_skb_priv), gfp_any()); + if (!nskb) + return 1; + + dev = dev_get_by_index(sock_net(sk), so->ifindex); + if (!dev) { + kfree_skb(nskb); + return 1; + } + + can_skb_reserve(nskb); + can_skb_prv(nskb)->ifindex = dev->ifindex; + can_skb_prv(nskb)->skbcnt = 0; + + nskb->dev = dev; + can_skb_set_owner(nskb, sk); + ncf = (struct canfd_frame *)nskb->data; + skb_put_zero(nskb, so->ll.mtu); + + /* create & send flow control reply */ + ncf->can_id = so->txid; + + if (so->opt.flags & CAN_ISOTP_TX_PADDING) { + memset(ncf->data, so->opt.txpad_content, CAN_MAX_DLEN); + ncf->len = CAN_MAX_DLEN; + } else { + ncf->len = ae + FC_CONTENT_SZ; + } + + ncf->data[ae] = N_PCI_FC | flowstatus; + ncf->data[ae + 1] = so->rxfc.bs; + ncf->data[ae + 2] = so->rxfc.stmin; + + if (ae) + ncf->data[0] = so->opt.ext_address; + + ncf->flags = so->ll.tx_flags; + + can_send_ret = can_send(nskb, 1); + if (can_send_ret) + pr_notice_once("can-isotp: %s: can_send_ret %pe\n", + __func__, ERR_PTR(can_send_ret)); + + dev_put(dev); + + /* reset blocksize counter */ + so->rx.bs = 0; + + /* reset last CF frame rx timestamp for rx stmin enforcement */ + so->lastrxcf_tstamp = ktime_set(0, 0); + + /* start rx timeout watchdog */ + hrtimer_start(&so->rxtimer, ktime_set(ISOTP_FC_TIMEOUT, 0), + HRTIMER_MODE_REL_SOFT); + return 0; +} + +static void isotp_rcv_skb(struct sk_buff *skb, struct sock *sk) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)skb->cb; + + BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can)); + + memset(addr, 0, sizeof(*addr)); + addr->can_family = AF_CAN; + addr->can_ifindex = skb->dev->ifindex; + + if (sock_queue_rcv_skb(sk, skb) < 0) + kfree_skb(skb); +} + +static u8 padlen(u8 datalen) +{ + static const u8 plen[] = { + 8, 8, 8, 8, 8, 8, 8, 8, 8, /* 0 - 8 */ + 12, 12, 12, 12, /* 9 - 12 */ + 16, 16, 16, 16, /* 13 - 16 */ + 20, 20, 20, 20, /* 17 - 20 */ + 24, 24, 24, 24, /* 21 - 24 */ + 32, 32, 32, 32, 32, 32, 32, 32, /* 25 - 32 */ + 48, 48, 48, 48, 48, 48, 48, 48, /* 33 - 40 */ + 48, 48, 48, 48, 48, 48, 48, 48 /* 41 - 48 */ + }; + + if (datalen > 48) + return 64; + + return plen[datalen]; +} + +/* check for length optimization and return 1/true when the check fails */ +static int check_optimized(struct canfd_frame *cf, int start_index) +{ + /* for CAN_DL <= 8 the start_index is equal to the CAN_DL as the + * padding would start at this point. E.g. if the padding would + * start at cf.data[7] cf->len has to be 7 to be optimal. + * Note: The data[] index starts with zero. + */ + if (cf->len <= CAN_MAX_DLEN) + return (cf->len != start_index); + + /* This relation is also valid in the non-linear DLC range, where + * we need to take care of the minimal next possible CAN_DL. + * The correct check would be (padlen(cf->len) != padlen(start_index)). + * But as cf->len can only take discrete values from 12, .., 64 at this + * point the padlen(cf->len) is always equal to cf->len. + */ + return (cf->len != padlen(start_index)); +} + +/* check padding and return 1/true when the check fails */ +static int check_pad(struct isotp_sock *so, struct canfd_frame *cf, + int start_index, u8 content) +{ + int i; + + /* no RX_PADDING value => check length of optimized frame length */ + if (!(so->opt.flags & CAN_ISOTP_RX_PADDING)) { + if (so->opt.flags & CAN_ISOTP_CHK_PAD_LEN) + return check_optimized(cf, start_index); + + /* no valid test against empty value => ignore frame */ + return 1; + } + + /* check datalength of correctly padded CAN frame */ + if ((so->opt.flags & CAN_ISOTP_CHK_PAD_LEN) && + cf->len != padlen(cf->len)) + return 1; + + /* check padding content */ + if (so->opt.flags & CAN_ISOTP_CHK_PAD_DATA) { + for (i = start_index; i < cf->len; i++) + if (cf->data[i] != content) + return 1; + } + return 0; +} + +static void isotp_send_cframe(struct isotp_sock *so); + +static int isotp_rcv_fc(struct isotp_sock *so, struct canfd_frame *cf, int ae) +{ + struct sock *sk = &so->sk; + + if (so->tx.state != ISOTP_WAIT_FC && + so->tx.state != ISOTP_WAIT_FIRST_FC) + return 0; + + hrtimer_cancel(&so->txtimer); + + if ((cf->len < ae + FC_CONTENT_SZ) || + ((so->opt.flags & ISOTP_CHECK_PADDING) && + check_pad(so, cf, ae + FC_CONTENT_SZ, so->opt.rxpad_content))) { + /* malformed PDU - report 'not a data message' */ + sk->sk_err = EBADMSG; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + + so->tx.state = ISOTP_IDLE; + wake_up_interruptible(&so->wait); + return 1; + } + + /* get communication parameters only from the first FC frame */ + if (so->tx.state == ISOTP_WAIT_FIRST_FC) { + so->txfc.bs = cf->data[ae + 1]; + so->txfc.stmin = cf->data[ae + 2]; + + /* fix wrong STmin values according spec */ + if (so->txfc.stmin > 0x7F && + (so->txfc.stmin < 0xF1 || so->txfc.stmin > 0xF9)) + so->txfc.stmin = 0x7F; + + so->tx_gap = ktime_set(0, 0); + /* add transmission time for CAN frame N_As */ + so->tx_gap = ktime_add_ns(so->tx_gap, so->frame_txtime); + /* add waiting time for consecutive frames N_Cs */ + if (so->opt.flags & CAN_ISOTP_FORCE_TXSTMIN) + so->tx_gap = ktime_add_ns(so->tx_gap, + so->force_tx_stmin); + else if (so->txfc.stmin < 0x80) + so->tx_gap = ktime_add_ns(so->tx_gap, + so->txfc.stmin * 1000000); + else + so->tx_gap = ktime_add_ns(so->tx_gap, + (so->txfc.stmin - 0xF0) + * 100000); + so->tx.state = ISOTP_WAIT_FC; + } + + switch (cf->data[ae] & 0x0F) { + case ISOTP_FC_CTS: + so->tx.bs = 0; + so->tx.state = ISOTP_SENDING; + /* send CF frame and enable echo timeout handling */ + hrtimer_start(&so->txtimer, ktime_set(ISOTP_ECHO_TIMEOUT, 0), + HRTIMER_MODE_REL_SOFT); + isotp_send_cframe(so); + break; + + case ISOTP_FC_WT: + /* start timer to wait for next FC frame */ + hrtimer_start(&so->txtimer, ktime_set(ISOTP_FC_TIMEOUT, 0), + HRTIMER_MODE_REL_SOFT); + break; + + case ISOTP_FC_OVFLW: + /* overflow on receiver side - report 'message too long' */ + sk->sk_err = EMSGSIZE; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + fallthrough; + + default: + /* stop this tx job */ + so->tx.state = ISOTP_IDLE; + wake_up_interruptible(&so->wait); + } + return 0; +} + +static int isotp_rcv_sf(struct sock *sk, struct canfd_frame *cf, int pcilen, + struct sk_buff *skb, int len) +{ + struct isotp_sock *so = isotp_sk(sk); + struct sk_buff *nskb; + + hrtimer_cancel(&so->rxtimer); + so->rx.state = ISOTP_IDLE; + + if (!len || len > cf->len - pcilen) + return 1; + + if ((so->opt.flags & ISOTP_CHECK_PADDING) && + check_pad(so, cf, pcilen + len, so->opt.rxpad_content)) { + /* malformed PDU - report 'not a data message' */ + sk->sk_err = EBADMSG; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + return 1; + } + + nskb = alloc_skb(len, gfp_any()); + if (!nskb) + return 1; + + memcpy(skb_put(nskb, len), &cf->data[pcilen], len); + + nskb->tstamp = skb->tstamp; + nskb->dev = skb->dev; + isotp_rcv_skb(nskb, sk); + return 0; +} + +static int isotp_rcv_ff(struct sock *sk, struct canfd_frame *cf, int ae) +{ + struct isotp_sock *so = isotp_sk(sk); + int i; + int off; + int ff_pci_sz; + + hrtimer_cancel(&so->rxtimer); + so->rx.state = ISOTP_IDLE; + + /* get the used sender LL_DL from the (first) CAN frame data length */ + so->rx.ll_dl = padlen(cf->len); + + /* the first frame has to use the entire frame up to LL_DL length */ + if (cf->len != so->rx.ll_dl) + return 1; + + /* get the FF_DL */ + so->rx.len = (cf->data[ae] & 0x0F) << 8; + so->rx.len += cf->data[ae + 1]; + + /* Check for FF_DL escape sequence supporting 32 bit PDU length */ + if (so->rx.len) { + ff_pci_sz = FF_PCI_SZ12; + } else { + /* FF_DL = 0 => get real length from next 4 bytes */ + so->rx.len = cf->data[ae + 2] << 24; + so->rx.len += cf->data[ae + 3] << 16; + so->rx.len += cf->data[ae + 4] << 8; + so->rx.len += cf->data[ae + 5]; + ff_pci_sz = FF_PCI_SZ32; + } + + /* take care of a potential SF_DL ESC offset for TX_DL > 8 */ + off = (so->rx.ll_dl > CAN_MAX_DLEN) ? 1 : 0; + + if (so->rx.len + ae + off + ff_pci_sz < so->rx.ll_dl) + return 1; + + /* PDU size > default => try max_pdu_size */ + if (so->rx.len > so->rx.buflen && so->rx.buflen < max_pdu_size) { + u8 *newbuf = kmalloc(max_pdu_size, GFP_ATOMIC); + + if (newbuf) { + so->rx.buf = newbuf; + so->rx.buflen = max_pdu_size; + } + } + + if (so->rx.len > so->rx.buflen) { + /* send FC frame with overflow status */ + isotp_send_fc(sk, ae, ISOTP_FC_OVFLW); + return 1; + } + + /* copy the first received data bytes */ + so->rx.idx = 0; + for (i = ae + ff_pci_sz; i < so->rx.ll_dl; i++) + so->rx.buf[so->rx.idx++] = cf->data[i]; + + /* initial setup for this pdu reception */ + so->rx.sn = 1; + so->rx.state = ISOTP_WAIT_DATA; + + /* no creation of flow control frames */ + if (so->opt.flags & CAN_ISOTP_LISTEN_MODE) + return 0; + + /* send our first FC frame */ + isotp_send_fc(sk, ae, ISOTP_FC_CTS); + return 0; +} + +static int isotp_rcv_cf(struct sock *sk, struct canfd_frame *cf, int ae, + struct sk_buff *skb) +{ + struct isotp_sock *so = isotp_sk(sk); + struct sk_buff *nskb; + int i; + + if (so->rx.state != ISOTP_WAIT_DATA) + return 0; + + /* drop if timestamp gap is less than force_rx_stmin nano secs */ + if (so->opt.flags & CAN_ISOTP_FORCE_RXSTMIN) { + if (ktime_to_ns(ktime_sub(skb->tstamp, so->lastrxcf_tstamp)) < + so->force_rx_stmin) + return 0; + + so->lastrxcf_tstamp = skb->tstamp; + } + + hrtimer_cancel(&so->rxtimer); + + /* CFs are never longer than the FF */ + if (cf->len > so->rx.ll_dl) + return 1; + + /* CFs have usually the LL_DL length */ + if (cf->len < so->rx.ll_dl) { + /* this is only allowed for the last CF */ + if (so->rx.len - so->rx.idx > so->rx.ll_dl - ae - N_PCI_SZ) + return 1; + } + + if ((cf->data[ae] & 0x0F) != so->rx.sn) { + /* wrong sn detected - report 'illegal byte sequence' */ + sk->sk_err = EILSEQ; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + + /* reset rx state */ + so->rx.state = ISOTP_IDLE; + return 1; + } + so->rx.sn++; + so->rx.sn %= 16; + + for (i = ae + N_PCI_SZ; i < cf->len; i++) { + so->rx.buf[so->rx.idx++] = cf->data[i]; + if (so->rx.idx >= so->rx.len) + break; + } + + if (so->rx.idx >= so->rx.len) { + /* we are done */ + so->rx.state = ISOTP_IDLE; + + if ((so->opt.flags & ISOTP_CHECK_PADDING) && + check_pad(so, cf, i + 1, so->opt.rxpad_content)) { + /* malformed PDU - report 'not a data message' */ + sk->sk_err = EBADMSG; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + return 1; + } + + nskb = alloc_skb(so->rx.len, gfp_any()); + if (!nskb) + return 1; + + memcpy(skb_put(nskb, so->rx.len), so->rx.buf, + so->rx.len); + + nskb->tstamp = skb->tstamp; + nskb->dev = skb->dev; + isotp_rcv_skb(nskb, sk); + return 0; + } + + /* perform blocksize handling, if enabled */ + if (!so->rxfc.bs || ++so->rx.bs < so->rxfc.bs) { + /* start rx timeout watchdog */ + hrtimer_start(&so->rxtimer, ktime_set(ISOTP_FC_TIMEOUT, 0), + HRTIMER_MODE_REL_SOFT); + return 0; + } + + /* no creation of flow control frames */ + if (so->opt.flags & CAN_ISOTP_LISTEN_MODE) + return 0; + + /* we reached the specified blocksize so->rxfc.bs */ + isotp_send_fc(sk, ae, ISOTP_FC_CTS); + return 0; +} + +static void isotp_rcv(struct sk_buff *skb, void *data) +{ + struct sock *sk = (struct sock *)data; + struct isotp_sock *so = isotp_sk(sk); + struct canfd_frame *cf; + int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0; + u8 n_pci_type, sf_dl; + + /* Strictly receive only frames with the configured MTU size + * => clear separation of CAN2.0 / CAN FD transport channels + */ + if (skb->len != so->ll.mtu) + return; + + cf = (struct canfd_frame *)skb->data; + + /* if enabled: check reception of my configured extended address */ + if (ae && cf->data[0] != so->opt.rx_ext_address) + return; + + n_pci_type = cf->data[ae] & 0xF0; + + /* Make sure the state changes and data structures stay consistent at + * CAN frame reception time. This locking is not needed in real world + * use cases but the inconsistency can be triggered with syzkaller. + */ + spin_lock(&so->rx_lock); + + if (so->opt.flags & CAN_ISOTP_HALF_DUPLEX) { + /* check rx/tx path half duplex expectations */ + if ((so->tx.state != ISOTP_IDLE && n_pci_type != N_PCI_FC) || + (so->rx.state != ISOTP_IDLE && n_pci_type == N_PCI_FC)) + goto out_unlock; + } + + switch (n_pci_type) { + case N_PCI_FC: + /* tx path: flow control frame containing the FC parameters */ + isotp_rcv_fc(so, cf, ae); + break; + + case N_PCI_SF: + /* rx path: single frame + * + * As we do not have a rx.ll_dl configuration, we can only test + * if the CAN frames payload length matches the LL_DL == 8 + * requirements - no matter if it's CAN 2.0 or CAN FD + */ + + /* get the SF_DL from the N_PCI byte */ + sf_dl = cf->data[ae] & 0x0F; + + if (cf->len <= CAN_MAX_DLEN) { + isotp_rcv_sf(sk, cf, SF_PCI_SZ4 + ae, skb, sf_dl); + } else { + if (can_is_canfd_skb(skb)) { + /* We have a CAN FD frame and CAN_DL is greater than 8: + * Only frames with the SF_DL == 0 ESC value are valid. + * + * If so take care of the increased SF PCI size + * (SF_PCI_SZ8) to point to the message content behind + * the extended SF PCI info and get the real SF_DL + * length value from the formerly first data byte. + */ + if (sf_dl == 0) + isotp_rcv_sf(sk, cf, SF_PCI_SZ8 + ae, skb, + cf->data[SF_PCI_SZ4 + ae]); + } + } + break; + + case N_PCI_FF: + /* rx path: first frame */ + isotp_rcv_ff(sk, cf, ae); + break; + + case N_PCI_CF: + /* rx path: consecutive frame */ + isotp_rcv_cf(sk, cf, ae, skb); + break; + } + +out_unlock: + spin_unlock(&so->rx_lock); +} + +static void isotp_fill_dataframe(struct canfd_frame *cf, struct isotp_sock *so, + int ae, int off) +{ + int pcilen = N_PCI_SZ + ae + off; + int space = so->tx.ll_dl - pcilen; + int num = min_t(int, so->tx.len - so->tx.idx, space); + int i; + + cf->can_id = so->txid; + cf->len = num + pcilen; + + if (num < space) { + if (so->opt.flags & CAN_ISOTP_TX_PADDING) { + /* user requested padding */ + cf->len = padlen(cf->len); + memset(cf->data, so->opt.txpad_content, cf->len); + } else if (cf->len > CAN_MAX_DLEN) { + /* mandatory padding for CAN FD frames */ + cf->len = padlen(cf->len); + memset(cf->data, CAN_ISOTP_DEFAULT_PAD_CONTENT, + cf->len); + } + } + + for (i = 0; i < num; i++) + cf->data[pcilen + i] = so->tx.buf[so->tx.idx++]; + + if (ae) + cf->data[0] = so->opt.ext_address; +} + +static void isotp_send_cframe(struct isotp_sock *so) +{ + struct sock *sk = &so->sk; + struct sk_buff *skb; + struct net_device *dev; + struct canfd_frame *cf; + int can_send_ret; + int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0; + + dev = dev_get_by_index(sock_net(sk), so->ifindex); + if (!dev) + return; + + skb = alloc_skb(so->ll.mtu + sizeof(struct can_skb_priv), GFP_ATOMIC); + if (!skb) { + dev_put(dev); + return; + } + + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + cf = (struct canfd_frame *)skb->data; + skb_put_zero(skb, so->ll.mtu); + + /* create consecutive frame */ + isotp_fill_dataframe(cf, so, ae, 0); + + /* place consecutive frame N_PCI in appropriate index */ + cf->data[ae] = N_PCI_CF | so->tx.sn++; + so->tx.sn %= 16; + so->tx.bs++; + + cf->flags = so->ll.tx_flags; + + skb->dev = dev; + can_skb_set_owner(skb, sk); + + /* cfecho should have been zero'ed by init/isotp_rcv_echo() */ + if (so->cfecho) + pr_notice_once("can-isotp: cfecho is %08X != 0\n", so->cfecho); + + /* set consecutive frame echo tag */ + so->cfecho = *(u32 *)cf->data; + + /* send frame with local echo enabled */ + can_send_ret = can_send(skb, 1); + if (can_send_ret) { + pr_notice_once("can-isotp: %s: can_send_ret %pe\n", + __func__, ERR_PTR(can_send_ret)); + if (can_send_ret == -ENOBUFS) + pr_notice_once("can-isotp: tx queue is full\n"); + } + dev_put(dev); +} + +static void isotp_create_fframe(struct canfd_frame *cf, struct isotp_sock *so, + int ae) +{ + int i; + int ff_pci_sz; + + cf->can_id = so->txid; + cf->len = so->tx.ll_dl; + if (ae) + cf->data[0] = so->opt.ext_address; + + /* create N_PCI bytes with 12/32 bit FF_DL data length */ + if (so->tx.len > MAX_12BIT_PDU_SIZE) { + /* use 32 bit FF_DL notation */ + cf->data[ae] = N_PCI_FF; + cf->data[ae + 1] = 0; + cf->data[ae + 2] = (u8)(so->tx.len >> 24) & 0xFFU; + cf->data[ae + 3] = (u8)(so->tx.len >> 16) & 0xFFU; + cf->data[ae + 4] = (u8)(so->tx.len >> 8) & 0xFFU; + cf->data[ae + 5] = (u8)so->tx.len & 0xFFU; + ff_pci_sz = FF_PCI_SZ32; + } else { + /* use 12 bit FF_DL notation */ + cf->data[ae] = (u8)(so->tx.len >> 8) | N_PCI_FF; + cf->data[ae + 1] = (u8)so->tx.len & 0xFFU; + ff_pci_sz = FF_PCI_SZ12; + } + + /* add first data bytes depending on ae */ + for (i = ae + ff_pci_sz; i < so->tx.ll_dl; i++) + cf->data[i] = so->tx.buf[so->tx.idx++]; + + so->tx.sn = 1; +} + +static void isotp_rcv_echo(struct sk_buff *skb, void *data) +{ + struct sock *sk = (struct sock *)data; + struct isotp_sock *so = isotp_sk(sk); + struct canfd_frame *cf = (struct canfd_frame *)skb->data; + + /* only handle my own local echo CF/SF skb's (no FF!) */ + if (skb->sk != sk || so->cfecho != *(u32 *)cf->data) + return; + + /* cancel local echo timeout */ + hrtimer_cancel(&so->txtimer); + + /* local echo skb with consecutive frame has been consumed */ + so->cfecho = 0; + + if (so->tx.idx >= so->tx.len) { + /* we are done */ + so->tx.state = ISOTP_IDLE; + wake_up_interruptible(&so->wait); + return; + } + + if (so->txfc.bs && so->tx.bs >= so->txfc.bs) { + /* stop and wait for FC with timeout */ + so->tx.state = ISOTP_WAIT_FC; + hrtimer_start(&so->txtimer, ktime_set(ISOTP_FC_TIMEOUT, 0), + HRTIMER_MODE_REL_SOFT); + return; + } + + /* no gap between data frames needed => use burst mode */ + if (!so->tx_gap) { + /* enable echo timeout handling */ + hrtimer_start(&so->txtimer, ktime_set(ISOTP_ECHO_TIMEOUT, 0), + HRTIMER_MODE_REL_SOFT); + isotp_send_cframe(so); + return; + } + + /* start timer to send next consecutive frame with correct delay */ + hrtimer_start(&so->txfrtimer, so->tx_gap, HRTIMER_MODE_REL_SOFT); +} + +static enum hrtimer_restart isotp_tx_timer_handler(struct hrtimer *hrtimer) +{ + struct isotp_sock *so = container_of(hrtimer, struct isotp_sock, + txtimer); + struct sock *sk = &so->sk; + + /* don't handle timeouts in IDLE or SHUTDOWN state */ + if (so->tx.state == ISOTP_IDLE || so->tx.state == ISOTP_SHUTDOWN) + return HRTIMER_NORESTART; + + /* we did not get any flow control or echo frame in time */ + + /* report 'communication error on send' */ + sk->sk_err = ECOMM; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + + /* reset tx state */ + so->tx.state = ISOTP_IDLE; + wake_up_interruptible(&so->wait); + + return HRTIMER_NORESTART; +} + +static enum hrtimer_restart isotp_txfr_timer_handler(struct hrtimer *hrtimer) +{ + struct isotp_sock *so = container_of(hrtimer, struct isotp_sock, + txfrtimer); + + /* start echo timeout handling and cover below protocol error */ + hrtimer_start(&so->txtimer, ktime_set(ISOTP_ECHO_TIMEOUT, 0), + HRTIMER_MODE_REL_SOFT); + + /* cfecho should be consumed by isotp_rcv_echo() here */ + if (so->tx.state == ISOTP_SENDING && !so->cfecho) + isotp_send_cframe(so); + + return HRTIMER_NORESTART; +} + +static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) +{ + struct sock *sk = sock->sk; + struct isotp_sock *so = isotp_sk(sk); + struct sk_buff *skb; + struct net_device *dev; + struct canfd_frame *cf; + int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0; + int wait_tx_done = (so->opt.flags & CAN_ISOTP_WAIT_TX_DONE) ? 1 : 0; + s64 hrtimer_sec = ISOTP_ECHO_TIMEOUT; + int off; + int err; + + if (!so->bound || so->tx.state == ISOTP_SHUTDOWN) + return -EADDRNOTAVAIL; + + while (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE) { + /* we do not support multiple buffers - for now */ + if (msg->msg_flags & MSG_DONTWAIT) + return -EAGAIN; + + if (so->tx.state == ISOTP_SHUTDOWN) + return -EADDRNOTAVAIL; + + /* wait for complete transmission of current pdu */ + err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE); + if (err) + goto err_event_drop; + } + + /* PDU size > default => try max_pdu_size */ + if (size > so->tx.buflen && so->tx.buflen < max_pdu_size) { + u8 *newbuf = kmalloc(max_pdu_size, GFP_KERNEL); + + if (newbuf) { + so->tx.buf = newbuf; + so->tx.buflen = max_pdu_size; + } + } + + if (!size || size > so->tx.buflen) { + err = -EINVAL; + goto err_out_drop; + } + + /* take care of a potential SF_DL ESC offset for TX_DL > 8 */ + off = (so->tx.ll_dl > CAN_MAX_DLEN) ? 1 : 0; + + /* does the given data fit into a single frame for SF_BROADCAST? */ + if ((isotp_bc_flags(so) == CAN_ISOTP_SF_BROADCAST) && + (size > so->tx.ll_dl - SF_PCI_SZ4 - ae - off)) { + err = -EINVAL; + goto err_out_drop; + } + + err = memcpy_from_msg(so->tx.buf, msg, size); + if (err < 0) + goto err_out_drop; + + dev = dev_get_by_index(sock_net(sk), so->ifindex); + if (!dev) { + err = -ENXIO; + goto err_out_drop; + } + + skb = sock_alloc_send_skb(sk, so->ll.mtu + sizeof(struct can_skb_priv), + msg->msg_flags & MSG_DONTWAIT, &err); + if (!skb) { + dev_put(dev); + goto err_out_drop; + } + + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + so->tx.len = size; + so->tx.idx = 0; + + cf = (struct canfd_frame *)skb->data; + skb_put_zero(skb, so->ll.mtu); + + /* cfecho should have been zero'ed by init / former isotp_rcv_echo() */ + if (so->cfecho) + pr_notice_once("can-isotp: uninit cfecho %08X\n", so->cfecho); + + /* check for single frame transmission depending on TX_DL */ + if (size <= so->tx.ll_dl - SF_PCI_SZ4 - ae - off) { + /* The message size generally fits into a SingleFrame - good. + * + * SF_DL ESC offset optimization: + * + * When TX_DL is greater 8 but the message would still fit + * into a 8 byte CAN frame, we can omit the offset. + * This prevents a protocol caused length extension from + * CAN_DL = 8 to CAN_DL = 12 due to the SF_SL ESC handling. + */ + if (size <= CAN_MAX_DLEN - SF_PCI_SZ4 - ae) + off = 0; + + isotp_fill_dataframe(cf, so, ae, off); + + /* place single frame N_PCI w/o length in appropriate index */ + cf->data[ae] = N_PCI_SF; + + /* place SF_DL size value depending on the SF_DL ESC offset */ + if (off) + cf->data[SF_PCI_SZ4 + ae] = size; + else + cf->data[ae] |= size; + + /* set CF echo tag for isotp_rcv_echo() (SF-mode) */ + so->cfecho = *(u32 *)cf->data; + } else { + /* send first frame */ + + isotp_create_fframe(cf, so, ae); + + if (isotp_bc_flags(so) == CAN_ISOTP_CF_BROADCAST) { + /* set timer for FC-less operation (STmin = 0) */ + if (so->opt.flags & CAN_ISOTP_FORCE_TXSTMIN) + so->tx_gap = ktime_set(0, so->force_tx_stmin); + else + so->tx_gap = ktime_set(0, so->frame_txtime); + + /* disable wait for FCs due to activated block size */ + so->txfc.bs = 0; + + /* set CF echo tag for isotp_rcv_echo() (CF-mode) */ + so->cfecho = *(u32 *)cf->data; + } else { + /* standard flow control check */ + so->tx.state = ISOTP_WAIT_FIRST_FC; + + /* start timeout for FC */ + hrtimer_sec = ISOTP_FC_TIMEOUT; + + /* no CF echo tag for isotp_rcv_echo() (FF-mode) */ + so->cfecho = 0; + } + } + + hrtimer_start(&so->txtimer, ktime_set(hrtimer_sec, 0), + HRTIMER_MODE_REL_SOFT); + + /* send the first or only CAN frame */ + cf->flags = so->ll.tx_flags; + + skb->dev = dev; + skb->sk = sk; + err = can_send(skb, 1); + dev_put(dev); + if (err) { + pr_notice_once("can-isotp: %s: can_send_ret %pe\n", + __func__, ERR_PTR(err)); + + /* no transmission -> no timeout monitoring */ + hrtimer_cancel(&so->txtimer); + + /* reset consecutive frame echo tag */ + so->cfecho = 0; + + goto err_out_drop; + } + + if (wait_tx_done) { + /* wait for complete transmission of current pdu */ + err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE); + if (err) + goto err_event_drop; + + err = sock_error(sk); + if (err) + return err; + } + + return size; + +err_event_drop: + /* got signal: force tx state machine to be idle */ + so->tx.state = ISOTP_IDLE; + hrtimer_cancel(&so->txfrtimer); + hrtimer_cancel(&so->txtimer); +err_out_drop: + /* drop this PDU and unlock a potential wait queue */ + so->tx.state = ISOTP_IDLE; + wake_up_interruptible(&so->wait); + + return err; +} + +static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags) +{ + struct sock *sk = sock->sk; + struct sk_buff *skb; + struct isotp_sock *so = isotp_sk(sk); + int ret = 0; + + if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK | MSG_CMSG_COMPAT)) + return -EINVAL; + + if (!so->bound) + return -EADDRNOTAVAIL; + + skb = skb_recv_datagram(sk, flags, &ret); + if (!skb) + return ret; + + if (size < skb->len) + msg->msg_flags |= MSG_TRUNC; + else + size = skb->len; + + ret = memcpy_to_msg(msg, skb->data, size); + if (ret < 0) + goto out_err; + + sock_recv_cmsgs(msg, sk, skb); + + if (msg->msg_name) { + __sockaddr_check_size(ISOTP_MIN_NAMELEN); + msg->msg_namelen = ISOTP_MIN_NAMELEN; + memcpy(msg->msg_name, skb->cb, msg->msg_namelen); + } + + /* set length of return value */ + ret = (flags & MSG_TRUNC) ? skb->len : size; + +out_err: + skb_free_datagram(sk, skb); + + return ret; +} + +static int isotp_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct isotp_sock *so; + struct net *net; + + if (!sk) + return 0; + + so = isotp_sk(sk); + net = sock_net(sk); + + /* wait for complete transmission of current pdu */ + while (wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE) == 0 && + cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SHUTDOWN) != ISOTP_IDLE) + ; + + /* force state machines to be idle also when a signal occurred */ + so->tx.state = ISOTP_SHUTDOWN; + so->rx.state = ISOTP_IDLE; + + spin_lock(&isotp_notifier_lock); + while (isotp_busy_notifier == so) { + spin_unlock(&isotp_notifier_lock); + schedule_timeout_uninterruptible(1); + spin_lock(&isotp_notifier_lock); + } + list_del(&so->notifier); + spin_unlock(&isotp_notifier_lock); + + lock_sock(sk); + + /* remove current filters & unregister */ + if (so->bound) { + if (so->ifindex) { + struct net_device *dev; + + dev = dev_get_by_index(net, so->ifindex); + if (dev) { + if (isotp_register_rxid(so)) + can_rx_unregister(net, dev, so->rxid, + SINGLE_MASK(so->rxid), + isotp_rcv, sk); + + can_rx_unregister(net, dev, so->txid, + SINGLE_MASK(so->txid), + isotp_rcv_echo, sk); + dev_put(dev); + synchronize_rcu(); + } + } + } + + hrtimer_cancel(&so->txfrtimer); + hrtimer_cancel(&so->txtimer); + hrtimer_cancel(&so->rxtimer); + + so->ifindex = 0; + so->bound = 0; + + if (so->rx.buf != so->rx.sbuf) + kfree(so->rx.buf); + + if (so->tx.buf != so->tx.sbuf) + kfree(so->tx.buf); + + sock_orphan(sk); + sock->sk = NULL; + + release_sock(sk); + sock_put(sk); + + return 0; +} + +static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct sock *sk = sock->sk; + struct isotp_sock *so = isotp_sk(sk); + struct net *net = sock_net(sk); + int ifindex; + struct net_device *dev; + canid_t tx_id = addr->can_addr.tp.tx_id; + canid_t rx_id = addr->can_addr.tp.rx_id; + int err = 0; + int notify_enetdown = 0; + + if (len < ISOTP_MIN_NAMELEN) + return -EINVAL; + + if (addr->can_family != AF_CAN) + return -EINVAL; + + /* sanitize tx CAN identifier */ + if (tx_id & CAN_EFF_FLAG) + tx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK); + else + tx_id &= CAN_SFF_MASK; + + /* give feedback on wrong CAN-ID value */ + if (tx_id != addr->can_addr.tp.tx_id) + return -EINVAL; + + /* sanitize rx CAN identifier (if needed) */ + if (isotp_register_rxid(so)) { + if (rx_id & CAN_EFF_FLAG) + rx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK); + else + rx_id &= CAN_SFF_MASK; + + /* give feedback on wrong CAN-ID value */ + if (rx_id != addr->can_addr.tp.rx_id) + return -EINVAL; + } + + if (!addr->can_ifindex) + return -ENODEV; + + lock_sock(sk); + + if (so->bound) { + err = -EINVAL; + goto out; + } + + /* ensure different CAN IDs when the rx_id is to be registered */ + if (isotp_register_rxid(so) && rx_id == tx_id) { + err = -EADDRNOTAVAIL; + goto out; + } + + dev = dev_get_by_index(net, addr->can_ifindex); + if (!dev) { + err = -ENODEV; + goto out; + } + if (dev->type != ARPHRD_CAN) { + dev_put(dev); + err = -ENODEV; + goto out; + } + if (dev->mtu < so->ll.mtu) { + dev_put(dev); + err = -EINVAL; + goto out; + } + if (!