/* * net/tipc/socket.c: TIPC socket API * * Copyright (c) 2001-2007, 2012-2019, Ericsson AB * Copyright (c) 2004-2008, 2010-2013, Wind River Systems * Copyright (c) 2020-2021, Red Hat Inc * 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 names of the copyright holders nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * 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 #include #include "core.h" #include "name_table.h" #include "node.h" #include "link.h" #include "name_distr.h" #include "socket.h" #include "bcast.h" #include "netlink.h" #include "group.h" #include "trace.h" #define NAGLE_START_INIT 4 #define NAGLE_START_MAX 1024 #define CONN_TIMEOUT_DEFAULT 8000 /* default connect timeout = 8s */ #define CONN_PROBING_INTV msecs_to_jiffies(3600000) /* [ms] => 1 h */ #define TIPC_MAX_PORT 0xffffffff #define TIPC_MIN_PORT 1 #define TIPC_ACK_RATE 4 /* ACK at 1/4 of rcv window size */ enum { TIPC_LISTEN = TCP_LISTEN, TIPC_ESTABLISHED = TCP_ESTABLISHED, TIPC_OPEN = TCP_CLOSE, TIPC_DISCONNECTING = TCP_CLOSE_WAIT, TIPC_CONNECTING = TCP_SYN_SENT, }; struct sockaddr_pair { struct sockaddr_tipc sock; struct sockaddr_tipc member; }; /** * struct tipc_sock - TIPC socket structure * @sk: socket - interacts with 'port' and with user via the socket API * @conn_type: TIPC type used when connection was established * @conn_instance: TIPC instance used when connection was established * @published: non-zero if port has one or more associated names * @max_pkt: maximum packet size "hint" used when building messages sent by port * @maxnagle: maximum size of msg which can be subject to nagle * @portid: unique port identity in TIPC socket hash table * @phdr: preformatted message header used when sending messages * @cong_links: list of congested links * @publications: list of publications for port * @blocking_link: address of the congested link we are currently sleeping on * @pub_count: total # of publications port has made during its lifetime * @conn_timeout: the time we can wait for an unresponded setup request * @probe_unacked: probe has not received ack yet * @dupl_rcvcnt: number of bytes counted twice, in both backlog and rcv queue * @cong_link_cnt: number of congested links * @snt_unacked: # messages sent by socket, and not yet acked by peer * @snd_win: send window size * @peer_caps: peer capabilities mask * @rcv_unacked: # messages read by user, but not yet acked back to peer * @rcv_win: receive window size * @peer: 'connected' peer for dgram/rdm * @node: hash table node * @mc_method: cookie for use between socket and broadcast layer * @rcu: rcu struct for tipc_sock * @group: TIPC communications group * @oneway: message count in one direction (FIXME) * @nagle_start: current nagle value * @snd_backlog: send backlog count * @msg_acc: messages accepted; used in managing backlog and nagle * @pkt_cnt: TIPC socket packet count * @expect_ack: whether this TIPC socket is expecting an ack * @nodelay: setsockopt() TIPC_NODELAY setting * @group_is_open: TIPC socket group is fully open (FIXME) */ struct tipc_sock { struct sock sk; u32 conn_type; u32 conn_instance; u32 max_pkt; u32 maxnagle; u32 portid; struct tipc_msg phdr; struct list_head cong_links; struct list_head publications; u32 pub_count; atomic_t dupl_rcvcnt; u16 conn_timeout; bool probe_unacked; u16 cong_link_cnt; u16 snt_unacked; u16 snd_win; u16 peer_caps; u16 rcv_unacked; u16 rcv_win; struct sockaddr_tipc peer; struct rhash_head node; struct tipc_mc_method mc_method; struct rcu_head rcu; struct tipc_group *group; u32 oneway; u32 nagle_start; u16 snd_backlog; u16 msg_acc; u16 pkt_cnt; bool expect_ack; bool nodelay; bool group_is_open; bool published; }; static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); static void tipc_data_ready(struct sock *sk); static void tipc_write_space(struct sock *sk); static void tipc_sock_destruct(struct sock *sk); static int tipc_release(struct socket *sock); static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags, bool kern); static void tipc_sk_timeout(struct timer_list *t); static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua); static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua); static int tipc_sk_leave(struct tipc_sock *tsk); static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid); static int tipc_sk_insert(struct tipc_sock *tsk); static void tipc_sk_remove(struct tipc_sock *tsk); static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz); static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz); static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack); static const struct proto_ops packet_ops; static const struct proto_ops stream_ops; static const struct proto_ops msg_ops; static struct proto tipc_proto; static const struct rhashtable_params tsk_rht_params; static u32 tsk_own_node(struct tipc_sock *tsk) { return msg_prevnode(&tsk->phdr); } static u32 tsk_peer_node(struct tipc_sock *tsk) { return msg_destnode(&tsk->phdr); } static u32 tsk_peer_port(struct tipc_sock *tsk) { return msg_destport(&tsk->phdr); } static bool tsk_unreliable(struct tipc_sock *tsk) { return msg_src_droppable(&tsk->phdr) != 0; } static void tsk_set_unreliable(struct tipc_sock *tsk, bool unreliable) { msg_set_src_droppable(&tsk->phdr, unreliable ? 1 : 0); } static bool tsk_unreturnable(struct tipc_sock *tsk) { return msg_dest_droppable(&tsk->phdr) != 0; } static void tsk_set_unreturnable(struct tipc_sock *tsk, bool unreturnable) { msg_set_dest_droppable(&tsk->phdr, unreturnable ? 1 : 0); } static int tsk_importance(struct tipc_sock *tsk) { return msg_importance(&tsk->phdr); } static struct tipc_sock *tipc_sk(const struct sock *sk) { return container_of(sk, struct tipc_sock, sk); } int tsk_set_importance(struct sock *sk, int imp) { if (imp > TIPC_CRITICAL_IMPORTANCE) return -EINVAL; msg_set_importance(&tipc_sk(sk)->phdr, (u32)imp); return 0; } static bool tsk_conn_cong(struct tipc_sock *tsk) { return tsk->snt_unacked > tsk->snd_win; } static u16 tsk_blocks(int len) { return ((len / FLOWCTL_BLK_SZ) + 1); } /* tsk_blocks(): translate a buffer size in bytes to number of * advertisable blocks, taking into account the ratio truesize(len)/len * We can trust that this ratio is always < 4 for len >= FLOWCTL_BLK_SZ */ static u16 tsk_adv_blocks(int len) { return len / FLOWCTL_BLK_SZ / 4; } /* tsk_inc(): increment counter for sent or received data * - If block based flow control is not supported by peer we * fall back to message based ditto, incrementing the counter */ static u16 tsk_inc(struct tipc_sock *tsk, int msglen) { if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL)) return ((msglen / FLOWCTL_BLK_SZ) + 1); return 1; } /* tsk_set_nagle - enable/disable nagle property by manipulating maxnagle */ static void tsk_set_nagle(struct tipc_sock *tsk) { struct sock *sk = &tsk->sk; tsk->maxnagle = 0; if (sk->sk_type != SOCK_STREAM) return; if (tsk->nodelay) return; if (!(tsk->peer_caps & TIPC_NAGLE)) return; /* Limit node local buffer size to avoid receive queue overflow */ if (tsk->max_pkt == MAX_MSG_SIZE) tsk->maxnagle = 1500; else tsk->maxnagle = tsk->max_pkt; } /** * tsk_advance_rx_queue - discard first buffer in socket receive queue * @sk: network socket * * Caller must hold socket lock */ static void tsk_advance_rx_queue(struct sock *sk) { trace_tipc_sk_advance_rx(sk, NULL, TIPC_DUMP_SK_RCVQ, " "); kfree_skb(__skb_dequeue(&sk->sk_receive_queue)); } /* tipc_sk_respond() : send response message back to sender */ static void tipc_sk_respond(struct sock *sk, struct sk_buff *skb, int err) { u32 selector; u32 dnode; u32 onode = tipc_own_addr(sock_net(sk)); if (!tipc_msg_reverse(onode, &skb, err)) return; trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE, "@sk_respond!"); dnode = msg_destnode(buf_msg(skb)); selector = msg_origport(buf_msg(skb)); tipc_node_xmit_skb(sock_net(sk), skb, dnode, selector); } /** * tsk_rej_rx_queue - reject all buffers in socket receive queue * @sk: network socket * @error: response error code * * Caller must hold socket lock */ static void tsk_rej_rx_queue(struct sock *sk, int error) { struct sk_buff *skb; while ((skb = __skb_dequeue(&sk->sk_receive_queue))) tipc_sk_respond(sk, skb, error); } static bool tipc_sk_connected(struct sock *sk) { return sk->sk_state == TIPC_ESTABLISHED; } /* tipc_sk_type_connectionless - check if the socket is datagram socket * @sk: socket * * Returns true if connection less, false otherwise */ static bool tipc_sk_type_connectionless(struct sock *sk) { return sk->sk_type == SOCK_RDM || sk->sk_type == SOCK_DGRAM; } /* tsk_peer_msg - verify if message was sent by connected port's peer * * Handles cases where the node's network address has changed from * the default of <0.0.0> to its configured setting. */ static bool tsk_peer_msg(struct tipc_sock *tsk, struct tipc_msg *msg) { struct sock *sk = &tsk->sk; u32 self = tipc_own_addr(sock_net(sk)); u32 peer_port = tsk_peer_port(tsk); u32 orig_node, peer_node; if (unlikely(!tipc_sk_connected(sk))) return false; if (unlikely(msg_origport(msg) != peer_port)) return false; orig_node = msg_orignode(msg); peer_node = tsk_peer_node(tsk); if (likely(orig_node == peer_node)) return true; if (!orig_node && peer_node == self) return true; if (!peer_node && orig_node == self) return true; return false; } /* tipc_set_sk_state - set the sk_state of the socket * @sk: socket * * Caller must hold socket lock * * Returns 0 on success, errno otherwise */ static int tipc_set_sk_state(struct sock *sk, int state) { int oldsk_state = sk->sk_state; int res = -EINVAL; switch (state) { case TIPC_OPEN: res = 0; break; case TIPC_LISTEN: case TIPC_CONNECTING: if (oldsk_state == TIPC_OPEN) res = 0; break; case TIPC_ESTABLISHED: if (oldsk_state == TIPC_CONNECTING || oldsk_state == TIPC_OPEN) res = 0; break; case TIPC_DISCONNECTING: if (oldsk_state == TIPC_CONNECTING || oldsk_state == TIPC_ESTABLISHED) res = 0; break; } if (!res) sk->sk_state = state; return res; } static int tipc_sk_sock_err(struct socket *sock, long *timeout) { struct sock *sk = sock->sk; int err = sock_error(sk); int typ = sock->type; if (err) return err; if (typ == SOCK_STREAM || typ == SOCK_SEQPACKET) { if (sk->sk_state == TIPC_DISCONNECTING) return -EPIPE; else if (!tipc_sk_connected(sk)) return -ENOTCONN; } if (!*timeout) return -EAGAIN; if (signal_pending(current)) return sock_intr_errno(*timeout); return 0; } #define tipc_wait_for_cond(sock_, timeo_, condition_) \ ({ \ DEFINE_WAIT_FUNC(wait_, woken_wake_function); \ struct sock *sk_; \ int rc_; \ \ while ((rc_ = !