/* * net/tipc/socket.c: TIPC socket API * * Copyright (c) 2001-2007, 2012-2014, Ericsson AB * Copyright (c) 2004-2008, 2010-2013, Wind River Systems * 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 "core.h" #include "port.h" #include "name_table.h" #include "node.h" #include "link.h" #include #define SS_LISTENING -1 /* socket is listening */ #define SS_READY -2 /* socket is connectionless */ #define CONN_TIMEOUT_DEFAULT 8000 /* default connect timeout = 8s */ #define TIPC_FWD_MSG 1 static int tipc_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 int tipc_release(struct socket *sock); static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags); static int tipc_wait_for_sndmsg(struct socket *sock, long *timeo_p); 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 struct proto tipc_proto_kern; /* * Revised TIPC socket locking policy: * * Most socket operations take the standard socket lock when they start * and hold it until they finish (or until they need to sleep). Acquiring * this lock grants the owner exclusive access to the fields of the socket * data structures, with the exception of the backlog queue. A few socket * operations can be done without taking the socket lock because they only * read socket information that never changes during the life of the socket. * * Socket operations may acquire the lock for the associated TIPC port if they * need to perform an operation on the port. If any routine needs to acquire * both the socket lock and the port lock it must take the socket lock first * to avoid the risk of deadlock. * * The dispatcher handling incoming messages cannot grab the socket lock in * the standard fashion, since invoked it runs at the BH level and cannot block. * Instead, it checks to see if the socket lock is currently owned by someone, * and either handles the message itself or adds it to the socket's backlog * queue; in the latter case the queued message is processed once the process * owning the socket lock releases it. * * NOTE: Releasing the socket lock while an operation is sleeping overcomes * the problem of a blocked socket operation preventing any other operations * from occurring. However, applications must be careful if they have * multiple threads trying to send (or receive) on the same socket, as these * operations might interfere with each other. For example, doing a connect * and a receive at the same time might allow the receive to consume the * ACK message meant for the connect. While additional work could be done * to try and overcome this, it doesn't seem to be worthwhile at the present. * * NOTE: Releasing the socket lock while an operation is sleeping also ensures * that another operation that must be performed in a non-blocking manner is * not delayed for very long because the lock has already been taken. * * NOTE: This code assumes that certain fields of a port/socket pair are * constant over its lifetime; such fields can be examined without taking * the socket lock and/or port lock, and do not need to be re-read even * after resuming processing after waiting. These fields include: * - socket type * - pointer to socket sk structure (aka tipc_sock structure) * - pointer to port structure * - port reference */ #include "socket.h" /** * advance_rx_queue - discard first buffer in socket receive queue * * Caller must hold socket lock */ static void advance_rx_queue(struct sock *sk) { kfree_skb(__skb_dequeue(&sk->sk_receive_queue)); } /** * reject_rx_queue - reject all buffers in socket receive queue * * Caller must hold socket lock */ static void reject_rx_queue(struct sock *sk) { struct sk_buff *buf; u32 dnode; while ((buf = __skb_dequeue(&sk->sk_receive_queue))) { if (tipc_msg_reverse(buf, &dnode, TIPC_ERR_NO_PORT)) tipc_link_xmit(buf, dnode, 0); } } /** * 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. * * Returns 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; socket_state state; struct sock *sk; struct tipc_sock *tsk; struct tipc_port *port; u32 ref; /* Validate arguments */ if (unlikely(protocol != 0)) return -EPROTONOSUPPORT; switch (sock->type) { case SOCK_STREAM: ops = &stream_ops; state = SS_UNCONNECTED; break; case SOCK_SEQPACKET: ops = &packet_ops; state = SS_UNCONNECTED; break; case SOCK_DGRAM: case SOCK_RDM: ops = &msg_ops; state = SS_READY; break; default: return -EPROTOTYPE; } /* Allocate socket's protocol area */ if (!kern) sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto); else sk = sk_alloc(net, AF_TIPC, GFP_KERNEL, &tipc_proto_kern); if (sk == NULL) return -ENOMEM; tsk = tipc_sk(sk); port = &tsk->port; ref = tipc_port_init(port, TIPC_LOW_IMPORTANCE); if (!ref) { pr_warn("Socket registration failed, ref. table exhausted\n"); sk_free(sk); return -ENOMEM; } /* Finish initializing socket data structures */ sock->ops = ops; sock->state = state; sock_init_data(sock, sk); sk->sk_backlog_rcv = tipc_backlog_rcv; sk->sk_rcvbuf = sysctl_tipc_rmem[1]; sk->sk_data_ready = tipc_data_ready; sk->sk_write_space = tipc_write_space; tsk->conn_timeout = CONN_TIMEOUT_DEFAULT; tsk->sent_unacked = 0; atomic_set(&tsk->dupl_rcvcnt, 