(dev->flags & IFF_UP)) + notify_enetdown = 1; + + ifindex = dev->ifindex; + + if (isotp_register_rxid(so)) + can_rx_register(net, dev, rx_id, SINGLE_MASK(rx_id), + isotp_rcv, sk, "isotp", sk); + + /* no consecutive frame echo skb in flight */ + so->cfecho = 0; + + /* register for echo skb's */ + can_rx_register(net, dev, tx_id, SINGLE_MASK(tx_id), + isotp_rcv_echo, sk, "isotpe", sk); + + dev_put(dev); + + /* switch to new settings */ + so->ifindex = ifindex; + so->rxid = rx_id; + so->txid = tx_id; + so->bound = 1; + +out: + release_sock(sk); + + if (notify_enetdown) { + sk->sk_err = ENETDOWN; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + } + + return err; +} + +static int isotp_getname(struct socket *sock, struct sockaddr *uaddr, int peer) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct sock *sk = sock->sk; + struct isotp_sock *so = isotp_sk(sk); + + if (peer) + return -EOPNOTSUPP; + + memset(addr, 0, ISOTP_MIN_NAMELEN); + addr->can_family = AF_CAN; + addr->can_ifindex = so->ifindex; + addr->can_addr.tp.rx_id = so->rxid; + addr->can_addr.tp.tx_id = so->txid; + + return ISOTP_MIN_NAMELEN; +} + +static int isotp_setsockopt_locked(struct socket *sock, int level, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct sock *sk = sock->sk; + struct isotp_sock *so = isotp_sk(sk); + int ret = 0; + + if (so->bound) + return -EISCONN; + + switch (optname) { + case CAN_ISOTP_OPTS: + if (optlen != sizeof(struct can_isotp_options)) + return -EINVAL; + + if (copy_from_sockptr(&so->opt, optval, optlen)) + return -EFAULT; + + /* no separate rx_ext_address is given => use ext_address */ + if (!(so->opt.flags & CAN_ISOTP_RX_EXT_ADDR)) + so->opt.rx_ext_address = so->opt.ext_address; + + /* these broadcast flags are not allowed together */ + if (isotp_bc_flags(so) == ISOTP_ALL_BC_FLAGS) { + /* CAN_ISOTP_SF_BROADCAST is prioritized */ + so->opt.flags &= ~CAN_ISOTP_CF_BROADCAST; + + /* give user feedback on wrong config attempt */ + ret = -EINVAL; + } + + /* check for frame_txtime changes (0 => no changes) */ + if (so->opt.frame_txtime) { + if (so->opt.frame_txtime == CAN_ISOTP_FRAME_TXTIME_ZERO) + so->frame_txtime = 0; + else + so->frame_txtime = so->opt.frame_txtime; + } + break; + + case CAN_ISOTP_RECV_FC: + if (optlen != sizeof(struct can_isotp_fc_options)) + return -EINVAL; + + if (copy_from_sockptr(&so->rxfc, optval, optlen)) + return -EFAULT; + break; + + case CAN_ISOTP_TX_STMIN: + if (optlen != sizeof(u32)) + return -EINVAL; + + if (copy_from_sockptr(&so->force_tx_stmin, optval, optlen)) + return -EFAULT; + break; + + case CAN_ISOTP_RX_STMIN: + if (optlen != sizeof(u32)) + return -EINVAL; + + if (copy_from_sockptr(&so->force_rx_stmin, optval, optlen)) + return -EFAULT; + break; + + case CAN_ISOTP_LL_OPTS: + if (optlen == sizeof(struct can_isotp_ll_options)) { + struct can_isotp_ll_options ll; + + if (copy_from_sockptr(&ll, optval, optlen)) + return -EFAULT; + + /* check for correct ISO 11898-1 DLC data length */ + if (ll.tx_dl != padlen(ll.tx_dl)) + return -EINVAL; + + if (ll.mtu != CAN_MTU && ll.mtu != CANFD_MTU) + return -EINVAL; + + if (ll.mtu == CAN_MTU && + (ll.tx_dl > CAN_MAX_DLEN || ll.tx_flags != 0)) + return -EINVAL; + + memcpy(&so->ll, &ll, sizeof(ll)); + + /* set ll_dl for tx path to similar place as for rx */ + so->tx.ll_dl = ll.tx_dl; + } else { + return -EINVAL; + } + break; + + default: + ret = -ENOPROTOOPT; + } + + return ret; +} + +static int isotp_setsockopt(struct socket *sock, int level, int optname, + sockptr_t optval, unsigned int optlen) + +{ + struct sock *sk = sock->sk; + int ret; + + if (level != SOL_CAN_ISOTP) + return -EINVAL; + + lock_sock(sk); + ret = isotp_setsockopt_locked(sock, level, optname, optval, optlen); + release_sock(sk); + return ret; +} + +static int isotp_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = sock->sk; + struct isotp_sock *so = isotp_sk(sk); + int len; + void *val; + + if (level != SOL_CAN_ISOTP) + return -EINVAL; + if (get_user(len, optlen)) + return -EFAULT; + if (len < 0) + return -EINVAL; + + switch (optname) { + case CAN_ISOTP_OPTS: + len = min_t(int, len, sizeof(struct can_isotp_options)); + val = &so->opt; + break; + + case CAN_ISOTP_RECV_FC: + len = min_t(int, len, sizeof(struct can_isotp_fc_options)); + val = &so->rxfc; + break; + + case CAN_ISOTP_TX_STMIN: + len = min_t(int, len, sizeof(u32)); + val = &so->force_tx_stmin; + break; + + case CAN_ISOTP_RX_STMIN: + len = min_t(int, len, sizeof(u32)); + val = &so->force_rx_stmin; + break; + + case CAN_ISOTP_LL_OPTS: + len = min_t(int, len, sizeof(struct can_isotp_ll_options)); + val = &so->ll; + break; + + default: + return -ENOPROTOOPT; + } + + if (put_user(len, optlen)) + return -EFAULT; + if (copy_to_user(optval, val, len)) + return -EFAULT; + return 0; +} + +static void isotp_notify(struct isotp_sock *so, unsigned long msg, + struct net_device *dev) +{ + struct sock *sk = &so->sk; + + if (!net_eq(dev_net(dev), sock_net(sk))) + return; + + if (so->ifindex != dev->ifindex) + return; + + switch (msg) { + case NETDEV_UNREGISTER: + lock_sock(sk); + /* remove current filters & unregister */ + if (so->bound) { + if (isotp_register_rxid(so)) + can_rx_unregister(dev_net(dev), dev, so->rxid, + SINGLE_MASK(so->rxid), + isotp_rcv, sk); + + can_rx_unregister(dev_net(dev), dev, so->txid, + SINGLE_MASK(so->txid), + isotp_rcv_echo, sk); + } + + so->ifindex = 0; + so->bound = 0; + release_sock(sk); + + sk->sk_err = ENODEV; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + break; + + case NETDEV_DOWN: + sk->sk_err = ENETDOWN; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + break; + } +} + +static int isotp_notifier(struct notifier_block *nb, unsigned long msg, + void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + + if (dev->type != ARPHRD_CAN) + return NOTIFY_DONE; + if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN) + return NOTIFY_DONE; + if (unlikely(isotp_busy_notifier)) /* Check for reentrant bug. */ + return NOTIFY_DONE; + + spin_lock(&isotp_notifier_lock); + list_for_each_entry(isotp_busy_notifier, &isotp_notifier_list, notifier) { + spin_unlock(&isotp_notifier_lock); + isotp_notify(isotp_busy_notifier, msg, dev); + spin_lock(&isotp_notifier_lock); + } + isotp_busy_notifier = NULL; + spin_unlock(&isotp_notifier_lock); + return NOTIFY_DONE; +} + +static int isotp_init(struct sock *sk) +{ + struct isotp_sock *so = isotp_sk(sk); + + so->ifindex = 0; + so->bound = 0; + + so->opt.flags = CAN_ISOTP_DEFAULT_FLAGS; + so->opt.ext_address = CAN_ISOTP_DEFAULT_EXT_ADDRESS; + so->opt.rx_ext_address = CAN_ISOTP_DEFAULT_EXT_ADDRESS; + so->opt.rxpad_content = CAN_ISOTP_DEFAULT_PAD_CONTENT; + so->opt.txpad_content = CAN_ISOTP_DEFAULT_PAD_CONTENT; + so->opt.frame_txtime = CAN_ISOTP_DEFAULT_FRAME_TXTIME; + so->frame_txtime = CAN_ISOTP_DEFAULT_FRAME_TXTIME; + so->rxfc.bs = CAN_ISOTP_DEFAULT_RECV_BS; + so->rxfc.stmin = CAN_ISOTP_DEFAULT_RECV_STMIN; + so->rxfc.wftmax = CAN_ISOTP_DEFAULT_RECV_WFTMAX; + so->ll.mtu = CAN_ISOTP_DEFAULT_LL_MTU; + so->ll.tx_dl = CAN_ISOTP_DEFAULT_LL_TX_DL; + so->ll.tx_flags = CAN_ISOTP_DEFAULT_LL_TX_FLAGS; + + /* set ll_dl for tx path to similar place as for rx */ + so->tx.ll_dl = so->ll.tx_dl; + + so->rx.state = ISOTP_IDLE; + so->tx.state = ISOTP_IDLE; + + so->rx.buf = so->rx.sbuf; + so->tx.buf = so->tx.sbuf; + so->rx.buflen = ARRAY_SIZE(so->rx.sbuf); + so->tx.buflen = ARRAY_SIZE(so->tx.sbuf); + + hrtimer_init(&so->rxtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); + so->rxtimer.function = isotp_rx_timer_handler; + hrtimer_init(&so->txtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); + so->txtimer.function = isotp_tx_timer_handler; + hrtimer_init(&so->txfrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); + so->txfrtimer.function = isotp_txfr_timer_handler; + + init_waitqueue_head(&so->wait); + spin_lock_init(&so->rx_lock); + + spin_lock(&isotp_notifier_lock); + list_add_tail(&so->notifier, &isotp_notifier_list); + spin_unlock(&isotp_notifier_lock); + + return 0; +} + +static __poll_t isotp_poll(struct file *file, struct socket *sock, poll_table *wait) +{ + struct sock *sk = sock->sk; + struct isotp_sock *so = isotp_sk(sk); + + __poll_t mask = datagram_poll(file, sock, wait); + poll_wait(file, &so->wait, wait); + + /* Check for false positives due to TX state */ + if ((mask & EPOLLWRNORM) && (so->tx.state != ISOTP_IDLE)) + mask &= ~(EPOLLOUT | EPOLLWRNORM); + + return mask; +} + +static int isotp_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + /* no ioctls for socket layer -> hand it down to NIC layer */ + return -ENOIOCTLCMD; +} + +static const struct proto_ops isotp_ops = { + .family = PF_CAN, + .release = isotp_release, + .bind = isotp_bind, + .connect = sock_no_connect, + .socketpair = sock_no_socketpair, + .accept = sock_no_accept, + .getname = isotp_getname, + .poll = isotp_poll, + .ioctl = isotp_sock_no_ioctlcmd, + .gettstamp = sock_gettstamp, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .setsockopt = isotp_setsockopt, + .getsockopt = isotp_getsockopt, + .sendmsg = isotp_sendmsg, + .recvmsg = isotp_recvmsg, + .mmap = sock_no_mmap, +}; + +static struct proto isotp_proto __read_mostly = { + .name = "CAN_ISOTP", + .owner = THIS_MODULE, + .obj_size = sizeof(struct isotp_sock), + .init = isotp_init, +}; + +static const struct can_proto isotp_can_proto = { + .type = SOCK_DGRAM, + .protocol = CAN_ISOTP, + .ops = &isotp_ops, + .prot = &isotp_proto, +}; + +static struct notifier_block canisotp_notifier = { + .notifier_call = isotp_notifier +}; + +static __init int isotp_module_init(void) +{ + int err; + + max_pdu_size = max_t(unsigned int, max_pdu_size, MAX_12BIT_PDU_SIZE); + max_pdu_size = min_t(unsigned int, max_pdu_size, MAX_PDU_SIZE); + + pr_info("can: isotp protocol (max_pdu_size %d)\n", max_pdu_size); + + err = can_proto_register(&isotp_can_proto); + if (err < 0) + pr_err("can: registration of isotp protocol failed %pe\n", ERR_PTR(err)); + else + register_netdevice_notifier(&canisotp_notifier); + + return err; +} + +static __exit void isotp_module_exit(void) +{ + can_proto_unregister(&isotp_can_proto); + unregister_netdevice_notifier(&canisotp_notifier); +} + +module_init(isotp_module_init); +module_exit(isotp_module_exit); diff --git a/net/can/j1939/Kconfig b/net/can/j1939/Kconfig new file mode 100644 index 000000000..2998298b7 --- /dev/null +++ b/net/can/j1939/Kconfig @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# SAE J1939 network layer core configuration +# + +config CAN_J1939 + tristate "SAE J1939" + depends on CAN + help + SAE J1939 + Say Y to have in-kernel support for j1939 socket type. This + allows communication according to SAE j1939. + The relevant parts in kernel are + SAE j1939-21 (datalink & transport protocol) + & SAE j1939-81 (network management). diff --git a/net/can/j1939/Makefile b/net/can/j1939/Makefile new file mode 100644 index 000000000..19181bdae --- /dev/null +++ b/net/can/j1939/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_CAN_J1939) += can-j1939.o + +can-j1939-objs := \ + address-claim.o \ + bus.o \ + main.o \ + socket.o \ + transport.o diff --git a/net/can/j1939/address-claim.c b/net/can/j1939/address-claim.c new file mode 100644 index 000000000..ca4ad6cdd --- /dev/null +++ b/net/can/j1939/address-claim.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2010-2011 EIA Electronics, +// Pieter Beyens <pieter.beyens@eia.be> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +/* J1939 Address Claiming. + * Address Claiming in the kernel + * - keeps track of the AC states of ECU's, + * - resolves NAME<=>SA taking into account the AC states of ECU's. + * + * All Address Claim msgs (including host-originated msg) are processed + * at the receive path (a sent msg is always received again via CAN echo). + * As such, the processing of AC msgs is done in the order on which msgs + * are sent on the bus. + * + * This module doesn't send msgs itself (e.g. replies on Address Claims), + * this is the responsibility of a user space application or daemon. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/netdevice.h> +#include <linux/skbuff.h> + +#include "j1939-priv.h" + +static inline name_t j1939_skb_to_name(const struct sk_buff *skb) +{ + return le64_to_cpup((__le64 *)skb->data); +} + +static inline bool j1939_ac_msg_is_request(struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + int req_pgn; + + if (skb->len < 3 || skcb->addr.pgn != J1939_PGN_REQUEST) + return false; + + req_pgn = skb->data[0] | (skb->data[1] << 8) | (skb->data[2] << 16); + + return req_pgn == J1939_PGN_ADDRESS_CLAIMED; +} + +static int j1939_ac_verify_outgoing(struct j1939_priv *priv, + struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + + if (skb->len != 8) { + netdev_notice(priv->ndev, "tx address claim with dlc %i\n", + skb->len); + return -EPROTO; + } + + if (skcb->addr.src_name != j1939_skb_to_name(skb)) { + netdev_notice(priv->ndev, "tx address claim with different name\n"); + return -EPROTO; + } + + if (skcb->addr.sa == J1939_NO_ADDR) { + netdev_notice(priv->ndev, "tx address claim with broadcast sa\n"); + return -EPROTO; + } + + /* ac must always be a broadcast */ + if (skcb->addr.dst_name || skcb->addr.da != J1939_NO_ADDR) { + netdev_notice(priv->ndev, "tx address claim with dest, not broadcast\n"); + return -EPROTO; + } + return 0; +} + +int j1939_ac_fixup(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + int ret; + u8 addr; + + /* network mgmt: address claiming msgs */ + if (skcb->addr.pgn == J1939_PGN_ADDRESS_CLAIMED) { + struct j1939_ecu *ecu; + + ret = j1939_ac_verify_outgoing(priv, skb); + /* return both when failure & when successful */ + if (ret < 0) + return ret; + ecu = j1939_ecu_get_by_name(priv, skcb->addr.src_name); + if (!ecu) + return -ENODEV; + + if (ecu->addr != skcb->addr.sa) + /* hold further traffic for ecu, remove from parent */ + j1939_ecu_unmap(ecu); + j1939_ecu_put(ecu); + } else if (skcb->addr.src_name) { + /* assign source address */ + addr = j1939_name_to_addr(priv, skcb->addr.src_name); + if (!j1939_address_is_unicast(addr) && + !j1939_ac_msg_is_request(skb)) { + netdev_notice(priv->ndev, "tx drop: invalid sa for name 0x%016llx\n", + skcb->addr.src_name); + return -EADDRNOTAVAIL; + } + skcb->addr.sa = addr; + } + + /* assign destination address */ + if (skcb->addr.dst_name) { + addr = j1939_name_to_addr(priv, skcb->addr.dst_name); + if (!j1939_address_is_unicast(addr)) { + netdev_notice(priv->ndev, "tx drop: invalid da for name 0x%016llx\n", + skcb->addr.dst_name); + return -EADDRNOTAVAIL; + } + skcb->addr.da = addr; + } + return 0; +} + +static void j1939_ac_process(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_ecu *ecu, *prev; + name_t name; + + if (skb->len != 8) { + netdev_notice(priv->ndev, "rx address claim with wrong dlc %i\n", + skb->len); + return; + } + + name = j1939_skb_to_name(skb); + skcb->addr.src_name = name; + if (!name) { + netdev_notice(priv->ndev, "rx address claim without name\n"); + return; + } + + if (!j1939_address_is_valid(skcb->addr.sa)) { + netdev_notice(priv->ndev, "rx address claim with broadcast sa\n"); + return; + } + + write_lock_bh(&priv->lock); + + /* Few words on the ECU ref counting: + * + * First we get an ECU handle, either with + * j1939_ecu_get_by_name_locked() (increments the ref counter) + * or j1939_ecu_create_locked() (initializes an ECU object + * with a ref counter of 1). + * + * j1939_ecu_unmap_locked() will decrement the ref counter, + * but only if the ECU was mapped before. So "ecu" still + * belongs to us. + * + * j1939_ecu_timer_start() will increment the ref counter + * before it starts the timer, so we can put the ecu when + * leaving this function. + */ + ecu = j1939_ecu_get_by_name_locked(priv, name); + + if (ecu && ecu->addr == skcb->addr.sa) { + /* The ISO 11783-5 standard, in "4.5.2 - Address claim + * requirements", states: + * d) No CF shall begin, or resume, transmission on the + * network until 250 ms after it has successfully claimed + * an address except when responding to a request for + * address-claimed. + * + * But "Figure 6" and "Figure 7" in "4.5.4.2 - Address-claim + * prioritization" show that the CF begins the transmission + * after 250 ms from the first AC (address-claimed) message + * even if it sends another AC message during that time window + * to resolve the address contention with another CF. + * + * As stated in "4.4.2.3 - Address-claimed message": + * In order to successfully claim an address, the CF sending + * an address claimed message shall not receive a contending + * claim from another CF for at least 250 ms. + * + * As stated in "4.4.3.2 - NAME management (NM) message": + * 1) A commanding CF can + * d) request that a CF with a specified NAME transmit + * the address-claimed message with its current NAME. + * 2) A target CF shall + * d) send an address-claimed message in response to a + * request for a matching NAME + * + * Taking the above arguments into account, the 250 ms wait is + * requested only during network initialization. + * + * Do not restart the timer on AC message if both the NAME and + * the address match and so if the address has already been + * claimed (timer has expired) or the AC message has been sent + * to resolve the contention with another CF (timer is still + * running). + */ + goto out_ecu_put; + } + + if (!ecu && j1939_address_is_unicast(skcb->addr.sa)) + ecu = j1939_ecu_create_locked(priv, name); + + if (IS_ERR_OR_NULL(ecu)) + goto out_unlock_bh; + + /* cancel pending (previous) address claim */ + j1939_ecu_timer_cancel(ecu); + + if (j1939_address_is_idle(skcb->addr.sa)) { + j1939_ecu_unmap_locked(ecu); + goto out_ecu_put; + } + + /* save new addr */ + if (ecu->addr != skcb->addr.sa) + j1939_ecu_unmap_locked(ecu); + ecu->addr = skcb->addr.sa; + + prev = j1939_ecu_get_by_addr_locked(priv, skcb->addr.sa); + if (prev) { + if (ecu->name > prev->name) { + j1939_ecu_unmap_locked(ecu); + j1939_ecu_put(prev); + goto out_ecu_put; + } else { + /* kick prev if less or equal */ + j1939_ecu_unmap_locked(prev); + j1939_ecu_put(prev); + } + } + + j1939_ecu_timer_start(ecu); + out_ecu_put: + j1939_ecu_put(ecu); + out_unlock_bh: + write_unlock_bh(&priv->lock); +} + +void j1939_ac_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_ecu *ecu; + + /* network mgmt */ + if (skcb->addr.pgn == J1939_PGN_ADDRESS_CLAIMED) { + j1939_ac_process(priv, skb); + } else if (j1939_address_is_unicast(skcb->addr.sa)) { + /* assign source name */ + ecu = j1939_ecu_get_by_addr(priv, skcb->addr.sa); + if (ecu) { + skcb->addr.src_name = ecu->name; + j1939_ecu_put(ecu); + } + } + + /* assign destination name */ + ecu = j1939_ecu_get_by_addr(priv, skcb->addr.da); + if (ecu) { + skcb->addr.dst_name = ecu->name; + j1939_ecu_put(ecu); + } +} diff --git a/net/can/j1939/bus.c b/net/can/j1939/bus.c new file mode 100644 index 000000000..486687901 --- /dev/null +++ b/net/can/j1939/bus.c @@ -0,0 +1,333 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +/* bus for j1939 remote devices + * Since rtnetlink, no real bus is used. + */ + +#include <net/sock.h> + +#include "j1939-priv.h" + +static void __j1939_ecu_release(struct kref *kref) +{ + struct j1939_ecu *ecu = container_of(kref, struct j1939_ecu, kref); + struct j1939_priv *priv = ecu->priv; + + list_del(&ecu->list); + kfree(ecu); + j1939_priv_put(priv); +} + +void j1939_ecu_put(struct j1939_ecu *ecu) +{ + kref_put(&ecu->kref, __j1939_ecu_release); +} + +static void j1939_ecu_get(struct j1939_ecu *ecu) +{ + kref_get(&ecu->kref); +} + +static bool j1939_ecu_is_mapped_locked(struct j1939_ecu *ecu) +{ + struct j1939_priv *priv = ecu->priv; + + lockdep_assert_held(&priv->lock); + + return j1939_ecu_find_by_addr_locked(priv, ecu->addr) == ecu; +} + +/* ECU device interface */ +/* map ECU to a bus address space */ +static void j1939_ecu_map_locked(struct j1939_ecu *ecu) +{ + struct j1939_priv *priv = ecu->priv; + struct j1939_addr_ent *ent; + + lockdep_assert_held(&priv->lock); + + if (!j1939_address_is_unicast(ecu->addr)) + return; + + ent = &priv->ents[ecu->addr]; + + if (ent->ecu) { + netdev_warn(priv->ndev, "Trying to map already mapped ECU, addr: 0x%02x, name: 0x%016llx. Skip it.