(condition_))) { \ /* coupled with smp_wmb() in tipc_sk_proto_rcv() */ \ smp_rmb(); \ sk_ = (sock_)->sk; \ rc_ = tipc_sk_sock_err((sock_), timeo_); \ if (rc_) \ break; \ add_wait_queue(sk_sleep(sk_), &wait_); \ release_sock(sk_); \ *(timeo_) = wait_woken(&wait_, TASK_INTERRUPTIBLE, *(timeo_)); \ sched_annotate_sleep(); \ lock_sock(sk_); \ remove_wait_queue(sk_sleep(sk_), &wait_); \ } \ rc_; \ }) /** * tipc_sk_create - create a TIPC socket * @net: network namespace (must be default network) * @sock: pre-allocated socket structure * @protocol: protocol indicator (must be 0) * @kern: caused by kernel or by userspace? * * This routine creates additional data structures used by the TIPC socket, * initializes them, and links them together. * * Return: 0 on success, errno otherwise */ static int tipc_sk_create(struct net *net, struct socket *sock, int protocol, int kern) { const struct proto_ops *ops; struct sock *sk; struct tipc_sock *tsk; struct tipc_msg *msg; /* Validate arguments */ if (unlikely(protocol != 0)) return -EPROTONOSUPPORT; switch (sock->type) { case SOCK_STREAM: ops = &stream_ops; break; case SOCK_SEQPACKET: ops = &packet_ops; break; case SOCK_DGRAM: case SOCK_RDM: ops = &msg_ops; break; default: return -EPROTOTYPE; } /* Allocate socket's protocol area */ sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto, kern); if (sk == NULL) return -ENOMEM; tsk = tipc_sk(sk); tsk->max_pkt = MAX_PKT_DEFAULT; tsk->maxnagle = 0; tsk->nagle_start = NAGLE_START_INIT; INIT_LIST_HEAD(&tsk->publications); INIT_LIST_HEAD(&tsk->cong_links); msg = &tsk->phdr; /* Finish initializing socket data structures */ sock->ops = ops; sock_init_data(sock, sk); tipc_set_sk_state(sk, TIPC_OPEN); if (tipc_sk_insert(tsk)) { pr_warn("Socket create failed; port number exhausted\n"); return -EINVAL; } /* Ensure tsk is visible before we read own_addr. */ smp_mb(); tipc_msg_init(tipc_own_addr(net), msg, TIPC_LOW_IMPORTANCE, TIPC_NAMED_MSG, NAMED_H_SIZE, 0); msg_set_origport(msg, tsk->portid); timer_setup(&sk->sk_timer, tipc_sk_timeout, 0); sk->sk_shutdown = 0; sk->sk_backlog_rcv = tipc_sk_backlog_rcv; sk->sk_rcvbuf = sysctl_tipc_rmem[1]; sk->sk_data_ready = tipc_data_ready; sk->sk_write_space = tipc_write_space; sk->sk_destruct = tipc_sock_destruct; tsk->conn_timeout = CONN_TIMEOUT_DEFAULT; tsk->group_is_open = true; atomic_set(&tsk->dupl_rcvcnt, 0); /* Start out with safe limits until we receive an advertised window */ tsk->snd_win = tsk_adv_blocks(RCVBUF_MIN); tsk->rcv_win = tsk->snd_win; if (tipc_sk_type_connectionless(sk)) { tsk_set_unreturnable(tsk, true); if (sock->type == SOCK_DGRAM) tsk_set_unreliable(tsk, true); } __skb_queue_head_init(&tsk->mc_method.deferredq); trace_tipc_sk_create(sk, NULL, TIPC_DUMP_NONE, " "); return 0; } static void tipc_sk_callback(struct rcu_head *head) { struct tipc_sock *tsk = container_of(head, struct tipc_sock, rcu); sock_put(&tsk->sk); } /* Caller should hold socket lock for the socket. */ static void __tipc_shutdown(struct socket *sock, int error) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct net *net = sock_net(sk); long timeout = msecs_to_jiffies(CONN_TIMEOUT_DEFAULT); u32 dnode = tsk_peer_node(tsk); struct sk_buff *skb; /* Avoid that hi-prio shutdown msgs bypass msgs in link wakeup queue */ tipc_wait_for_cond(sock, &timeout, (!tsk->cong_link_cnt && !tsk_conn_cong(tsk))); /* Push out delayed messages if in Nagle mode */ tipc_sk_push_backlog(tsk, false); /* Remove pending SYN */ __skb_queue_purge(&sk->sk_write_queue); /* Remove partially received buffer if any */ skb = skb_peek(&sk->sk_receive_queue); if (skb && TIPC_SKB_CB(skb)->bytes_read) { __skb_unlink(skb, &sk->sk_receive_queue); kfree_skb(skb); } /* Reject all unreceived messages if connectionless */ if (tipc_sk_type_connectionless(sk)) { tsk_rej_rx_queue(sk, error); return; } switch (sk->sk_state) { case TIPC_CONNECTING: case TIPC_ESTABLISHED: tipc_set_sk_state(sk, TIPC_DISCONNECTING); tipc_node_remove_conn(net, dnode, tsk->portid); /* Send a FIN+/- to its peer */ skb = __skb_dequeue(&sk->sk_receive_queue); if (skb) { __skb_queue_purge(&sk->sk_receive_queue); tipc_sk_respond(sk, skb, error); break; } skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG, SHORT_H_SIZE, 0, dnode, tsk_own_node(tsk), tsk_peer_port(tsk), tsk->portid, error); if (skb) tipc_node_xmit_skb(net, skb, dnode, tsk->portid); break; case TIPC_LISTEN: /* Reject all SYN messages */ tsk_rej_rx_queue(sk, error); break; default: __skb_queue_purge(&sk->sk_receive_queue); break; } } /** * tipc_release - destroy a TIPC socket * @sock: socket to destroy * * This routine cleans up any messages that are still queued on the socket. * For DGRAM and RDM socket types, all queued messages are rejected. * For SEQPACKET and STREAM socket types, the first message is rejected * and any others are discarded. (If the first message on a STREAM socket * is partially-read, it is discarded and the next one is rejected instead.) * * NOTE: Rejected messages are not necessarily returned to the sender! They * are returned or discarded according to the "destination droppable" setting * specified for the message by the sender. * * Return: 0 on success, errno otherwise */ static int tipc_release(struct socket *sock) { struct sock *sk = sock->sk; struct tipc_sock *tsk; /* * Exit if socket isn't fully initialized (occurs when a failed accept() * releases a pre-allocated child socket that was never used) */ if (sk == NULL) return 0; tsk = tipc_sk(sk); lock_sock(sk); trace_tipc_sk_release(sk, NULL, TIPC_DUMP_ALL, " "); __tipc_shutdown(sock, TIPC_ERR_NO_PORT); sk->sk_shutdown = SHUTDOWN_MASK; tipc_sk_leave(tsk); tipc_sk_withdraw(tsk, NULL); __skb_queue_purge(&tsk->mc_method.deferredq); sk_stop_timer(sk, &sk->sk_timer); tipc_sk_remove(tsk); sock_orphan(sk); /* Reject any messages that accumulated in backlog queue */ release_sock(sk); tipc_dest_list_purge(&tsk->cong_links); tsk->cong_link_cnt = 0; call_rcu(&tsk->rcu, tipc_sk_callback); sock->sk = NULL; return 0; } /** * __tipc_bind - associate or disassocate TIPC name(s) with a socket * @sock: socket structure * @skaddr: socket address describing name(s) and desired operation * @alen: size of socket address data structure * * Name and name sequence binding is indicated using a positive scope value; * a negative scope value unbinds the specified name. Specifying no name * (i.e. a socket address length of 0) unbinds all names from the socket. * * Return: 0 on success, errno otherwise * * NOTE: This routine doesn't need to take the socket lock since it doesn't * access any non-constant socket information. */ static int __tipc_bind(struct socket *sock, struct sockaddr *skaddr, int alen) { struct tipc_uaddr *ua = (struct tipc_uaddr *)skaddr; struct tipc_sock *tsk = tipc_sk(sock->sk); bool unbind = false; if (unlikely(!alen)) return tipc_sk_withdraw(tsk, NULL); if (ua->addrtype == TIPC_SERVICE_ADDR) { ua->addrtype = TIPC_SERVICE_RANGE; ua->sr.upper = ua->sr.lower; } if (ua->scope < 0) { unbind = true; ua->scope = -ua->scope; } /* Users may still use deprecated TIPC_ZONE_SCOPE */ if (ua->scope != TIPC_NODE_SCOPE) ua->scope = TIPC_CLUSTER_SCOPE; if (tsk->group) return -EACCES; if (unbind) return tipc_sk_withdraw(tsk, ua); return tipc_sk_publish(tsk, ua); } int tipc_sk_bind(struct socket *sock, struct sockaddr *skaddr, int alen) { int res; lock_sock(sock->sk); res = __tipc_bind(sock, skaddr, alen); release_sock(sock->sk); return res; } static int tipc_bind(struct socket *sock, struct sockaddr *skaddr, int alen) { struct tipc_uaddr *ua = (struct tipc_uaddr *)skaddr; u32 atype = ua->addrtype; if (alen) { if (!tipc_uaddr_valid(ua, alen)) return -EINVAL; if (atype == TIPC_SOCKET_ADDR) return -EAFNOSUPPORT; if (ua->sr.type < TIPC_RESERVED_TYPES) { pr_warn_once("Can't bind to reserved service type %u\n", ua->sr.type); return -EACCES; } } return tipc_sk_bind(sock, skaddr, alen); } /** * tipc_getname - get port ID of socket or peer socket * @sock: socket structure * @uaddr: area for returned socket address * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID * * Return: 0 on success, errno otherwise * * NOTE: This routine doesn't need to take the socket lock since it only * accesses socket information that is unchanging (or which changes in * a completely predictable manner). */ static int tipc_getname(struct socket *sock, struct sockaddr *uaddr, int peer) { struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr; struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); memset(addr, 0, sizeof(*addr)); if (peer) { if ((!tipc_sk_connected(sk)) && ((peer != 2) || (sk->sk_state != TIPC_DISCONNECTING))) return -ENOTCONN; addr->addr.id.ref = tsk_peer_port(tsk); addr->addr.id.node = tsk_peer_node(tsk); } else { addr->addr.id.ref = tsk->portid; addr->addr.id.node = tipc_own_addr(sock_net(sk)); } addr->addrtype = TIPC_SOCKET_ADDR; addr->family = AF_TIPC; addr->scope = 0; addr->addr.name.domain = 0; return sizeof(*addr); } /** * tipc_poll - read and possibly block on pollmask * @file: file structure associated with the socket * @sock: socket for which to calculate the poll bits * @wait: ??? * * Return: pollmask value * * COMMENTARY: * It appears that the usual socket locking mechanisms are not useful here * since the pollmask info is potentially out-of-date the moment this routine * exits. TCP and other protocols seem to rely on higher level poll routines * to handle any preventable race conditions, so TIPC will do the same ... * * IMPORTANT: The fact that a read or write operation is indicated does NOT * imply that the operation will succeed, merely that it should be performed * and will not block. */ static __poll_t tipc_poll(struct file *file, struct socket *sock, poll_table *wait) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); __poll_t revents = 0; sock_poll_wait(file, sock, wait); trace_tipc_sk_poll(sk, NULL, TIPC_DUMP_ALL, " "); if (sk->sk_shutdown & RCV_SHUTDOWN) revents |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM; if (sk->sk_shutdown == SHUTDOWN_MASK) revents |= EPOLLHUP; switch (sk->sk_state) { case TIPC_ESTABLISHED: if (!tsk->cong_link_cnt && !tsk_conn_cong(tsk)) revents |= EPOLLOUT; fallthrough; case TIPC_LISTEN: case TIPC_CONNECTING: if (!skb_queue_empty_lockless(&sk->sk_receive_queue)) revents |= EPOLLIN | EPOLLRDNORM; break; case TIPC_OPEN: if (tsk->group_is_open && !tsk->cong_link_cnt) revents |= EPOLLOUT; if (!tipc_sk_type_connectionless(sk)) break; if (skb_queue_empty_lockless(&sk->sk_receive_queue)) break; revents |= EPOLLIN | EPOLLRDNORM; break; case TIPC_DISCONNECTING: revents = EPOLLIN | EPOLLRDNORM | EPOLLHUP; break; } return revents; } /** * tipc_sendmcast - send multicast message * @sock: socket structure * @ua: destination address struct * @msg: message to send * @dlen: length of data to send * @timeout: timeout to wait for wakeup * * Called from function tipc_sendmsg(), which has done all sanity checks * Return: the number of bytes sent on success, or errno */ static int tipc_sendmcast(struct socket *sock, struct tipc_uaddr *ua, struct msghdr *msg, size_t dlen, long timeout) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_msg *hdr = &tsk->phdr; struct net *net = sock_net(sk); int mtu = tipc_bcast_get_mtu(net); struct sk_buff_head pkts; struct tipc_nlist dsts; int rc; if (tsk->group) return -EACCES; /* Block or return if any destination link is congested */ rc = tipc_wait_for_cond(sock, &timeout, !tsk->cong_link_cnt); if (unlikely(rc)) return rc; /* Lookup destination nodes */ tipc_nlist_init(&dsts, tipc_own_addr(net)); tipc_nametbl_lookup_mcast_nodes(net, ua, &dsts); if (!dsts.local && !dsts.remote) return -EHOSTUNREACH; /* Build message header */ msg_set_type(hdr, TIPC_MCAST_MSG); msg_set_hdr_sz(hdr, MCAST_H_SIZE); msg_set_lookup_scope(hdr, TIPC_CLUSTER_SCOPE); msg_set_destport(hdr, 0); msg_set_destnode(hdr, 0); msg_set_nametype(hdr, ua->sr.type); msg_set_namelower(hdr, ua->sr.lower); msg_set_nameupper(hdr, ua->sr.upper); /* Build message as chain of buffers */ __skb_queue_head_init(&pkts); rc = tipc_msg_build(hdr, msg, 0, dlen, mtu, &pkts); /* Send message if build was successful */ if (unlikely(rc == dlen)) { trace_tipc_sk_sendmcast(sk, skb_peek(&pkts), TIPC_DUMP_SK_SNDQ, " "); rc = tipc_mcast_xmit(net, &pkts, &tsk->mc_method, &dsts, &tsk->cong_link_cnt); } tipc_nlist_purge(&dsts); return rc ? rc : dlen; } /** * tipc_send_group_msg - send a message to a member in the group * @net: network namespace * @tsk: tipc socket * @m: message to send * @mb: group member * @dnode: destination node * @dport: destination port * @dlen: total length of message data */ static int tipc_send_group_msg(struct net *net, struct tipc_sock *tsk, struct msghdr *m, struct tipc_member *mb, u32 dnode, u32 dport, int dlen) { u16 bc_snd_nxt = tipc_group_bc_snd_nxt(tsk->group); struct tipc_mc_method *method = &tsk->mc_method; int blks = tsk_blocks(GROUP_H_SIZE + dlen); struct tipc_msg *hdr = &tsk->phdr; struct sk_buff_head pkts; int mtu, rc; /* Complete message header */ msg_set_type(hdr, TIPC_GRP_UCAST_MSG); msg_set_hdr_sz(hdr, GROUP_H_SIZE); msg_set_destport(hdr, dport); msg_set_destnode(hdr, dnode); msg_set_grp_bc_seqno(hdr, bc_snd_nxt); /* Build message as chain of buffers */ __skb_queue_head_init(&pkts); mtu = tipc_node_get_mtu(net, dnode, tsk->portid, false); rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts); if (unlikely(rc != dlen)) return rc; /* Send message */ rc = tipc_node_xmit(net, &pkts, dnode, tsk->portid); if (unlikely(rc == -ELINKCONG)) { tipc_dest_push(&tsk->cong_links, dnode, 0); tsk->cong_link_cnt++; } /* Update send window */ tipc_group_update_member(mb, blks); /* A broadcast sent within next EXPIRE period must follow same path */ method->rcast = true; method->mandatory = true; return dlen; } /** * tipc_send_group_unicast - send message to a member in the group * @sock: socket structure * @m: message to send * @dlen: total length of message data * @timeout: timeout to wait for wakeup * * Called from function tipc_sendmsg(), which has done all sanity checks * Return: the number of bytes sent on success, or errno */ static int