summaryrefslogtreecommitdiffstats
path: root/net/can/raw.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--net/can/raw.c1024
1 files changed, 1024 insertions, 0 deletions
diff --git a/net/can/raw.c b/net/can/raw.c
new file mode 100644
index 000000000..488320738
--- /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 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(ro->fd_frames))
+ return -EINVAL;
+
+ if (copy_from_sockptr(&ro->fd_frames, optval, optlen))
+ return -EFAULT;
+
+ /* Enabling CAN XL includes CAN FD */
+ if (ro->xl_frames && !ro->fd_frames) {
+ ro->fd_frames = ro->xl_frames;
+ return -EINVAL;
+ }
+ 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 = 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,
+ .sendpage = sock_no_sendpage,
+};
+
+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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-05 22:28:08 +0000