\n", + ecu->addr, ecu->name); + return; + } + + j1939_ecu_get(ecu); + ent->ecu = ecu; + ent->nusers += ecu->nusers; +} + +/* unmap ECU from a bus address space */ +void j1939_ecu_unmap_locked(struct j1939_ecu *ecu) +{ + struct j1939_priv *priv = ecu->priv; + struct j1939_addr_ent *ent; + + lockdep_assert_held(&priv->lock); + + if (!j1939_address_is_unicast(ecu->addr)) + return; + + if (!j1939_ecu_is_mapped_locked(ecu)) + return; + + ent = &priv->ents[ecu->addr]; + ent->ecu = NULL; + ent->nusers -= ecu->nusers; + j1939_ecu_put(ecu); +} + +void j1939_ecu_unmap(struct j1939_ecu *ecu) +{ + write_lock_bh(&ecu->priv->lock); + j1939_ecu_unmap_locked(ecu); + write_unlock_bh(&ecu->priv->lock); +} + +void j1939_ecu_unmap_all(struct j1939_priv *priv) +{ + int i; + + write_lock_bh(&priv->lock); + for (i = 0; i < ARRAY_SIZE(priv->ents); i++) + if (priv->ents[i].ecu) + j1939_ecu_unmap_locked(priv->ents[i].ecu); + write_unlock_bh(&priv->lock); +} + +void j1939_ecu_timer_start(struct j1939_ecu *ecu) +{ + /* The ECU is held here and released in the + * j1939_ecu_timer_handler() or j1939_ecu_timer_cancel(). + */ + j1939_ecu_get(ecu); + + /* Schedule timer in 250 msec to commit address change. */ + hrtimer_start(&ecu->ac_timer, ms_to_ktime(250), + HRTIMER_MODE_REL_SOFT); +} + +void j1939_ecu_timer_cancel(struct j1939_ecu *ecu) +{ + if (hrtimer_cancel(&ecu->ac_timer)) + j1939_ecu_put(ecu); +} + +static enum hrtimer_restart j1939_ecu_timer_handler(struct hrtimer *hrtimer) +{ + struct j1939_ecu *ecu = + container_of(hrtimer, struct j1939_ecu, ac_timer); + struct j1939_priv *priv = ecu->priv; + + write_lock_bh(&priv->lock); + /* TODO: can we test if ecu->addr is unicast before starting + * the timer? + */ + j1939_ecu_map_locked(ecu); + + /* The corresponding j1939_ecu_get() is in + * j1939_ecu_timer_start(). + */ + j1939_ecu_put(ecu); + write_unlock_bh(&priv->lock); + + return HRTIMER_NORESTART; +} + +struct j1939_ecu *j1939_ecu_create_locked(struct j1939_priv *priv, name_t name) +{ + struct j1939_ecu *ecu; + + lockdep_assert_held(&priv->lock); + + ecu = kzalloc(sizeof(*ecu), gfp_any()); + if (!ecu) + return ERR_PTR(-ENOMEM); + kref_init(&ecu->kref); + ecu->addr = J1939_IDLE_ADDR; + ecu->name = name; + + hrtimer_init(&ecu->ac_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); + ecu->ac_timer.function = j1939_ecu_timer_handler; + INIT_LIST_HEAD(&ecu->list); + + j1939_priv_get(priv); + ecu->priv = priv; + list_add_tail(&ecu->list, &priv->ecus); + + return ecu; +} + +struct j1939_ecu *j1939_ecu_find_by_addr_locked(struct j1939_priv *priv, + u8 addr) +{ + lockdep_assert_held(&priv->lock); + + return priv->ents[addr].ecu; +} + +struct j1939_ecu *j1939_ecu_get_by_addr_locked(struct j1939_priv *priv, u8 addr) +{ + struct j1939_ecu *ecu; + + lockdep_assert_held(&priv->lock); + + if (!j1939_address_is_unicast(addr)) + return NULL; + + ecu = j1939_ecu_find_by_addr_locked(priv, addr); + if (ecu) + j1939_ecu_get(ecu); + + return ecu; +} + +struct j1939_ecu *j1939_ecu_get_by_addr(struct j1939_priv *priv, u8 addr) +{ + struct j1939_ecu *ecu; + + read_lock_bh(&priv->lock); + ecu = j1939_ecu_get_by_addr_locked(priv, addr); + read_unlock_bh(&priv->lock); + + return ecu; +} + +/* get pointer to ecu without increasing ref counter */ +static struct j1939_ecu *j1939_ecu_find_by_name_locked(struct j1939_priv *priv, + name_t name) +{ + struct j1939_ecu *ecu; + + lockdep_assert_held(&priv->lock); + + list_for_each_entry(ecu, &priv->ecus, list) { + if (ecu->name == name) + return ecu; + } + + return NULL; +} + +struct j1939_ecu *j1939_ecu_get_by_name_locked(struct j1939_priv *priv, + name_t name) +{ + struct j1939_ecu *ecu; + + lockdep_assert_held(&priv->lock); + + if (!name) + return NULL; + + ecu = j1939_ecu_find_by_name_locked(priv, name); + if (ecu) + j1939_ecu_get(ecu); + + return ecu; +} + +struct j1939_ecu *j1939_ecu_get_by_name(struct j1939_priv *priv, name_t name) +{ + struct j1939_ecu *ecu; + + read_lock_bh(&priv->lock); + ecu = j1939_ecu_get_by_name_locked(priv, name); + read_unlock_bh(&priv->lock); + + return ecu; +} + +u8 j1939_name_to_addr(struct j1939_priv *priv, name_t name) +{ + struct j1939_ecu *ecu; + int addr = J1939_IDLE_ADDR; + + if (!name) + return J1939_NO_ADDR; + + read_lock_bh(&priv->lock); + ecu = j1939_ecu_find_by_name_locked(priv, name); + if (ecu && j1939_ecu_is_mapped_locked(ecu)) + /* ecu's SA is registered */ + addr = ecu->addr; + + read_unlock_bh(&priv->lock); + + return addr; +} + +/* TX addr/name accounting + * Transport protocol needs to know if a SA is local or not + * These functions originate from userspace manipulating sockets, + * so locking is straigforward + */ + +int j1939_local_ecu_get(struct j1939_priv *priv, name_t name, u8 sa) +{ + struct j1939_ecu *ecu; + int err = 0; + + write_lock_bh(&priv->lock); + + if (j1939_address_is_unicast(sa)) + priv->ents[sa].nusers++; + + if (!name) + goto done; + + ecu = j1939_ecu_get_by_name_locked(priv, name); + if (!ecu) + ecu = j1939_ecu_create_locked(priv, name); + err = PTR_ERR_OR_ZERO(ecu); + if (err) + goto done; + + ecu->nusers++; + /* TODO: do we care if ecu->addr != sa? */ + if (j1939_ecu_is_mapped_locked(ecu)) + /* ecu's sa is active already */ + priv->ents[ecu->addr].nusers++; + + done: + write_unlock_bh(&priv->lock); + + return err; +} + +void j1939_local_ecu_put(struct j1939_priv *priv, name_t name, u8 sa) +{ + struct j1939_ecu *ecu; + + write_lock_bh(&priv->lock); + + if (j1939_address_is_unicast(sa)) + priv->ents[sa].nusers--; + + if (!name) + goto done; + + ecu = j1939_ecu_find_by_name_locked(priv, name); + if (WARN_ON_ONCE(!ecu)) + goto done; + + ecu->nusers--; + /* TODO: do we care if ecu->addr != sa? */ + if (j1939_ecu_is_mapped_locked(ecu)) + /* ecu's sa is active already */ + priv->ents[ecu->addr].nusers--; + j1939_ecu_put(ecu); + + done: + write_unlock_bh(&priv->lock); +} diff --git a/net/can/j1939/j1939-priv.h b/net/can/j1939/j1939-priv.h new file mode 100644 index 000000000..16af1a7f8 --- /dev/null +++ b/net/can/j1939/j1939-priv.h @@ -0,0 +1,343 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +#ifndef _J1939_PRIV_H_ +#define _J1939_PRIV_H_ + +#include <linux/can/j1939.h> +#include <net/sock.h> + +/* Timeout to receive the abort signal over loop back. In case CAN + * bus is open, the timeout should be triggered. + */ +#define J1939_XTP_ABORT_TIMEOUT_MS 500 +#define J1939_SIMPLE_ECHO_TIMEOUT_MS (10 * 1000) + +struct j1939_session; +enum j1939_sk_errqueue_type { + J1939_ERRQUEUE_TX_ACK, + J1939_ERRQUEUE_TX_SCHED, + J1939_ERRQUEUE_TX_ABORT, + J1939_ERRQUEUE_RX_RTS, + J1939_ERRQUEUE_RX_DPO, + J1939_ERRQUEUE_RX_ABORT, +}; + +/* j1939 devices */ +struct j1939_ecu { + struct list_head list; + name_t name; + u8 addr; + + /* indicates that this ecu successfully claimed @sa as its address */ + struct hrtimer ac_timer; + struct kref kref; + struct j1939_priv *priv; + + /* count users, to help transport protocol decide for interaction */ + int nusers; +}; + +struct j1939_priv { + struct list_head ecus; + /* local list entry in priv + * These allow irq (& softirq) context lookups on j1939 devices + * This approach (separate lists) is done as the other 2 alternatives + * are not easier or even wrong + * 1) using the pure kobject methods involves mutexes, which are not + * allowed in irq context. + * 2) duplicating data structures would require a lot of synchronization + * code + * usage: + */ + + /* segments need a lock to protect the above list */ + rwlock_t lock; + + struct net_device *ndev; + + /* list of 256 ecu ptrs, that cache the claimed addresses. + * also protected by the above lock + */ + struct j1939_addr_ent { + struct j1939_ecu *ecu; + /* count users, to help transport protocol */ + int nusers; + } ents[256]; + + struct kref kref; + + /* List of active sessions to prevent start of conflicting + * one. + * + * Do not start two sessions of same type, addresses and + * direction. + */ + struct list_head active_session_list; + + /* protects active_session_list */ + spinlock_t active_session_list_lock; + + unsigned int tp_max_packet_size; + + /* lock for j1939_socks list */ + spinlock_t j1939_socks_lock; + struct list_head j1939_socks; + + struct kref rx_kref; + u32 rx_tskey; +}; + +void j1939_ecu_put(struct j1939_ecu *ecu); + +/* keep the cache of what is local */ +int j1939_local_ecu_get(struct j1939_priv *priv, name_t name, u8 sa); +void j1939_local_ecu_put(struct j1939_priv *priv, name_t name, u8 sa); + +static inline bool j1939_address_is_unicast(u8 addr) +{ + return addr <= J1939_MAX_UNICAST_ADDR; +} + +static inline bool j1939_address_is_idle(u8 addr) +{ + return addr == J1939_IDLE_ADDR; +} + +static inline bool j1939_address_is_valid(u8 addr) +{ + return addr != J1939_NO_ADDR; +} + +static inline bool j1939_pgn_is_pdu1(pgn_t pgn) +{ + /* ignore dp & res bits for this */ + return (pgn & 0xff00) < 0xf000; +} + +/* utility to correctly unmap an ECU */ +void j1939_ecu_unmap_locked(struct j1939_ecu *ecu); +void j1939_ecu_unmap(struct j1939_ecu *ecu); + +u8 j1939_name_to_addr(struct j1939_priv *priv, name_t name); +struct j1939_ecu *j1939_ecu_find_by_addr_locked(struct j1939_priv *priv, + u8 addr); +struct j1939_ecu *j1939_ecu_get_by_addr(struct j1939_priv *priv, u8 addr); +struct j1939_ecu *j1939_ecu_get_by_addr_locked(struct j1939_priv *priv, + u8 addr); +struct j1939_ecu *j1939_ecu_get_by_name(struct j1939_priv *priv, name_t name); +struct j1939_ecu *j1939_ecu_get_by_name_locked(struct j1939_priv *priv, + name_t name); + +enum j1939_transfer_type { + J1939_TP, + J1939_ETP, + J1939_SIMPLE, +}; + +struct j1939_addr { + name_t src_name; + name_t dst_name; + pgn_t pgn; + + u8 sa; + u8 da; + + u8 type; +}; + +/* control buffer of the sk_buff */ +struct j1939_sk_buff_cb { + /* Offset in bytes within one ETP session */ + u32 offset; + + /* for tx, MSG_SYN will be used to sync on sockets */ + u32 msg_flags; + u32 tskey; + + struct j1939_addr addr; + + /* Flags for quick lookups during skb processing. + * These are set in the receive path only. + */ +#define J1939_ECU_LOCAL_SRC BIT(0) +#define J1939_ECU_LOCAL_DST BIT(1) + u8 flags; + + priority_t priority; +}; + +static inline +struct j1939_sk_buff_cb *j1939_skb_to_cb(const struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(struct j1939_sk_buff_cb) > sizeof(skb->cb)); + + return (struct j1939_sk_buff_cb *)skb->cb; +} + +int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb); +bool j1939_sk_recv_match(struct j1939_priv *priv, + struct j1939_sk_buff_cb *skcb); +void j1939_sk_send_loop_abort(struct sock *sk, int err); +void j1939_sk_errqueue(struct j1939_session *session, + enum j1939_sk_errqueue_type type); +void j1939_sk_queue_activate_next(struct j1939_session *session); + +/* stack entries */ +struct j1939_session *j1939_tp_send(struct j1939_priv *priv, + struct sk_buff *skb, size_t size); +int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb); +int j1939_ac_fixup(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_ac_recv(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_simple_recv(struct j1939_priv *priv, struct sk_buff *skb); + +/* network management */ +struct j1939_ecu *j1939_ecu_create_locked(struct j1939_priv *priv, name_t name); + +void j1939_ecu_timer_start(struct j1939_ecu *ecu); +void j1939_ecu_timer_cancel(struct j1939_ecu *ecu); +void j1939_ecu_unmap_all(struct j1939_priv *priv); + +struct j1939_priv *j1939_netdev_start(struct net_device *ndev); +void j1939_netdev_stop(struct j1939_priv *priv); + +void j1939_priv_put(struct j1939_priv *priv); +void j1939_priv_get(struct j1939_priv *priv); + +/* notify/alert all j1939 sockets bound to ifindex */ +void j1939_sk_netdev_event_netdown(struct j1939_priv *priv); +int j1939_cancel_active_session(struct j1939_priv *priv, struct sock *sk); +void j1939_tp_init(struct j1939_priv *priv); + +/* decrement pending skb for a j1939 socket */ +void j1939_sock_pending_del(struct sock *sk); + +enum j1939_session_state { + J1939_SESSION_NEW, + J1939_SESSION_ACTIVE, + /* waiting for abort signal on the bus */ + J1939_SESSION_WAITING_ABORT, + J1939_SESSION_ACTIVE_MAX, + J1939_SESSION_DONE, +}; + +struct j1939_session { + struct j1939_priv *priv; + struct list_head active_session_list_entry; + struct list_head sk_session_queue_entry; + struct kref kref; + struct sock *sk; + + /* ifindex, src, dst, pgn define the session block + * the are _never_ modified after insertion in the list + * this decreases locking problems a _lot_ + */ + struct j1939_sk_buff_cb skcb; + struct sk_buff_head skb_queue; + + /* all tx related stuff (last_txcmd, pkt.tx) + * is protected (modified only) with the txtimer hrtimer + * 'total' & 'block' are never changed, + * last_cmd, last & block are protected by ->lock + * this means that the tx may run after cts is received that should + * have stopped tx, but this time discrepancy is never avoided anyhow + */ + u8 last_cmd, last_txcmd; + bool transmission; + bool extd; + /* Total message size, number of bytes */ + unsigned int total_message_size; + /* Total number of bytes queue from socket to the session */ + unsigned int total_queued_size; + unsigned int tx_retry; + + int err; + u32 tskey; + enum j1939_session_state state; + + /* Packets counters for a (extended) transfer session. The packet is + * maximal of 7 bytes. + */ + struct { + /* total - total number of packets for this session */ + unsigned int total; + /* last - last packet of a transfer block after which + * responder should send ETP.CM_CTS and originator + * ETP.CM_DPO + */ + unsigned int last; + /* tx - number of packets send by originator node. + * this counter can be set back if responder node + * didn't received all packets send by originator. + */ + unsigned int tx; + unsigned int tx_acked; + /* rx - number of packets received */ + unsigned int rx; + /* block - amount of packets expected in one block */ + unsigned int block; + /* dpo - ETP.CM_DPO, Data Packet Offset */ + unsigned int dpo; + } pkt; + struct hrtimer txtimer, rxtimer; +}; + +struct j1939_sock { + struct sock sk; /* must be first to skip with memset */ + struct j1939_priv *priv; + struct list_head list; + +#define J1939_SOCK_BOUND BIT(0) +#define J1939_SOCK_CONNECTED BIT(1) +#define J1939_SOCK_PROMISC BIT(2) +#define J1939_SOCK_ERRQUEUE BIT(3) + int state; + + int ifindex; + struct j1939_addr addr; + struct j1939_filter *filters; + int nfilters; + pgn_t pgn_rx_filter; + + /* j1939 may emit equal PGN (!= equal CAN-id's) out of order + * when transport protocol comes in. + * To allow emitting in order, keep a 'pending' nr. of packets + */ + atomic_t skb_pending; + wait_queue_head_t waitq; + + /* lock for the sk_session_queue list */ + spinlock_t sk_session_queue_lock; + struct list_head sk_session_queue; +}; + +static inline struct j1939_sock *j1939_sk(const struct sock *sk) +{ + return container_of(sk, struct j1939_sock, sk); +} + +void j1939_session_get(struct j1939_session *session); +void j1939_session_put(struct j1939_session *session); +void j1939_session_skb_queue(struct j1939_session *session, + struct sk_buff *skb); +int j1939_session_activate(struct j1939_session *session); +void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec); +void j1939_session_timers_cancel(struct j1939_session *session); + +#define J1939_MIN_TP_PACKET_SIZE 9 +#define J1939_MAX_TP_PACKET_SIZE (7 * 0xff) +#define J1939_MAX_ETP_PACKET_SIZE (7 * 0x00ffffff) + +#define J1939_REGULAR 0 +#define J1939_EXTENDED 1 + +/* CAN protocol */ +extern const struct can_proto j1939_can_proto; + +#endif /* _J1939_PRIV_H_ */ diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c new file mode 100644 index 000000000..ecff1c947 --- /dev/null +++ b/net/can/j1939/main.c @@ -0,0 +1,429 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Pieter Beyens <pieter.beyens@eia.be> +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2018 Protonic, +// Robin van der Gracht <robin@protonic.nl> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +/* Core of can-j1939 that links j1939 to CAN. */ + +#include <linux/can/can-ml.h> +#include <linux/can/core.h> +#include <linux/can/skb.h> +#include <linux/if_arp.h> +#include <linux/module.h> + +#include "j1939-priv.h" + +MODULE_DESCRIPTION("PF_CAN SAE J1939"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("EIA Electronics (Kurt Van Dijck & Pieter Beyens)"); +MODULE_ALIAS("can-proto-" __stringify(CAN_J1939)); + +/* LOWLEVEL CAN interface */ + +/* CAN_HDR: #bytes before can_frame data part */ +#define J1939_CAN_HDR (offsetof(struct can_frame, data)) + +/* CAN_FTR: #bytes beyond data part */ +#define J1939_CAN_FTR (sizeof(struct can_frame) - J1939_CAN_HDR - \ + sizeof(((struct can_frame *)0)->data)) + +/* lowest layer */ +static void j1939_can_recv(struct sk_buff *iskb, void *data) +{ + struct j1939_priv *priv = data; + struct sk_buff *skb; + struct j1939_sk_buff_cb *skcb, *iskcb; + struct can_frame *cf; + + /* make sure we only get Classical CAN frames */ + if (!can_is_can_skb(iskb)) + return; + + /* create a copy of the skb + * j1939 only delivers the real data bytes, + * the header goes into sockaddr. + * j1939 may not touch the incoming skb in such way + */ + skb = skb_clone(iskb, GFP_ATOMIC); + if (!skb) + return; + + j1939_priv_get(priv); + can_skb_set_owner(skb, iskb->sk); + + /* get a pointer to the header of the skb + * the skb payload (pointer) is moved, so that the next skb_data + * returns the actual payload + */ + cf = (void *)skb->data; + skb_pull(skb, J1939_CAN_HDR); + + /* fix length, set to dlc, with 8 maximum */ + skb_trim(skb, min_t(uint8_t, cf->len, 8)); + + /* set addr */ + skcb = j1939_skb_to_cb(skb); + memset(skcb, 0, sizeof(*skcb)); + + iskcb = j1939_skb_to_cb(iskb); + skcb->tskey = iskcb->tskey; + skcb->priority = (cf->can_id >> 26) & 0x7; + skcb->addr.sa = cf->can_id; + skcb->addr.pgn = (cf->can_id >> 8) & J1939_PGN_MAX; + /* set default message type */ + skcb->addr.type = J1939_TP; + + if (!j1939_address_is_valid(skcb->addr.sa)) { + netdev_err_once(priv->ndev, "%s: sa is broadcast address, ignoring!\n", + __func__); + goto done; + } + + if (j1939_pgn_is_pdu1(skcb->addr.pgn)) { + /* Type 1: with destination address */ + skcb->addr.da = skcb->addr.pgn; + /* normalize pgn: strip dst address */ + skcb->addr.pgn &= 0x3ff00; + } else { + /* set broadcast address */ + skcb->addr.da = J1939_NO_ADDR; + } + + /* update localflags */ + read_lock_bh(&priv->lock); + if (j1939_address_is_unicast(skcb->addr.sa) && + priv->ents[skcb->addr.sa].nusers) + skcb->flags |= J1939_ECU_LOCAL_SRC; + if (j1939_address_is_unicast(skcb->addr.da) && + priv->ents[skcb->addr.da].nusers) + skcb->flags |= J1939_ECU_LOCAL_DST; + read_unlock_bh(&priv->lock); + + /* deliver into the j1939 stack ... */ + j1939_ac_recv(priv, skb); + + if (j1939_tp_recv(priv, skb)) + /* this means the transport layer processed the message */ + goto done; + + j1939_simple_recv(priv, skb); + j1939_sk_recv(priv, skb); + done: + j1939_priv_put(priv); + kfree_skb(skb); +} + +/* NETDEV MANAGEMENT */ + +/* values for can_rx_(un)register */ +#define J1939_CAN_ID CAN_EFF_FLAG +#define J1939_CAN_MASK (CAN_EFF_FLAG | CAN_RTR_FLAG) + +static DEFINE_MUTEX(j1939_netdev_lock); + +static struct j1939_priv *j1939_priv_create(struct net_device *ndev) +{ + struct j1939_priv *priv; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return NULL; + + rwlock_init(&priv->lock); + INIT_LIST_HEAD(&priv->ecus); + priv->ndev = ndev; + kref_init(&priv->kref); + kref_init(&priv->rx_kref); + dev_hold(ndev); + + netdev_dbg(priv->ndev, "%s : 0x%p\n", __func__, priv); + + return priv; +} + +static inline void j1939_priv_set(struct net_device *ndev, + struct j1939_priv *priv) +{ + struct can_ml_priv *can_ml = can_get_ml_priv(ndev); + + can_ml->j1939_priv = priv; +} + +static void __j1939_priv_release(struct kref *kref) +{ + struct j1939_priv *priv = container_of(kref, struct j1939_priv, kref); + struct net_device *ndev = priv->ndev; + + netdev_dbg(priv->ndev, "%s: 0x%p\n", __func__, priv); + + WARN_ON_ONCE(!list_empty(&priv->active_session_list)); + WARN_ON_ONCE(!list_empty(&priv->ecus)); + WARN_ON_ONCE(!list_empty(&priv->j1939_socks)); + + dev_put(ndev); + kfree(priv); +} + +void j1939_priv_put(struct j1939_priv *priv) +{ + kref_put(&priv->kref, __j1939_priv_release); +} + +void j1939_priv_get(struct j1939_priv *priv) +{ + kref_get(&priv->kref); +} + +static int j1939_can_rx_register(struct j1939_priv *priv) +{ + struct net_device *ndev = priv->ndev; + int ret; + + j1939_priv_get(priv); + ret = can_rx_register(dev_net(ndev), ndev, J1939_CAN_ID, J1939_CAN_MASK, + j1939_can_recv, priv, "j1939", NULL); + if (ret < 0) { + j1939_priv_put(priv); + return ret; + } + + return 0; +} + +static void j1939_can_rx_unregister(struct j1939_priv *priv) +{ + struct net_device *ndev = priv->ndev; + + can_rx_unregister(dev_net(ndev), ndev, J1939_CAN_ID, J1939_CAN_MASK, + j1939_can_recv, priv); + + /* The last reference of priv is dropped by the RCU deferred + * j1939_sk_sock_destruct() of the last socket, so we can + * safely drop this reference here. + */ + j1939_priv_put(priv); +} + +static void __j1939_rx_release(struct kref *kref) + __releases(&j1939_netdev_lock) +{ + struct j1939_priv *priv = container_of(kref, struct j1939_priv, + rx_kref); + + j1939_can_rx_unregister(priv); + j1939_ecu_unmap_all(priv); + j1939_priv_set(priv->ndev, NULL); + mutex_unlock(&j1939_netdev_lock); +} + +/* get pointer to priv without increasing ref counter */ +static inline struct j1939_priv *j1939_ndev_to_priv(struct net_device *ndev) +{ + struct can_ml_priv *can_ml = can_get_ml_priv(ndev); + + return can_ml->j1939_priv; +} + +static struct j1939_priv *j1939_priv_get_by_ndev_locked(struct net_device *ndev) +{ + struct j1939_priv *priv; + + lockdep_assert_held(&j1939_netdev_lock); + + priv = j1939_ndev_to_priv(ndev); + if (priv) + j1939_priv_get(priv); + + return priv; +} + +static struct j1939_priv *j1939_priv_get_by_ndev(struct net_device *ndev) +{ + struct j1939_priv *priv; + + mutex_lock(&j1939_netdev_lock); + priv = j1939_priv_get_by_ndev_locked(ndev); + mutex_unlock(&j1939_netdev_lock); + + return priv; +} + +struct j1939_priv *j1939_netdev_start(struct net_device *ndev) +{ + struct j1939_priv *priv, *priv_new; + int ret; + + mutex_lock(&j1939_netdev_lock); + priv = j1939_priv_get_by_ndev_locked(ndev); + if (priv) { + kref_get(&priv->rx_kref); + mutex_unlock(&j1939_netdev_lock); + return priv; + } + mutex_unlock(&j1939_netdev_lock); + + priv = j1939_priv_create(ndev); + if (!priv) + return ERR_PTR(-ENOMEM); + + j1939_tp_init(priv); + spin_lock_init(&priv->j1939_socks_lock); + INIT_LIST_HEAD(&priv->j1939_socks); + + mutex_lock(&j1939_netdev_lock); + priv_new = j1939_priv_get_by_ndev_locked(ndev); + if (priv_new) { + /* Someone was faster than us, use their priv and roll + * back our's. + */ + kref_get(&priv_new->rx_kref); + mutex_unlock(&j1939_netdev_lock); + dev_put(ndev); + kfree(priv); + return priv_new; + } + j1939_priv_set(ndev, priv); + + ret = j1939_can_rx_register(priv); + if (ret < 0) + goto out_priv_put; + + mutex_unlock(&j1939_netdev_lock); + return priv; + + out_priv_put: + j1939_priv_set(ndev, NULL); + mutex_unlock(&j1939_netdev_lock); + + dev_put(ndev); + kfree(priv); + + return ERR_PTR(ret); +} + +void j1939_netdev_stop(struct j1939_priv *priv) +{ + kref_put_mutex(&priv->rx_kref, __j1939_rx_release, &j1939_netdev_lock); + j1939_priv_put(priv); +} + +int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb) +{ + int ret, dlc; + canid_t canid; + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct can_frame *cf; + + /* apply sanity checks */ + if (j1939_pgn_is_pdu1(skcb->addr.pgn)) + skcb->addr.pgn &= J1939_PGN_PDU1_MAX; + else + skcb->addr.pgn &= J1939_PGN_MAX; + + if (skcb->priority > 7) + skcb->priority = 6; + + ret = j1939_ac_fixup(priv, skb); + if (unlikely(ret)) + goto failed; + dlc = skb->len; + + /* re-claim the CAN_HDR from the SKB */ + cf = skb_push(skb, J1939_CAN_HDR); + + /* initialize header structure */ + memset(cf, 0, J1939_CAN_HDR); + + /* make it a full can frame again */ + skb_put(skb, J1939_CAN_FTR + (8 - dlc)); + + canid = CAN_EFF_FLAG | + (skcb->priority << 26) | + (skcb->addr.pgn << 8) | + skcb->addr.sa; + if (j1939_pgn_is_pdu1(skcb->addr.pgn)) + canid |= skcb->addr.da << 8; + + cf->can_id = canid; + cf->len = dlc; + + return can_send(skb, 1); + + failed: + kfree_skb(skb); + return ret; +} + +static int j1939_netdev_notify(struct notifier_block *nb, + unsigned long msg, void *data) +{ + struct net_device *ndev = netdev_notifier_info_to_dev(data); + struct can_ml_priv *can_ml = can_get_ml_priv(ndev); + struct j1939_priv *priv; + + if (!can_ml) + goto notify_done; + + priv = j1939_priv_get_by_ndev(ndev); + if (!priv) + goto notify_done; + + switch (msg) { + case NETDEV_DOWN: + j1939_cancel_active_session(priv, NULL); + j1939_sk_netdev_event_netdown(priv); + j1939_ecu_unmap_all(priv); + break; + } + + j1939_priv_put(priv); + +notify_done: + return NOTIFY_DONE; +} + +static struct notifier_block j1939_netdev_notifier = { + .notifier_call = j1939_netdev_notify, +}; + +/* MODULE interface */ +static __init int j1939_module_init(void) +{ + int ret; + + pr_info("can: SAE J1939\n"); + + ret = register_netdevice_notifier(&j1939_netdev_notifier); + if (ret) + goto fail_notifier; + + ret = can_proto_register(&j1939_can_proto); + if (ret < 0) { + pr_err("can: registration of j1939 protocol failed\n"); + goto fail_sk; + } + + return 0; + + fail_sk: + unregister_netdevice_notifier(&j1939_netdev_notifier); + fail_notifier: + return ret; +} + +static __exit void j1939_module_exit(void) +{ + can_proto_unregister(&j1939_can_proto); + + unregister_netdevice_notifier(&j1939_netdev_notifier); +} + +module_init(j1939_module_init); +module_exit(j1939_module_exit); diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c new file mode 100644 index 000000000..b28c976f5 --- /dev/null +++ b/net/can/j1939/socket.c @@ -0,0 +1,1325 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Pieter Beyens <pieter.beyens@eia.be> +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2018 Protonic, +// Robin van der Gracht <robin@protonic.nl> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/can/can-ml.h> +#include <linux/can/core.h> +#include <linux/can/skb.h> +#include <linux/errqueue.h> +#include <linux/if_arp.h> + +#include "j1939-priv.h" + +#define J1939_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.j1939) + +/* conversion function between struct sock::sk_priority from linux and + * j1939 priority field + */ +static inline priority_t j1939_prio(u32 sk_priority) +{ + sk_priority = min(sk_priority, 7U); + + return 7 - sk_priority; +} + +static inline u32 j1939_to_sk_priority(priority_t prio) +{ + return 7 - prio; +} + +/* function to see if pgn is to be evaluated */ +static inline bool j1939_pgn_is_valid(pgn_t pgn) +{ + return pgn <= J1939_PGN_MAX; +} + +/* test function to avoid non-zero DA placeholder for pdu1 pgn's */ +static inline bool j1939_pgn_is_clean_pdu(pgn_t pgn) +{ + if (j1939_pgn_is_pdu1(pgn)) + return !