tipc_send_group_unicast(struct socket *sock, struct msghdr *m, int dlen, long timeout) { struct sock *sk = sock->sk; struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name; int blks = tsk_blocks(GROUP_H_SIZE + dlen); struct tipc_sock *tsk = tipc_sk(sk); struct net *net = sock_net(sk); struct tipc_member *mb = NULL; u32 node, port; int rc; node = ua->sk.node; port = ua->sk.ref; if (!port && !node) return -EHOSTUNREACH; /* Block or return if destination link or member is congested */ rc = tipc_wait_for_cond(sock, &timeout, !tipc_dest_find(&tsk->cong_links, node, 0) && tsk->group && !tipc_group_cong(tsk->group, node, port, blks, &mb)); if (unlikely(rc)) return rc; if (unlikely(!mb)) return -EHOSTUNREACH; rc = tipc_send_group_msg(net, tsk, m, mb, node, port, dlen); return rc ? rc : dlen; } /** * tipc_send_group_anycast - send message to any member with given identity * @sock: socket structure * @m: message to send * @dlen: total length of message data * @timeout: timeout to wait for wakeup * * Called from function tipc_sendmsg(), which has done all sanity checks * Return: the number of bytes sent on success, or errno */ static int tipc_send_group_anycast(struct socket *sock, struct msghdr *m, int dlen, long timeout) { struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name; struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct list_head *cong_links = &tsk->cong_links; int blks = tsk_blocks(GROUP_H_SIZE + dlen); struct tipc_msg *hdr = &tsk->phdr; struct tipc_member *first = NULL; struct tipc_member *mbr = NULL; struct net *net = sock_net(sk); u32 node, port, exclude; struct list_head dsts; int lookups = 0; int dstcnt, rc; bool cong; INIT_LIST_HEAD(&dsts); ua->sa.type = msg_nametype(hdr); ua->scope = msg_lookup_scope(hdr); while (++lookups < 4) { exclude = tipc_group_exclude(tsk->group); first = NULL; /* Look for a non-congested destination member, if any */ while (1) { if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt, exclude, false)) return -EHOSTUNREACH; tipc_dest_pop(&dsts, &node, &port); cong = tipc_group_cong(tsk->group, node, port, blks, &mbr); if (!cong) break; if (mbr == first) break; if (!first) first = mbr; } /* Start over if destination was not in member list */ if (unlikely(!mbr)) continue; if (likely(!cong && !tipc_dest_find(cong_links, node, 0))) break; /* Block or return if destination link or member is congested */ rc = tipc_wait_for_cond(sock, &timeout, !tipc_dest_find(cong_links, node, 0) && tsk->group && !tipc_group_cong(tsk->group, node, port, blks, &mbr)); if (unlikely(rc)) return rc; /* Send, unless destination disappeared while waiting */ if (likely(mbr)) break; } if (unlikely(lookups >= 4)) return -EHOSTUNREACH; rc = tipc_send_group_msg(net, tsk, m, mbr, node, port, dlen); return rc ? rc : dlen; } /** * tipc_send_group_bcast - send message to all members in communication group * @sock: socket structure * @m: message to send * @dlen: total length of message data * @timeout: timeout to wait for wakeup * * Called from function tipc_sendmsg(), which has done all sanity checks * Return: the number of bytes sent on success, or errno */ static int tipc_send_group_bcast(struct socket *sock, struct msghdr *m, int dlen, long timeout) { struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name; struct sock *sk = sock->sk; struct net *net = sock_net(sk); struct tipc_sock *tsk = tipc_sk(sk); struct tipc_nlist *dsts; struct tipc_mc_method *method = &tsk->mc_method; bool ack = method->mandatory && method->rcast; int blks = tsk_blocks(MCAST_H_SIZE + dlen); struct tipc_msg *hdr = &tsk->phdr; int mtu = tipc_bcast_get_mtu(net); struct sk_buff_head pkts; int rc = -EHOSTUNREACH; /* Block or return if any destination link or member is congested */ rc = tipc_wait_for_cond(sock, &timeout, !tsk->cong_link_cnt && tsk->group && !tipc_group_bc_cong(tsk->group, blks)); if (unlikely(rc)) return rc; dsts = tipc_group_dests(tsk->group); if (!dsts->local && !dsts->remote) return -EHOSTUNREACH; /* Complete message header */ if (ua) { msg_set_type(hdr, TIPC_GRP_MCAST_MSG); msg_set_nameinst(hdr, ua->sa.instance); } else { msg_set_type(hdr, TIPC_GRP_BCAST_MSG); msg_set_nameinst(hdr, 0); } msg_set_hdr_sz(hdr, GROUP_H_SIZE); msg_set_destport(hdr, 0); msg_set_destnode(hdr, 0); msg_set_grp_bc_seqno(hdr, tipc_group_bc_snd_nxt(tsk->group)); /* Avoid getting stuck with repeated forced replicasts */ msg_set_grp_bc_ack_req(hdr, ack); /* Build message as chain of buffers */ __skb_queue_head_init(&pkts); rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts); if (unlikely(rc != dlen)) return rc; /* Send message */ rc = tipc_mcast_xmit(net, &pkts, method, dsts, &tsk->cong_link_cnt); if (unlikely(rc)) return rc; /* Update broadcast sequence number and send windows */ tipc_group_update_bc_members(tsk->group, blks, ack); /* Broadcast link is now free to choose method for next broadcast */ method->mandatory = false; method->expires = jiffies; return dlen; } /** * tipc_send_group_mcast - send message to all members with given identity * @sock: socket structure * @m: message to send * @dlen: total length of message data * @timeout: timeout to wait for wakeup * * Called from function tipc_sendmsg(), which has done all sanity checks * Return: the number of bytes sent on success, or errno */ static int tipc_send_group_mcast(struct socket *sock, struct msghdr *m, int dlen, long timeout) { struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name; struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_group *grp = tsk->group; struct tipc_msg *hdr = &tsk->phdr; struct net *net = sock_net(sk); struct list_head dsts; u32 dstcnt, exclude; INIT_LIST_HEAD(&dsts); ua->sa.type = msg_nametype(hdr); ua->scope = msg_lookup_scope(hdr); exclude = tipc_group_exclude(grp); if (!tipc_nametbl_lookup_group(net, ua, &dsts, &dstcnt, exclude, true)) return -EHOSTUNREACH; if (dstcnt == 1) { tipc_dest_pop(&dsts, &ua->sk.node, &ua->sk.ref); return tipc_send_group_unicast(sock, m, dlen, timeout); } tipc_dest_list_purge(&dsts); return tipc_send_group_bcast(sock, m, dlen, timeout); } /** * tipc_sk_mcast_rcv - Deliver multicast messages to all destination sockets * @net: the associated network namespace * @arrvq: queue with arriving messages, to be cloned after destination lookup * @inputq: queue with cloned messages, delivered to socket after dest lookup * * Multi-threaded: parallel calls with reference to same queues may occur */ void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq, struct sk_buff_head *inputq) { u32 self = tipc_own_addr(net); struct sk_buff *skb, *_skb; u32 portid, onode; struct sk_buff_head tmpq; struct list_head dports; struct tipc_msg *hdr; struct tipc_uaddr ua; int user, mtyp, hlen; bool exact; __skb_queue_head_init(&tmpq); INIT_LIST_HEAD(&dports); ua.addrtype = TIPC_SERVICE_RANGE; skb = tipc_skb_peek(arrvq, &inputq->lock); for (; skb; skb = tipc_skb_peek(arrvq, &inputq->lock)) { hdr = buf_msg(skb); user = msg_user(hdr); mtyp = msg_type(hdr); hlen = skb_headroom(skb) + msg_hdr_sz(hdr); onode = msg_orignode(hdr); ua.sr.type = msg_nametype(hdr); if (mtyp == TIPC_GRP_UCAST_MSG || user == GROUP_PROTOCOL) { spin_lock_bh(&inputq->lock); if (skb_peek(arrvq) == skb) { __skb_dequeue(arrvq); __skb_queue_tail(inputq, skb); } kfree_skb(skb); spin_unlock_bh(&inputq->lock); continue; } /* Group messages require exact scope match */ if (msg_in_group(hdr)) { ua.sr.lower = 0; ua.sr.upper = ~0; ua.scope = msg_lookup_scope(hdr); exact = true; } else { /* TIPC_NODE_SCOPE means "any scope" in this context */ if (onode == self) ua.scope = TIPC_NODE_SCOPE; else ua.scope = TIPC_CLUSTER_SCOPE; exact = false; ua.sr.lower = msg_namelower(hdr); ua.sr.upper = msg_nameupper(hdr); } /* Create destination port list: */ tipc_nametbl_lookup_mcast_sockets(net, &ua, exact, &dports); /* Clone message per destination */ while (tipc_dest_pop(&dports, NULL, &portid)) { _skb = __pskb_copy(skb, hlen, GFP_ATOMIC); if (_skb) { msg_set_destport(buf_msg(_skb), portid); __skb_queue_tail(&tmpq, _skb); continue; } pr_warn("Failed to clone mcast rcv buffer\n"); } /* Append to inputq if not already done by other thread */ spin_lock_bh(&inputq->lock); if (skb_peek(arrvq) == skb) { skb_queue_splice_tail_init(&tmpq, inputq); kfree_skb(__skb_dequeue(arrvq)); } spin_unlock_bh(&inputq->lock); __skb_queue_purge(&tmpq); kfree_skb(skb); } tipc_sk_rcv(net, inputq); } /* tipc_sk_push_backlog(): send accumulated buffers in socket write queue * when socket is in Nagle mode */ static void tipc_sk_push_backlog(struct tipc_sock *tsk, bool nagle_ack) { struct sk_buff_head *txq = &tsk->sk.sk_write_queue; struct sk_buff *skb = skb_peek_tail(txq); struct net *net = sock_net(&tsk->sk); u32 dnode = tsk_peer_node(tsk); int rc; if (nagle_ack) { tsk->pkt_cnt += skb_queue_len(txq); if (!tsk->pkt_cnt || tsk->msg_acc / tsk->pkt_cnt < 2) { tsk->oneway = 0; if (tsk->nagle_start < NAGLE_START_MAX) tsk->nagle_start *= 2; tsk->expect_ack = false; pr_debug("tsk %10u: bad nagle %u -> %u, next start %u!\n", tsk->portid, tsk->msg_acc, tsk->pkt_cnt, tsk->nagle_start); } else { tsk->nagle_start = NAGLE_START_INIT; if (skb) { msg_set_ack_required(buf_msg(skb)); tsk->expect_ack = true; } else { tsk->expect_ack = false; } } tsk->msg_acc = 0; tsk->pkt_cnt = 0; } if (!skb || tsk->cong_link_cnt) return; /* Do not send SYN again after congestion */ if (msg_is_syn(buf_msg(skb))) return; if (tsk->msg_acc) tsk->pkt_cnt += skb_queue_len(txq); tsk->snt_unacked += tsk->snd_backlog; tsk->snd_backlog = 0; rc = tipc_node_xmit(net, txq, dnode, tsk->portid); if (rc == -ELINKCONG) tsk->cong_link_cnt = 1; } /** * tipc_sk_conn_proto_rcv - receive a connection mng protocol message * @tsk: receiving socket * @skb: pointer to message buffer. * @inputq: buffer list containing the buffers * @xmitq: output message area */ static void tipc_sk_conn_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb, struct sk_buff_head *inputq, struct sk_buff_head *xmitq) { struct tipc_msg *hdr = buf_msg(skb); u32 onode = tsk_own_node(tsk); struct sock *sk = &tsk->sk; int mtyp = msg_type(hdr); bool was_cong; /* Ignore if connection cannot be validated: */ if (!tsk_peer_msg(tsk, hdr)) { trace_tipc_sk_drop_msg(sk, skb, TIPC_DUMP_NONE, "@proto_rcv!"); goto exit; } if (unlikely(msg_errcode(hdr))) { tipc_set_sk_state(sk, TIPC_DISCONNECTING); tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk), tsk_peer_port(tsk)); sk->sk_state_change(sk); /* State change is ignored if socket already awake, * - convert msg to abort msg and add to inqueue */ msg_set_user(hdr, TIPC_CRITICAL_IMPORTANCE); msg_set_type(hdr, TIPC_CONN_MSG); msg_set_size(hdr, BASIC_H_SIZE); msg_set_hdr_sz(hdr, BASIC_H_SIZE); __skb_queue_tail(inputq, skb); return; } tsk->probe_unacked = false; if (mtyp == CONN_PROBE) { msg_set_type(hdr, CONN_PROBE_REPLY); if (tipc_msg_reverse(onode, &skb, TIPC_OK)) __skb_queue_tail(xmitq, skb); return; } else if (mtyp == CONN_ACK) { was_cong = tsk_conn_cong(tsk); tipc_sk_push_backlog(tsk, msg_nagle_ack(hdr)); tsk->snt_unacked -= msg_conn_ack(hdr); if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) tsk->snd_win = msg_adv_win(hdr); if (was_cong && !tsk_conn_cong(tsk)) sk->sk_write_space(sk); } else if (mtyp != CONN_PROBE_REPLY) { pr_warn("Received unknown CONN_PROTO msg\n"); } exit: kfree_skb(skb); } /** * tipc_sendmsg - send message in connectionless manner * @sock: socket structure * @m: message to send * @dsz: amount of user data to be sent * * Message must have an destination specified explicitly. * Used for SOCK_RDM and SOCK_DGRAM messages, * and for 'SYN' messages on SOCK_SEQPACKET and SOCK_STREAM connections. * (Note: 'SYN+' is prohibited on SOCK_STREAM.) * * Return: the number of bytes sent on success, or errno otherwise */ static int tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dsz) { struct sock *sk = sock->sk; int ret; lock_sock(sk); ret = __tipc_sendmsg(sock, m, dsz); release_sock(sk); return ret; } static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen) { struct sock *sk = sock->sk; struct net *net = sock_net(sk); struct tipc_sock *tsk = tipc_sk(sk); struct tipc_uaddr *ua = (struct tipc_uaddr *)m->msg_name; long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT); struct list_head *clinks = &tsk->cong_links; bool syn = !tipc_sk_type_connectionless(sk); struct tipc_group *grp = tsk->group; struct tipc_msg *hdr = &tsk->phdr; struct tipc_socket_addr skaddr; struct sk_buff_head pkts; int atype, mtu, rc; if (unlikely(dlen > TIPC_MAX_USER_MSG_SIZE)) return -EMSGSIZE; if (ua) { if (!tipc_uaddr_valid(ua, m->msg_namelen)) return -EINVAL; atype = ua->addrtype; } /* If socket belongs to a communication group follow other paths */ if (grp) { if (!ua) return tipc_send_group_bcast(sock, m, dlen, timeout); if (atype == TIPC_SERVICE_ADDR) return tipc_send_group_anycast(sock, m, dlen, timeout); if (atype == TIPC_SOCKET_ADDR) return tipc_send_group_unicast(sock, m, dlen, timeout); if (atype == TIPC_SERVICE_RANGE) return tipc_send_group_mcast(sock, m, dlen, timeout); return -EINVAL; } if (!ua) { ua = (struct tipc_uaddr *)&tsk->peer; if (!syn && ua->family != AF_TIPC) return -EDESTADDRREQ; atype = ua->addrtype; } if (unlikely(syn)) { if (sk->sk_state == TIPC_LISTEN) return -EPIPE; if (sk->sk_state != TIPC_OPEN) return -EISCONN; if (tsk->published) return -EOPNOTSUPP; if (atype == TIPC_SERVICE_ADDR) { tsk->conn_type = ua->sa.type; tsk->conn_instance = ua->sa.instance; } msg_set_syn(hdr, 1); } /* Determine destination */ if (atype == TIPC_SERVICE_RANGE) { return tipc_sendmcast(sock, ua, m, dlen, timeout); } else if (atype == TIPC_SERVICE_ADDR) { skaddr.node = ua->lookup_node; ua->scope = tipc_node2scope(skaddr.node); if (!tipc_nametbl_lookup_anycast(net, ua, &skaddr)) return -EHOSTUNREACH; } else if (atype == TIPC_SOCKET_ADDR) { skaddr = ua->sk; } else { return -EINVAL; } /* Block or return if destination link is congested */ rc = tipc_wait_for_cond(sock, &timeout, !tipc_dest_find(clinks, skaddr.node, 0)); if (unlikely(rc)) return rc; /* Finally build message header */ msg_set_destnode(hdr, skaddr.node); msg_set_destport(hdr, skaddr.ref); if (atype == TIPC_SERVICE_ADDR) { msg_set_type(hdr, TIPC_NAMED_MSG); msg_set_hdr_sz(hdr, NAMED_H_SIZE); msg_set_nametype(hdr, ua->sa.type); msg_set_nameinst(hdr, ua->sa.instance); msg_set_lookup_scope(hdr, ua->scope); } else { /* TIPC_SOCKET_ADDR */ msg_set_type(hdr, TIPC_DIRECT_MSG); msg_set_lookup_scope(hdr, 0); msg_set_hdr_sz(hdr, BASIC_H_SIZE); } /* Add message body */ __skb_queue_head_init(&pkts); mtu = tipc_node_get_mtu(net, skaddr.node, tsk->portid, true); rc = tipc_msg_build(hdr, m, 0, dlen, mtu, &pkts); if (unlikely(rc != dlen)) return rc; if (unlikely(syn && !tipc_msg_skb_clone(&pkts, &sk->sk_write_queue))) { __skb_queue_purge(&pkts); return -ENOMEM; } /* Send message */ trace_tipc_sk_sendmsg(sk, skb_peek(&pkts), TIPC_DUMP_SK_SNDQ, " "); rc = tipc_node_xmit(net, &pkts, skaddr.node, tsk->portid); if (unlikely(rc == -ELINKCONG)) { tipc_dest_push(clinks, skaddr.node, 0); tsk->cong_link_cnt++; rc = 0; } if (unlikely(syn && !rc)) tipc_set_sk_state(sk, TIPC_CONNECTING); return rc ? rc : dlen; } /** * tipc_sendstream - send stream-oriented data * @sock: socket structure * @m: data to send * @dsz: total length of data to be transmitted * * Used for SOCK_STREAM data. * * Return: the number of bytes sent on success (or partial success), * or errno if no data sent */ static int tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dsz) { struct sock *sk = sock->sk; int ret; lock_sock(sk); ret = __tipc_sendstream(sock, m, dsz); release_sock(sk); return ret; } static int __tipc_sendstream(struct socket *sock, struct msghdr *m, size_t dlen) { struct sock *sk = sock->sk; DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name); long timeout = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT); struct sk_buff_head *txq = &sk->sk_write_queue; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_msg *hdr = &tsk->phdr; struct net *net = sock_net(sk); struct sk_buff *skb; u32 dnode = tsk_peer_node(tsk); int maxnagle = tsk->maxnagle; int maxpkt = tsk->max_pkt; int send, sent = 0; int blocks, rc = 0; if (unlikely(dlen > INT_MAX)) return -EMSGSIZE; /* Handle implicit connection setup */ if (unlikely(dest)) { rc = __tipc_sendmsg(sock, m, dlen); if (dlen && dlen == rc) { tsk->peer_caps = tipc_node_get_capabilities(net, dnode); tsk->snt_unacked = tsk_inc(tsk, dlen + msg_hdr_sz(hdr)); } return rc; } do { rc = tipc_wait_for_cond(sock, &timeout, (!tsk->cong_link_cnt && !tsk_conn_cong(tsk) && tipc_sk_connected(sk))); if (unlikely(rc)) break; send = min_t(size_t, dlen - sent, TIPC_MAX_USER_MSG_SIZE); blocks = tsk->snd_backlog; if (tsk->oneway++ >= tsk->nagle_start && maxnagle && send <= maxnagle) { rc = tipc_msg_append(hdr, m, send, maxnagle, txq); if (unlikely(rc < 0)) break; blocks += rc; tsk->msg_acc++; if (blocks <= 64 && tsk->expect_ack) { tsk->snd_backlog = blocks; sent += send; break; } else if (blocks > 64) { tsk->pkt_cnt += skb_queue_len(txq); } else { skb = skb_peek_tail(txq); if (skb) { msg_set_ack_required(buf_msg(skb)); tsk->expect_ack = true; } else { tsk->expect_ack = false; } tsk->msg_acc = 0; tsk->pkt_cnt = 0; } } else { rc = tipc_msg_build(hdr, m, sent, send, maxpkt, txq); if (unlikely(rc != send)) break; blocks += tsk_inc(tsk, send + MIN_H_SIZE); } trace_tipc_sk_sendstream(sk, skb_peek(txq), TIPC_DUMP_SK_SNDQ, " "); rc = tipc_node_xmit(net, txq, dnode, tsk->portid); if (unlikely(rc == -ELINKCONG)) { tsk->cong_link_cnt = 1; rc = 0; } if (likely(!rc)) { tsk->snt_unacked += blocks; tsk->snd_backlog = 0; sent += send; } } while (sent < dlen && !rc); return sent ? sent : rc; } /** * tipc_send_packet - send a connection-oriented message * @sock: socket structure * @m: message to send * @dsz: length of data to be transmitted * * Used for SOCK_SEQPACKET messages. * * Return: the number of bytes sent on success, or errno otherwise */ static int tipc_send_packet(struct socket *sock, struct msghdr *m, size_t dsz) { if (dsz > TIPC_MAX_USER_MSG_SIZE) return -EMSGSIZE; return tipc_sendstream(sock, m, dsz); } /* tipc_sk_finish_conn - complete the setup of a connection */ static void tipc_sk_finish_conn(struct tipc_sock *tsk, u32 peer_port, u32 peer_node) { struct sock *sk = &tsk->sk; struct net *net = sock_net(sk); struct tipc_msg *msg = &tsk->phdr; msg_set_syn(msg, 0); msg_set_destnode(msg, peer_node); msg_set_destport(msg, peer_port); msg_set_type(msg, TIPC_CONN_MSG); msg_set_lookup_scope(msg, 0); msg_set_hdr_sz(msg, SHORT_H_SIZE); sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV); tipc_set_sk_state(sk, TIPC_ESTABLISHED); tipc_node_add_conn(net, peer_node, tsk->portid, peer_port); tsk->max_pkt = tipc_node_get_mtu(net, peer_node, tsk->portid, true); tsk->peer_caps = tipc_node_get_capabilities(net, peer_node); tsk_set_nagle(tsk); __skb_queue_purge(&sk->sk_write_queue); if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) return; /* Fall back to message based flow control */ tsk->rcv_win = FLOWCTL_MSG_WIN; tsk->snd_win = FLOWCTL_MSG_WIN; } /** * tipc_sk_set_orig_addr - capture sender's address for received message * @m: descriptor for message info * @skb: received message * * Note: Address is not captured if not requested by receiver. */ static void tipc_sk_set_orig_addr(struct msghdr *m, struct sk_buff *skb) { DECLARE_SOCKADDR(struct sockaddr_pair *, srcaddr, m->msg_name); struct tipc_msg *hdr = buf_msg(skb); if (!srcaddr) return; srcaddr->sock.family = AF_TIPC; srcaddr->sock.addrtype = TIPC_SOCKET_ADDR; srcaddr->sock.scope = 0; srcaddr->sock.addr.id.ref = msg_origport(hdr); srcaddr->sock.addr.id.node = msg_orignode(hdr); srcaddr->sock.addr.name.domain = 0; m->msg_namelen = sizeof(struct sockaddr_tipc); if (!msg_in_group(hdr)) return; /* Group message users may also want to know sending member's id */ srcaddr->member.family = AF_TIPC; srcaddr->member.addrtype = TIPC_SERVICE_ADDR; srcaddr->member.scope = 0; srcaddr->member.addr.name.name.type = msg_nametype(hdr); srcaddr->member.addr.name.name.instance = TIPC_SKB_CB(skb)->orig_member; srcaddr->member.addr.name.domain = 0; m->msg_namelen = sizeof(*srcaddr); } /** * tipc_sk_anc_data_recv - optionally capture ancillary data for received message * @m: descriptor for message info * @skb: received message buffer * @tsk: TIPC port associated with message * * Note: Ancillary data is not captured if not requested by receiver. * * Return: 0 if successful, otherwise errno */ static int tipc_sk_anc_data_recv(struct msghdr *m, struct sk_buff *skb, struct tipc_sock *tsk) { struct tipc_msg *msg; u32 anc_data[3]; u32 err; u32 dest_type; int has_name; int res; if (likely(m->msg_controllen == 0)) return 0; msg = buf_msg(skb); /* Optionally capture errored message object(s) */ err = msg ? msg_errcode(msg) : 0; if (unlikely(err)) { anc_data[0] = err; anc_data[1] = msg_data_sz(msg); res = put_cmsg(m, SOL_TIPC, TIPC_ERRINFO, 8, anc_data); if (res) return res; if (anc_data[1]) { if (skb_linearize(skb)) return -ENOMEM; msg = buf_msg(skb); res = put_cmsg(m, SOL_TIPC, TIPC_RETDATA, anc_data[1], msg_data(msg)); if (res) return res; } } /* Optionally capture message destination object */ dest_type = msg ? msg_type(msg) : TIPC_DIRECT_MSG; switch (dest_type) { case TIPC_NAMED_MSG: has_name = 1; anc_data[0] = msg_nametype(msg); anc_data[1] = msg_namelower(msg); anc_data[2] = msg_namelower(msg); break; case TIPC_MCAST_MSG: has_name = 1; anc_data[0] = msg_nametype(msg); anc_data[1] = msg_namelower(msg); anc_data[2] = msg_nameupper(msg); break; case TIPC_CONN_MSG: has_name = (tsk->conn_type != 0); anc_data[0] = tsk->conn_type; anc_data[1] = tsk->conn_instance; anc_data[2] = tsk->conn_instance; break; default: has_name = 0; } if (has_name) { res = put_cmsg(m, SOL_TIPC, TIPC_DESTNAME, 12, anc_data); if (res) return res; } return 0; } static struct sk_buff *tipc_sk_build_ack(struct tipc_sock *tsk) { struct sock *sk = &tsk->sk; struct sk_buff *skb = NULL; struct tipc_msg *msg; u32 peer_port = tsk_peer_port(tsk); u32 dnode = tsk_peer_node(tsk); if (!tipc_sk_connected(sk)) return NULL; skb = tipc_msg_create(CONN_MANAGER, CONN_ACK, INT_H_SIZE, 0, dnode, tsk_own_node(tsk), peer_port, tsk->portid, TIPC_OK); if (!skb) return NULL; msg = buf_msg(skb); msg_set_conn_ack(msg, tsk->rcv_unacked); tsk->rcv_unacked = 0; /* Adjust to and advertize the correct window limit */ if (tsk->peer_caps & TIPC_BLOCK_FLOWCTL) { tsk->rcv_win = tsk_adv_blocks(tsk->sk.sk_rcvbuf); msg_set_adv_win(msg, tsk->rcv_win); } return skb; } static void tipc_sk_send_ack(struct tipc_sock *tsk) { struct sk_buff *skb; skb = tipc_sk_build_ack(tsk); if (!skb) return; tipc_node_xmit_skb(sock_net(&tsk->sk), skb, tsk_peer_node(tsk), msg_link_selector(buf_msg(skb))); } static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop) { struct sock *sk = sock->sk; DEFINE_WAIT_FUNC(wait, woken_wake_function); long timeo = *timeop; int err = sock_error(sk); if (err) return err; for (;;) { if (timeo && skb_queue_empty(&sk->sk_receive_queue)) { if (sk->sk_shutdown & RCV_SHUTDOWN) { err = -ENOTCONN; break; } add_wait_queue(sk_sleep(sk), &wait); release_sock(sk); timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo); sched_annotate_sleep(); lock_sock(sk); remove_wait_queue(sk_sleep(sk), &wait); } err = 0; if (!skb_queue_empty(&sk->sk_receive_queue)) break; err = -EAGAIN; if (!timeo) break; err = sock_intr_errno(timeo); if (signal_pending(current)) break; err = sock_error(sk); if (err) break; } *timeop = timeo; return err; } /** * tipc_recvmsg - receive packet-oriented message * @sock: network socket * @m: descriptor for message info * @buflen: length of user buffer area * @flags: receive flags * * Used for SOCK_DGRAM, SOCK_RDM, and SOCK_SEQPACKET messages. * If the complete message doesn't fit in user area, truncate it. * * Return: size of returned message data, errno otherwise */ static int tipc_recvmsg(struct socket *sock, struct msghdr *m, size_t buflen, int flags) { struct sock *sk = sock->sk; bool connected = !tipc_sk_type_connectionless(sk); struct tipc_sock *tsk = tipc_sk(sk); int rc, err, hlen, dlen, copy; struct sk_buff_head xmitq; struct tipc_msg *hdr; struct sk_buff *skb; bool grp_evt; long timeout; /* Catch invalid receive requests */ if (unlikely(!buflen)) return -EINVAL; lock_sock(sk); if (unlikely(connected && sk->sk_state == TIPC_OPEN)) { rc = -ENOTCONN; goto exit; } timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); /* Step rcv queue to first msg with data or error; wait if necessary */ do { rc = tipc_wait_for_rcvmsg(sock, &timeout); if (unlikely(rc)) goto exit; skb = skb_peek(&sk->sk_receive_queue); hdr = buf_msg(skb); dlen = msg_data_sz(hdr); hlen = msg_hdr_sz(hdr); err = msg_errcode(hdr); grp_evt = msg_is_grp_evt(hdr); if (likely(dlen || err)) break; tsk_advance_rx_queue(sk); } while (1); /* Collect msg meta data, including error code and rejected data */ tipc_sk_set_orig_addr(m, skb); rc = tipc_sk_anc_data_recv(m, skb, tsk); if (unlikely(rc)) goto exit; hdr = buf_msg(skb); /* Capture data if non-error msg, otherwise just set return value */ if (likely(!err)) { copy = min_t(int, dlen, buflen); if (unlikely(copy != dlen)) m->msg_flags |= MSG_TRUNC; rc = skb_copy_datagram_msg(skb, hlen, m, copy); } else { copy = 0; rc = 0; if (err != TIPC_CONN_SHUTDOWN && connected && !m->msg_control) rc = -ECONNRESET; } if (unlikely(rc)) goto exit; /* Mark message as group event if applicable */ if (unlikely(grp_evt)) { if (msg_grp_evt(hdr) == TIPC_WITHDRAWN) m->msg_flags |= MSG_EOR; m->msg_flags |= MSG_OOB; copy = 0; } /* Caption of data or error code/rejected data was successful */ if (unlikely(flags & MSG_PEEK)) goto exit; /* Send group flow control advertisement when applicable */ if (tsk->group && msg_in_group(hdr) && !grp_evt) { __skb_queue_head_init(&xmitq); tipc_group_update_rcv_win(tsk->group, tsk_blocks(hlen + dlen), msg_orignode(hdr), msg_origport(hdr), &xmitq); tipc_node_distr_xmit(sock_net(sk), &xmitq); } tsk_advance_rx_queue(sk); if (likely(!connected)) goto exit; /* Send connection flow control advertisement when applicable */ tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen); if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE) tipc_sk_send_ack(tsk); exit: release_sock(sk); return rc ? rc : copy; } /** * tipc_recvstream - receive stream-oriented data * @sock: network socket * @m: descriptor for message info * @buflen: total size of user buffer area * @flags: receive flags * * Used for SOCK_STREAM messages only. If not enough data is available * will optionally wait for more; never truncates data. * * Return: size of returned message data, errno otherwise */ static int tipc_recvstream(struct socket *sock, struct msghdr *m, size_t buflen, int flags) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct sk_buff *skb; struct tipc_msg *hdr; struct tipc_skb_cb *skb_cb; bool peek = flags & MSG_PEEK; int offset, required, copy, copied = 0; int hlen, dlen, err, rc; long timeout; /* Catch invalid receive attempts */ if (unlikely(!buflen)) return -EINVAL; lock_sock(sk); if (unlikely(sk->sk_state == TIPC_OPEN)) { rc = -ENOTCONN; goto exit; } required = sock_rcvlowat(sk, flags & MSG_WAITALL, buflen); timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); do { /* Look at first msg in receive queue; wait if necessary */ rc = tipc_wait_for_rcvmsg(sock, &timeout); if (unlikely(rc)) break; skb = skb_peek(&sk->sk_receive_queue); skb_cb = TIPC_SKB_CB(skb); hdr = buf_msg(skb); dlen = msg_data_sz(hdr); hlen = msg_hdr_sz(hdr); err = msg_errcode(hdr); /* Discard any empty non-errored (SYN-) message */ if (unlikely(!dlen && !err)) { tsk_advance_rx_queue(sk); continue; } /* Collect msg meta data, incl. error code and rejected data */ if (!copied) { tipc_sk_set_orig_addr(m, skb); rc = tipc_sk_anc_data_recv(m, skb, tsk); if (rc) break; hdr = buf_msg(skb); } /* Copy data if msg ok, otherwise return error/partial data */ if (likely(!err)) { offset = skb_cb->bytes_read; copy = min_t(int, dlen - offset, buflen - copied); rc = skb_copy_datagram_msg(skb, hlen + offset, m, copy); if (unlikely(rc)) break; copied += copy; offset += copy; if (unlikely(offset < dlen)) { if (!peek) skb_cb->bytes_read = offset; break; } } else { rc = 0; if ((err != TIPC_CONN_SHUTDOWN) && !m->msg_control) rc = -ECONNRESET; if (copied || rc) break; } if (unlikely(peek)) break; tsk_advance_rx_queue(sk); /* Send connection flow control advertisement when applicable */ tsk->rcv_unacked += tsk_inc(tsk, hlen + dlen); if (tsk->rcv_unacked >= tsk->rcv_win / TIPC_ACK_RATE) tipc_sk_send_ack(tsk); /* Exit if all requested data or FIN/error received */ if (copied == buflen || err) break; } while (!skb_queue_empty(&sk->sk_receive_queue) || copied < required); exit: release_sock(sk); return copied ? copied : rc; } /** * tipc_write_space - wake up thread if port congestion is released * @sk: socket */ static void tipc_write_space(struct sock *sk) { struct socket_wq *wq; rcu_read_lock(); wq = rcu_dereference(sk->sk_wq); if (skwq_has_sleeper(wq)) wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND); rcu_read_unlock(); } /** * tipc_data_ready - wake up threads to indicate messages have been received * @sk: socket */ static void tipc_data_ready(struct sock *sk) { struct socket_wq *wq; rcu_read_lock(); wq = rcu_dereference(sk->sk_wq); if (skwq_has_sleeper(wq)) wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLRDNORM | EPOLLRDBAND); rcu_read_unlock(); } static void tipc_sock_destruct(struct sock *sk) { __skb_queue_purge(&sk->sk_receive_queue); } static void tipc_sk_proto_rcv(struct sock *sk, struct sk_buff_head *inputq, struct sk_buff_head *xmitq) { struct sk_buff *skb = __skb_dequeue(inputq); struct tipc_sock *tsk = tipc_sk(sk); struct tipc_msg *hdr = buf_msg(skb); struct tipc_group *grp = tsk->group; bool wakeup = false; switch (msg_user(hdr)) { case CONN_MANAGER: tipc_sk_conn_proto_rcv(tsk, skb, inputq, xmitq); return; case SOCK_WAKEUP: tipc_dest_del(&tsk->cong_links, msg_orignode(hdr), 0); /* coupled with smp_rmb() in tipc_wait_for_cond() */ smp_wmb(); tsk->cong_link_cnt--; wakeup = true; tipc_sk_push_backlog(tsk, false); break; case GROUP_PROTOCOL: tipc_group_proto_rcv(grp, &wakeup, hdr, inputq, xmitq); break; case TOP_SRV: tipc_group_member_evt(tsk->group, &wakeup, &sk->sk_rcvbuf, hdr, inputq, xmitq); break; default: break; } if (wakeup) sk->sk_write_space(sk); kfree_skb(skb); } /** * tipc_sk_filter_connect - check incoming message for a connection-based socket * @tsk: TIPC socket * @skb: pointer to message buffer. * @xmitq: for Nagle ACK if any * Return: true if message should be added to receive queue, false otherwise */ static bool tipc_sk_filter_connect(struct tipc_sock *tsk, struct sk_buff *skb, struct sk_buff_head *xmitq) { struct sock *sk = &tsk->sk; struct net *net = sock_net(sk); struct tipc_msg *hdr = buf_msg(skb); bool con_msg = msg_connected(hdr); u32 pport = tsk_peer_port(tsk); u32 pnode = tsk_peer_node(tsk); u32 oport = msg_origport(hdr); u32 onode = msg_orignode(hdr); int err = msg_errcode(hdr); unsigned long delay; if (unlikely(msg_mcast(hdr))) return false; tsk->oneway = 0; switch (sk->sk_state) { case TIPC_CONNECTING: /* Setup ACK */ if (likely(con_msg)) { if (err) break; tipc_sk_finish_conn(tsk, oport, onode); msg_set_importance(&tsk->phdr, msg_importance(hdr)); /* ACK+ message with data is added to receive queue */ if (msg_data_sz(hdr)) return true; /* Empty ACK-, - wake up sleeping connect() and drop */ sk->sk_state_change(sk); msg_set_dest_droppable(hdr, 1); return false; } /* Ignore connectionless message if not from listening socket */ if (oport != pport || onode != pnode) return false; /* Rejected SYN */ if (err != TIPC_ERR_OVERLOAD) break; /* Prepare for new setup attempt if we have a SYN clone */ if (skb_queue_empty(&sk->sk_write_queue)) break; get_random_bytes(&delay, 2); delay %= (tsk->conn_timeout / 4); delay = msecs_to_jiffies(delay + 100); sk_reset_timer(sk, &sk->sk_timer, jiffies + delay); return false; case TIPC_OPEN: case TIPC_DISCONNECTING: return false; case TIPC_LISTEN: /* Accept only SYN message */ if (!msg_is_syn(hdr) && tipc_node_get_capabilities(net, onode) & TIPC_SYN_BIT) return false; if (!con_msg && !err) return true; return false; case TIPC_ESTABLISHED: if (!skb_queue_empty(&sk->sk_write_queue)) tipc_sk_push_backlog(tsk, false); /* Accept only connection-based messages sent by peer */ if (likely(con_msg && !err && pport == oport && pnode == onode)) { if (msg_ack_required(hdr)) { struct sk_buff *skb; skb = tipc_sk_build_ack(tsk); if (skb) { msg_set_nagle_ack(buf_msg(skb)); __skb_queue_tail(xmitq, skb); } } return true; } if (!tsk_peer_msg(tsk, hdr)) return false; if (!err) return true; tipc_set_sk_state(sk, TIPC_DISCONNECTING); tipc_node_remove_conn(net, pnode, tsk->portid); sk->sk_state_change(sk); return true; default: pr_err("Unknown sk_state %u\n", sk->sk_state); } /* Abort connection setup attempt */ tipc_set_sk_state(sk, TIPC_DISCONNECTING); sk->sk_err = ECONNREFUSED; sk->sk_state_change(sk); return true; } /** * rcvbuf_limit - get proper overload limit of socket receive queue * @sk: socket * @skb: message * * For connection oriented messages, irrespective of importance, * default queue limit is 2 MB. * * For connectionless messages, queue limits are based on message * importance as follows: * * TIPC_LOW_IMPORTANCE (2 MB) * TIPC_MEDIUM_IMPORTANCE (4 MB) * TIPC_HIGH_IMPORTANCE (8 MB) * TIPC_CRITICAL_IMPORTANCE (16 MB) * * Return: overload limit according to corresponding message importance */ static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *skb) { struct tipc_sock *tsk = tipc_sk(sk); struct tipc_msg *hdr = buf_msg(skb); if (unlikely(msg_in_group(hdr))) return READ_ONCE(sk->sk_rcvbuf); if (unlikely(!msg_connected(hdr))) return READ_ONCE(sk->sk_rcvbuf) << msg_importance(hdr); if (likely(tsk->peer_caps & TIPC_BLOCK_FLOWCTL)) return READ_ONCE(sk->sk_rcvbuf); return FLOWCTL_MSG_LIM; } /** * tipc_sk_filter_rcv - validate incoming message * @sk: socket * @skb: pointer to message. * @xmitq: output message area (FIXME) * * Enqueues message on receive queue if acceptable; optionally handles * disconnect indication for a connected socket. * * Called with socket lock already taken */ static void tipc_sk_filter_rcv(struct sock *sk, struct sk_buff *skb, struct sk_buff_head *xmitq) { bool sk_conn = !tipc_sk_type_connectionless(sk); struct tipc_sock *tsk = tipc_sk(sk); struct tipc_group *grp = tsk->group; struct tipc_msg *hdr = buf_msg(skb); struct net *net = sock_net(sk); struct sk_buff_head inputq; int mtyp = msg_type(hdr); int limit, err = TIPC_OK; trace_tipc_sk_filter_rcv(sk, skb, TIPC_DUMP_ALL, " "); TIPC_SKB_CB(skb)->bytes_read = 0; __skb_queue_head_init(&inputq); __skb_queue_tail(&inputq, skb); if (unlikely(!msg_isdata(hdr))) tipc_sk_proto_rcv(sk, &inputq, xmitq); if (unlikely(grp)) tipc_group_filter_msg(grp, &inputq, xmitq); if (unlikely(!grp) && mtyp == TIPC_MCAST_MSG) tipc_mcast_filter_msg(net, &tsk->mc_method.deferredq, &inputq); /* Validate and add to receive buffer if there is space */ while ((skb = __skb_dequeue(&inputq))) { hdr = buf_msg(skb); limit = rcvbuf_limit(sk, skb); if ((sk_conn && !tipc_sk_filter_connect(tsk, skb, xmitq)) || (!sk_conn && msg_connected(hdr)) || (!grp && msg_in_group(hdr))) err = TIPC_ERR_NO_PORT; else if (sk_rmem_alloc_get(sk) + skb->truesize >= limit) { trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL, "err_overload2!"); atomic_inc(&sk->sk_drops); err = TIPC_ERR_OVERLOAD; } if (unlikely(err)) { if (tipc_msg_reverse(tipc_own_addr(net), &skb, err)) { trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_NONE, "@filter_rcv!"); __skb_queue_tail(xmitq, skb); } err = TIPC_OK; continue; } __skb_queue_tail(&sk->sk_receive_queue, skb); skb_set_owner_r(skb, sk); trace_tipc_sk_overlimit2(sk, skb, TIPC_DUMP_ALL, "rcvq >90% allocated!"); sk->sk_data_ready(sk); } } /** * tipc_sk_backlog_rcv - handle incoming message from backlog queue * @sk: socket * @skb: message * * Caller must hold socket lock */ static int tipc_sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) { unsigned int before = sk_rmem_alloc_get(sk); struct sk_buff_head xmitq; unsigned int added; __skb_queue_head_init(&xmitq); tipc_sk_filter_rcv(sk, skb, &xmitq); added = sk_rmem_alloc_get(sk) - before; atomic_add(added, &tipc_sk(sk)->dupl_rcvcnt); /* Send pending response/rejected messages, if any */ tipc_node_distr_xmit(sock_net(sk), &xmitq); return 0; } /** * tipc_sk_enqueue - extract all buffers with destination 'dport' from * inputq and try adding them to socket or backlog queue * @inputq: list of incoming buffers with potentially different destinations * @sk: socket where the buffers should be enqueued * @dport: port number for the socket * @xmitq: output queue * * Caller must hold socket lock */ static void tipc_sk_enqueue(struct sk_buff_head *inputq, struct sock *sk, u32 dport, struct sk_buff_head *xmitq) { unsigned long time_limit = jiffies + 2; struct sk_buff *skb; unsigned int lim; atomic_t *dcnt; u32 