diff options
Diffstat (limited to 'net/can/j1939/socket.c')
| -rw-r--r-- | net/can/j1939/socket.c | 1249 |
1 files changed, 1249 insertions, 0 deletions
diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c new file mode 100644 index 000000000..906a08d38 --- /dev/null +++ b/net/can/j1939/socket.c @@ -0,0 +1,1249 @@ +// 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 + prandom_u32_max(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 call by the generic networking code, when then + * 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, 0, &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_ts_and_drops(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(void) +{ + 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) +{ + struct sk_buff *stats; + u32 size; + + stats = alloc_skb(j1939_sk_opt_stats_get_size(), 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); + + nla_put_u32(stats, J1939_NLA_BYTES_ACKED, size); + + return stats; +} + +void j1939_sk_errqueue(struct j1939_session *session, + enum j1939_sk_errqueue_type type) +{ + struct j1939_priv *priv = session->priv; + struct sock *sk = session->sk; + struct j1939_sock *jsk; + struct sock_exterr_skb *serr; + struct sk_buff *skb; + char *state = "UNK"; + int err; + + /* currently we have no sk for the RX session */ + if (!sk) + return; + + jsk = j1939_sk(sk); + + if (!(jsk->state & J1939_SOCK_ERRQUEUE)) + return; + + skb = j1939_sk_get_timestamping_opt_stats(session); + 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_ACK: + if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK)) { + kfree_skb(skb); + return; + } + + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_info = SCM_TSTAMP_ACK; + state = "ACK"; + break; + case J1939_ERRQUEUE_SCHED: + if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED)) { + kfree_skb(skb); + return; + } + + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_info = SCM_TSTAMP_SCHED; + state = "SCH"; + break; + case J1939_ERRQUEUE_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 = "ABT"; + break; + default: + netdev_err(priv->ndev, "Unknown errqueue type %i\n", type); + } + + serr->opt_stats = true; + if (sk->sk_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_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->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)) + jsk->sk.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, + .sendpage = sock_no_sendpage, +}; + +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, +}; |