(pgn & 0xff); + else + return true; +} + +static inline void j1939_sock_pending_add(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + atomic_inc(&jsk->skb_pending); +} + +static int j1939_sock_pending_get(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + return atomic_read(&jsk->skb_pending); +} + +void j1939_sock_pending_del(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + /* atomic_dec_return returns the new value */ + if (!atomic_dec_return(&jsk->skb_pending)) + wake_up(&jsk->waitq); /* no pending SKB's */ +} + +static void j1939_jsk_add(struct j1939_priv *priv, struct j1939_sock *jsk) +{ + jsk->state |= J1939_SOCK_BOUND; + j1939_priv_get(priv); + + spin_lock_bh(&priv->j1939_socks_lock); + list_add_tail(&jsk->list, &priv->j1939_socks); + spin_unlock_bh(&priv->j1939_socks_lock); +} + +static void j1939_jsk_del(struct j1939_priv *priv, struct j1939_sock *jsk) +{ + spin_lock_bh(&priv->j1939_socks_lock); + list_del_init(&jsk->list); + spin_unlock_bh(&priv->j1939_socks_lock); + + j1939_priv_put(priv); + jsk->state &= ~J1939_SOCK_BOUND; +} + +static bool j1939_sk_queue_session(struct j1939_session *session) +{ + struct j1939_sock *jsk = j1939_sk(session->sk); + bool empty; + + spin_lock_bh(&jsk->sk_session_queue_lock); + empty = list_empty(&jsk->sk_session_queue); + j1939_session_get(session); + list_add_tail(&session->sk_session_queue_entry, &jsk->sk_session_queue); + spin_unlock_bh(&jsk->sk_session_queue_lock); + j1939_sock_pending_add(&jsk->sk); + + return empty; +} + +static struct +j1939_session *j1939_sk_get_incomplete_session(struct j1939_sock *jsk) +{ + struct j1939_session *session = NULL; + + spin_lock_bh(&jsk->sk_session_queue_lock); + if (!list_empty(&jsk->sk_session_queue)) { + session = list_last_entry(&jsk->sk_session_queue, + struct j1939_session, + sk_session_queue_entry); + if (session->total_queued_size == session->total_message_size) + session = NULL; + else + j1939_session_get(session); + } + spin_unlock_bh(&jsk->sk_session_queue_lock); + + return session; +} + +static void j1939_sk_queue_drop_all(struct j1939_priv *priv, + struct j1939_sock *jsk, int err) +{ + struct j1939_session *session, *tmp; + + netdev_dbg(priv->ndev, "%s: err: %i\n", __func__, err); + spin_lock_bh(&jsk->sk_session_queue_lock); + list_for_each_entry_safe(session, tmp, &jsk->sk_session_queue, + sk_session_queue_entry) { + list_del_init(&session->sk_session_queue_entry); + session->err = err; + j1939_session_put(session); + } + spin_unlock_bh(&jsk->sk_session_queue_lock); +} + +static void j1939_sk_queue_activate_next_locked(struct j1939_session *session) +{ + struct j1939_sock *jsk; + struct j1939_session *first; + int err; + + /* RX-Session don't have a socket (yet) */ + if (!session->sk) + return; + + jsk = j1939_sk(session->sk); + lockdep_assert_held(&jsk->sk_session_queue_lock); + + err = session->err; + + first = list_first_entry_or_null(&jsk->sk_session_queue, + struct j1939_session, + sk_session_queue_entry); + + /* Some else has already activated the next session */ + if (first != session) + return; + +activate_next: + list_del_init(&first->sk_session_queue_entry); + j1939_session_put(first); + first = list_first_entry_or_null(&jsk->sk_session_queue, + struct j1939_session, + sk_session_queue_entry); + if (!first) + return; + + if (j1939_session_activate(first)) { + netdev_warn_once(first->priv->ndev, + "%s: 0x%p: Identical session is already activated.\n", + __func__, first); + first->err = -EBUSY; + goto activate_next; + } else { + /* Give receiver some time (arbitrary chosen) to recover */ + int time_ms = 0; + + if (err) + time_ms = 10 + get_random_u32_below(16); + + j1939_tp_schedule_txtimer(first, time_ms); + } +} + +void j1939_sk_queue_activate_next(struct j1939_session *session) +{ + struct j1939_sock *jsk; + + if (!session->sk) + return; + + jsk = j1939_sk(session->sk); + + spin_lock_bh(&jsk->sk_session_queue_lock); + j1939_sk_queue_activate_next_locked(session); + spin_unlock_bh(&jsk->sk_session_queue_lock); +} + +static bool j1939_sk_match_dst(struct j1939_sock *jsk, + const struct j1939_sk_buff_cb *skcb) +{ + if ((jsk->state & J1939_SOCK_PROMISC)) + return true; + + /* Destination address filter */ + if (jsk->addr.src_name && skcb->addr.dst_name) { + if (jsk->addr.src_name != skcb->addr.dst_name) + return false; + } else { + /* receive (all sockets) if + * - all packages that match our bind() address + * - all broadcast on a socket if SO_BROADCAST + * is set + */ + if (j1939_address_is_unicast(skcb->addr.da)) { + if (jsk->addr.sa != skcb->addr.da) + return false; + } else if (!sock_flag(&jsk->sk, SOCK_BROADCAST)) { + /* receiving broadcast without SO_BROADCAST + * flag is not allowed + */ + return false; + } + } + + /* Source address filter */ + if (jsk->state & J1939_SOCK_CONNECTED) { + /* receive (all sockets) if + * - all packages that match our connect() name or address + */ + if (jsk->addr.dst_name && skcb->addr.src_name) { + if (jsk->addr.dst_name != skcb->addr.src_name) + return false; + } else { + if (jsk->addr.da != skcb->addr.sa) + return false; + } + } + + /* PGN filter */ + if (j1939_pgn_is_valid(jsk->pgn_rx_filter) && + jsk->pgn_rx_filter != skcb->addr.pgn) + return false; + + return true; +} + +/* matches skb control buffer (addr) with a j1939 filter */ +static bool j1939_sk_match_filter(struct j1939_sock *jsk, + const struct j1939_sk_buff_cb *skcb) +{ + const struct j1939_filter *f = jsk->filters; + int nfilter = jsk->nfilters; + + if (!nfilter) + /* receive all when no filters are assigned */ + return true; + + for (; nfilter; ++f, --nfilter) { + if ((skcb->addr.pgn & f->pgn_mask) != f->pgn) + continue; + if ((skcb->addr.sa & f->addr_mask) != f->addr) + continue; + if ((skcb->addr.src_name & f->name_mask) != f->name) + continue; + return true; + } + return false; +} + +static bool j1939_sk_recv_match_one(struct j1939_sock *jsk, + const struct j1939_sk_buff_cb *skcb) +{ + if (!(jsk->state & J1939_SOCK_BOUND)) + return false; + + if (!j1939_sk_match_dst(jsk, skcb)) + return false; + + if (!j1939_sk_match_filter(jsk, skcb)) + return false; + + return true; +} + +static void j1939_sk_recv_one(struct j1939_sock *jsk, struct sk_buff *oskb) +{ + const struct j1939_sk_buff_cb *oskcb = j1939_skb_to_cb(oskb); + struct j1939_sk_buff_cb *skcb; + struct sk_buff *skb; + + if (oskb->sk == &jsk->sk) + return; + + if (!j1939_sk_recv_match_one(jsk, oskcb)) + return; + + skb = skb_clone(oskb, GFP_ATOMIC); + if (!skb) { + pr_warn("skb clone failed\n"); + return; + } + can_skb_set_owner(skb, oskb->sk); + + skcb = j1939_skb_to_cb(skb); + skcb->msg_flags &= ~(MSG_DONTROUTE); + if (skb->sk) + skcb->msg_flags |= MSG_DONTROUTE; + + if (sock_queue_rcv_skb(&jsk->sk, skb) < 0) + kfree_skb(skb); +} + +bool j1939_sk_recv_match(struct j1939_priv *priv, struct j1939_sk_buff_cb *skcb) +{ + struct j1939_sock *jsk; + bool match = false; + + spin_lock_bh(&priv->j1939_socks_lock); + list_for_each_entry(jsk, &priv->j1939_socks, list) { + match = j1939_sk_recv_match_one(jsk, skcb); + if (match) + break; + } + spin_unlock_bh(&priv->j1939_socks_lock); + + return match; +} + +void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sock *jsk; + + spin_lock_bh(&priv->j1939_socks_lock); + list_for_each_entry(jsk, &priv->j1939_socks, list) { + j1939_sk_recv_one(jsk, skb); + } + spin_unlock_bh(&priv->j1939_socks_lock); +} + +static void j1939_sk_sock_destruct(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + /* This function will be called by the generic networking code, when + * the socket is ultimately closed (sk->sk_destruct). + * + * The race between + * - processing a received CAN frame + * (can_receive -> j1939_can_recv) + * and accessing j1939_priv + * ... and ... + * - closing a socket + * (j1939_can_rx_unregister -> can_rx_unregister) + * and calling the final j1939_priv_put() + * + * is avoided by calling the final j1939_priv_put() from this + * RCU deferred cleanup call. + */ + if (jsk->priv) { + j1939_priv_put(jsk->priv); + jsk->priv = NULL; + } + + /* call generic CAN sock destruct */ + can_sock_destruct(sk); +} + +static int j1939_sk_init(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + /* Ensure that "sk" is first member in "struct j1939_sock", so that we + * can skip it during memset(). + */ + BUILD_BUG_ON(offsetof(struct j1939_sock, sk) != 0); + memset((void *)jsk + sizeof(jsk->sk), 0x0, + sizeof(*jsk) - sizeof(jsk->sk)); + + INIT_LIST_HEAD(&jsk->list); + init_waitqueue_head(&jsk->waitq); + jsk->sk.sk_priority = j1939_to_sk_priority(6); + jsk->sk.sk_reuse = 1; /* per default */ + jsk->addr.sa = J1939_NO_ADDR; + jsk->addr.da = J1939_NO_ADDR; + jsk->addr.pgn = J1939_NO_PGN; + jsk->pgn_rx_filter = J1939_NO_PGN; + atomic_set(&jsk->skb_pending, 0); + spin_lock_init(&jsk->sk_session_queue_lock); + INIT_LIST_HEAD(&jsk->sk_session_queue); + + /* j1939_sk_sock_destruct() depends on SOCK_RCU_FREE flag */ + sock_set_flag(sk, SOCK_RCU_FREE); + sk->sk_destruct = j1939_sk_sock_destruct; + sk->sk_protocol = CAN_J1939; + + return 0; +} + +static int j1939_sk_sanity_check(struct sockaddr_can *addr, int len) +{ + if (!addr) + return -EDESTADDRREQ; + if (len < J1939_MIN_NAMELEN) + return -EINVAL; + if (addr->can_family != AF_CAN) + return -EINVAL; + if (!addr->can_ifindex) + return -ENODEV; + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) && + !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) + return -EINVAL; + + return 0; +} + +static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct j1939_sock *jsk = j1939_sk(sock->sk); + struct j1939_priv *priv; + struct sock *sk; + struct net *net; + int ret = 0; + + ret = j1939_sk_sanity_check(addr, len); + if (ret) + return ret; + + lock_sock(sock->sk); + + priv = jsk->priv; + sk = sock->sk; + net = sock_net(sk); + + /* Already bound to an interface? */ + if (jsk->state & J1939_SOCK_BOUND) { + /* A re-bind() to a different interface is not + * supported. + */ + if (jsk->ifindex != addr->can_ifindex) { + ret = -EINVAL; + goto out_release_sock; + } + + /* drop old references */ + j1939_jsk_del(priv, jsk); + j1939_local_ecu_put(priv, jsk->addr.src_name, jsk->addr.sa); + } else { + struct can_ml_priv *can_ml; + struct net_device *ndev; + + ndev = dev_get_by_index(net, addr->can_ifindex); + if (!ndev) { + ret = -ENODEV; + goto out_release_sock; + } + + can_ml = can_get_ml_priv(ndev); + if (!can_ml) { + dev_put(ndev); + ret = -ENODEV; + goto out_release_sock; + } + + if (!(ndev->flags & IFF_UP)) { + dev_put(ndev); + ret = -ENETDOWN; + goto out_release_sock; + } + + priv = j1939_netdev_start(ndev); + dev_put(ndev); + if (IS_ERR(priv)) { + ret = PTR_ERR(priv); + goto out_release_sock; + } + + jsk->ifindex = addr->can_ifindex; + + /* the corresponding j1939_priv_put() is called via + * sk->sk_destruct, which points to j1939_sk_sock_destruct() + */ + j1939_priv_get(priv); + jsk->priv = priv; + } + + /* set default transmit pgn */ + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn)) + jsk->pgn_rx_filter = addr->can_addr.j1939.pgn; + jsk->addr.src_name = addr->can_addr.j1939.name; + jsk->addr.sa = addr->can_addr.j1939.addr; + + /* get new references */ + ret = j1939_local_ecu_get(priv, jsk->addr.src_name, jsk->addr.sa); + if (ret) { + j1939_netdev_stop(priv); + goto out_release_sock; + } + + j1939_jsk_add(priv, jsk); + + out_release_sock: /* fall through */ + release_sock(sock->sk); + + return ret; +} + +static int j1939_sk_connect(struct socket *sock, struct sockaddr *uaddr, + int len, int flags) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct j1939_sock *jsk = j1939_sk(sock->sk); + int ret = 0; + + ret = j1939_sk_sanity_check(addr, len); + if (ret) + return ret; + + lock_sock(sock->sk); + + /* bind() before connect() is mandatory */ + if (!(jsk->state & J1939_SOCK_BOUND)) { + ret = -EINVAL; + goto out_release_sock; + } + + /* A connect() to a different interface is not supported. */ + if (jsk->ifindex != addr->can_ifindex) { + ret = -EINVAL; + goto out_release_sock; + } + + if (!addr->can_addr.j1939.name && + addr->can_addr.j1939.addr == J1939_NO_ADDR && + !sock_flag(&jsk->sk, SOCK_BROADCAST)) { + /* broadcast, but SO_BROADCAST not set */ + ret = -EACCES; + goto out_release_sock; + } + + jsk->addr.dst_name = addr->can_addr.j1939.name; + jsk->addr.da = addr->can_addr.j1939.addr; + + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn)) + jsk->addr.pgn = addr->can_addr.j1939.pgn; + + jsk->state |= J1939_SOCK_CONNECTED; + + out_release_sock: /* fall through */ + release_sock(sock->sk); + + return ret; +} + +static void j1939_sk_sock2sockaddr_can(struct sockaddr_can *addr, + const struct j1939_sock *jsk, int peer) +{ + /* There are two holes (2 bytes and 3 bytes) to clear to avoid + * leaking kernel information to user space. + */ + memset(addr, 0, J1939_MIN_NAMELEN); + + addr->can_family = AF_CAN; + addr->can_ifindex = jsk->ifindex; + addr->can_addr.j1939.pgn = jsk->addr.pgn; + if (peer) { + addr->can_addr.j1939.name = jsk->addr.dst_name; + addr->can_addr.j1939.addr = jsk->addr.da; + } else { + addr->can_addr.j1939.name = jsk->addr.src_name; + addr->can_addr.j1939.addr = jsk->addr.sa; + } +} + +static int j1939_sk_getname(struct socket *sock, struct sockaddr *uaddr, + int peer) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct sock *sk = sock->sk; + struct j1939_sock *jsk = j1939_sk(sk); + int ret = 0; + + lock_sock(sk); + + if (peer && !(jsk->state & J1939_SOCK_CONNECTED)) { + ret = -EADDRNOTAVAIL; + goto failure; + } + + j1939_sk_sock2sockaddr_can(addr, jsk, peer); + ret = J1939_MIN_NAMELEN; + + failure: + release_sock(sk); + + return ret; +} + +static int j1939_sk_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct j1939_sock *jsk; + + if (!sk) + return 0; + + lock_sock(sk); + jsk = j1939_sk(sk); + + if (jsk->state & J1939_SOCK_BOUND) { + struct j1939_priv *priv = jsk->priv; + + if (wait_event_interruptible(jsk->waitq, + !j1939_sock_pending_get(&jsk->sk))) { + j1939_cancel_active_session(priv, sk); + j1939_sk_queue_drop_all(priv, jsk, ESHUTDOWN); + } + + j1939_jsk_del(priv, jsk); + + j1939_local_ecu_put(priv, jsk->addr.src_name, + jsk->addr.sa); + + j1939_netdev_stop(priv); + } + + kfree(jsk->filters); + sock_orphan(sk); + sock->sk = NULL; + + release_sock(sk); + sock_put(sk); + + return 0; +} + +static int j1939_sk_setsockopt_flag(struct j1939_sock *jsk, sockptr_t optval, + unsigned int optlen, int flag) +{ + int tmp; + + if (optlen != sizeof(tmp)) + return -EINVAL; + if (copy_from_sockptr(&tmp, optval, optlen)) + return -EFAULT; + lock_sock(&jsk->sk); + if (tmp) + jsk->state |= flag; + else + jsk->state &= ~flag; + release_sock(&jsk->sk); + return tmp; +} + +static int j1939_sk_setsockopt(struct socket *sock, int level, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct sock *sk = sock->sk; + struct j1939_sock *jsk = j1939_sk(sk); + int tmp, count = 0, ret = 0; + struct j1939_filter *filters = NULL, *ofilters; + + if (level != SOL_CAN_J1939) + return -EINVAL; + + switch (optname) { + case SO_J1939_FILTER: + if (!sockptr_is_null(optval) && optlen != 0) { + struct j1939_filter *f; + int c; + + if (optlen % sizeof(*filters) != 0) + return -EINVAL; + + if (optlen > J1939_FILTER_MAX * + sizeof(struct j1939_filter)) + return -EINVAL; + + count = optlen / sizeof(*filters); + filters = memdup_sockptr(optval, optlen); + if (IS_ERR(filters)) + return PTR_ERR(filters); + + for (f = filters, c = count; c; f++, c--) { + f->name &= f->name_mask; + f->pgn &= f->pgn_mask; + f->addr &= f->addr_mask; + } + } + + lock_sock(&jsk->sk); + ofilters = jsk->filters; + jsk->filters = filters; + jsk->nfilters = count; + release_sock(&jsk->sk); + kfree(ofilters); + return 0; + case SO_J1939_PROMISC: + return j1939_sk_setsockopt_flag(jsk, optval, optlen, + J1939_SOCK_PROMISC); + case SO_J1939_ERRQUEUE: + ret = j1939_sk_setsockopt_flag(jsk, optval, optlen, + J1939_SOCK_ERRQUEUE); + if (ret < 0) + return ret; + + if (!(jsk->state & J1939_SOCK_ERRQUEUE)) + skb_queue_purge(&sk->sk_error_queue); + return ret; + case SO_J1939_SEND_PRIO: + if (optlen != sizeof(tmp)) + return -EINVAL; + if (copy_from_sockptr(&tmp, optval, optlen)) + return -EFAULT; + if (tmp < 0 || tmp > 7) + return -EDOM; + if (tmp < 2 && !capable(CAP_NET_ADMIN)) + return -EPERM; + lock_sock(&jsk->sk); + jsk->sk.sk_priority = j1939_to_sk_priority(tmp); + release_sock(&jsk->sk); + return 0; + default: + return -ENOPROTOOPT; + } +} + +static int j1939_sk_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = sock->sk; + struct j1939_sock *jsk = j1939_sk(sk); + int ret, ulen; + /* set defaults for using 'int' properties */ + int tmp = 0; + int len = sizeof(tmp); + void *val = &tmp; + + if (level != SOL_CAN_J1939) + return -EINVAL; + if (get_user(ulen, optlen)) + return -EFAULT; + if (ulen < 0) + return -EINVAL; + + lock_sock(&jsk->sk); + switch (optname) { + case SO_J1939_PROMISC: + tmp = (jsk->state & J1939_SOCK_PROMISC) ? 1 : 0; + break; + case SO_J1939_ERRQUEUE: + tmp = (jsk->state & J1939_SOCK_ERRQUEUE) ? 1 : 0; + break; + case SO_J1939_SEND_PRIO: + tmp = j1939_prio(jsk->sk.sk_priority); + break; + default: + ret = -ENOPROTOOPT; + goto no_copy; + } + + /* copy to user, based on 'len' & 'val' + * but most sockopt's are 'int' properties, and have 'len' & 'val' + * left unchanged, but instead modified 'tmp' + */ + if (len > ulen) + ret = -EFAULT; + else if (put_user(len, optlen)) + ret = -EFAULT; + else if (copy_to_user(optval, val, len)) + ret = -EFAULT; + else + ret = 0; + no_copy: + release_sock(&jsk->sk); + return ret; +} + +static int j1939_sk_recvmsg(struct socket *sock, struct msghdr *msg, + size_t size, int flags) +{ + struct sock *sk = sock->sk; + struct sk_buff *skb; + struct j1939_sk_buff_cb *skcb; + int ret = 0; + + if (flags & ~(MSG_DONTWAIT | MSG_ERRQUEUE | MSG_CMSG_COMPAT)) + return -EINVAL; + + if (flags & MSG_ERRQUEUE) + return sock_recv_errqueue(sock->sk, msg, size, SOL_CAN_J1939, + SCM_J1939_ERRQUEUE); + + skb = skb_recv_datagram(sk, flags, &ret); + if (!skb) + return ret; + + if (size < skb->len) + msg->msg_flags |= MSG_TRUNC; + else + size = skb->len; + + ret = memcpy_to_msg(msg, skb->data, size); + if (ret < 0) { + skb_free_datagram(sk, skb); + return ret; + } + + skcb = j1939_skb_to_cb(skb); + if (j1939_address_is_valid(skcb->addr.da)) + put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_ADDR, + sizeof(skcb->addr.da), &skcb->addr.da); + + if (skcb->addr.dst_name) + put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_NAME, + sizeof(skcb->addr.dst_name), &skcb->addr.dst_name); + + put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_PRIO, + sizeof(skcb->priority), &skcb->priority); + + if (msg->msg_name) { + struct sockaddr_can *paddr = msg->msg_name; + + msg->msg_namelen = J1939_MIN_NAMELEN; + memset(msg->msg_name, 0, msg->msg_namelen); + paddr->can_family = AF_CAN; + paddr->can_ifindex = skb->skb_iif; + paddr->can_addr.j1939.name = skcb->addr.src_name; + paddr->can_addr.j1939.addr = skcb->addr.sa; + paddr->can_addr.j1939.pgn = skcb->addr.pgn; + } + + sock_recv_cmsgs(msg, sk, skb); + msg->msg_flags |= skcb->msg_flags; + skb_free_datagram(sk, skb); + + return size; +} + +static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev, + struct sock *sk, + struct msghdr *msg, size_t size, + int *errcode) +{ + struct j1939_sock *jsk = j1939_sk(sk); + struct j1939_sk_buff_cb *skcb; + struct sk_buff *skb; + int ret; + + skb = sock_alloc_send_skb(sk, + size + + sizeof(struct can_frame) - + sizeof(((struct can_frame *)NULL)->data) + + sizeof(struct can_skb_priv), + msg->msg_flags & MSG_DONTWAIT, &ret); + if (!skb) + goto failure; + + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = ndev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + skb_reserve(skb, offsetof(struct can_frame, data)); + + ret = memcpy_from_msg(skb_put(skb, size), msg, size); + if (ret < 0) + goto free_skb; + + skb->dev = ndev; + + skcb = j1939_skb_to_cb(skb); + memset(skcb, 0, sizeof(*skcb)); + skcb->addr = jsk->addr; + skcb->priority = j1939_prio(sk->sk_priority); + + if (msg->msg_name) { + struct sockaddr_can *addr = msg->msg_name; + + if (addr->can_addr.j1939.name || + addr->can_addr.j1939.addr != J1939_NO_ADDR) { + skcb->addr.dst_name = addr->can_addr.j1939.name; + skcb->addr.da = addr->can_addr.j1939.addr; + } + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn)) + skcb->addr.pgn = addr->can_addr.j1939.pgn; + } + + *errcode = ret; + return skb; + +free_skb: + kfree_skb(skb); +failure: + *errcode = ret; + return NULL; +} + +static size_t j1939_sk_opt_stats_get_size(enum j1939_sk_errqueue_type type) +{ + switch (type) { + case J1939_ERRQUEUE_RX_RTS: + return + nla_total_size(sizeof(u32)) + /* J1939_NLA_TOTAL_SIZE */ + nla_total_size(sizeof(u32)) + /* J1939_NLA_PGN */ + nla_total_size(sizeof(u64)) + /* J1939_NLA_SRC_NAME */ + nla_total_size(sizeof(u64)) + /* J1939_NLA_DEST_NAME */ + nla_total_size(sizeof(u8)) + /* J1939_NLA_SRC_ADDR */ + nla_total_size(sizeof(u8)) + /* J1939_NLA_DEST_ADDR */ + 0; + default: + return + nla_total_size(sizeof(u32)) + /* J1939_NLA_BYTES_ACKED */ + 0; + } +} + +static struct sk_buff * +j1939_sk_get_timestamping_opt_stats(struct j1939_session *session, + enum j1939_sk_errqueue_type type) +{ + struct sk_buff *stats; + u32 size; + + stats = alloc_skb(j1939_sk_opt_stats_get_size(type), GFP_ATOMIC); + if (!stats) + return NULL; + + if (session->skcb.addr.type == J1939_SIMPLE) + size = session->total_message_size; + else + size = min(session->pkt.tx_acked * 7, + session->total_message_size); + + switch (type) { + case J1939_ERRQUEUE_RX_RTS: + nla_put_u32(stats, J1939_NLA_TOTAL_SIZE, + session->total_message_size); + nla_put_u32(stats, J1939_NLA_PGN, + session->skcb.addr.pgn); + nla_put_u64_64bit(stats, J1939_NLA_SRC_NAME, + session->skcb.addr.src_name, J1939_NLA_PAD); + nla_put_u64_64bit(stats, J1939_NLA_DEST_NAME, + session->skcb.addr.dst_name, J1939_NLA_PAD); + nla_put_u8(stats, J1939_NLA_SRC_ADDR, + session->skcb.addr.sa); + nla_put_u8(stats, J1939_NLA_DEST_ADDR, + session->skcb.addr.da); + break; + default: + nla_put_u32(stats, J1939_NLA_BYTES_ACKED, size); + } + + return stats; +} + +static void __j1939_sk_errqueue(struct j1939_session *session, struct sock *sk, + enum j1939_sk_errqueue_type type) +{ + struct j1939_priv *priv = session->priv; + struct j1939_sock *jsk; + struct sock_exterr_skb *serr; + struct sk_buff *skb; + char *state = "UNK"; + u32 tsflags; + int err; + + jsk = j1939_sk(sk); + + if (!(jsk->state & J1939_SOCK_ERRQUEUE)) + return; + + tsflags = READ_ONCE(sk->sk_tsflags); + switch (type) { + case J1939_ERRQUEUE_TX_ACK: + if (!(tsflags & SOF_TIMESTAMPING_TX_ACK)) + return; + break; + case J1939_ERRQUEUE_TX_SCHED: + if (!(tsflags & SOF_TIMESTAMPING_TX_SCHED)) + return; + break; + case J1939_ERRQUEUE_TX_ABORT: + break; + case J1939_ERRQUEUE_RX_RTS: + fallthrough; + case J1939_ERRQUEUE_RX_DPO: + fallthrough; + case J1939_ERRQUEUE_RX_ABORT: + if (!