onode; while (skb_queue_len(inputq)) { if (unlikely(time_after_eq(jiffies, time_limit))) return; skb = tipc_skb_dequeue(inputq, dport); if (unlikely(!skb)) return; /* Add message directly to receive queue if possible */ if (!sock_owned_by_user(sk)) { tipc_sk_filter_rcv(sk, skb, xmitq); continue; } /* Try backlog, compensating for double-counted bytes */ dcnt = &tipc_sk(sk)->dupl_rcvcnt; if (!sk->sk_backlog.len) atomic_set(dcnt, 0); lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt); if (likely(!sk_add_backlog(sk, skb, lim))) { trace_tipc_sk_overlimit1(sk, skb, TIPC_DUMP_ALL, "bklg & rcvq >90% allocated!"); continue; } trace_tipc_sk_dump(sk, skb, TIPC_DUMP_ALL, "err_overload!"); /* Overload => reject message back to sender */ onode = tipc_own_addr(sock_net(sk)); atomic_inc(&sk->sk_drops); if (tipc_msg_reverse(onode, &skb, TIPC_ERR_OVERLOAD)) { trace_tipc_sk_rej_msg(sk, skb, TIPC_DUMP_ALL, "@sk_enqueue!"); __skb_queue_tail(xmitq, skb); } break; } } /** * tipc_sk_rcv - handle a chain of incoming buffers * @net: the associated network namespace * @inputq: buffer list containing the buffers * Consumes all buffers in list until inputq is empty * Note: may be called in multiple threads referring to the same queue */ void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq) { struct sk_buff_head xmitq; u32 dnode, dport = 0; int err; struct tipc_sock *tsk; struct sock *sk; struct sk_buff *skb; __skb_queue_head_init(&xmitq); while (skb_queue_len(inputq)) { dport = tipc_skb_peek_port(inputq, dport); tsk = tipc_sk_lookup(net, dport); if (likely(tsk)) { sk = &tsk->sk; if (likely(spin_trylock_bh(&sk->sk_lock.slock))) { tipc_sk_enqueue(inputq, sk, dport, &xmitq); spin_unlock_bh(&sk->sk_lock.slock); } /* Send pending response/rejected messages, if any */ tipc_node_distr_xmit(sock_net(sk), &xmitq); sock_put(sk); continue; } /* No destination socket => dequeue skb if still there */ skb = tipc_skb_dequeue(inputq, dport); if (!skb) return; /* Try secondary lookup if unresolved named message */ err = TIPC_ERR_NO_PORT; if (tipc_msg_lookup_dest(net, skb, &err)) goto xmit; /* Prepare for message rejection */ if (!tipc_msg_reverse(tipc_own_addr(net), &skb, err)) continue; trace_tipc_sk_rej_msg(NULL, skb, TIPC_DUMP_NONE, "@sk_rcv!"); xmit: dnode = msg_destnode(buf_msg(skb)); tipc_node_xmit_skb(net, skb, dnode, dport); } } static int tipc_wait_for_connect(struct socket *sock, long *timeo_p) { DEFINE_WAIT_FUNC(wait, woken_wake_function); struct sock *sk = sock->sk; int done; do { int err = sock_error(sk); if (err) return err; if (!*timeo_p) return -ETIMEDOUT; if (signal_pending(current)) return sock_intr_errno(*timeo_p); if (sk->sk_state == TIPC_DISCONNECTING) break; add_wait_queue(sk_sleep(sk), &wait); done = sk_wait_event(sk, timeo_p, tipc_sk_connected(sk), &wait); remove_wait_queue(sk_sleep(sk), &wait); } while (!done); return 0; } static bool tipc_sockaddr_is_sane(struct sockaddr_tipc *addr) { if (addr->family != AF_TIPC) return false; if (addr->addrtype == TIPC_SERVICE_RANGE) return (addr->addr.nameseq.lower <= addr->addr.nameseq.upper); return (addr->addrtype == TIPC_SERVICE_ADDR || addr->addrtype == TIPC_SOCKET_ADDR); } /** * tipc_connect - establish a connection to another TIPC port * @sock: socket structure * @dest: socket address for destination port * @destlen: size of socket address data structure * @flags: file-related flags associated with socket * * Return: 0 on success, errno otherwise */ static int tipc_connect(struct socket *sock, struct sockaddr *dest, int destlen, int flags) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest; struct msghdr m = {NULL,}; long timeout = (flags & O_NONBLOCK) ? 0 : tsk->conn_timeout; int previous; int res = 0; if (destlen != sizeof(struct sockaddr_tipc)) return -EINVAL; lock_sock(sk); if (tsk->group) { res = -EINVAL; goto exit; } if (dst->family == AF_UNSPEC) { memset(&tsk->peer, 0, sizeof(struct sockaddr_tipc)); if (!tipc_sk_type_connectionless(sk)) res = -EINVAL; goto exit; } if (!tipc_sockaddr_is_sane(dst)) { res = -EINVAL; goto exit; } /* DGRAM/RDM connect(), just save the destaddr */ if (tipc_sk_type_connectionless(sk)) { memcpy(&tsk->peer, dest, destlen); goto exit; } else if (dst->addrtype == TIPC_SERVICE_RANGE) { res = -EINVAL; goto exit; } previous = sk->sk_state; switch (sk->sk_state) { case TIPC_OPEN: /* Send a 'SYN-' to destination */ m.msg_name = dest; m.msg_namelen = destlen; /* If connect is in non-blocking case, set MSG_DONTWAIT to * indicate send_msg() is never blocked. */ if (!timeout) m.msg_flags = MSG_DONTWAIT; res = __tipc_sendmsg(sock, &m, 0); if ((res < 0) && (res != -EWOULDBLOCK)) goto exit; /* Just entered TIPC_CONNECTING state; the only * difference is that return value in non-blocking * case is EINPROGRESS, rather than EALREADY. */ res = -EINPROGRESS; fallthrough; case TIPC_CONNECTING: if (!timeout) { if (previous == TIPC_CONNECTING) res = -EALREADY; goto exit; } timeout = msecs_to_jiffies(timeout); /* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */ res = tipc_wait_for_connect(sock, &timeout); break; case TIPC_ESTABLISHED: res = -EISCONN; break; default: res = -EINVAL; } exit: release_sock(sk); return res; } /** * tipc_listen - allow socket to listen for incoming connections * @sock: socket structure * @len: (unused) * * Return: 0 on success, errno otherwise */ static int tipc_listen(struct socket *sock, int len) { struct sock *sk = sock->sk; int res; lock_sock(sk); res = tipc_set_sk_state(sk, TIPC_LISTEN); release_sock(sk); return res; } static int tipc_wait_for_accept(struct socket *sock, long timeo) { struct sock *sk = sock->sk; DEFINE_WAIT(wait); int err; /* True wake-one mechanism for incoming connections: only * one process gets woken up, not the 'whole herd'. * Since we do not 'race & poll' for established sockets * anymore, the common case will execute the loop only once. */ for (;;) { prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); if (timeo && skb_queue_empty(&sk->sk_receive_queue)) { release_sock(sk); timeo = schedule_timeout(timeo); lock_sock(sk); } err = 0; if (!skb_queue_empty(&sk->sk_receive_queue)) break; err = -EAGAIN; if (!timeo) break; err = sock_intr_errno(timeo); if (signal_pending(current)) break; } finish_wait(sk_sleep(sk), &wait); return err; } /** * tipc_accept - wait for connection request * @sock: listening socket * @new_sock: new socket that is to be connected * @flags: file-related flags associated with socket * @kern: caused by kernel or by userspace? * * Return: 0 on success, errno otherwise */ static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags, bool kern) { struct sock *new_sk, *sk = sock->sk; struct sk_buff *buf; struct tipc_sock *new_tsock; struct tipc_msg *msg; long timeo; int res; lock_sock(sk); if (sk->sk_state != TIPC_LISTEN) { res = -EINVAL; goto exit; } timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); res = tipc_wait_for_accept(sock, timeo); if (res) goto exit; buf = skb_peek(&sk->sk_receive_queue); res = tipc_sk_create(sock_net(sock->sk), new_sock, 0, kern); if (res) goto exit; security_sk_clone(sock->sk, new_sock->sk); new_sk = new_sock->sk; new_tsock = tipc_sk(new_sk); msg = buf_msg(buf); /* we lock on new_sk; but lockdep sees the lock on sk */ lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING); /* * Reject any stray messages received by new socket * before the socket lock was taken (very, very unlikely) */ tsk_rej_rx_queue(new_sk, TIPC_ERR_NO_PORT); /* Connect new socket to it's peer */ tipc_sk_finish_conn(new_tsock, msg_origport(msg), msg_orignode(msg)); tsk_set_importance(new_sk, msg_importance(msg)); if (msg_named(msg)) { new_tsock->conn_type = msg_nametype(msg); new_tsock->conn_instance = msg_nameinst(msg); } /* * Respond to 'SYN-' by discarding it & returning 'ACK'-. * Respond to 'SYN+' by queuing it on new socket. */ if (!msg_data_sz(msg)) { struct msghdr m = {NULL,}; tsk_advance_rx_queue(sk); __tipc_sendstream(new_sock, &m, 0); } else { __skb_dequeue(&sk->sk_receive_queue); __skb_queue_head(&new_sk->sk_receive_queue, buf); skb_set_owner_r(buf, new_sk); } release_sock(new_sk); exit: release_sock(sk); return res; } /** * tipc_shutdown - shutdown socket connection * @sock: socket structure * @how: direction to close (must be SHUT_RDWR) * * Terminates connection (if necessary), then purges socket's receive queue. * * Return: 0 on success, errno otherwise */ static int tipc_shutdown(struct socket *sock, int how) { struct sock *sk = sock->sk; int res; if (how != SHUT_RDWR) return -EINVAL; lock_sock(sk); trace_tipc_sk_shutdown(sk, NULL, TIPC_DUMP_ALL, " "); __tipc_shutdown(sock, TIPC_CONN_SHUTDOWN); sk->sk_shutdown = SHUTDOWN_MASK; if (sk->sk_state == TIPC_DISCONNECTING) { /* Discard any unreceived messages */ __skb_queue_purge(&sk->sk_receive_queue); res = 0; } else { res = -ENOTCONN; } /* Wake up anyone sleeping in poll. */ sk->sk_state_change(sk); release_sock(sk); return res; } static void tipc_sk_check_probing_state(struct sock *sk, struct sk_buff_head *list) { struct tipc_sock *tsk = tipc_sk(sk); u32 pnode = tsk_peer_node(tsk); u32 pport = tsk_peer_port(tsk); u32 self = tsk_own_node(tsk); u32 oport = tsk->portid; struct sk_buff *skb; if (tsk->probe_unacked) { tipc_set_sk_state(sk, TIPC_DISCONNECTING); sk->sk_err = ECONNABORTED; tipc_node_remove_conn(sock_net(sk), pnode, pport); sk->sk_state_change(sk); return; } /* Prepare new probe */ skb = tipc_msg_create(CONN_MANAGER, CONN_PROBE, INT_H_SIZE, 0, pnode, self, pport, oport, TIPC_OK); if (skb) __skb_queue_tail(list, skb); tsk->probe_unacked = true; sk_reset_timer(sk, &sk->sk_timer, jiffies + CONN_PROBING_INTV); } static void tipc_sk_retry_connect(struct sock *sk, struct sk_buff_head *list) { struct tipc_sock *tsk = tipc_sk(sk); /* Try again later if dest link is congested */ if (tsk->cong_link_cnt) { sk_reset_timer(sk, &sk->sk_timer, msecs_to_jiffies(100)); return; } /* Prepare SYN for retransmit */ tipc_msg_skb_clone(&sk->sk_write_queue, list); } static void tipc_sk_timeout(struct timer_list *t) { struct sock *sk = from_timer(sk, t, sk_timer); struct tipc_sock *tsk = tipc_sk(sk); u32 pnode = tsk_peer_node(tsk); struct sk_buff_head list; int rc = 0; __skb_queue_head_init(&list); bh_lock_sock(sk); /* Try again later if socket is busy */ if (sock_owned_by_user(sk)) { sk_reset_timer(sk, &sk->sk_timer, jiffies + HZ / 20); bh_unlock_sock(sk); sock_put(sk); return; } if (sk->sk_state == TIPC_ESTABLISHED) tipc_sk_check_probing_state(sk, &list); else if (sk->sk_state == TIPC_CONNECTING) tipc_sk_retry_connect(sk, &list); bh_unlock_sock(sk); if (!skb_queue_empty(&list)) rc = tipc_node_xmit(sock_net(sk), &list, pnode, tsk->portid); /* SYN messages may cause link congestion */ if (rc == -ELINKCONG) { tipc_dest_push(&tsk->cong_links, pnode, 0); tsk->cong_link_cnt = 1; } sock_put(sk); } static int tipc_sk_publish(struct tipc_sock *tsk, struct tipc_uaddr *ua) { struct sock *sk = &tsk->sk; struct net *net = sock_net(sk); struct tipc_socket_addr skaddr; struct publication *p; u32 key; if (tipc_sk_connected(sk)) return -EINVAL; key = tsk->portid + tsk->pub_count + 1; if (key == tsk->portid) return -EADDRINUSE; skaddr.ref = tsk->portid; skaddr.node = tipc_own_addr(net); p = tipc_nametbl_publish(net, ua, &skaddr, key); if (unlikely(!p)) return -EINVAL; list_add(&p->binding_sock, &tsk->publications); tsk->pub_count++; tsk->published = true; return 0; } static int tipc_sk_withdraw(struct tipc_sock *tsk, struct tipc_uaddr *ua) { struct net *net = sock_net(&tsk->sk); struct publication *safe, *p; struct tipc_uaddr _ua; int rc = -EINVAL; list_for_each_entry_safe(p, safe, &tsk->publications, binding_sock) { if (!ua) { tipc_uaddr(&_ua, TIPC_SERVICE_RANGE, p->scope, p->sr.type, p->sr.lower, p->sr.upper); tipc_nametbl_withdraw(net, &_ua, &p->sk, p->key); continue; } /* Unbind specific publication */ if (p->scope != ua->scope) continue; if (p->sr.type != ua->sr.type) continue; if (p->sr.lower != ua->sr.lower) continue; if (p->sr.upper != ua->sr.upper) break; tipc_nametbl_withdraw(net, ua, &p->sk, p->key); rc = 0; break; } if (list_empty(&tsk->publications)) { tsk->published = 0; rc = 0; } return rc; } /* tipc_sk_reinit: set non-zero address in all existing sockets * when we go from standalone to network mode. */ void tipc_sk_reinit(struct net *net) { struct tipc_net *tn = net_generic(net, tipc_net_id); struct