(tsflags & SOF_TIMESTAMPING_RX_SOFTWARE)) + return; + break; + default: + netdev_err(priv->ndev, "Unknown errqueue type %i\n", type); + } + + skb = j1939_sk_get_timestamping_opt_stats(session, type); + if (!skb) + return; + + skb->tstamp = ktime_get_real(); + + BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb)); + + serr = SKB_EXT_ERR(skb); + memset(serr, 0, sizeof(*serr)); + switch (type) { + case J1939_ERRQUEUE_TX_ACK: + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_info = SCM_TSTAMP_ACK; + state = "TX ACK"; + break; + case J1939_ERRQUEUE_TX_SCHED: + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_info = SCM_TSTAMP_SCHED; + state = "TX SCH"; + break; + case J1939_ERRQUEUE_TX_ABORT: + serr->ee.ee_errno = session->err; + serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; + serr->ee.ee_info = J1939_EE_INFO_TX_ABORT; + state = "TX ABT"; + break; + case J1939_ERRQUEUE_RX_RTS: + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; + serr->ee.ee_info = J1939_EE_INFO_RX_RTS; + state = "RX RTS"; + break; + case J1939_ERRQUEUE_RX_DPO: + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; + serr->ee.ee_info = J1939_EE_INFO_RX_DPO; + state = "RX DPO"; + break; + case J1939_ERRQUEUE_RX_ABORT: + serr->ee.ee_errno = session->err; + serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; + serr->ee.ee_info = J1939_EE_INFO_RX_ABORT; + state = "RX ABT"; + break; + } + + serr->opt_stats = true; + if (tsflags & SOF_TIMESTAMPING_OPT_ID) + serr->ee.ee_data = session->tskey; + + netdev_dbg(session->priv->ndev, "%s: 0x%p tskey: %i, state: %s\n", + __func__, session, session->tskey, state); + err = sock_queue_err_skb(sk, skb); + + if (err) + kfree_skb(skb); +}; + +void j1939_sk_errqueue(struct j1939_session *session, + enum j1939_sk_errqueue_type type) +{ + struct j1939_priv *priv = session->priv; + struct j1939_sock *jsk; + + if (session->sk) { + /* send TX notifications to the socket of origin */ + __j1939_sk_errqueue(session, session->sk, type); + return; + } + + /* spread RX notifications to all sockets subscribed to this session */ + spin_lock_bh(&priv->j1939_socks_lock); + list_for_each_entry(jsk, &priv->j1939_socks, list) { + if (j1939_sk_recv_match_one(jsk, &session->skcb)) + __j1939_sk_errqueue(session, &jsk->sk, type); + } + spin_unlock_bh(&priv->j1939_socks_lock); +}; + +void j1939_sk_send_loop_abort(struct sock *sk, int err) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + if (jsk->state & J1939_SOCK_ERRQUEUE) + return; + + sk->sk_err = err; + + sk_error_report(sk); +} + +static int j1939_sk_send_loop(struct j1939_priv *priv, struct sock *sk, + struct msghdr *msg, size_t size) + +{ + struct j1939_sock *jsk = j1939_sk(sk); + struct j1939_session *session = j1939_sk_get_incomplete_session(jsk); + struct sk_buff *skb; + size_t segment_size, todo_size; + int ret = 0; + + if (session && + session->total_message_size != session->total_queued_size + size) { + j1939_session_put(session); + return -EIO; + } + + todo_size = size; + + while (todo_size) { + struct j1939_sk_buff_cb *skcb; + + segment_size = min_t(size_t, J1939_MAX_TP_PACKET_SIZE, + todo_size); + + /* Allocate skb for one segment */ + skb = j1939_sk_alloc_skb(priv->ndev, sk, msg, segment_size, + &ret); + if (ret) + break; + + skcb = j1939_skb_to_cb(skb); + + if (!session) { + /* at this point the size should be full size + * of the session + */ + skcb->offset = 0; + session = j1939_tp_send(priv, skb, size); + if (IS_ERR(session)) { + ret = PTR_ERR(session); + goto kfree_skb; + } + if (j1939_sk_queue_session(session)) { + /* try to activate session if we a + * fist in the queue + */ + if (!j1939_session_activate(session)) { + j1939_tp_schedule_txtimer(session, 0); + } else { + ret = -EBUSY; + session->err = ret; + j1939_sk_queue_drop_all(priv, jsk, + EBUSY); + break; + } + } + } else { + skcb->offset = session->total_queued_size; + j1939_session_skb_queue(session, skb); + } + + todo_size -= segment_size; + session->total_queued_size += segment_size; + } + + switch (ret) { + case 0: /* OK */ + if (todo_size) + netdev_warn(priv->ndev, + "no error found and not completely queued?! %zu\n", + todo_size); + ret = size; + break; + case -ERESTARTSYS: + ret = -EINTR; + fallthrough; + case -EAGAIN: /* OK */ + if (todo_size != size) + ret = size - todo_size; + break; + default: /* ERROR */ + break; + } + + if (session) + j1939_session_put(session); + + return ret; + + kfree_skb: + kfree_skb(skb); + return ret; +} + +static int j1939_sk_sendmsg(struct socket *sock, struct msghdr *msg, + size_t size) +{ + struct sock *sk = sock->sk; + struct j1939_sock *jsk = j1939_sk(sk); + struct j1939_priv *priv; + int ifindex; + int ret; + + lock_sock(sock->sk); + /* various socket state tests */ + if (!(jsk->state & J1939_SOCK_BOUND)) { + ret = -EBADFD; + goto sendmsg_done; + } + + priv = jsk->priv; + ifindex = jsk->ifindex; + + if (!jsk->addr.src_name && jsk->addr.sa == J1939_NO_ADDR) { + /* no source address assigned yet */ + ret = -EBADFD; + goto sendmsg_done; + } + + /* deal with provided destination address info */ + if (msg->msg_name) { + struct sockaddr_can *addr = msg->msg_name; + + if (msg->msg_namelen < J1939_MIN_NAMELEN) { + ret = -EINVAL; + goto sendmsg_done; + } + + if (addr->can_family != AF_CAN) { + ret = -EINVAL; + goto sendmsg_done; + } + + if (addr->can_ifindex && addr->can_ifindex != ifindex) { + ret = -EBADFD; + goto sendmsg_done; + } + + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) && + !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) { + ret = -EINVAL; + goto sendmsg_done; + } + + if (!addr->can_addr.j1939.name && + addr->can_addr.j1939.addr == J1939_NO_ADDR && + !sock_flag(sk, SOCK_BROADCAST)) { + /* broadcast, but SO_BROADCAST not set */ + ret = -EACCES; + goto sendmsg_done; + } + } else { + if (!jsk->addr.dst_name && jsk->addr.da == J1939_NO_ADDR && + !sock_flag(sk, SOCK_BROADCAST)) { + /* broadcast, but SO_BROADCAST not set */ + ret = -EACCES; + goto sendmsg_done; + } + } + + ret = j1939_sk_send_loop(priv, sk, msg, size); + +sendmsg_done: + release_sock(sock->sk); + + return ret; +} + +void j1939_sk_netdev_event_netdown(struct j1939_priv *priv) +{ + struct j1939_sock *jsk; + int error_code = ENETDOWN; + + spin_lock_bh(&priv->j1939_socks_lock); + list_for_each_entry(jsk, &priv->j1939_socks, list) { + jsk->sk.sk_err = error_code; + if (!sock_flag(&jsk->sk, SOCK_DEAD)) + sk_error_report(&jsk->sk); + + j1939_sk_queue_drop_all(priv, jsk, error_code); + } + spin_unlock_bh(&priv->j1939_socks_lock); +} + +static int j1939_sk_no_ioctlcmd(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + /* no ioctls for socket layer -> hand it down to NIC layer */ + return -ENOIOCTLCMD; +} + +static const struct proto_ops j1939_ops = { + .family = PF_CAN, + .release = j1939_sk_release, + .bind = j1939_sk_bind, + .connect = j1939_sk_connect, + .socketpair = sock_no_socketpair, + .accept = sock_no_accept, + .getname = j1939_sk_getname, + .poll = datagram_poll, + .ioctl = j1939_sk_no_ioctlcmd, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .setsockopt = j1939_sk_setsockopt, + .getsockopt = j1939_sk_getsockopt, + .sendmsg = j1939_sk_sendmsg, + .recvmsg = j1939_sk_recvmsg, + .mmap = sock_no_mmap, +}; + +static struct proto j1939_proto __read_mostly = { + .name = "CAN_J1939", + .owner = THIS_MODULE, + .obj_size = sizeof(struct j1939_sock), + .init = j1939_sk_init, +}; + +const struct can_proto j1939_can_proto = { + .type = SOCK_DGRAM, + .protocol = CAN_J1939, + .ops = &j1939_ops, + .prot = &j1939_proto, +}; diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c new file mode 100644 index 000000000..fe3df23a2 --- /dev/null +++ b/net/can/j1939/transport.c @@ -0,0 +1,2206 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2018 Protonic, +// Robin van der Gracht <robin@protonic.nl> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +#include <linux/can/skb.h> + +#include "j1939-priv.h" + +#define J1939_XTP_TX_RETRY_LIMIT 100 + +#define J1939_ETP_PGN_CTL 0xc800 +#define J1939_ETP_PGN_DAT 0xc700 +#define J1939_TP_PGN_CTL 0xec00 +#define J1939_TP_PGN_DAT 0xeb00 + +#define J1939_TP_CMD_RTS 0x10 +#define J1939_TP_CMD_CTS 0x11 +#define J1939_TP_CMD_EOMA 0x13 +#define J1939_TP_CMD_BAM 0x20 +#define J1939_TP_CMD_ABORT 0xff + +#define J1939_ETP_CMD_RTS 0x14 +#define J1939_ETP_CMD_CTS 0x15 +#define J1939_ETP_CMD_DPO 0x16 +#define J1939_ETP_CMD_EOMA 0x17 +#define J1939_ETP_CMD_ABORT 0xff + +enum j1939_xtp_abort { + J1939_XTP_NO_ABORT = 0, + J1939_XTP_ABORT_BUSY = 1, + /* Already in one or more connection managed sessions and + * cannot support another. + * + * EALREADY: + * Operation already in progress + */ + + J1939_XTP_ABORT_RESOURCE = 2, + /* System resources were needed for another task so this + * connection managed session was terminated. + * + * EMSGSIZE: + * The socket type requires that message be sent atomically, + * and the size of the message to be sent made this + * impossible. + */ + + J1939_XTP_ABORT_TIMEOUT = 3, + /* A timeout occurred and this is the connection abort to + * close the session. + * + * EHOSTUNREACH: + * The destination host cannot be reached (probably because + * the host is down or a remote router cannot reach it). + */ + + J1939_XTP_ABORT_GENERIC = 4, + /* CTS messages received when data transfer is in progress + * + * EBADMSG: + * Not a data message + */ + + J1939_XTP_ABORT_FAULT = 5, + /* Maximal retransmit request limit reached + * + * ENOTRECOVERABLE: + * State not recoverable + */ + + J1939_XTP_ABORT_UNEXPECTED_DATA = 6, + /* Unexpected data transfer packet + * + * ENOTCONN: + * Transport endpoint is not connected + */ + + J1939_XTP_ABORT_BAD_SEQ = 7, + /* Bad sequence number (and software is not able to recover) + * + * EILSEQ: + * Illegal byte sequence + */ + + J1939_XTP_ABORT_DUP_SEQ = 8, + /* Duplicate sequence number (and software is not able to + * recover) + */ + + J1939_XTP_ABORT_EDPO_UNEXPECTED = 9, + /* Unexpected EDPO packet (ETP) or Message size > 1785 bytes + * (TP) + */ + + J1939_XTP_ABORT_BAD_EDPO_PGN = 10, + /* Unexpected EDPO PGN (PGN in EDPO is bad) */ + + J1939_XTP_ABORT_EDPO_OUTOF_CTS = 11, + /* EDPO number of packets is greater than CTS */ + + J1939_XTP_ABORT_BAD_EDPO_OFFSET = 12, + /* Bad EDPO offset */ + + J1939_XTP_ABORT_OTHER_DEPRECATED = 13, + /* Deprecated. Use 250 instead (Any other reason) */ + + J1939_XTP_ABORT_ECTS_UNXPECTED_PGN = 14, + /* Unexpected ECTS PGN (PGN in ECTS is bad) */ + + J1939_XTP_ABORT_ECTS_TOO_BIG = 15, + /* ECTS requested packets exceeds message size */ + + J1939_XTP_ABORT_OTHER = 250, + /* Any other reason (if a Connection Abort reason is + * identified that is not listed in the table use code 250) + */ +}; + +static unsigned int j1939_tp_block = 255; +static unsigned int j1939_tp_packet_delay; +static unsigned int j1939_tp_padding = 1; + +/* helpers */ +static const char *j1939_xtp_abort_to_str(enum j1939_xtp_abort abort) +{ + switch (abort) { + case J1939_XTP_ABORT_BUSY: + return "Already in one or more connection managed sessions and cannot support another."; + case J1939_XTP_ABORT_RESOURCE: + return "System resources were needed for another task so this connection managed session was terminated."; + case J1939_XTP_ABORT_TIMEOUT: + return "A timeout occurred and this is the connection abort to close the session."; + case J1939_XTP_ABORT_GENERIC: + return "CTS messages received when data transfer is in progress"; + case J1939_XTP_ABORT_FAULT: + return "Maximal retransmit request limit reached"; + case J1939_XTP_ABORT_UNEXPECTED_DATA: + return "Unexpected data transfer packet"; + case J1939_XTP_ABORT_BAD_SEQ: + return "Bad sequence number (and software is not able to recover)"; + case J1939_XTP_ABORT_DUP_SEQ: + return "Duplicate sequence number (and software is not able to recover)"; + case J1939_XTP_ABORT_EDPO_UNEXPECTED: + return "Unexpected EDPO packet (ETP) or Message size > 1785 bytes (TP)"; + case J1939_XTP_ABORT_BAD_EDPO_PGN: + return "Unexpected EDPO PGN (PGN in EDPO is bad)"; + case J1939_XTP_ABORT_EDPO_OUTOF_CTS: + return "EDPO number of packets is greater than CTS"; + case J1939_XTP_ABORT_BAD_EDPO_OFFSET: + return "Bad EDPO offset"; + case J1939_XTP_ABORT_OTHER_DEPRECATED: + return "Deprecated. Use 250 instead (Any other reason)"; + case J1939_XTP_ABORT_ECTS_UNXPECTED_PGN: + return "Unexpected ECTS PGN (PGN in ECTS is bad)"; + case J1939_XTP_ABORT_ECTS_TOO_BIG: + return "ECTS requested packets exceeds message size"; + case J1939_XTP_ABORT_OTHER: + return "Any other reason (if a Connection Abort reason is identified that is not listed in the table use code 250)"; + default: + return "<unknown>"; + } +} + +static int j1939_xtp_abort_to_errno(struct j1939_priv *priv, + enum j1939_xtp_abort abort) +{ + int err; + + switch (abort) { + case J1939_XTP_NO_ABORT: + WARN_ON_ONCE(abort == J1939_XTP_NO_ABORT); + err = 0; + break; + case J1939_XTP_ABORT_BUSY: + err = EALREADY; + break; + case J1939_XTP_ABORT_RESOURCE: + err = EMSGSIZE; + break; + case J1939_XTP_ABORT_TIMEOUT: + err = EHOSTUNREACH; + break; + case J1939_XTP_ABORT_GENERIC: + err = EBADMSG; + break; + case J1939_XTP_ABORT_FAULT: + err = ENOTRECOVERABLE; + break; + case J1939_XTP_ABORT_UNEXPECTED_DATA: + err = ENOTCONN; + break; + case J1939_XTP_ABORT_BAD_SEQ: + err = EILSEQ; + break; + case J1939_XTP_ABORT_DUP_SEQ: + err = EPROTO; + break; + case J1939_XTP_ABORT_EDPO_UNEXPECTED: + err = EPROTO; + break; + case J1939_XTP_ABORT_BAD_EDPO_PGN: + err = EPROTO; + break; + case J1939_XTP_ABORT_EDPO_OUTOF_CTS: + err = EPROTO; + break; + case J1939_XTP_ABORT_BAD_EDPO_OFFSET: + err = EPROTO; + break; + case J1939_XTP_ABORT_OTHER_DEPRECATED: + err = EPROTO; + break; + case J1939_XTP_ABORT_ECTS_UNXPECTED_PGN: + err = EPROTO; + break; + case J1939_XTP_ABORT_ECTS_TOO_BIG: + err = EPROTO; + break; + case J1939_XTP_ABORT_OTHER: + err = EPROTO; + break; + default: + netdev_warn(priv->ndev, "Unknown abort code %i", abort); + err = EPROTO; + } + + return err; +} + +static inline void j1939_session_list_lock(struct j1939_priv *priv) +{ + spin_lock_bh(&priv->active_session_list_lock); +} + +static inline void j1939_session_list_unlock(struct j1939_priv *priv) +{ + spin_unlock_bh(&priv->active_session_list_lock); +} + +void j1939_session_get(struct j1939_session *session) +{ + kref_get(&session->kref); +} + +/* session completion functions */ +static void __j1939_session_drop(struct j1939_session *session) +{ + if (!session->transmission) + return; + + j1939_sock_pending_del(session->sk); + sock_put(session->sk); +} + +static void j1939_session_destroy(struct j1939_session *session) +{ + struct sk_buff *skb; + + if (session->transmission) { + if (session->err) + j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_ABORT); + else + j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_ACK); + } else if (session->err) { + j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); + } + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + WARN_ON_ONCE(!list_empty(&session->sk_session_queue_entry)); + WARN_ON_ONCE(!list_empty(&session->active_session_list_entry)); + + while ((skb = skb_dequeue(&session->skb_queue)) != NULL) { + /* drop ref taken in j1939_session_skb_queue() */ + skb_unref(skb); + kfree_skb(skb); + } + __j1939_session_drop(session); + j1939_priv_put(session->priv); + kfree(session); +} + +static void __j1939_session_release(struct kref *kref) +{ + struct j1939_session *session = container_of(kref, struct j1939_session, + kref); + + j1939_session_destroy(session); +} + +void j1939_session_put(struct j1939_session *session) +{ + kref_put(&session->kref, __j1939_session_release); +} + +static void j1939_session_txtimer_cancel(struct j1939_session *session) +{ + if (hrtimer_cancel(&session->txtimer)) + j1939_session_put(session); +} + +static void j1939_session_rxtimer_cancel(struct j1939_session *session) +{ + if (hrtimer_cancel(&session->rxtimer)) + j1939_session_put(session); +} + +void j1939_session_timers_cancel(struct j1939_session *session) +{ + j1939_session_txtimer_cancel(session); + j1939_session_rxtimer_cancel(session); +} + +static inline bool j1939_cb_is_broadcast(const struct j1939_sk_buff_cb *skcb) +{ + return (!skcb->addr.dst_name && (skcb->addr.da == 0xff)); +} + +static void j1939_session_skb_drop_old(struct j1939_session *session) +{ + struct sk_buff *do_skb; + struct j1939_sk_buff_cb *do_skcb; + unsigned int offset_start; + unsigned long flags; + + if (skb_queue_len(&session->skb_queue) < 2) + return; + + offset_start = session->pkt.tx_acked * 7; + + spin_lock_irqsave(&session->skb_queue.lock, flags); + do_skb = skb_peek(&session->skb_queue); + do_skcb = j1939_skb_to_cb(do_skb); + + if ((do_skcb->offset + do_skb->len) < offset_start) { + __skb_unlink(do_skb, &session->skb_queue); + /* drop ref taken in j1939_session_skb_queue() */ + skb_unref(do_skb); + spin_unlock_irqrestore(&session->skb_queue.lock, flags); + + kfree_skb(do_skb); + } else { + spin_unlock_irqrestore(&session->skb_queue.lock, flags); + } +} + +void j1939_session_skb_queue(struct j1939_session *session, + struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_priv *priv = session->priv; + + j1939_ac_fixup(priv, skb); + + if (j1939_address_is_unicast(skcb->addr.da) && + priv->ents[skcb->addr.da].nusers) + skcb->flags |= J1939_ECU_LOCAL_DST; + + skcb->flags |= J1939_ECU_LOCAL_SRC; + + skb_get(skb); + skb_queue_tail(&session->skb_queue, skb); +} + +static struct +sk_buff *j1939_session_skb_get_by_offset(struct j1939_session *session, + unsigned int offset_start) +{ + struct j1939_priv *priv = session->priv; + struct j1939_sk_buff_cb *do_skcb; + struct sk_buff *skb = NULL; + struct sk_buff *do_skb; + unsigned long flags; + + spin_lock_irqsave(&session->skb_queue.lock, flags); + skb_queue_walk(&session->skb_queue, do_skb) { + do_skcb = j1939_skb_to_cb(do_skb); + + if (offset_start >= do_skcb->offset && + offset_start < (do_skcb->offset + do_skb->len)) { + skb = do_skb; + } + } + + if (skb) + skb_get(skb); + + spin_unlock_irqrestore(&session->skb_queue.lock, flags); + + if (!skb) + netdev_dbg(priv->ndev, "%s: 0x%p: no skb found for start: %i, queue size: %i\n", + __func__, session, offset_start, + skb_queue_len(&session->skb_queue)); + + return skb; +} + +static struct sk_buff *j1939_session_skb_get(struct j1939_session *session) +{ + unsigned int offset_start; + + offset_start = session->pkt.dpo * 7; + return j1939_session_skb_get_by_offset(session, offset_start); +} + +/* see if we are receiver + * returns 0 for broadcasts, although we will receive them + */ +static inline int j1939_tp_im_receiver(const struct j1939_sk_buff_cb *skcb) +{ + return skcb->flags & J1939_ECU_LOCAL_DST; +} + +/* see if we are sender */ +static inline int j1939_tp_im_transmitter(const struct j1939_sk_buff_cb *skcb) +{ + return skcb->flags & J1939_ECU_LOCAL_SRC; +} + +/* see if we are involved as either receiver or transmitter */ +static int j1939_tp_im_involved(const struct j1939_sk_buff_cb *skcb, bool swap) +{ + if (swap) + return j1939_tp_im_receiver(skcb); + else + return j1939_tp_im_transmitter(skcb); +} + +static int j1939_tp_im_involved_anydir(struct j1939_sk_buff_cb *skcb) +{ + return skcb->flags & (J1939_ECU_LOCAL_SRC | J1939_ECU_LOCAL_DST); +} + +/* extract pgn from flow-ctl message */ +static inline pgn_t j1939_xtp_ctl_to_pgn(const u8 *dat) +{ + pgn_t pgn; + + pgn = (dat[7] << 16) | (dat[6] << 8) | (dat[5] << 0); + if (j1939_pgn_is_pdu1(pgn)) + pgn &= 0xffff00; + return pgn; +} + +static inline unsigned int j1939_tp_ctl_to_size(const u8 *dat) +{ + return (dat[2] << 8) + (dat[1] << 0); +} + +static inline unsigned int j1939_etp_ctl_to_packet(const u8 *dat) +{ + return (dat[4] << 16) | (dat[3] << 8) | (dat[2] << 0); +} + +static inline unsigned int j1939_etp_ctl_to_size(const u8 *dat) +{ + return (dat[4] << 24) | (dat[3] << 16) | + (dat[2] << 8) | (dat[1] << 0); +} + +/* find existing session: + * reverse: swap cb's src & dst + * there is no problem with matching broadcasts, since + * broadcasts (no dst, no da) would never call this + * with reverse == true + */ +static bool j1939_session_match(struct j1939_addr *se_addr, + struct j1939_addr *sk_addr, bool reverse) +{ + if (se_addr->type != sk_addr->type) + return false; + + if (reverse) { + if (se_addr->src_name) { + if (se_addr->src_name != sk_addr->dst_name) + return false; + } else if (se_addr->sa != sk_addr->da) { + return false; + } + + if (se_addr->dst_name) { + if (se_addr->dst_name != sk_addr->src_name) + return false; + } else if (se_addr->da != sk_addr->sa) { + return false; + } + } else { + if (se_addr->src_name) { + if (se_addr->src_name != sk_addr->src_name) + return false; + } else if (se_addr->sa != sk_addr->sa) { + return false; + } + + if (se_addr->dst_name) { + if (se_addr->dst_name != sk_addr->dst_name) + return false; + } else if (se_addr->da != sk_addr->da) { + return false; + } + } + + return true; +} + +static struct +j1939_session *j1939_session_get_by_addr_locked(struct j1939_priv *priv, + struct list_head *root, + struct j1939_addr *addr, + bool reverse, bool transmitter) +{ + struct j1939_session *session; + + lockdep_assert_held(&priv->active_session_list_lock); + + list_for_each_entry(session, root, active_session_list_entry) { + j1939_session_get(session); + if (j1939_session_match(&session->skcb.addr, addr, reverse) && + session->transmission == transmitter) + return session; + j1939_session_put(session); + } + + return NULL; +} + +static struct +j1939_session *j1939_session_get_simple(struct j1939_priv *priv, + struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + + lockdep_assert_held(&priv->active_session_list_lock); + + list_for_each_entry(session, &priv->active_session_list, + active_session_list_entry) { + j1939_session_get(session); + if (session->skcb.addr.type == J1939_SIMPLE && + session->tskey == skcb->tskey && session->sk == skb->sk) + return session; + j1939_session_put(session); + } + + return NULL; +} + +static struct +j1939_session *j1939_session_get_by_addr(struct j1939_priv *priv, + struct j1939_addr *addr, + bool reverse, bool transmitter) +{ + struct j1939_session *session; + + j1939_session_list_lock(priv); + session = j1939_session_get_by_addr_locked(priv, + &priv->active_session_list, + addr, reverse, transmitter); + j1939_session_list_unlock(priv); + + return session; +} + +static void j1939_skbcb_swap(struct j1939_sk_buff_cb *skcb) +{ + u8 tmp = 0; + + swap(skcb->addr.dst_name, skcb->addr.src_name); + swap(skcb->addr.da, skcb->addr.sa); + + /* swap SRC and DST flags, leave other untouched */ + if (skcb->flags & J1939_ECU_LOCAL_SRC) + tmp |= J1939_ECU_LOCAL_DST; + if (skcb->flags & J1939_ECU_LOCAL_DST) + tmp |= J1939_ECU_LOCAL_SRC; + skcb->flags &= ~(J1939_ECU_LOCAL_SRC | J1939_ECU_LOCAL_DST); + skcb->flags |= tmp; +} + +static struct +sk_buff *j1939_tp_tx_dat_new(struct j1939_priv *priv, + const struct j1939_sk_buff_cb *re_skcb, + bool ctl, + bool swap_src_dst) +{ + struct sk_buff *skb; + struct j1939_sk_buff_cb *skcb; + + skb = alloc_skb(sizeof(struct can_frame) + sizeof(struct can_skb_priv), + GFP_ATOMIC); + if (unlikely(!skb)) + return ERR_PTR(-ENOMEM); + + skb->dev = priv->ndev; + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = priv->ndev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + /* reserve CAN header */ + skb_reserve(skb, offsetof(struct can_frame, data)); + + /* skb->cb must be large enough to hold a j1939_sk_buff_cb structure */ + BUILD_BUG_ON(sizeof(skb->cb) < sizeof(*re_skcb)); + + memcpy(skb->cb, re_skcb, sizeof(*re_skcb)); + skcb = j1939_skb_to_cb(skb); + if (swap_src_dst) + j1939_skbcb_swap(skcb); + + if (ctl) { + if (skcb->addr.type == J1939_ETP) + skcb->addr.pgn = J1939_ETP_PGN_CTL; + else + skcb->addr.pgn = J1939_TP_PGN_CTL; + } else { + if (skcb->addr.type == J1939_ETP) + skcb->addr.pgn = J1939_ETP_PGN_DAT; + else + skcb->addr.pgn = J1939_TP_PGN_DAT; + } + + return skb; +} + +/* TP transmit packet functions */ +static int j1939_tp_tx_dat(struct j1939_session *session, + const u8 *dat, int len) +{ + struct j1939_priv *priv = session->priv; + struct sk_buff *skb; + + skb = j1939_tp_tx_dat_new(priv, &session->skcb, + false, false); + if (IS_ERR(skb)) + return PTR_ERR(skb); + + skb_put_data(skb, dat, len); + if (j1939_tp_padding && len < 8) + memset(skb_put(skb, 8 - len), 0xff, 8 - len); + + return j1939_send_one(priv, skb); +} + +static int j1939_xtp_do_tx_ctl(struct j1939_priv *priv, + const struct j1939_sk_buff_cb *re_skcb, + bool swap_src_dst, pgn_t pgn, const u8 *dat) +{ + struct sk_buff *skb; + u8 *skdat; + + if (!j1939_tp_im_involved(re_skcb, swap_src_dst)) + return 0; + + skb = j1939_tp_tx_dat_new(priv, re_skcb, true, swap_src_dst); + if (IS_ERR(skb)) + return PTR_ERR(skb); + + skdat = skb_put(skb, 8); + memcpy(skdat, dat, 5); + skdat[5] = (pgn >> 0); + skdat[6] = (pgn >> 8); + skdat[7] = (pgn >> 16); + + return j1939_send_one(priv, skb); +} + +static inline int j1939_tp_tx_ctl(struct j1939_session *session, + bool swap_src_dst, const u8 *dat) +{ + struct j1939_priv *priv = session->priv; + + return j1939_xtp_do_tx_ctl(priv, &session->skcb, + swap_src_dst, + session->skcb.addr.pgn, dat); +} + +static int j1939_xtp_tx_abort(struct j1939_priv *priv, + const struct j1939_sk_buff_cb *re_skcb, + bool swap_src_dst, + enum j1939_xtp_abort err, + pgn_t pgn) +{ + u8 dat[5]; + + if (!j1939_tp_im_involved(re_skcb, swap_src_dst)) + return 0; + + memset(dat, 0xff, sizeof(dat)); + dat[0] = J1939_TP_CMD_ABORT; + dat[1] = err; + return j1939_xtp_do_tx_ctl(priv, re_skcb, swap_src_dst, pgn, dat); +} + +void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec) +{ + j1939_session_get(session); + hrtimer_start(&session->txtimer, ms_to_ktime(msec), + HRTIMER_MODE_REL_SOFT); +} + +static inline void j1939_tp_set_rxtimeout(struct j1939_session *session, + int msec) +{ + j1939_session_rxtimer_cancel(session); + j1939_session_get(session); + hrtimer_start(&session->rxtimer, ms_to_ktime(msec), + HRTIMER_MODE_REL_SOFT); +} + +static int j1939_session_tx_rts(struct j1939_session *session) +{ + u8 dat[8]; + int ret; + + memset(dat, 0xff, sizeof(dat)); + + dat[1] = (session->total_message_size >> 0); + dat[2] = (session->total_message_size >> 8); + dat[3] = session->pkt.total; + + if (session->skcb.addr.type == J1939_ETP) { + dat[0] = J1939_ETP_CMD_RTS; + dat[1] = (session->total_message_size >> 0); + dat[2] = (session->total_message_size >> 8); + dat[3] = (session->total_message_size >> 16); + dat[4] = (session->total_message_size >> 24); + } else if (j1939_cb_is_broadcast(&session->skcb)) { + dat[0] = J1939_TP_CMD_BAM; + /* fake cts for broadcast */ + session->pkt.tx = 0; + } else { + dat[0] = J1939_TP_CMD_RTS; + dat[4] = dat[3]; + } + + if (dat[0] == session->last_txcmd) + /* done already */ + return 0; + + ret = j1939_tp_tx_ctl(session, false, dat); + if (ret < 0) + return ret; + + session->last_txcmd = dat[0]; + if (dat[0] == J1939_TP_CMD_BAM) { + j1939_tp_schedule_txtimer(session, 50); + j1939_tp_set_rxtimeout(session, 250); + } else { + j1939_tp_set_rxtimeout(session, 1250); + } + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static int j1939_session_tx_dpo(struct j1939_session *session) +{ + unsigned int pkt; + u8 dat[8]; + int ret; + + memset(dat, 0xff, sizeof(dat)); + + dat[0] = J1939_ETP_CMD_DPO; + session->pkt.dpo = session->pkt.tx_acked; + pkt = session->pkt.dpo; + dat[1] = session->pkt.last - session->pkt.tx_acked; + dat[2] = (pkt >> 0); + dat[3] = (pkt >> 8); + dat[4] = (pkt >> 16); + + ret = j1939_tp_tx_ctl(session, false, dat); + if (ret < 0) + return ret; + + session->last_txcmd = dat[0]; + j1939_tp_set_rxtimeout(session, 1250); + session->pkt.tx = session->pkt.tx_acked; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static int j1939_session_tx_dat(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + struct j1939_sk_buff_cb *se_skcb; + int offset, pkt_done, pkt_end; + unsigned int len, pdelay; + struct sk_buff *se_skb; + const u8 *tpdat; + int ret = 0; + u8 dat[8]; + + se_skb = j1939_session_skb_get_by_offset(session, session->pkt.tx * 7); + if (!se_skb) + return -ENOBUFS; + + se_skcb = j1939_skb_to_cb(se_skb); + tpdat = se_skb->data; + ret = 0; + pkt_done = 0; + if (session->skcb.addr.type != J1939_ETP && + j1939_cb_is_broadcast(&session->skcb)) + pkt_end = session->pkt.total; + else + pkt_end = session->pkt.last; + + while (session->pkt.tx < pkt_end) { + dat[0] = session->pkt.tx - session->pkt.dpo + 1; + offset = (session->pkt.tx * 7) - se_skcb->offset; + len = se_skb->len - offset; + if (len > 7) + len = 7; + + if (offset + len > se_skb->len) { + netdev_err_once(priv->ndev, + "%s: 0x%p: requested data outside of queued buffer: offset %i, len %i, pkt.tx: %i\n", + __func__, session, se_skcb->offset, + se_skb->len , session->pkt.tx); + ret = -EOVERFLOW; + goto out_free; + } + + if (!len) { + ret = -ENOBUFS; + break; + } + + memcpy(&dat[1], &tpdat[offset], len); + ret = j1939_tp_tx_dat(session, dat, len + 1); + if (ret < 0) { + /* ENOBUFS == CAN interface TX queue is full */ + if (ret != -ENOBUFS) + netdev_alert(priv->ndev, + "%s: 0x%p: queue data error: %i\n", + __func__, session, ret); + break; + } + + session->last_txcmd = 0xff; + pkt_done++; + session->pkt.tx++; + pdelay = j1939_cb_is_broadcast(&session->skcb) ? 50 : + j1939_tp_packet_delay; + + if (session->pkt.tx < session->pkt.total && pdelay) { + j1939_tp_schedule_txtimer(session, pdelay); + break; + } + } + + if (pkt_done) + j1939_tp_set_rxtimeout(session, 250); + + out_free: + if (ret) + kfree_skb(se_skb); + else + consume_skb(se_skb); + + return ret; +} + +static int j1939_xtp_txnext_transmiter(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + int ret = 0; + + if (!j1939_tp_im_transmitter(&session->skcb)) { + netdev_alert(priv->ndev, "%s: 0x%p: called by not transmitter!\n", + __func__, session); + return -EINVAL; + } + + switch (session->last_cmd) { + case 0: + ret = j1939_session_tx_rts(session); + break; + + case J1939_ETP_CMD_CTS: + if (session->last_txcmd != J1939_ETP_CMD_DPO) { + ret = j1939_session_tx_dpo(session); + if (ret) + return ret; + } + + fallthrough; + case J1939_TP_CMD_CTS: + case 0xff: /* did some data */ + case J1939_ETP_CMD_DPO: + case J1939_TP_CMD_BAM: + ret = j1939_session_tx_dat(session); + + break; + default: + netdev_alert(priv->ndev, "%s: 0x%p: unexpected last_cmd: %x\n", + __func__, session, session->last_cmd); + } + + return ret; +} + +static int j1939_session_tx_cts(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + unsigned int pkt, len; + int ret; + u8 dat[8]; + + if (!j1939_sk_recv_match(priv, &session->skcb)) + return -ENOENT; + + len = session->pkt.total - session->pkt.rx; + len = min3(len, session->pkt.block, j1939_tp_block ?: 255); + memset(dat, 0xff, sizeof(dat)); + + if (session->skcb.addr.type == J1939_ETP) { + pkt = session->pkt.rx + 1; + dat[0] = J1939_ETP_CMD_CTS; + dat[1] = len; + dat[2] = (pkt >> 0); + dat[3] = (pkt >> 8); + dat[4] = (pkt >> 16); + } else { + dat[0] = J1939_TP_CMD_CTS; + dat[1] = len; + dat[2] = session->pkt.rx + 1; + } + + if (dat[0] == session->last_txcmd) + /* done already */ + return 0; + + ret = j1939_tp_tx_ctl(session, true, dat); + if (ret < 0) + return ret; + + if (len) + /* only mark cts done when len is set */ + session->last_txcmd = dat[0]; + j1939_tp_set_rxtimeout(session, 1250); + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static int j1939_session_tx_eoma(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + u8 dat[8]; + int ret; + + if (!j1939_sk_recv_match(priv, &session->skcb)) + return -ENOENT; + + memset(dat, 0xff, sizeof(dat)); + + if (session->skcb.addr.type == J1939_ETP) { + dat[0] = J1939_ETP_CMD_EOMA; + dat[1] = session->total_message_size >> 0; + dat[2] = session->total_message_size >> 8; + dat[3] = session->total_message_size >> 16; + dat[4] = session->total_message_size >> 24; + } else { + dat[0] = J1939_TP_CMD_EOMA; + dat[1] = session->total_message_size; + dat[2] = session->total_message_size >> 8; + dat[3] = session->pkt.total; + } + + if (dat[0] == session->last_txcmd) + /* done already */ + return 0; + + ret = j1939_tp_tx_ctl(session, true, dat); + if (ret < 0) + return ret; + + session->last_txcmd = dat[0]; + + /* wait for the EOMA packet to come in */ + j1939_tp_set_rxtimeout(session, 1250); + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static int j1939_xtp_txnext_receiver(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + int ret = 0; + + if (!j1939_tp_im_receiver(&session->skcb)) { + netdev_alert(priv->ndev, "%s: 0x%p: called by not receiver!\n", + __func__, session); + return -EINVAL; + } + + switch (session->last_cmd) { + case J1939_TP_CMD_RTS: + case J1939_ETP_CMD_RTS: + ret = j1939_session_tx_cts(session); + break; + + case J1939_ETP_CMD_CTS: + case J1939_TP_CMD_CTS: + case 0xff: /* did some data */ + case J1939_ETP_CMD_DPO: + if ((session->skcb.addr.type == J1939_TP && + j1939_cb_is_broadcast(&session->skcb))) + break; + + if (session->pkt.rx >= session->pkt.total) { + ret = j1939_session_tx_eoma(session); + } else if (session->pkt.rx >= session->pkt.last) { + session->last_txcmd = 0; + ret = j1939_session_tx_cts(session); + } + break; + default: + netdev_alert(priv->ndev, "%s: 0x%p: unexpected last_cmd: %x\n", + __func__, session, session->last_cmd); + } + + return ret; +} + +static int j1939_simple_txnext(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + struct sk_buff *se_skb = j1939_session_skb_get(session); + struct sk_buff *skb; + int ret; + + if (!se_skb) + return 0; + + skb = skb_clone(se_skb, GFP_ATOMIC); + if (!skb) { + ret = -ENOMEM; + goto out_free; + } + + can_skb_set_owner(skb, se_skb->sk); + + j1939_tp_set_rxtimeout(session, J1939_SIMPLE_ECHO_TIMEOUT_MS); + + ret = j1939_send_one(priv, skb); + if (ret) + goto out_free; + + j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_SCHED); + j1939_sk_queue_activate_next(session); + + out_free: + if (ret) + kfree_skb(se_skb); + else + consume_skb(se_skb); + + return ret; +} + +static bool j1939_session_deactivate_locked(struct j1939_session *session) +{ + bool active = false; + + lockdep_assert_held(&session->priv->active_session_list_lock); + + if (session->state >= J1939_SESSION_ACTIVE && + session->state < J1939_SESSION_ACTIVE_MAX) { + active = true; + + list_del_init(&session->active_session_list_entry); + session->state = J1939_SESSION_DONE; + j1939_session_put(session); + } + + return active; +} + +static bool j1939_session_deactivate(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + bool active; + + j1939_session_list_lock(priv); + active = j1939_session_deactivate_locked(session); + j1939_session_list_unlock(priv); + + return active; +} + +static void +j1939_session_deactivate_activate_next(struct j1939_session *session) +{ + if (j1939_session_deactivate(session)) + j1939_sk_queue_activate_next(session); +} + +static void __j1939_session_cancel(struct j1939_session *session, + enum j1939_xtp_abort err) +{ + struct j1939_priv *priv = session->priv; + + WARN_ON_ONCE(!err); + lockdep_assert_held(&session->priv->active_session_list_lock); + + session->err = j1939_xtp_abort_to_errno(priv, err); + session->state = J1939_SESSION_WAITING_ABORT; + /* do not send aborts on incoming broadcasts */ + if (!j1939_cb_is_broadcast(&session->skcb)) { + j1939_xtp_tx_abort(priv, &session->skcb, + !session->transmission, + err, session->skcb.addr.pgn); + } + + if (session->sk) + j1939_sk_send_loop_abort(session->sk, session->err); +} + +static void j1939_session_cancel(struct j1939_session *session, + enum j1939_xtp_abort err) +{ + j1939_session_list_lock(session->priv); + + if (session->state >= J1939_SESSION_ACTIVE && + session->state < J1939_SESSION_WAITING_ABORT) { + j1939_tp_set_rxtimeout(session, J1939_XTP_ABORT_TIMEOUT_MS); + __j1939_session_cancel(session, err); + } + + j1939_session_list_unlock(session->priv); + + if (!session->sk) + j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); +} + +static enum hrtimer_restart j1939_tp_txtimer(struct hrtimer *hrtimer) +{ + struct j1939_session *session = + container_of(hrtimer, struct j1939_session, txtimer); + struct j1939_priv *priv = session->priv; + int ret = 0; + + if (session->skcb.addr.type == J1939_SIMPLE) { + ret = j1939_simple_txnext(session); + } else { + if (session->transmission) + ret = j1939_xtp_txnext_transmiter(session); + else + ret = j1939_xtp_txnext_receiver(session); + } + + switch (ret) { + case -ENOBUFS: + /* Retry limit is currently arbitrary chosen */ + if (session->tx_retry < J1939_XTP_TX_RETRY_LIMIT) { + session->tx_retry++; + j1939_tp_schedule_txtimer(session, + 10 + get_random_u32_below(16)); + } else { + netdev_alert(priv->ndev, "%s: 0x%p: tx retry count reached\n", + __func__, session); + session->err = -ENETUNREACH; + j1939_session_rxtimer_cancel(session); + j1939_session_deactivate_activate_next(session); + } + break; + case -ENETDOWN: + /* In this case we should get a netdev_event(), all active + * sessions will be cleared by + * j1939_cancel_all_active_sessions(). So handle this as an + * error, but let j1939_cancel_all_active_sessions() do the + * cleanup including propagation of the error to user space. + */ + break; + case -EOVERFLOW: + j1939_session_cancel(session, J1939_XTP_ABORT_ECTS_TOO_BIG); + break; + case 0: + session->tx_retry = 0; + break; + default: + netdev_alert(priv->ndev, "%s: 0x%p: tx aborted with unknown reason: %i\n", + __func__, session, ret); + if (session->skcb.addr.type != J1939_SIMPLE) { + j1939_session_cancel(session, J1939_XTP_ABORT_OTHER); + } else { + session->err = ret; + j1939_session_rxtimer_cancel(session); + j1939_session_deactivate_activate_next(session); + } + } + + j1939_session_put(session); + + return HRTIMER_NORESTART; +} + +static void j1939_session_completed(struct j1939_session *session) +{ + struct sk_buff *se_skb; + + if (!session->transmission) { + se_skb = j1939_session_skb_get(session); + /* distribute among j1939 receivers */ + j1939_sk_recv(session->priv, se_skb); + consume_skb(se_skb); + } + + j1939_session_deactivate_activate_next(session); +} + +static enum hrtimer_restart j1939_tp_rxtimer(struct hrtimer *hrtimer) +{ + struct j1939_session *session = container_of(hrtimer, + struct j1939_session, + rxtimer); + struct j1939_priv *priv = session->priv; + + if (session->state == J1939_SESSION_WAITING_ABORT) { + netdev_alert(priv->ndev, "%s: 0x%p: abort rx timeout. Force session deactivation\n", + __func__, session); + + j1939_session_deactivate_activate_next(session); + + } else if (session->skcb.addr.type == J1939_SIMPLE) { + netdev_alert(priv->ndev, "%s: 0x%p: Timeout. Failed to send simple message.\n", + __func__, session); + + /* The message is probably stuck in the CAN controller and can + * be send as soon as CAN bus is in working state again. + */ + session->err = -ETIME; + j1939_session_deactivate(session); + } else { + j1939_session_list_lock(session->priv); + if (session->state >= J1939_SESSION_ACTIVE && + session->state < J1939_SESSION_ACTIVE_MAX) { + netdev_alert(priv->ndev, "%s: 0x%p: rx timeout, send abort\n", + __func__, session); + j1939_session_get(session); + hrtimer_start(&session->rxtimer, + ms_to_ktime(J1939_XTP_ABORT_TIMEOUT_MS), + HRTIMER_MODE_REL_SOFT); + __j1939_session_cancel(session, J1939_XTP_ABORT_TIMEOUT); + } + j1939_session_list_unlock(session->priv); + + if (!session->sk) + j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); + } + + j1939_session_put(session); + + return HRTIMER_NORESTART; +} + +static bool j1939_xtp_rx_cmd_bad_pgn(struct j1939_session *session, + const struct sk_buff *skb) +{ + const struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + pgn_t pgn = j1939_xtp_ctl_to_pgn(skb->data); + struct j1939_priv *priv = session->priv; + enum j1939_xtp_abort abort = J1939_XTP_NO_ABORT; + u8 cmd = skb->data[0]; + + if (session->skcb.addr.pgn == pgn) + return false; + + switch (cmd) { + case J1939_TP_CMD_BAM: + abort = J1939_XTP_NO_ABORT; + break; + + case J1939_ETP_CMD_RTS: + fallthrough; + case J1939_TP_CMD_RTS: + abort = J1939_XTP_ABORT_BUSY; + break; + + case J1939_ETP_CMD_CTS: + fallthrough; + case J1939_TP_CMD_CTS: + abort = J1939_XTP_ABORT_ECTS_UNXPECTED_PGN; + break; + + case J1939_ETP_CMD_DPO: + abort = J1939_XTP_ABORT_BAD_EDPO_PGN; + break; + + case J1939_ETP_CMD_EOMA: + fallthrough; + case J1939_TP_CMD_EOMA: + abort = J1939_XTP_ABORT_OTHER; + break; + + case J1939_ETP_CMD_ABORT: /* && J1939_TP_CMD_ABORT */ + abort = J1939_XTP_NO_ABORT; + break; + + default: + WARN_ON_ONCE(1); + break; + } + + netdev_warn(priv->ndev, "%s: 0x%p: CMD 0x%02x with PGN 0x%05x for running session with different PGN 0x%05x.\n", + __func__, session, cmd, pgn, session->skcb.addr.pgn); + if (abort != J1939_XTP_NO_ABORT) + j1939_xtp_tx_abort(priv, skcb, true, abort, pgn); + + return true; +} + +static void j1939_xtp_rx_abort_one(struct j1939_priv *priv, struct sk_buff *skb, + bool reverse, bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + u8 abort = skb->data[1]; + + session = j1939_session_get_by_addr(priv, &skcb->addr, reverse, + transmitter); + if (!session) + return; + + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + goto abort_put; + + netdev_info(priv->ndev, "%s: 0x%p: 0x%05x: (%u) %s\n", __func__, + session, j1939_xtp_ctl_to_pgn(skb->data), abort, + j1939_xtp_abort_to_str(abort)); + + j1939_session_timers_cancel(session); + session->err = j1939_xtp_abort_to_errno(priv, abort); + if (session->sk) + j1939_sk_send_loop_abort(session->sk, session->err); + else + j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); + j1939_session_deactivate_activate_next(session); + +abort_put: + j1939_session_put(session); +} + +/* abort packets may come in 2 directions */ +static void +j1939_xtp_rx_abort(struct j1939_priv *priv, struct sk_buff *skb, + bool transmitter) +{ + j1939_xtp_rx_abort_one(priv, skb, false, transmitter); + j1939_xtp_rx_abort_one(priv, skb, true, transmitter); +} + +static void +j1939_xtp_rx_eoma_one(struct j1939_session *session, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + const u8 *dat; + int len; + + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + return; + + dat = skb->data; + + if (skcb->addr.type == J1939_ETP) + len = j1939_etp_ctl_to_size(dat); + else + len = j1939_tp_ctl_to_size(dat); + + if (session->total_message_size != len) { + netdev_warn_once(session->priv->ndev, + "%s: 0x%p: Incorrect size. Expected: %i; got: %i.\n", + __func__, session, session->total_message_size, + len); + } + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + session->pkt.tx_acked = session->pkt.total; + j1939_session_timers_cancel(session); + /* transmitted without problems */ + j1939_session_completed(session); +} + +static void +j1939_xtp_rx_eoma(struct j1939_priv *priv, struct sk_buff *skb, + bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + + session = j1939_session_get_by_addr(priv, &skcb->addr, true, + transmitter); + if (!session) + return; + + j1939_xtp_rx_eoma_one(session, skb); + j1939_session_put(session); +} + +static void +j1939_xtp_rx_cts_one(struct j1939_session *session, struct sk_buff *skb) +{ + enum j1939_xtp_abort err = J1939_XTP_ABORT_FAULT; + unsigned int pkt; + const u8 *dat; + + dat = skb->data; + + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + return; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + if (session->last_cmd == dat[0]) { + err = J1939_XTP_ABORT_DUP_SEQ; + goto out_session_cancel; + } + + if (session->skcb.addr.type == J1939_ETP) + pkt = j1939_etp_ctl_to_packet(dat); + else + pkt = dat[2]; + + if (!pkt) + goto out_session_cancel; + else if (dat[1] > session->pkt.block /* 0xff for etp */) + goto out_session_cancel; + + /* set packet counters only when not CTS(0) */ + session->pkt.tx_acked = pkt - 1; + j1939_session_skb_drop_old(session); + session->pkt.last = session->pkt.tx_acked + dat[1]; + if (session->pkt.last > session->pkt.total) + /* safety measure */ + session->pkt.last = session->pkt.total; + /* TODO: do not set tx here, do it in txtimer */ + session->pkt.tx = session->pkt.tx_acked; + + session->last_cmd = dat[0]; + if (dat[1]) { + j1939_tp_set_rxtimeout(session, 1250); + if (session->transmission) { + if (session->pkt.tx_acked) + j1939_sk_errqueue(session, + J1939_ERRQUEUE_TX_SCHED); + j1939_session_txtimer_cancel(session); + j1939_tp_schedule_txtimer(session, 0); + } + } else { + /* CTS(0) */ + j1939_tp_set_rxtimeout(session, 550); + } + return; + + out_session_cancel: + j1939_session_timers_cancel(session); + j1939_session_cancel(session, err); +} + +static void +j1939_xtp_rx_cts(struct j1939_priv *priv, struct sk_buff *skb, bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + + session = j1939_session_get_by_addr(priv, &skcb->addr, true, + transmitter); + if (!session) + return; + j1939_xtp_rx_cts_one(session, skb); + j1939_session_put(session); +} + +static struct j1939_session *j1939_session_new(struct j1939_priv *priv, + struct sk_buff *skb, size_t size) +{ + struct j1939_session *session; + struct j1939_sk_buff_cb *skcb; + + session = kzalloc(sizeof(*session), gfp_any()); + if (!session) + return NULL; + + INIT_LIST_HEAD(&session->active_session_list_entry); + INIT_LIST_HEAD(&session->sk_session_queue_entry); + kref_init(&session->kref); + + j1939_priv_get(priv); + session->priv = priv; + session->total_message_size = size; + session->state = J1939_SESSION_NEW; + + skb_queue_head_init(&session->skb_queue); + skb_queue_tail(&session->skb_queue, skb); + + skcb = j1939_skb_to_cb(skb); + memcpy(&session->skcb, skcb, sizeof(session->skcb)); + + hrtimer_init(&session->txtimer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + session->txtimer.function = j1939_tp_txtimer; + hrtimer_init(&session->rxtimer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + session->rxtimer.function = j1939_tp_rxtimer; + + netdev_dbg(priv->ndev, "%s: 0x%p: sa: %02x, da: %02x\n", + __func__, session, skcb->addr.sa, skcb->addr.da); + + return session; +} + +static struct +j1939_session *j1939_session_fresh_new(struct j1939_priv *priv, + int size, + const struct j1939_sk_buff_cb *rel_skcb) +{ + struct sk_buff *skb; + struct j1939_sk_buff_cb *skcb; + struct j1939_session *session; + + skb = alloc_skb(size + sizeof(struct can_skb_priv), GFP_ATOMIC); + if (unlikely(!skb)) + return NULL; + + skb->dev = priv->ndev; + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = priv->ndev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + skcb = j1939_skb_to_cb(skb); + memcpy(skcb, rel_skcb, sizeof(*skcb)); + + session = j1939_session_new(priv, skb, size); + if (!session) { + kfree_skb(skb); + return NULL; + } + + /* alloc data area */ + skb_put(skb, size); + /* skb is recounted in j1939_session_new() */ + return session; +} + +int j1939_session_activate(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + struct j1939_session *active = NULL; + int ret = 0; + + j1939_session_list_lock(priv); + if (session->skcb.addr.type != J1939_SIMPLE) + active = j1939_session_get_by_addr_locked(priv, + &priv->active_session_list, + &session->skcb.addr, false, + session->transmission); + if (active) { + j1939_session_put(active); + ret = -EAGAIN; + } else { + WARN_ON_ONCE(session->state != J1939_SESSION_NEW); + list_add_tail(&session->active_session_list_entry, + &priv->active_session_list); + j1939_session_get(session); + session->state = J1939_SESSION_ACTIVE; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", + __func__, session); + } + j1939_session_list_unlock(priv); + + return ret; +} + +static struct +j1939_session *j1939_xtp_rx_rts_session_new(struct j1939_priv *priv, + struct sk_buff *skb) +{ + enum j1939_xtp_abort abort = J1939_XTP_NO_ABORT; + struct j1939_sk_buff_cb skcb = *j1939_skb_to_cb(skb); + struct j1939_session *session; + const u8 *dat; + pgn_t pgn; + int len; + + netdev_dbg(priv->ndev, "%s\n", __func__); + + dat = skb->data; + pgn = j1939_xtp_ctl_to_pgn(dat); + skcb.addr.pgn = pgn; + + if (!j1939_sk_recv_match(priv, &skcb)) + return NULL; + + if (skcb.addr.type == J1939_ETP) { + len = j1939_etp_ctl_to_size(dat); + if (len > J1939_MAX_ETP_PACKET_SIZE) + abort = J1939_XTP_ABORT_FAULT; + else if (len > priv->tp_max_packet_size) + abort = J1939_XTP_ABORT_RESOURCE; + else if (len <= J1939_MAX_TP_PACKET_SIZE) + abort = J1939_XTP_ABORT_FAULT; + } else { + len = j1939_tp_ctl_to_size(dat); + if (len > J1939_MAX_TP_PACKET_SIZE) + abort = J1939_XTP_ABORT_FAULT; + else if (len > priv->tp_max_packet_size) + abort = J1939_XTP_ABORT_RESOURCE; + else if (len < J1939_MIN_TP_PACKET_SIZE) + abort = J1939_XTP_ABORT_FAULT; + } + + if (abort != J1939_XTP_NO_ABORT) { + j1939_xtp_tx_abort(priv, &skcb, true, abort, pgn); + return NULL; + } + + session = j1939_session_fresh_new(priv, len, &skcb); + if (!session) { + j1939_xtp_tx_abort(priv, &skcb, true, + J1939_XTP_ABORT_RESOURCE, pgn); + return NULL; + } + + /* initialize the control buffer: plain copy */ + session->pkt.total = (len + 6) / 7; + session->pkt.block = 0xff; + if (skcb.addr.type != J1939_ETP) { + if (dat[3] != session->pkt.total) + netdev_alert(priv->ndev, "%s: 0x%p: strange total, %u != %u\n", + __func__, session, session->pkt.total, + dat[3]); + session->pkt.total = dat[3]; + session->pkt.block = min(dat[3], dat[4]); + } + + session->pkt.rx = 0; + session->pkt.tx = 0; + + session->tskey = priv->rx_tskey++; + j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_RTS); + + WARN_ON_ONCE(j1939_session_activate(session)); + + return session; +} + +static int j1939_xtp_rx_rts_session_active(struct j1939_session *session, + struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_priv *priv = session->priv; + + if (!session->transmission) { + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + return -EBUSY; + + /* RTS on active session */ + j1939_session_timers_cancel(session); + j1939_session_cancel(session, J1939_XTP_ABORT_BUSY); + } + + if (session->last_cmd != 0) { + /* we received a second rts on the same connection */ + netdev_alert(priv->ndev, "%s: 