rhashtable_iter iter; struct tipc_sock *tsk; struct tipc_msg *msg; rhashtable_walk_enter(&tn->sk_rht, &iter); do { rhashtable_walk_start(&iter); while ((tsk = rhashtable_walk_next(&iter)) && !IS_ERR(tsk)) { sock_hold(&tsk->sk); rhashtable_walk_stop(&iter); lock_sock(&tsk->sk); msg = &tsk->phdr; msg_set_prevnode(msg, tipc_own_addr(net)); msg_set_orignode(msg, tipc_own_addr(net)); release_sock(&tsk->sk); rhashtable_walk_start(&iter); sock_put(&tsk->sk); } rhashtable_walk_stop(&iter); } while (tsk == ERR_PTR(-EAGAIN)); rhashtable_walk_exit(&iter); } static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid) { struct tipc_net *tn = net_generic(net, tipc_net_id); struct tipc_sock *tsk; rcu_read_lock(); tsk = rhashtable_lookup(&tn->sk_rht, &portid, tsk_rht_params); if (tsk) sock_hold(&tsk->sk); rcu_read_unlock(); return tsk; } static int tipc_sk_insert(struct tipc_sock *tsk) { struct sock *sk = &tsk->sk; struct net *net = sock_net(sk); struct tipc_net *tn = net_generic(net, tipc_net_id); u32 remaining = (TIPC_MAX_PORT - TIPC_MIN_PORT) + 1; u32 portid = prandom_u32() % remaining + TIPC_MIN_PORT; while (remaining--) { portid++; if ((portid < TIPC_MIN_PORT) || (portid > TIPC_MAX_PORT)) portid = TIPC_MIN_PORT; tsk->portid = portid; sock_hold(&tsk->sk); if (!rhashtable_lookup_insert_fast(&tn->sk_rht, &tsk->node, tsk_rht_params)) return 0; sock_put(&tsk->sk); } return -1; } static void tipc_sk_remove(struct tipc_sock *tsk) { struct sock *sk = &tsk->sk; struct tipc_net *tn = net_generic(sock_net(sk), tipc_net_id); if (!rhashtable_remove_fast(&tn->sk_rht, &tsk->node, tsk_rht_params)) { WARN_ON(refcount_read(&sk->sk_refcnt) == 1); __sock_put(sk); } } static const struct rhashtable_params tsk_rht_params = { .nelem_hint = 192, .head_offset = offsetof(struct tipc_sock, node), .key_offset = offsetof(struct tipc_sock, portid), .key_len = sizeof(u32), /* portid */ .max_size = 1048576, .min_size = 256, .automatic_shrinking = true, }; int tipc_sk_rht_init(struct net *net) { struct tipc_net *tn = net_generic(net, tipc_net_id); return rhashtable_init(&tn->sk_rht, &tsk_rht_params); } void tipc_sk_rht_destroy(struct net *net) { struct tipc_net *tn = net_generic(net, tipc_net_id); /* Wait for socket readers to complete */ synchronize_net(); rhashtable_destroy(&tn->sk_rht); } static int tipc_sk_join(struct tipc_sock *tsk, struct tipc_group_req *mreq) { struct net *net = sock_net(&tsk->sk); struct tipc_group *grp = tsk->group; struct tipc_msg *hdr = &tsk->phdr; struct tipc_uaddr ua; int rc; if (mreq->type < TIPC_RESERVED_TYPES) return -EACCES; if (mreq->scope > TIPC_NODE_SCOPE) return -EINVAL; if (mreq->scope != TIPC_NODE_SCOPE) mreq->scope = TIPC_CLUSTER_SCOPE; if (grp) return -EACCES; grp = tipc_group_create(net, tsk->portid, mreq, &tsk->group_is_open); if (!grp) return -ENOMEM; tsk->group = grp; msg_set_lookup_scope(hdr, mreq->scope); msg_set_nametype(hdr, mreq->type); msg_set_dest_droppable(hdr, true); tipc_nametbl_build_group(net, grp, mreq->type, mreq->scope); tipc_uaddr(&ua, TIPC_SERVICE_RANGE, mreq->scope, mreq->type, mreq->instance, mreq->instance); rc = tipc_sk_publish(tsk, &ua); if (rc) { tipc_group_delete(net, grp); tsk->group = NULL; return rc; } /* Eliminate any risk that a broadcast overtakes sent JOINs */ tsk->mc_method.rcast = true; tsk->mc_method.mandatory = true; tipc_group_join(net, grp, &tsk->sk.sk_rcvbuf); return rc; } static int tipc_sk_leave(struct tipc_sock *tsk) { struct net *net = sock_net(&tsk->sk); struct tipc_group *grp = tsk->group; struct tipc_uaddr ua; int scope; if (!grp) return -EINVAL; ua.addrtype = TIPC_SERVICE_RANGE; tipc_group_self(grp, &ua.sr, &scope); ua.scope = scope; tipc_group_delete(net, grp); tsk->group = NULL; tipc_sk_withdraw(tsk, &ua); return 0; } /** * tipc_setsockopt - set socket option * @sock: socket structure * @lvl: option level * @opt: option identifier * @ov: pointer to new option value * @ol: length of option value * * For stream sockets only, accepts and ignores all IPPROTO_TCP options * (to ease compatibility). * * Return: 0 on success, errno otherwise */ static int tipc_setsockopt(struct socket *sock, int lvl, int opt, sockptr_t ov, unsigned int ol) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_group_req mreq; u32 value = 0; int res = 0; if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM)) return 0; if (lvl != SOL_TIPC) return -ENOPROTOOPT; switch (opt) { case TIPC_IMPORTANCE: case TIPC_SRC_DROPPABLE: case TIPC_DEST_DROPPABLE: case TIPC_CONN_TIMEOUT: case TIPC_NODELAY: if (ol < sizeof(value)) return -EINVAL; if (copy_from_sockptr(&value, ov, sizeof(u32))) return -EFAULT; break; case TIPC_GROUP_JOIN: if (ol < sizeof(mreq)) return -EINVAL; if (copy_from_sockptr(&mreq, ov, sizeof(mreq))) return -EFAULT; break; default: if (!sockptr_is_null(ov) || ol) return -EINVAL; } lock_sock(sk); switch (opt) { case TIPC_IMPORTANCE: res = tsk_set_importance(sk, value); break; case TIPC_SRC_DROPPABLE: if (sock->type != SOCK_STREAM) tsk_set_unreliable(tsk, value); else res = -ENOPROTOOPT; break; case TIPC_DEST_DROPPABLE: tsk_set_unreturnable(tsk, value); break; case TIPC_CONN_TIMEOUT: tipc_sk(sk)->conn_timeout = value; break; case TIPC_MCAST_BROADCAST: tsk->mc_method.rcast = false; tsk->mc_method.mandatory = true; break; case TIPC_MCAST_REPLICAST: tsk->mc_method.rcast = true; tsk->mc_method.mandatory = true; break; case TIPC_GROUP_JOIN: res = tipc_sk_join(tsk, &mreq); break; case TIPC_GROUP_LEAVE: res = tipc_sk_leave(tsk); break; case TIPC_NODELAY: tsk->nodelay = !!value; tsk_set_nagle(tsk); break; default: res = -EINVAL; } release_sock(sk); return res; } /** * tipc_getsockopt - get socket option * @sock: socket structure * @lvl: option level * @opt: option identifier * @ov: receptacle for option value * @ol: receptacle for length of option value * * For stream sockets only, returns 0 length result for all IPPROTO_TCP options * (to ease compatibility). * * Return: 0 on success, errno otherwise */ static int tipc_getsockopt(struct socket *sock, int lvl, int opt, char __user *ov, int __user *ol) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_service_range seq; int len, scope; u32 value; int res; if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM)) return put_user(0, ol); if (lvl != SOL_TIPC) return -ENOPROTOOPT; res = get_user(len, ol); if (res) return res; lock_sock(sk); switch (opt) { case TIPC_IMPORTANCE: value = tsk_importance(tsk); break; case TIPC_SRC_DROPPABLE: value = tsk_unreliable(tsk); break; case TIPC_DEST_DROPPABLE: value = tsk_unreturnable(tsk); break; case TIPC_CONN_TIMEOUT: value = tsk->conn_timeout; /* no need to set "res", since already 0 at this point */ break; case TIPC_NODE_RECVQ_DEPTH: value = 0; /* was tipc_queue_size, now obsolete */ break; case TIPC_SOCK_RECVQ_DEPTH: value = skb_queue_len(&sk->sk_receive_queue); break; case TIPC_SOCK_RECVQ_USED: value = sk_rmem_alloc_get(sk); break; case TIPC_GROUP_JOIN: seq.type = 0; if (tsk->group) tipc_group_self(tsk->group, &seq, &scope); value = seq.type; break; default: res = -EINVAL; } release_sock(sk); if (res) return res; /* "get" failed */ if (len < sizeof(value)) return -EINVAL; if (copy_to_user(ov, &value, sizeof(value))) return -EFAULT; return put_user(sizeof(value), ol); } static int tipc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) { struct net *net = sock_net(sock->sk); struct tipc_sioc_nodeid_req nr = {0}; struct tipc_sioc_ln_req lnr; void __user *argp = (void __user *)arg; switch (cmd) { case SIOCGETLINKNAME: if (copy_from_user(&lnr, argp, sizeof(lnr))) return -EFAULT; if (!tipc_node_get_linkname(net, lnr.bearer_id & 0xffff, lnr.peer, lnr.linkname, TIPC_MAX_LINK_NAME)) { if (copy_to_user(argp, &lnr, sizeof(lnr))) return -EFAULT; return 0; } return -EADDRNOTAVAIL; case SIOCGETNODEID: if (copy_from_user(&nr, argp, sizeof(nr))) return -EFAULT; if (!tipc_node_get_id(net, nr.peer, nr.node_id)) return -EADDRNOTAVAIL; if (copy_to_user(argp, &nr, sizeof(nr))) return -EFAULT; return 0; default: return -ENOIOCTLCMD; } } static int tipc_socketpair(struct socket *sock1, struct socket *sock2) { struct tipc_sock *tsk2 = tipc_sk(sock2->sk); struct tipc_sock *tsk1 = tipc_sk(sock1->sk); u32 onode = tipc_own_addr(sock_net(sock1->sk)); tsk1->peer.family = AF_TIPC; tsk1->peer.addrtype = TIPC_SOCKET_ADDR; tsk1->peer.scope = TIPC_NODE_SCOPE; tsk1->peer.addr.id.ref = tsk2->portid; tsk1->peer.addr.id.node = onode; tsk2->peer.family = AF_TIPC; tsk2->peer.addrtype = TIPC_SOCKET_ADDR; tsk2->peer.scope = TIPC_NODE_SCOPE; tsk2->peer.addr.id.ref = tsk1->portid; tsk2->peer.addr.id.node = onode; tipc_sk_finish_conn(tsk1, tsk2->portid, onode); tipc_sk_finish_conn(tsk2, tsk1->portid, onode); return 0; } /* Protocol switches for the various types of TIPC sockets */ static const struct proto_ops msg_ops = { .owner = THIS_MODULE, .family = AF_TIPC, .release = tipc_release, .bind = tipc_bind, .connect = tipc_connect, .socketpair = tipc_socketpair, .accept = sock_no_accept, .getname = tipc_getname, .poll = tipc_poll, .ioctl = tipc_ioctl, .listen = sock_no_listen, .shutdown = tipc_shutdown, .setsockopt = tipc_setsockopt, .getsockopt = tipc_getsockopt, .sendmsg = tipc_sendmsg, .recvmsg = tipc_recvmsg, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage }; static const struct proto_ops packet_ops = { .owner = THIS_MODULE, .family = AF_TIPC, .release = tipc_release, .bind = tipc_bind, .connect = tipc_connect, .socketpair = tipc_socketpair, .accept = tipc_accept, .getname = tipc_getname, .poll = tipc_poll, .ioctl = tipc_ioctl, .listen = tipc_listen, .shutdown = tipc_shutdown, .setsockopt = tipc_setsockopt, .getsockopt = tipc_getsockopt, .sendmsg = tipc_send_packet, .recvmsg = tipc_recvmsg, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage }; static const struct proto_ops stream_ops = { .owner = THIS_MODULE, .family = AF_TIPC, .release = tipc_release, .bind = tipc_bind, .connect = tipc_connect, .socketpair = tipc_socketpair, .accept = tipc_accept, .getname = tipc_getname, .poll = tipc_poll, .ioctl = tipc_ioctl, .listen = tipc_listen, .shutdown = tipc_shutdown, .setsockopt = tipc_setsockopt, .getsockopt = tipc_getsockopt, .sendmsg = tipc_sendstream, .recvmsg = tipc_recvstream, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage }; static const struct net_proto_family tipc_family_ops = { .owner = THIS_MODULE, .family = AF_TIPC, .create = tipc_sk_create }; static struct proto tipc_proto = { .name = "TIPC", .owner = THIS_MODULE, .obj_size = sizeof(struct tipc_sock), .sysctl_rmem = sysctl_tipc_rmem }; /** * tipc_socket_init - initialize TIPC socket interface * * Return: 0 on success, errno otherwise */ int tipc_socket_init(void) { int res; res = proto_register(&tipc_proto, 1); if (res) { pr_err("Failed to register TIPC protocol type\n"); goto out; } res = sock_register(&tipc_family_ops); if (res) { pr_err("Failed to register TIPC socket type\n"); proto_unregister(&tipc_proto); goto out; } out: return res; } /** * tipc_socket_stop - stop TIPC socket interface */ void tipc_socket_stop(void) { sock_unregister(tipc_family_ops.family); proto_unregister(&tipc_proto); } /* Caller should hold socket lock for the passed tipc socket. */ static int __tipc_nl_add_sk_con(struct sk_buff *skb, struct tipc_sock *tsk) { u32 peer_node; u32 peer_port; struct nlattr *nest; peer_node = tsk_peer_node(tsk); peer_port = tsk_peer_port(tsk); nest = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_CON); if (!nest) return -EMSGSIZE; if (nla_put_u32(skb, TIPC_NLA_CON_NODE, peer_node)) goto msg_full; if (nla_put_u32(skb, TIPC_NLA_CON_SOCK, peer_port)) goto msg_full; if (tsk->conn_type != 0) { if (nla_put_flag(skb, TIPC_NLA_CON_FLAG)) goto msg_full; if (nla_put_u32(skb, TIPC_NLA_CON_TYPE, tsk->conn_type)) goto msg_full; if (nla_put_u32(skb, TIPC_NLA_CON_INST, tsk->conn_instance)) goto msg_full; } nla_nest_end(skb, nest); return 0; msg_full: nla_nest_cancel(skb, nest); return -EMSGSIZE; } static int __tipc_nl_add_sk_info(struct sk_buff *skb, struct tipc_sock *tsk) { struct net *net = sock_net(skb->sk); struct sock *sk = &tsk->sk; if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid) || nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tipc_own_addr(net))) return -EMSGSIZE; if (tipc_sk_connected(sk)) { if (__tipc_nl_add_sk_con(skb, tsk)) return -EMSGSIZE; } else if (!list_empty(&tsk->publications)) { if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL)) return -EMSGSIZE; } return 0; } /* Caller should hold socket lock for the passed tipc socket. */ static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb, struct tipc_sock *tsk) { struct nlattr *attrs; void *hdr; hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, &tipc_genl_family, NLM_F_MULTI, TIPC_NL_SOCK_GET); if (!hdr) goto msg_cancel; attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK); if (!attrs) goto genlmsg_cancel; if (__tipc_nl_add_sk_info(skb, tsk)) goto attr_msg_cancel; nla_nest_end(skb, attrs); genlmsg_end(skb, hdr); return 0; attr_msg_cancel: nla_nest_cancel(skb, attrs); genlmsg_cancel: genlmsg_cancel(skb, hdr); msg_cancel: return -EMSGSIZE; } int tipc_nl_sk_walk(struct sk_buff *skb, struct netlink_callback *cb, int (*skb_handler)(struct sk_buff *skb, struct netlink_callback *cb, struct tipc_sock *tsk)) { struct rhashtable_iter *iter = (void *)cb->args[4]; struct tipc_sock *tsk; int err; rhashtable_walk_start(iter); while ((tsk = rhashtable_walk_next(iter)) != NULL) { if (IS_ERR(tsk)) { err = PTR_ERR(tsk); if (err == -EAGAIN) { err = 0; continue; } break; } sock_hold(&tsk->sk); rhashtable_walk_stop(iter); lock_sock(&tsk->sk); err = skb_handler(skb, cb, tsk); if (err) { release_sock(&tsk->sk); sock_put(&tsk->sk); goto out; } release_sock(&tsk->sk); rhashtable_walk_start(iter); sock_put(&tsk->sk); } rhashtable_walk_stop(iter); out: return skb->len; } EXPORT_SYMBOL(tipc_nl_sk_walk); int tipc_dump_start(struct netlink_callback *cb) { return __tipc_dump_start(cb, sock_net(cb->skb->sk)); } EXPORT_SYMBOL(tipc_dump_start); int __tipc_dump_start(struct netlink_callback *cb, struct net *net) { /* tipc_nl_name_table_dump() uses cb->args[0...3]. */ struct rhashtable_iter *iter = (void *)cb->args[4]; struct tipc_net *tn = tipc_net(net); if (!iter) { iter = kmalloc(sizeof(*iter), GFP_KERNEL); if (!iter) return -ENOMEM; cb->args[4] = (long)iter; } rhashtable_walk_enter(&tn->sk_rht, iter); return 0; } int tipc_dump_done(struct netlink_callback *cb) { struct rhashtable_iter *hti = (void *)cb->args[4]; rhashtable_walk_exit(hti); kfree(hti); return 0; } EXPORT_SYMBOL(tipc_dump_done); int tipc_sk_fill_sock_diag(struct sk_buff *skb, struct netlink_callback *cb, struct tipc_sock *tsk, u32 sk_filter_state, u64 (*tipc_diag_gen_cookie)(struct sock *sk)) { struct sock *sk = &tsk->sk; struct nlattr *attrs; struct nlattr *stat; /*filter response w.r.t sk_state*/ if (!(sk_filter_state & (1 << sk->sk_state))) return 0; attrs = nla_nest_start_noflag(skb, TIPC_NLA_SOCK); if (!attrs) goto msg_cancel; if (__tipc_nl_add_sk_info(skb, tsk)) goto attr_msg_cancel; if (nla_put_u32(skb, TIPC_NLA_SOCK_TYPE, (u32)sk->sk_type) || nla_put_u32(skb, TIPC_NLA_SOCK_TIPC_STATE, (u32)sk->sk_state) || nla_put_u32(skb, TIPC_NLA_SOCK_INO, sock_i_ino(sk)) || nla_put_u32(skb, TIPC_NLA_SOCK_UID, from_kuid_munged(sk_user_ns(NETLINK_CB(cb->skb).sk), sock_i_uid(sk))) || nla_put_u64_64bit(skb, TIPC_NLA_SOCK_COOKIE, tipc_diag_gen_cookie(sk), TIPC_NLA_SOCK_PAD)) goto attr_msg_cancel; stat = nla_nest_start_noflag(skb, TIPC_NLA_SOCK_STAT); if (!stat) goto attr_msg_cancel; if (nla_put_u32(skb, TIPC_NLA_SOCK_STAT_RCVQ, skb_queue_len(&sk->sk_receive_queue)) || nla_put_u32(skb, TIPC_NLA_SOCK_STAT_SENDQ, skb_queue_len(&sk->sk_write_queue)) || nla_put_u32(skb, TIPC_NLA_SOCK_STAT_DROP, atomic_read(&sk->sk_drops))) goto stat_msg_cancel; if (tsk->cong_link_cnt && nla_put_flag(skb, TIPC_NLA_SOCK_STAT_LINK_CONG)) goto stat_msg_cancel; if (tsk_conn_cong(tsk) && nla_put_flag(skb, TIPC_NLA_SOCK_STAT_CONN_CONG)) goto stat_msg_cancel; nla_nest_end(skb, stat); if (tsk->group) if (tipc_group_fill_sock_diag(tsk->group, skb)) goto stat_msg_cancel; nla_nest_end(skb, attrs); return 0; stat_msg_cancel: nla_nest_cancel(skb, stat); attr_msg_cancel: nla_nest_cancel(skb, attrs); msg_cancel: return -EMSGSIZE; } EXPORT_SYMBOL(tipc_sk_fill_sock_diag); int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb) { return tipc_nl_sk_walk(skb, cb, __tipc_nl_add_sk); } /* Caller should hold socket lock for the passed tipc socket. */ static int __tipc_nl_add_sk_publ(struct sk_buff *skb, struct netlink_callback *cb, struct publication *publ) { void *hdr; struct nlattr *attrs; hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, &tipc_genl_family, NLM_F_MULTI, TIPC_NL_PUBL_GET); if (!hdr) goto msg_cancel; attrs = nla_nest_start_noflag(skb, TIPC_NLA_PUBL); if (!attrs) goto genlmsg_cancel; if (nla_put_u32(skb, TIPC_NLA_PUBL_KEY, publ->key)) goto attr_msg_cancel; if (nla_put_u32(skb, TIPC_NLA_PUBL_TYPE, publ->sr.type)) goto attr_msg_cancel; if (nla_put_u32(skb, TIPC_NLA_PUBL_LOWER, publ->sr.lower)) goto attr_msg_cancel; if (nla_put_u32(skb, TIPC_NLA_PUBL_UPPER, publ->sr.upper)) goto attr_msg_cancel; nla_nest_end(skb, attrs); genlmsg_end(skb, hdr); return 0; attr_msg_cancel: nla_nest_cancel(skb, attrs); genlmsg_cancel: genlmsg_cancel(skb, hdr); msg_cancel: return -EMSGSIZE; } /* Caller should hold socket lock for the passed tipc socket. */ static int __tipc_nl_list_sk_publ(struct sk_buff *skb, struct netlink_callback *cb, struct tipc_sock *tsk, u32 *last_publ) { int err; struct publication *p; if (*last_publ) { list_for_each_entry(p, &tsk->publications, binding_sock) { if (p->key == *last_publ) break; } if (p->key != *last_publ) { /* We never set seq or call nl_dump_check_consistent() * this means that setting prev_seq here will cause the * consistence check to fail in the netlink callback * handler. Resulting in the last NLMSG_DONE message * having the NLM_F_DUMP_INTR flag set. */ cb->prev_seq = 1; *last_publ = 0; return -EPIPE; } } else { p = list_first_entry(&tsk->publications, struct publication, binding_sock); } list_for_each_entry_from(p, &tsk->publications, binding_sock) { err = __tipc_nl_add_sk_publ(skb, cb, p); if (err) { *last_publ = p->key; return err; } } *last_publ = 0; return 0; } int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb) { int err; u32 tsk_portid = cb->args[0]; u32 last_publ = cb->args[1]; u32 done = cb->args[2]; struct net *net = sock_net(skb->sk); struct tipc_sock *tsk; if (!tsk_portid) { struct nlattr **attrs = genl_dumpit_info(cb)->attrs; struct nlattr *sock[TIPC_NLA_SOCK_MAX + 1]; if (!attrs[TIPC_NLA_SOCK]) return -EINVAL; err = nla_parse_nested_deprecated(sock, TIPC_NLA_SOCK_MAX, attrs[TIPC_NLA_SOCK], tipc_nl_sock_policy, NULL); if (err) return err; if (!sock[TIPC_NLA_SOCK_REF]) return -EINVAL; tsk_portid = nla_get_u32(sock[TIPC_NLA_SOCK_REF]); } if (done) return 0; tsk = tipc_sk_lookup(net, tsk_portid); if (!tsk) return -EINVAL; lock_sock(&tsk->sk); err = __tipc_nl_list_sk_publ(skb, cb, tsk, &last_publ); if (!err) done = 1; release_sock(&tsk->sk); sock_put(&tsk->sk); cb->args[0] = tsk_portid; cb->args[1] = last_publ; cb->args[2] = done; return skb->len; } /** * tipc_sk_filtering - check if a socket should be traced * @sk: the socket to be examined * * @sysctl_tipc_sk_filter is used as the socket tuple for filtering: * (portid, sock type, name type, name lower, name upper) * * Return: true if the socket meets the socket tuple data * (value 0 = 'any') or when there is no tuple set (all = 0), * otherwise false */ bool tipc_sk_filtering(struct sock *sk) { struct tipc_sock *tsk; struct publication *p; u32 _port, _sktype, _type, _lower, _upper; u32 type = 0, lower = 0, upper = 0; if (!sk) return true; tsk = tipc_sk(sk); _port = sysctl_tipc_sk_filter[0]; _sktype = sysctl_tipc_sk_filter[1]; _type = sysctl_tipc_sk_filter[2]; _lower = sysctl_tipc_sk_filter[3]; _upper = sysctl_tipc_sk_filter[4]; if (!_port && !_sktype && !_type && !_lower && !_upper) return true; if (_port) return (_port == tsk->portid); if (_sktype && _sktype != sk->sk_type) return false; if (tsk->published) { p = list_first_entry_or_null(&tsk->publications, struct publication, binding_sock); if (p) { type = p->sr.type; lower = p->sr.lower; upper = p->sr.upper; } } if (!tipc_sk_type_connectionless(sk)) { type = tsk->conn_type; lower = tsk->conn_instance; upper = tsk->conn_instance; } if ((_type && _type != type) || (_lower && _lower != lower) || (_upper && _upper != upper)) return false; return true; } u32 tipc_sock_get_portid(struct sock *sk) { return (sk) ? (tipc_sk(sk))->portid : 0; } /** * tipc_sk_overlimit1 - check if socket rx queue is about to be overloaded, * both the rcv and backlog queues are considered * @sk: tipc sk to be checked * @skb: tipc msg to be checked * * Return: true if the socket rx queue allocation is > 90%, otherwise false */ bool tipc_sk_overlimit1(struct sock *sk, struct sk_buff *skb) { atomic_t *dcnt = &tipc_sk(sk)->dupl_rcvcnt; unsigned int lim = rcvbuf_limit(sk, skb) + atomic_read(dcnt); unsigned int qsize = sk->sk_backlog.len + sk_rmem_alloc_get(sk); return (qsize > lim * 90 / 100); } /** * tipc_sk_overlimit2 - check if socket rx queue is about to be overloaded, * only the rcv queue is considered * @sk: tipc sk to be checked * @skb: tipc msg to be checked * * Return: true if the socket rx queue allocation is > 90%, otherwise false */ bool tipc_sk_overlimit2(struct sock *sk, struct sk_buff *skb) { unsigned int lim = rcvbuf_limit(sk, skb); unsigned int qsize = sk_rmem_alloc_get(sk); return (qsize > lim * 90 / 100); } /** * tipc_sk_dump - dump TIPC socket * @sk: tipc sk to be dumped * @dqueues: bitmask to decide if any socket queue to be dumped? * - TIPC_DUMP_NONE: don't dump socket queues * - TIPC_DUMP_SK_SNDQ: dump socket send queue * - TIPC_DUMP_SK_RCVQ: dump socket rcv queue * - TIPC_DUMP_SK_BKLGQ: dump socket backlog queue * - TIPC_DUMP_ALL: dump all the socket queues above * @buf: returned buffer of dump data in format */ int tipc_sk_dump(struct sock *sk, u16 dqueues, char *buf) { int i = 0; size_t sz = (dqueues) ? SK_LMAX : SK_LMIN; struct tipc_sock *tsk; struct publication *p; bool tsk_connected; if (!sk) { i += scnprintf(buf, sz, "sk data: (null)\n"); return i; } tsk = tipc_sk(sk); tsk_connected = !tipc_sk_type_connectionless(sk); i += scnprintf(buf, sz, "sk data: %u", sk->sk_type); i += scnprintf(buf + i, sz - i, " %d", sk->sk_state); i += scnprintf(buf + i, sz - i, " %x", tsk_own_node(tsk)); i += scnprintf(buf + i, sz - i, " %u", tsk->portid); i += scnprintf(buf + i, sz - i, " | %u", tsk_connected); if (tsk_connected) { i += scnprintf(buf + i, sz - i, " %x", tsk_peer_node(tsk)); i += scnprintf(buf + i, sz - i, " %u", tsk_peer_port(tsk)); i += scnprintf(buf + i, sz - i, " %u", tsk->conn_type); i += scnprintf(buf + i, sz - i, " %u", tsk->conn_instance); } i += scnprintf(buf + i, sz - i, " | %u", tsk->published); if (tsk->published) { p = list_first_entry_or_null(&tsk->publications, struct publication, binding_sock); i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.type : 0); i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.lower : 0); i += scnprintf(buf + i, sz - i, " %u", (p) ? p->sr.upper : 0); } i += scnprintf(buf + i, sz - i, " | %u", tsk->snd_win); i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_win); i += scnprintf(buf + i, sz - i, " %u", tsk->max_pkt); i += scnprintf(buf + i, sz - i, " %x", tsk->peer_caps); i += scnprintf(buf + i, sz - i, " %u", tsk->cong_link_cnt); i += scnprintf(buf + i, sz - i, " %u", tsk->snt_unacked); i += scnprintf(buf + i, sz - i, " %u", tsk->rcv_unacked); i += scnprintf(buf + i, sz - i, " %u", atomic_read(&tsk->dupl_rcvcnt)); i += scnprintf(buf + i, sz - i, " %u", sk->sk_shutdown); i += scnprintf(buf + i, sz - i, " | %d", sk_wmem_alloc_get(sk)); i += scnprintf(buf + i, sz - i, " %d", sk->sk_sndbuf); i += scnprintf(buf + i, sz - i, " | %d", sk_rmem_alloc_get(sk)); i += scnprintf(buf + i, sz - i, " %d", sk->sk_rcvbuf); i += scnprintf(buf + i, sz - i, " | %d\n", READ_ONCE(sk->sk_backlog.len)); if (dqueues & TIPC_DUMP_SK_SNDQ) { i += scnprintf(buf + i, sz - i, "sk_write_queue: "); i += tipc_list_dump(&sk->sk_write_queue, false, buf + i); } if (dqueues & TIPC_DUMP_SK_RCVQ) { i += scnprintf(buf + i, sz - i, "sk_receive_queue: "); i += tipc_list_dump(&sk->sk_receive_queue, false, buf + i); } if (dqueues & TIPC_DUMP_SK_BKLGQ) { i += scnprintf(buf + i, sz - i, "sk_backlog:\n head "); i += tipc_skb_dump(sk->sk_backlog.head, false, buf + i); if (sk->sk_backlog.tail != sk->sk_backlog.head) { i += scnprintf(buf + i, sz - i, " tail "); i += tipc_skb_dump(sk->sk_backlog.tail, false, buf + i); } } return i; }