0x%p: connection exists (%02x %02x). last cmd: %x\n", + __func__, session, skcb->addr.sa, skcb->addr.da, + session->last_cmd); + + j1939_session_timers_cancel(session); + j1939_session_cancel(session, J1939_XTP_ABORT_BUSY); + + return -EBUSY; + } + + if (session->skcb.addr.sa != skcb->addr.sa || + session->skcb.addr.da != skcb->addr.da) + netdev_warn(priv->ndev, "%s: 0x%p: session->skcb.addr.sa=0x%02x skcb->addr.sa=0x%02x session->skcb.addr.da=0x%02x skcb->addr.da=0x%02x\n", + __func__, session, + session->skcb.addr.sa, skcb->addr.sa, + session->skcb.addr.da, skcb->addr.da); + /* make sure 'sa' & 'da' are correct ! + * They may be 'not filled in yet' for sending + * skb's, since they did not pass the Address Claim ever. + */ + session->skcb.addr.sa = skcb->addr.sa; + session->skcb.addr.da = skcb->addr.da; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static void j1939_xtp_rx_rts(struct j1939_priv *priv, struct sk_buff *skb, + bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + u8 cmd = skb->data[0]; + + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + transmitter); + + if (!session) { + if (transmitter) { + /* If we're the transmitter and this function is called, + * we received our own RTS. A session has already been + * created. + * + * For some reasons however it might have been destroyed + * already. So don't create a new one here (using + * "j1939_xtp_rx_rts_session_new()") as this will be a + * receiver session. + * + * The reasons the session is already destroyed might + * be: + * - user space closed socket was and the session was + * aborted + * - session was aborted due to external abort message + */ + return; + } + session = j1939_xtp_rx_rts_session_new(priv, skb); + if (!session) { + if (cmd == J1939_TP_CMD_BAM && j1939_sk_recv_match(priv, skcb)) + netdev_info(priv->ndev, "%s: failed to create TP BAM session\n", + __func__); + return; + } + } else { + if (j1939_xtp_rx_rts_session_active(session, skb)) { + j1939_session_put(session); + return; + } + } + session->last_cmd = cmd; + + if (cmd == J1939_TP_CMD_BAM) { + if (!session->transmission) + j1939_tp_set_rxtimeout(session, 750); + } else { + if (!session->transmission) { + j1939_session_txtimer_cancel(session); + j1939_tp_schedule_txtimer(session, 0); + } + j1939_tp_set_rxtimeout(session, 1250); + } + + j1939_session_put(session); +} + +static void j1939_xtp_rx_dpo_one(struct j1939_session *session, + struct sk_buff *skb) +{ + const u8 *dat = skb->data; + + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + return; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + /* transmitted without problems */ + session->pkt.dpo = j1939_etp_ctl_to_packet(skb->data); + session->last_cmd = dat[0]; + j1939_tp_set_rxtimeout(session, 750); + + if (!session->transmission) + j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_DPO); +} + +static void j1939_xtp_rx_dpo(struct j1939_priv *priv, struct sk_buff *skb, + bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + transmitter); + if (!session) { + netdev_info(priv->ndev, + "%s: no connection found\n", __func__); + return; + } + + j1939_xtp_rx_dpo_one(session, skb); + j1939_session_put(session); +} + +static void j1939_xtp_rx_dat_one(struct j1939_session *session, + struct sk_buff *skb) +{ + enum j1939_xtp_abort abort = J1939_XTP_ABORT_FAULT; + struct j1939_priv *priv = session->priv; + struct j1939_sk_buff_cb *skcb, *se_skcb; + struct sk_buff *se_skb = NULL; + const u8 *dat; + u8 *tpdat; + int offset; + int nbytes; + bool final = false; + bool remain = false; + bool do_cts_eoma = false; + int packet; + + skcb = j1939_skb_to_cb(skb); + dat = skb->data; + if (skb->len != 8) { + /* makes no sense */ + abort = J1939_XTP_ABORT_UNEXPECTED_DATA; + goto out_session_cancel; + } + + switch (session->last_cmd) { + case 0xff: + break; + case J1939_ETP_CMD_DPO: + if (skcb->addr.type == J1939_ETP) + break; + fallthrough; + case J1939_TP_CMD_BAM: + fallthrough; + case J1939_TP_CMD_CTS: + if (skcb->addr.type != J1939_ETP) + break; + fallthrough; + default: + netdev_info(priv->ndev, "%s: 0x%p: last %02x\n", __func__, + session, session->last_cmd); + goto out_session_cancel; + } + + packet = (dat[0] - 1 + session->pkt.dpo); + if (packet > session->pkt.total || + (session->pkt.rx + 1) > session->pkt.total) { + netdev_info(priv->ndev, "%s: 0x%p: should have been completed\n", + __func__, session); + goto out_session_cancel; + } + + se_skb = j1939_session_skb_get_by_offset(session, packet * 7); + if (!se_skb) { + netdev_warn(priv->ndev, "%s: 0x%p: no skb found\n", __func__, + session); + goto out_session_cancel; + } + + se_skcb = j1939_skb_to_cb(se_skb); + offset = packet * 7 - se_skcb->offset; + nbytes = se_skb->len - offset; + if (nbytes > 7) + nbytes = 7; + if (nbytes <= 0 || (nbytes + 1) > skb->len) { + netdev_info(priv->ndev, "%s: 0x%p: nbytes %i, len %i\n", + __func__, session, nbytes, skb->len); + goto out_session_cancel; + } + + tpdat = se_skb->data; + if (!session->transmission) { + memcpy(&tpdat[offset], &dat[1], nbytes); + } else { + int err; + + err = memcmp(&tpdat[offset], &dat[1], nbytes); + if (err) + netdev_err_once(priv->ndev, + "%s: 0x%p: Data of RX-looped back packet (%*ph) doesn't match TX data (%*ph)!\n", + __func__, session, + nbytes, &dat[1], + nbytes, &tpdat[offset]); + } + + if (packet == session->pkt.rx) + session->pkt.rx++; + + if (se_skcb->addr.type != J1939_ETP && + j1939_cb_is_broadcast(&session->skcb)) { + if (session->pkt.rx >= session->pkt.total) + final = true; + else + remain = true; + } else { + /* never final, an EOMA must follow */ + if (session->pkt.rx >= session->pkt.last) + do_cts_eoma = true; + } + + if (final) { + j1939_session_timers_cancel(session); + j1939_session_completed(session); + } else if (remain) { + if (!session->transmission) + j1939_tp_set_rxtimeout(session, 750); + } else if (do_cts_eoma) { + j1939_tp_set_rxtimeout(session, 1250); + if (!session->transmission) + j1939_tp_schedule_txtimer(session, 0); + } else { + j1939_tp_set_rxtimeout(session, 750); + } + session->last_cmd = 0xff; + consume_skb(se_skb); + j1939_session_put(session); + + return; + + out_session_cancel: + kfree_skb(se_skb); + j1939_session_timers_cancel(session); + j1939_session_cancel(session, abort); + j1939_session_put(session); +} + +static void j1939_xtp_rx_dat(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb; + struct j1939_session *session; + + skcb = j1939_skb_to_cb(skb); + + if (j1939_tp_im_transmitter(skcb)) { + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + true); + if (!session) + netdev_info(priv->ndev, "%s: no tx connection found\n", + __func__); + else + j1939_xtp_rx_dat_one(session, skb); + } + + if (j1939_tp_im_receiver(skcb)) { + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + false); + if (!session) + netdev_info(priv->ndev, "%s: no rx connection found\n", + __func__); + else + j1939_xtp_rx_dat_one(session, skb); + } + + if (j1939_cb_is_broadcast(skcb)) { + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + false); + if (session) + j1939_xtp_rx_dat_one(session, skb); + } +} + +/* j1939 main intf */ +struct j1939_session *j1939_tp_send(struct j1939_priv *priv, + struct sk_buff *skb, size_t size) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + int ret; + + if (skcb->addr.pgn == J1939_TP_PGN_DAT || + skcb->addr.pgn == J1939_TP_PGN_CTL || + skcb->addr.pgn == J1939_ETP_PGN_DAT || + skcb->addr.pgn == J1939_ETP_PGN_CTL) + /* avoid conflict */ + return ERR_PTR(-EDOM); + + if (size > priv->tp_max_packet_size) + return ERR_PTR(-EMSGSIZE); + + if (size <= 8) + skcb->addr.type = J1939_SIMPLE; + else if (size > J1939_MAX_TP_PACKET_SIZE) + skcb->addr.type = J1939_ETP; + else + skcb->addr.type = J1939_TP; + + if (skcb->addr.type == J1939_ETP && + j1939_cb_is_broadcast(skcb)) + return ERR_PTR(-EDESTADDRREQ); + + /* fill in addresses from names */ + ret = j1939_ac_fixup(priv, skb); + if (unlikely(ret)) + return ERR_PTR(ret); + + /* fix DST flags, it may be used there soon */ + if (j1939_address_is_unicast(skcb->addr.da) && + priv->ents[skcb->addr.da].nusers) + skcb->flags |= J1939_ECU_LOCAL_DST; + + /* src is always local, I'm sending ... */ + skcb->flags |= J1939_ECU_LOCAL_SRC; + + /* prepare new session */ + session = j1939_session_new(priv, skb, size); + if (!session) + return ERR_PTR(-ENOMEM); + + /* skb is recounted in j1939_session_new() */ + sock_hold(skb->sk); + session->sk = skb->sk; + session->transmission = true; + session->pkt.total = (size + 6) / 7; + session->pkt.block = skcb->addr.type == J1939_ETP ? 255 : + min(j1939_tp_block ?: 255, session->pkt.total); + + if (j1939_cb_is_broadcast(&session->skcb)) + /* set the end-packet for broadcast */ + session->pkt.last = session->pkt.total; + + skcb->tskey = atomic_inc_return(&session->sk->sk_tskey) - 1; + session->tskey = skcb->tskey; + + return session; +} + +static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + int extd = J1939_TP; + u8 cmd = skb->data[0]; + + switch (cmd) { + case J1939_ETP_CMD_RTS: + extd = J1939_ETP; + fallthrough; + case J1939_TP_CMD_BAM: + if (cmd == J1939_TP_CMD_BAM && !j1939_cb_is_broadcast(skcb)) { + netdev_err_once(priv->ndev, "%s: BAM to unicast (%02x), ignoring!\n", + __func__, skcb->addr.sa); + return; + } + fallthrough; + case J1939_TP_CMD_RTS: + if (skcb->addr.type != extd) + return; + + if (cmd == J1939_TP_CMD_RTS && j1939_cb_is_broadcast(skcb)) { + netdev_alert(priv->ndev, "%s: rts without destination (%02x)\n", + __func__, skcb->addr.sa); + return; + } + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_rts(priv, skb, true); + + if (j1939_tp_im_receiver(skcb) || j1939_cb_is_broadcast(skcb)) + j1939_xtp_rx_rts(priv, skb, false); + + break; + + case J1939_ETP_CMD_CTS: + extd = J1939_ETP; + fallthrough; + case J1939_TP_CMD_CTS: + if (skcb->addr.type != extd) + return; + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_cts(priv, skb, false); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_cts(priv, skb, true); + + break; + + case J1939_ETP_CMD_DPO: + if (skcb->addr.type != J1939_ETP) + return; + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_dpo(priv, skb, true); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_dpo(priv, skb, false); + + break; + + case J1939_ETP_CMD_EOMA: + extd = J1939_ETP; + fallthrough; + case J1939_TP_CMD_EOMA: + if (skcb->addr.type != extd) + return; + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_eoma(priv, skb, false); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_eoma(priv, skb, true); + + break; + + case J1939_ETP_CMD_ABORT: /* && J1939_TP_CMD_ABORT */ + if (j1939_cb_is_broadcast(skcb)) { + netdev_err_once(priv->ndev, "%s: abort to broadcast (%02x), ignoring!\n", + __func__, skcb->addr.sa); + return; + } + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_abort(priv, skb, true); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_abort(priv, skb, false); + + break; + default: + return; + } +} + +int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + + if (!j1939_tp_im_involved_anydir(skcb) && !j1939_cb_is_broadcast(skcb)) + return 0; + + switch (skcb->addr.pgn) { + case J1939_ETP_PGN_DAT: + skcb->addr.type = J1939_ETP; + fallthrough; + case J1939_TP_PGN_DAT: + j1939_xtp_rx_dat(priv, skb); + break; + + case J1939_ETP_PGN_CTL: + skcb->addr.type = J1939_ETP; + fallthrough; + case J1939_TP_PGN_CTL: + if (skb->len < 8) + return 0; /* Don't care. Nothing to extract here */ + + j1939_tp_cmd_recv(priv, skb); + break; + default: + return 0; /* no problem */ + } + return 1; /* "I processed the message" */ +} + +void j1939_simple_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_session *session; + + if (!skb->sk) + return; + + if (skb->sk->sk_family != AF_CAN || + skb->sk->sk_protocol != CAN_J1939) + return; + + j1939_session_list_lock(priv); + session = j1939_session_get_simple(priv, skb); + j1939_session_list_unlock(priv); + if (!session) { + netdev_warn(priv->ndev, + "%s: Received already invalidated message\n", + __func__); + return; + } + + j1939_session_timers_cancel(session); + j1939_session_deactivate(session); + j1939_session_put(session); +} + +int j1939_cancel_active_session(struct j1939_priv *priv, struct sock *sk) +{ + struct j1939_session *session, *saved; + + netdev_dbg(priv->ndev, "%s, sk: %p\n", __func__, sk); + j1939_session_list_lock(priv); + list_for_each_entry_safe(session, saved, + &priv->active_session_list, + active_session_list_entry) { + if (!sk || sk == session->sk) { + if (hrtimer_try_to_cancel(&session->txtimer) == 1) + j1939_session_put(session); + if (hrtimer_try_to_cancel(&session->rxtimer) == 1) + j1939_session_put(session); + + session->err = ESHUTDOWN; + j1939_session_deactivate_locked(session); + } + } + j1939_session_list_unlock(priv); + return NOTIFY_DONE; +} + +void j1939_tp_init(struct j1939_priv *priv) +{ + spin_lock_init(&priv->active_session_list_lock); + INIT_LIST_HEAD(&priv->active_session_list); + priv->tp_max_packet_size = J1939_MAX_ETP_PACKET_SIZE; +} diff --git a/net/can/proc.c b/net/can/proc.c new file mode 100644 index 000000000..bbce97825 --- /dev/null +++ b/net/can/proc.c @@ -0,0 +1,498 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* + * proc.c - procfs support for Protocol family CAN core module + * + * Copyright (c) 2002-2007 Volkswagen Group Electronic Research + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Volkswagen nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * Alternatively, provided that this notice is retained in full, this + * software may be distributed under the terms of the GNU General + * Public License ("GPL") version 2, in which case the provisions of the + * GPL apply INSTEAD OF those given above. + * + * The provided data structures and external interfaces from this code + * are not restricted to be used by modules with a GPL compatible license. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + */ + +#include <linux/module.h> +#include <linux/proc_fs.h> +#include <linux/list.h> +#include <linux/rcupdate.h> +#include <linux/if_arp.h> +#include <linux/can/can-ml.h> +#include <linux/can/core.h> + +#include "af_can.h" + +/* + * proc filenames for the PF_CAN core + */ + +#define CAN_PROC_STATS "stats" +#define CAN_PROC_RESET_STATS "reset_stats" +#define CAN_PROC_RCVLIST_ALL "rcvlist_all" +#define CAN_PROC_RCVLIST_FIL "rcvlist_fil" +#define CAN_PROC_RCVLIST_INV "rcvlist_inv" +#define CAN_PROC_RCVLIST_SFF "rcvlist_sff" +#define CAN_PROC_RCVLIST_EFF "rcvlist_eff" +#define CAN_PROC_RCVLIST_ERR "rcvlist_err" + +static int user_reset; + +static const char rx_list_name[][8] = { + [RX_ERR] = "rx_err", + [RX_ALL] = "rx_all", + [RX_FIL] = "rx_fil", + [RX_INV] = "rx_inv", +}; + +/* + * af_can statistics stuff + */ + +static void can_init_stats(struct net *net) +{ + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats; + /* + * This memset function is called from a timer context (when + * can_stattimer is active which is the default) OR in a process + * context (reading the proc_fs when can_stattimer is disabled). + */ + memset(pkg_stats, 0, sizeof(struct can_pkg_stats)); + pkg_stats->jiffies_init = jiffies; + + rcv_lists_stats->stats_reset++; + + if (user_reset) { + user_reset = 0; + rcv_lists_stats->user_reset++; + } +} + +static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif, + unsigned long count) +{ + if (oldjif == newjif) + return 0; + + /* see can_stat_update() - this should NEVER happen! */ + if (count > (ULONG_MAX / HZ)) { + printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n", + count); + return 99999999; + } + + return (count * HZ) / (newjif - oldjif); +} + +void can_stat_update(struct timer_list *t) +{ + struct net *net = from_timer(net, t, can.stattimer); + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + unsigned long j = jiffies; /* snapshot */ + + /* restart counting in timer context on user request */ + if (user_reset) + can_init_stats(net); + + /* restart counting on jiffies overflow */ + if (j < pkg_stats->jiffies_init) + can_init_stats(net); + + /* prevent overflow in calc_rate() */ + if (pkg_stats->rx_frames > (ULONG_MAX / HZ)) + can_init_stats(net); + + /* prevent overflow in calc_rate() */ + if (pkg_stats->tx_frames > (ULONG_MAX / HZ)) + can_init_stats(net); + + /* matches overflow - very improbable */ + if (pkg_stats->matches > (ULONG_MAX / 100)) + can_init_stats(net); + + /* calc total values */ + if (pkg_stats->rx_frames) + pkg_stats->total_rx_match_ratio = (pkg_stats->matches * 100) / + pkg_stats->rx_frames; + + pkg_stats->total_tx_rate = calc_rate(pkg_stats->jiffies_init, j, + pkg_stats->tx_frames); + pkg_stats->total_rx_rate = calc_rate(pkg_stats->jiffies_init, j, + pkg_stats->rx_frames); + + /* calc current values */ + if (pkg_stats->rx_frames_delta) + pkg_stats->current_rx_match_ratio = + (pkg_stats->matches_delta * 100) / + pkg_stats->rx_frames_delta; + + pkg_stats->current_tx_rate = calc_rate(0, HZ, pkg_stats->tx_frames_delta); + pkg_stats->current_rx_rate = calc_rate(0, HZ, pkg_stats->rx_frames_delta); + + /* check / update maximum values */ + if (pkg_stats->max_tx_rate < pkg_stats->current_tx_rate) + pkg_stats->max_tx_rate = pkg_stats->current_tx_rate; + + if (pkg_stats->max_rx_rate < pkg_stats->current_rx_rate) + pkg_stats->max_rx_rate = pkg_stats->current_rx_rate; + + if (pkg_stats->max_rx_match_ratio < pkg_stats->current_rx_match_ratio) + pkg_stats->max_rx_match_ratio = pkg_stats->current_rx_match_ratio; + + /* clear values for 'current rate' calculation */ + pkg_stats->tx_frames_delta = 0; + pkg_stats->rx_frames_delta = 0; + pkg_stats->matches_delta = 0; + + /* restart timer (one second) */ + mod_timer(&net->can.stattimer, round_jiffies(jiffies + HZ)); +} + +/* + * proc read functions + */ + +static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list, + struct net_device *dev) +{ + struct receiver *r; + + hlist_for_each_entry_rcu(r, rx_list, list) { + char *fmt = (r->can_id & CAN_EFF_FLAG)? + " %-5s %08x %08x %pK %pK %8ld %s\n" : + " %-5s %03x %08x %pK %pK %8ld %s\n"; + + seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask, + r->func, r->data, r->matches, r->ident); + } +} + +static void can_print_recv_banner(struct seq_file *m) +{ + /* + * can1. 00000000 00000000 00000000 + * ....... 0 tp20 + */ + if (IS_ENABLED(CONFIG_64BIT)) + seq_puts(m, " device can_id can_mask function userdata matches ident\n"); + else + seq_puts(m, " device can_id can_mask function userdata matches ident\n"); +} + +static int can_stats_proc_show(struct seq_file *m, void *v) +{ + struct net *net = m->private; + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats; + + seq_putc(m, '\n'); + seq_printf(m, " %8ld transmitted frames (TXF)\n", pkg_stats->tx_frames); + seq_printf(m, " %8ld received frames (RXF)\n", pkg_stats->rx_frames); + seq_printf(m, " %8ld matched frames (RXMF)\n", pkg_stats->matches); + + seq_putc(m, '\n'); + + if (net->can.stattimer.function == can_stat_update) { + seq_printf(m, " %8ld %% total match ratio (RXMR)\n", + pkg_stats->total_rx_match_ratio); + + seq_printf(m, " %8ld frames/s total tx rate (TXR)\n", + pkg_stats->total_tx_rate); + seq_printf(m, " %8ld frames/s total rx rate (RXR)\n", + pkg_stats->total_rx_rate); + + seq_putc(m, '\n'); + + seq_printf(m, " %8ld %% current match ratio (CRXMR)\n", + pkg_stats->current_rx_match_ratio); + + seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n", + pkg_stats->current_tx_rate); + seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n", + pkg_stats->current_rx_rate); + + seq_putc(m, '\n'); + + seq_printf(m, " %8ld %% max match ratio (MRXMR)\n", + pkg_stats->max_rx_match_ratio); + + seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n", + pkg_stats->max_tx_rate); + seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n", + pkg_stats->max_rx_rate); + + seq_putc(m, '\n'); + } + + seq_printf(m, " %8ld current receive list entries (CRCV)\n", + rcv_lists_stats->rcv_entries); + seq_printf(m, " %8ld maximum receive list entries (MRCV)\n", + rcv_lists_stats->rcv_entries_max); + + if (rcv_lists_stats->stats_reset) + seq_printf(m, "\n %8ld statistic resets (STR)\n", + rcv_lists_stats->stats_reset); + + if (rcv_lists_stats->user_reset) + seq_printf(m, " %8ld user statistic resets (USTR)\n", + rcv_lists_stats->user_reset); + + seq_putc(m, '\n'); + return 0; +} + +static int can_reset_stats_proc_show(struct seq_file *m, void *v) +{ + struct net *net = m->private; + struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats; + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + + user_reset = 1; + + if (net->can.stattimer.function == can_stat_update) { + seq_printf(m, "Scheduled statistic reset #%ld.\n", + rcv_lists_stats->stats_reset + 1); + } else { + if (pkg_stats->jiffies_init != jiffies) + can_init_stats(net); + + seq_printf(m, "Performed statistic reset #%ld.\n", + rcv_lists_stats->stats_reset); + } + return 0; +} + +static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx, + struct net_device *dev, + struct can_dev_rcv_lists *dev_rcv_lists) +{ + if (!hlist_empty(&dev_rcv_lists->rx[idx])) { + can_print_recv_banner(m); + can_print_rcvlist(m, &dev_rcv_lists->rx[idx], dev); + } else + seq_printf(m, " (%s: no entry)\n", DNAME(dev)); + +} + +static int can_rcvlist_proc_show(struct seq_file *m, void *v) +{ + /* double cast to prevent GCC warning */ + int idx = (int)(long)pde_data(m->file->f_inode); + struct net_device *dev; + struct can_dev_rcv_lists *dev_rcv_lists; + struct net *net = m->private; + + seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]); + + rcu_read_lock(); + + /* receive list for 'all' CAN devices (dev == NULL) */ + dev_rcv_lists = net->can.rx_alldev_list; + can_rcvlist_proc_show_one(m, idx, NULL, dev_rcv_lists); + + /* receive list for registered CAN devices */ + for_each_netdev_rcu(net, dev) { + struct can_ml_priv *can_ml = can_get_ml_priv(dev); + + if (can_ml) + can_rcvlist_proc_show_one(m, idx, dev, + &can_ml->dev_rcv_lists); + } + + rcu_read_unlock(); + + seq_putc(m, '\n'); + return 0; +} + +static inline void can_rcvlist_proc_show_array(struct seq_file *m, + struct net_device *dev, + struct hlist_head *rcv_array, + unsigned int rcv_array_sz) +{ + unsigned int i; + int all_empty = 1; + + /* check whether at least one list is non-empty */ + for (i = 0; i < rcv_array_sz; i++) + if (!hlist_empty(&rcv_array[i])) { + all_empty = 0; + break; + } + + if (!all_empty) { + can_print_recv_banner(m); + for (i = 0; i < rcv_array_sz; i++) { + if (!hlist_empty(&rcv_array[i])) + can_print_rcvlist(m, &rcv_array[i], dev); + } + } else + seq_printf(m, " (%s: no entry)\n", DNAME(dev)); +} + +static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v) +{ + struct net_device *dev; + struct can_dev_rcv_lists *dev_rcv_lists; + struct net *net = m->private; + + /* RX_SFF */ + seq_puts(m, "\nreceive list 'rx_sff':\n"); + + rcu_read_lock(); + + /* sff receive list for 'all' CAN devices (dev == NULL) */ + dev_rcv_lists = net->can.rx_alldev_list; + can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_sff, + ARRAY_SIZE(dev_rcv_lists->rx_sff)); + + /* sff receive list for registered CAN devices */ + for_each_netdev_rcu(net, dev) { + struct can_ml_priv *can_ml = can_get_ml_priv(dev); + + if (can_ml) { + dev_rcv_lists = &can_ml->dev_rcv_lists; + can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff, + ARRAY_SIZE(dev_rcv_lists->rx_sff)); + } + } + + rcu_read_unlock(); + + seq_putc(m, '\n'); + return 0; +} + +static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v) +{ + struct net_device *dev; + struct can_dev_rcv_lists *dev_rcv_lists; + struct net *net = m->private; + + /* RX_EFF */ + seq_puts(m, "\nreceive list 'rx_eff':\n"); + + rcu_read_lock(); + + /* eff receive list for 'all' CAN devices (dev == NULL) */ + dev_rcv_lists = net->can.rx_alldev_list; + can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_eff, + ARRAY_SIZE(dev_rcv_lists->rx_eff)); + + /* eff receive list for registered CAN devices */ + for_each_netdev_rcu(net, dev) { + struct can_ml_priv *can_ml = can_get_ml_priv(dev); + + if (can_ml) { + dev_rcv_lists = &can_ml->dev_rcv_lists; + can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_eff, + ARRAY_SIZE(dev_rcv_lists->rx_eff)); + } + } + + rcu_read_unlock(); + + seq_putc(m, '\n'); + return 0; +} + +/* + * can_init_proc - create main CAN proc directory and procfs entries + */ +void can_init_proc(struct net *net) +{ + /* create /proc/net/can directory */ + net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net); + + if (!net->can.proc_dir) { + printk(KERN_INFO "can: failed to create /proc/net/can . " + "CONFIG_PROC_FS missing?\n"); + return; + } + + /* own procfs entries from the AF_CAN core */ + net->can.pde_stats = proc_create_net_single(CAN_PROC_STATS, 0644, + net->can.proc_dir, can_stats_proc_show, NULL); + net->can.pde_reset_stats = proc_create_net_single(CAN_PROC_RESET_STATS, + 0644, net->can.proc_dir, can_reset_stats_proc_show, + NULL); + net->can.pde_rcvlist_err = proc_create_net_single(CAN_PROC_RCVLIST_ERR, + 0644, net->can.proc_dir, can_rcvlist_proc_show, + (void *)RX_ERR); + net->can.pde_rcvlist_all = proc_create_net_single(CAN_PROC_RCVLIST_ALL, + 0644, net->can.proc_dir, can_rcvlist_proc_show, + (void *)RX_ALL); + net->can.pde_rcvlist_fil = proc_create_net_single(CAN_PROC_RCVLIST_FIL, + 0644, net->can.proc_dir, can_rcvlist_proc_show, + (void *)RX_FIL); + net->can.pde_rcvlist_inv = proc_create_net_single(CAN_PROC_RCVLIST_INV, + 0644, net->can.proc_dir, can_rcvlist_proc_show, + (void *)RX_INV); + net->can.pde_rcvlist_eff = proc_create_net_single(CAN_PROC_RCVLIST_EFF, + 0644, net->can.proc_dir, can_rcvlist_eff_proc_show, NULL); + net->can.pde_rcvlist_sff = proc_create_net_single(CAN_PROC_RCVLIST_SFF, + 0644, net->can.proc_dir, can_rcvlist_sff_proc_show, NULL); +} + +/* + * can_remove_proc - remove procfs entries and main CAN proc directory + */ +void can_remove_proc(struct net *net) +{ + if (!net->can.proc_dir) + return; + + if (net->can.pde_stats) + remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir); + + if (net->can.pde_reset_stats) + remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir); + + if (net->can.pde_rcvlist_err) + remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir); + + if (net->can.pde_rcvlist_all) + remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir); + + if (net->can.pde_rcvlist_fil) + remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir); + + if (net->can.pde_rcvlist_inv) + remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir); + + if (net->can.pde_rcvlist_eff) + remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir); + + if (net->can.pde_rcvlist_sff) + remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir); + + remove_proc_entry("can", net->proc_net); +} diff --git a/net/can/raw.c b/net/can/raw.c new file mode 100644 index 000000000..d50c3f3d8 --- /dev/null +++ b/net/can/raw.c @@ -0,0 +1,1024 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* raw.c - Raw sockets for protocol family CAN + * + * Copyright (c) 2002-2007 Volkswagen Group Electronic Research + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Volkswagen nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * Alternatively, provided that this notice is retained in full, this + * software may be distributed under the terms of the GNU General + * Public License ("GPL") version 2, in which case the provisions of the + * GPL apply INSTEAD OF those given above. + * + * The provided data structures and external interfaces from this code + * are not restricted to be used by modules with a GPL compatible license. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/uio.h> +#include <linux/net.h> +#include <linux/slab.h> +#include <linux/netdevice.h> +#include <linux/socket.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/can.h> +#include <linux/can/core.h> +#include <linux/can/dev.h> /* for can_is_canxl_dev_mtu() */ +#include <linux/can/skb.h> +#include <linux/can/raw.h> +#include <net/sock.h> +#include <net/net_namespace.h> + +MODULE_DESCRIPTION("PF_CAN raw protocol"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>"); +MODULE_ALIAS("can-proto-1"); + +#define RAW_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_ifindex) + +#define MASK_ALL 0 + +/* A raw socket has a list of can_filters attached to it, each receiving + * the CAN frames matching that filter. If the filter list is empty, + * no CAN frames will be received by the socket. The default after + * opening the socket, is to have one filter which receives all frames. + * The filter list is allocated dynamically with the exception of the + * list containing only one item. This common case is optimized by + * storing the single filter in dfilter, to avoid using dynamic memory. + */ + +struct uniqframe { + int skbcnt; + const struct sk_buff *skb; + unsigned int join_rx_count; +}; + +struct raw_sock { + struct sock sk; + int bound; + int ifindex; + struct net_device *dev; + netdevice_tracker dev_tracker; + struct list_head notifier; + int loopback; + int recv_own_msgs; + int fd_frames; + int xl_frames; + int join_filters; + int count; /* number of active filters */ + struct can_filter dfilter; /* default/single filter */ + struct can_filter *filter; /* pointer to filter(s) */ + can_err_mask_t err_mask; + struct uniqframe __percpu *uniq; +}; + +static LIST_HEAD(raw_notifier_list); +static DEFINE_SPINLOCK(raw_notifier_lock); +static struct raw_sock *raw_busy_notifier; + +/* Return pointer to store the extra msg flags for raw_recvmsg(). + * We use the space of one unsigned int beyond the 'struct sockaddr_can' + * in skb->cb. + */ +static inline unsigned int *raw_flags(struct sk_buff *skb) +{ + sock_skb_cb_check_size(sizeof(struct sockaddr_can) + + sizeof(unsigned int)); + + /* return pointer after struct sockaddr_can */ + return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]); +} + +static inline struct raw_sock *raw_sk(const struct sock *sk) +{ + return (struct raw_sock *)sk; +} + +static void raw_rcv(struct sk_buff *oskb, void *data) +{ + struct sock *sk = (struct sock *)data; + struct raw_sock *ro = raw_sk(sk); + struct sockaddr_can *addr; + struct sk_buff *skb; + unsigned int *pflags; + + /* check the received tx sock reference */ + if (!ro->recv_own_msgs && oskb->sk == sk) + return; + + /* make sure to not pass oversized frames to the socket */ + if ((!ro->fd_frames && can_is_canfd_skb(oskb)) || + (!ro->xl_frames && can_is_canxl_skb(oskb))) + return; + + /* eliminate multiple filter matches for the same skb */ + if (this_cpu_ptr(ro->uniq)->skb == oskb && + this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) { + if (!ro->join_filters) + return; + + this_cpu_inc(ro->uniq->join_rx_count); + /* drop frame until all enabled filters matched */ + if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count) + return; + } else { + this_cpu_ptr(ro->uniq)->skb = oskb; + this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt; + this_cpu_ptr(ro->uniq)->join_rx_count = 1; + /* drop first frame to check all enabled filters? */ + if (ro->join_filters && ro->count > 1) + return; + } + + /* clone the given skb to be able to enqueue it into the rcv queue */ + skb = skb_clone(oskb, GFP_ATOMIC); + if (!skb) + return; + + /* Put the datagram to the queue so that raw_recvmsg() can get + * it from there. We need to pass the interface index to + * raw_recvmsg(). We pass a whole struct sockaddr_can in + * skb->cb containing the interface index. + */ + + sock_skb_cb_check_size(sizeof(struct sockaddr_can)); + addr = (struct sockaddr_can *)skb->cb; + memset(addr, 0, sizeof(*addr)); + addr->can_family = AF_CAN; + addr->can_ifindex = skb->dev->ifindex; + + /* add CAN specific message flags for raw_recvmsg() */ + pflags = raw_flags(skb); + *pflags = 0; + if (oskb->sk) + *pflags |= MSG_DONTROUTE; + if (oskb->sk == sk) + *pflags |= MSG_CONFIRM; + + if (sock_queue_rcv_skb(sk, skb) < 0) + kfree_skb(skb); +} + +static int raw_enable_filters(struct net *net, struct net_device *dev, + struct sock *sk, struct can_filter *filter, + int count) +{ + int err = 0; + int i; + + for (i = 0; i < count; i++) { + err = can_rx_register(net, dev, filter[i].can_id, + filter[i].can_mask, + raw_rcv, sk, "raw", sk); + if (err) { + /* clean up successfully registered filters */ + while (--i >= 0) + can_rx_unregister(net, dev, filter[i].can_id, + filter[i].can_mask, + raw_rcv, sk); + break; + } + } + + return err; +} + +static int raw_enable_errfilter(struct net *net, struct net_device *dev, + struct sock *sk, can_err_mask_t err_mask) +{ + int err = 0; + + if (err_mask) + err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG, + raw_rcv, sk, "raw", sk); + + return err; +} + +static void raw_disable_filters(struct net *net, struct net_device *dev, + struct sock *sk, struct can_filter *filter, + int count) +{ + int i; + + for (i = 0; i < count; i++) + can_rx_unregister(net, dev, filter[i].can_id, + filter[i].can_mask, raw_rcv, sk); +} + +static inline void raw_disable_errfilter(struct net *net, + struct net_device *dev, + struct sock *sk, + can_err_mask_t err_mask) + +{ + if (err_mask) + can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG, + raw_rcv, sk); +} + +static inline void raw_disable_allfilters(struct net *net, + struct net_device *dev, + struct sock *sk) +{ + struct raw_sock *ro = raw_sk(sk); + + raw_disable_filters(net, dev, sk, ro->filter, ro->count); + raw_disable_errfilter(net, dev, sk, ro->err_mask); +} + +static int raw_enable_allfilters(struct net *net, struct net_device *dev, + struct sock *sk) +{ + struct raw_sock *ro = raw_sk(sk); + int err; + + err = raw_enable_filters(net, dev, sk, ro->filter, ro->count); + if (!err) { + err = raw_enable_errfilter(net, dev, sk, ro->err_mask); + if (err) + raw_disable_filters(net, dev, sk, ro->filter, + ro->count); + } + + return err; +} + +static void raw_notify(struct raw_sock *ro, unsigned long msg, + struct net_device *dev) +{ + struct sock *sk = &ro->sk; + + if (!net_eq(dev_net(dev), sock_net(sk))) + return; + + if (ro->dev != dev) + return; + + switch (msg) { + case NETDEV_UNREGISTER: + lock_sock(sk); + /* remove current filters & unregister */ + if (ro->bound) { + raw_disable_allfilters(dev_net(dev), dev, sk); + netdev_put(dev, &ro->dev_tracker); + } + + if (ro->count > 1) + kfree(ro->filter); + + ro->ifindex = 0; + ro->bound = 0; + ro->dev = NULL; + ro->count = 0; + release_sock(sk); + + sk->sk_err = ENODEV; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + break; + + case NETDEV_DOWN: + sk->sk_err = ENETDOWN; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + break; + } +} + +static int raw_notifier(struct notifier_block *nb, unsigned long msg, + void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + + if (dev->type != ARPHRD_CAN) + return NOTIFY_DONE; + if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN) + return NOTIFY_DONE; + if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */ + return NOTIFY_DONE; + + spin_lock(&raw_notifier_lock); + list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) { + spin_unlock(&raw_notifier_lock); + raw_notify(raw_busy_notifier, msg, dev); + spin_lock(&raw_notifier_lock); + } + raw_busy_notifier = NULL; + spin_unlock(&raw_notifier_lock); + return NOTIFY_DONE; +} + +static int raw_init(struct sock *sk) +{ + struct raw_sock *ro = raw_sk(sk); + + ro->bound = 0; + ro->ifindex = 0; + ro->dev = NULL; + + /* set default filter to single entry dfilter */ + ro->dfilter.can_id = 0; + ro->dfilter.can_mask = MASK_ALL; + ro->filter = &ro->dfilter; + ro->count = 1; + + /* set default loopback behaviour */ + ro->loopback = 1; + ro->recv_own_msgs = 0; + ro->fd_frames = 0; + ro->xl_frames = 0; + ro->join_filters = 0; + + /* alloc_percpu provides zero'ed memory */ + ro->uniq = alloc_percpu(struct uniqframe); + if (unlikely(!ro->uniq)) + return -ENOMEM; + + /* set notifier */ + spin_lock(&raw_notifier_lock); + list_add_tail(&ro->notifier, &raw_notifier_list); + spin_unlock(&raw_notifier_lock); + + return 0; +} + +static int raw_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct raw_sock *ro; + + if (!sk) + return 0; + + ro = raw_sk(sk); + + spin_lock(&raw_notifier_lock); + while (raw_busy_notifier == ro) { + spin_unlock(&raw_notifier_lock); + schedule_timeout_uninterruptible(1); + spin_lock(&raw_notifier_lock); + } + list_del(&ro->notifier); + spin_unlock(&raw_notifier_lock); + + rtnl_lock(); + lock_sock(sk); + + /* remove current filters & unregister */ + if (ro->bound) { + if (ro->dev) { + raw_disable_allfilters(dev_net(ro->dev), ro->dev, sk); + netdev_put(ro->dev, &ro->dev_tracker); + } else { + raw_disable_allfilters(sock_net(sk), NULL, sk); + } + } + + if (ro->count > 1) + kfree(ro->filter); + + ro->ifindex = 0; + ro->bound = 0; + ro->dev = NULL; + ro->count = 0; + free_percpu(ro->uniq); + + sock_orphan(sk); + sock->sk = NULL; + + release_sock(sk); + rtnl_unlock(); + + sock_put(sk); + + return 0; +} + +static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct sock *sk = sock->sk; + struct raw_sock *ro = raw_sk(sk); + struct net_device *dev = NULL; + int ifindex; + int err = 0; + int notify_enetdown = 0; + + if (len < RAW_MIN_NAMELEN) + return -EINVAL; + if (addr->can_family != AF_CAN) + return -EINVAL; + + rtnl_lock(); + lock_sock(sk); + + if (ro->bound && addr->can_ifindex == ro->ifindex) + goto out; + + if (addr->can_ifindex) { + dev = dev_get_by_index(sock_net(sk), addr->can_ifindex); + if (!dev) { + err = -ENODEV; + goto out; + } + if (dev->type != ARPHRD_CAN) { + err = -ENODEV; + goto out_put_dev; + } + + if (!(dev->flags & IFF_UP)) + notify_enetdown = 1; + + ifindex = dev->ifindex; + + /* filters set by default/setsockopt */ + err = raw_enable_allfilters(sock_net(sk), dev, sk); + if (err) + goto out_put_dev; + + } else { + ifindex = 0; + + /* filters set by default/setsockopt */ + err = raw_enable_allfilters(sock_net(sk), NULL, sk); + } + + if (!err) { + if (ro->bound) { + /* unregister old filters */ + if (ro->dev) { + raw_disable_allfilters(dev_net(ro->dev), + ro->dev, sk); + /* drop reference to old ro->dev */ + netdev_put(ro->dev, &ro->dev_tracker); + } else { + raw_disable_allfilters(sock_net(sk), NULL, sk); + } + } + ro->ifindex = ifindex; + ro->bound = 1; + /* bind() ok -> hold a reference for new ro->dev */ + ro->dev = dev; + if (ro->dev) + netdev_hold(ro->dev, &ro->dev_tracker, GFP_KERNEL); + } + +out_put_dev: + /* remove potential reference from dev_get_by_index() */ + if (dev) + dev_put(dev); +out: + release_sock(sk); + rtnl_unlock(); + + if (notify_enetdown) { + sk->sk_err = ENETDOWN; + if (!sock_flag(sk, SOCK_DEAD)) + sk_error_report(sk); + } + + return err; +} + +static int raw_getname(struct socket *sock, struct sockaddr *uaddr, + int peer) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct sock *sk = sock->sk; + struct raw_sock *ro = raw_sk(sk); + + if (peer) + return -EOPNOTSUPP; + + memset(addr, 0, RAW_MIN_NAMELEN); + addr->can_family = AF_CAN; + addr->can_ifindex = ro->ifindex; + + return RAW_MIN_NAMELEN; +} + +static int raw_setsockopt(struct socket *sock, int level, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct sock *sk = sock->sk; + struct raw_sock *ro = raw_sk(sk); + struct can_filter *filter = NULL; /* dyn. alloc'ed filters */ + struct can_filter sfilter; /* single filter */ + struct net_device *dev = NULL; + can_err_mask_t err_mask = 0; + int fd_frames; + int count = 0; + int err = 0; + + if (level != SOL_CAN_RAW) + return -EINVAL; + + switch (optname) { + case CAN_RAW_FILTER: + if (optlen % sizeof(struct can_filter) != 0) + return -EINVAL; + + if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) + return -EINVAL; + + count = optlen / sizeof(struct can_filter); + + if (count > 1) { + /* filter does not fit into dfilter => alloc space */ + filter = memdup_sockptr(optval, optlen); + if (IS_ERR(filter)) + return PTR_ERR(filter); + } else if (count == 1) { + if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter))) + return -EFAULT; + } + + rtnl_lock(); + lock_sock(sk); + + dev = ro->dev; + if (ro->bound && dev) { + if (dev->reg_state != NETREG_REGISTERED) { + if (count > 1) + kfree(filter); + err = -ENODEV; + goto out_fil; + } + } + + if (ro->bound) { + /* (try to) register the new filters */ + if (count == 1) + err = raw_enable_filters(sock_net(sk), dev, sk, + &sfilter, 1); + else + err = raw_enable_filters(sock_net(sk), dev, sk, + filter, count); + if (err) { + if (count > 1) + kfree(filter); + goto out_fil; + } + + /* remove old filter registrations */ + raw_disable_filters(sock_net(sk), dev, sk, ro->filter, + ro->count); + } + + /* remove old filter space */ + if (ro->count > 1) + kfree(ro->filter); + + /* link new filters to the socket */ + if (count == 1) { + /* copy filter data for single filter */ + ro->dfilter = sfilter; + filter = &ro->dfilter; + } + ro->filter = filter; + ro->count = count; + + out_fil: + release_sock(sk); + rtnl_unlock(); + + break; + + case CAN_RAW_ERR_FILTER: + if (optlen != sizeof(err_mask)) + return -EINVAL; + + if (copy_from_sockptr(&err_mask, optval, optlen)) + return -EFAULT; + + err_mask &= CAN_ERR_MASK; + + rtnl_lock(); + lock_sock(sk); + + dev = ro->dev; + if (ro->bound && dev) { + if (dev->reg_state != NETREG_REGISTERED) { + err = -ENODEV; + goto out_err; + } + } + + /* remove current error mask */ + if (ro->bound) { + /* (try to) register the new err_mask */ + err = raw_enable_errfilter(sock_net(sk), dev, sk, + err_mask); + + if (err) + goto out_err; + + /* remove old err_mask registration */ + raw_disable_errfilter(sock_net(sk), dev, sk, + ro->err_mask); + } + + /* link new err_mask to the socket */ + ro->err_mask = err_mask; + + out_err: + release_sock(sk); + rtnl_unlock(); + + break; + + case CAN_RAW_LOOPBACK: + if (optlen != sizeof(ro->loopback)) + return -EINVAL; + + if (copy_from_sockptr(&ro->loopback, optval, optlen)) + return -EFAULT; + + break; + + case CAN_RAW_RECV_OWN_MSGS: + if (optlen != sizeof(ro->recv_own_msgs)) + return -EINVAL; + + if (copy_from_sockptr(&ro->recv_own_msgs, optval, optlen)) + return -EFAULT; + + break; + + case CAN_RAW_FD_FRAMES: + if (optlen != sizeof(fd_frames)) + return -EINVAL; + + if (copy_from_sockptr(&fd_frames, optval, optlen)) + return -EFAULT; + + /* Enabling CAN XL includes CAN FD */ + if (ro->xl_frames && !fd_frames) + return -EINVAL; + + ro->fd_frames = fd_frames; + break; + + case CAN_RAW_XL_FRAMES: + if (optlen != sizeof(ro->xl_frames)) + return -EINVAL; + + if (copy_from_sockptr(&ro->xl_frames, optval, optlen)) + return -EFAULT; + + /* Enabling CAN XL includes CAN FD */ + if (ro->xl_frames) + ro->fd_frames = ro->xl_frames; + break; + + case CAN_RAW_JOIN_FILTERS: + if (optlen != sizeof(ro->join_filters)) + return -EINVAL; + + if (copy_from_sockptr(&ro->join_filters, optval, optlen)) + return -EFAULT; + + break; + + default: + return -ENOPROTOOPT; + } + return err; +} + +static int raw_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = sock->sk; + struct raw_sock *ro = raw_sk(sk); + int len; + void *val; + int err = 0; + + if (level != SOL_CAN_RAW) + return -EINVAL; + if (get_user(len, optlen)) + return -EFAULT; + if (len < 0) + return -EINVAL; + + switch (optname) { + case CAN_RAW_FILTER: + lock_sock(sk); + if (ro->count > 0) { + int fsize = ro->count * sizeof(struct can_filter); + + /* user space buffer to small for filter list? */ + if (len < fsize) { + /* return -ERANGE and needed space in optlen */ + err = -ERANGE; + if (put_user(fsize, optlen)) + err = -EFAULT; + } else { + if (len > fsize) + len = fsize; + if (copy_to_user(optval, ro->filter, len)) + err = -EFAULT; + } + } else { + len = 0; + } + release_sock(sk); + + if (!err) + err = put_user(len, optlen); + return err; + + case CAN_RAW_ERR_FILTER: + if (len > sizeof(can_err_mask_t)) + len = sizeof(can_err_mask_t); + val = &ro->err_mask; + break; + + case CAN_RAW_LOOPBACK: + if (len > sizeof(int)) + len = sizeof(int); + val = &ro->loopback; + break; + + case CAN_RAW_RECV_OWN_MSGS: + if (len > sizeof(int)) + len = sizeof(int); + val = &ro->recv_own_msgs; + break; + + case CAN_RAW_FD_FRAMES: + if (len > sizeof(int)) + len = sizeof(int); + val = &ro->fd_frames; + break; + + case CAN_RAW_XL_FRAMES: + if (len > sizeof(int)) + len = sizeof(int); + val = &ro->xl_frames; + break; + + case CAN_RAW_JOIN_FILTERS: + if (len > sizeof(int)) + len = sizeof(int); + val = &ro->join_filters; + break; + + default: + return -ENOPROTOOPT; + } + + if (put_user(len, optlen)) + return -EFAULT; + if (copy_to_user(optval, val, len)) + return -EFAULT; + return 0; +} + +static bool raw_bad_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu) +{ + /* Classical CAN -> no checks for flags and device capabilities */ + if (can_is_can_skb(skb)) + return false; + + /* CAN FD -> needs to be enabled and a CAN FD or CAN XL device */ + if (ro->fd_frames && can_is_canfd_skb(skb) && + (mtu == CANFD_MTU || can_is_canxl_dev_mtu(mtu))) + return false; + + /* CAN XL -> needs to be enabled and a CAN XL device */ + if (ro->xl_frames && can_is_canxl_skb(skb) && + can_is_canxl_dev_mtu(mtu)) + return false; + + return true; +} + +static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) +{ + struct sock *sk = sock->sk; + struct raw_sock *ro = raw_sk(sk); + struct sockcm_cookie sockc; + struct sk_buff *skb; + struct net_device *dev; + int ifindex; + int err = -EINVAL; + + /* check for valid CAN frame sizes */ + if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU) + return -EINVAL; + + if (msg->msg_name) { + DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); + + if (msg->msg_namelen < RAW_MIN_NAMELEN) + return -EINVAL; + + if (addr->can_family != AF_CAN) + return -EINVAL; + + ifindex = addr->can_ifindex; + } else { + ifindex = ro->ifindex; + } + + dev = dev_get_by_index(sock_net(sk), ifindex); + if (!dev) + return -ENXIO; + + skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv), + msg->msg_flags & MSG_DONTWAIT, &err); + if (!skb) + goto put_dev; + + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + + /* fill the skb before testing for valid CAN frames */ + err = memcpy_from_msg(skb_put(skb, size), msg, size); + if (err < 0) + goto free_skb; + + err = -EINVAL; + if (raw_bad_txframe(ro, skb, dev->mtu)) + goto free_skb; + + sockcm_init(&sockc, sk); + if (msg->msg_controllen) { + err = sock_cmsg_send(sk, msg, &sockc); + if (unlikely(err)) + goto free_skb; + } + + skb->dev = dev; + skb->priority = sk->sk_priority; + skb->mark = READ_ONCE(sk->sk_mark); + skb->tstamp = sockc.transmit_time; + + skb_setup_tx_timestamp(skb, sockc.tsflags); + + err = can_send(skb, ro->loopback); + + dev_put(dev); + + if (err) + goto send_failed; + + return size; + +free_skb: + kfree_skb(skb); +put_dev: + dev_put(dev); +send_failed: + return err; +} + +static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags) +{ + struct sock *sk = sock->sk; + struct sk_buff *skb; + int err = 0; + + if (flags & MSG_ERRQUEUE) + return sock_recv_errqueue(sk, msg, size, + SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE); + + skb = skb_recv_datagram(sk, flags, &err); + if (!skb) + return err; + + if (size < skb->len) + msg->msg_flags |= MSG_TRUNC; + else + size = skb->len; + + err = memcpy_to_msg(msg, skb->data, size); + if (err < 0) { + skb_free_datagram(sk, skb); + return err; + } + + sock_recv_cmsgs(msg, sk, skb); + + if (msg->msg_name) { + __sockaddr_check_size(RAW_MIN_NAMELEN); + msg->msg_namelen = RAW_MIN_NAMELEN; + memcpy(msg->msg_name, skb->cb, msg->msg_namelen); + } + + /* assign the flags that have been recorded in raw_rcv() */ + msg->msg_flags |= *(raw_flags(skb)); + + skb_free_datagram(sk, skb); + + return size; +} + +static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + /* no ioctls for socket layer -> hand it down to NIC layer */ + return -ENOIOCTLCMD; +} + +static const struct proto_ops raw_ops = { + .family = PF_CAN, + .release = raw_release, + .bind = raw_bind, + .connect = sock_no_connect, + .socketpair = sock_no_socketpair, + .accept = sock_no_accept, + .getname = raw_getname, + .poll = datagram_poll, + .ioctl = raw_sock_no_ioctlcmd, + .gettstamp = sock_gettstamp, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .setsockopt = raw_setsockopt, + .getsockopt = raw_getsockopt, + .sendmsg = raw_sendmsg, + .recvmsg = raw_recvmsg, + .mmap = sock_no_mmap, +}; + +static struct proto raw_proto __read_mostly = { + .name = "CAN_RAW", + .owner = THIS_MODULE, + .obj_size = sizeof(struct raw_sock), + .init = raw_init, +}; + +static const struct can_proto raw_can_proto = { + .type = SOCK_RAW, + .protocol = CAN_RAW, + .ops = &raw_ops, + .prot = &raw_proto, +}; + +static struct notifier_block canraw_notifier = { + .notifier_call = raw_notifier +}; + +static __init int raw_module_init(void) +{ + int err; + + pr_info("can: raw protocol\n"); + + err = register_netdevice_notifier(&canraw_notifier); + if (err) + return err; + + err = can_proto_register(&raw_can_proto); + if (err < 0) { + pr_err("can: registration of raw protocol failed\n"); + goto register_proto_failed; + } + + return 0; + +register_proto_failed: + unregister_netdevice_notifier(&canraw_notifier); + return err; +} + +static __exit void raw_module_exit(void) +{ + can_proto_unregister(&raw_can_proto); + unregister_netdevice_notifier(&canraw_notifier); +} + +module_init(raw_module_init); +module_exit(raw_module_exit); |