0); tipc_port_unlock(port); if (sock->state == SS_READY) { tipc_port_set_unreturnable(port, true); if (sock->type == SOCK_DGRAM) tipc_port_set_unreliable(port, true); } return 0; } /** * tipc_sock_create_local - create TIPC socket from inside TIPC module * @type: socket type - SOCK_RDM or SOCK_SEQPACKET * * We cannot use sock_creat_kern here because it bumps module user count. * Since socket owner and creator is the same module we must make sure * that module count remains zero for module local sockets, otherwise * we cannot do rmmod. * * Returns 0 on success, errno otherwise */ int tipc_sock_create_local(int type, struct socket **res) { int rc; rc = sock_create_lite(AF_TIPC, type, 0, res); if (rc < 0) { pr_err("Failed to create kernel socket\n"); return rc; } tipc_sk_create(&init_net, *res, 0, 1); return 0; } /** * tipc_sock_release_local - release socket created by tipc_sock_create_local * @sock: the socket to be released. * * Module reference count is not incremented when such sockets are created, * so we must keep it from being decremented when they are released. */ void tipc_sock_release_local(struct socket *sock) { tipc_release(sock); sock->ops = NULL; sock_release(sock); } /** * tipc_sock_accept_local - accept a connection on a socket created * with tipc_sock_create_local. Use this function to avoid that * module reference count is inadvertently incremented. * * @sock: the accepting socket * @newsock: reference to the new socket to be created * @flags: socket flags */ int tipc_sock_accept_local(struct socket *sock, struct socket **newsock, int flags) { struct sock *sk = sock->sk; int ret; ret = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol, newsock); if (ret < 0) return ret; ret = tipc_accept(sock, *newsock, flags); if (ret < 0) { sock_release(*newsock); return ret; } (*newsock)->ops = sock->ops; return ret; } /** * 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. * * Returns 0 on success, errno otherwise */ static int tipc_release(struct socket *sock) { struct sock *sk = sock->sk; struct tipc_sock *tsk; struct tipc_port *port; struct sk_buff *buf; u32 dnode; /* * 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); port = &tsk->port; lock_sock(sk); /* * Reject all unreceived messages, except on an active connection * (which disconnects locally & sends a 'FIN+' to peer) */ while (sock->state != SS_DISCONNECTING) { buf = __skb_dequeue(&sk->sk_receive_queue); if (buf == NULL) break; if (TIPC_SKB_CB(buf)->handle != NULL) kfree_skb(buf); else { if ((sock->state == SS_CONNECTING) || (sock->state == SS_CONNECTED)) { sock->state = SS_DISCONNECTING; tipc_port_disconnect(port->ref); } if (tipc_msg_reverse(buf, &dnode, TIPC_ERR_NO_PORT)) tipc_link_xmit(buf, dnode, 0); } } /* Destroy TIPC port; also disconnects an active connection and * sends a 'FIN-' to peer. */ tipc_port_destroy(port); /* Discard any remaining (connection-based) messages in receive queue */ __skb_queue_purge(&sk->sk_receive_queue); /* Reject any messages that accumulated in backlog queue */ sock->state = SS_DISCONNECTING; release_sock(sk); sock_put(sk); sock->sk = NULL; return 0; } /** * tipc_bind - associate or disassocate TIPC name(s) with a socket * @sock: socket structure * @uaddr: socket address describing name(s) and desired operation * @uaddr_len: 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. * * Returns 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 *uaddr, int uaddr_len) { struct sock *sk = sock->sk; struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr; struct tipc_sock *tsk = tipc_sk(sk); int res = -EINVAL; lock_sock(sk); if (unlikely(!uaddr_len)) { res = tipc_withdraw(&tsk->port, 0, NULL); goto exit; } if (uaddr_len < sizeof(struct sockaddr_tipc)) { res = -EINVAL; goto exit; } if (addr->family != AF_TIPC) { res = -EAFNOSUPPORT; goto exit; } if (addr->addrtype == TIPC_ADDR_NAME) addr->addr.nameseq.upper = addr->addr.nameseq.lower; else if (addr->addrtype != TIPC_ADDR_NAMESEQ) { res = -EAFNOSUPPORT; goto exit; } if ((addr->addr.nameseq.type < TIPC_RESERVED_TYPES) && (addr->addr.nameseq.type != TIPC_TOP_SRV) && (addr->addr.nameseq.type != TIPC_CFG_SRV)) { res = -EACCES; goto exit; } res = (addr->scope > 0) ? tipc_publish(&tsk->port, addr->scope, &addr->addr.nameseq) : tipc_withdraw(&tsk->port, -addr->scope, &addr->addr.nameseq); exit: release_sock(sk); return res; } /** * tipc_getname - get port ID of socket or peer socket * @sock: socket structure * @uaddr: area for returned socket address * @uaddr_len: area for returned length of socket address * @peer: 0 = own ID, 1 = current peer ID, 2 = current/former peer ID * * Returns 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 *uaddr_len, int peer) { struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr; struct tipc_sock *tsk = tipc_sk(sock->sk); memset(addr, 0, sizeof(*addr)); if (peer) { if ((sock->state != SS_CONNECTED) && ((peer != 2) || (sock->state != SS_DISCONNECTING))) return -ENOTCONN; addr->addr.id.ref = tipc_port_peerport(&tsk->port); addr->addr.id.node = tipc_port_peernode(&tsk->port); } else { addr->addr.id.ref = tsk->port.ref; addr->addr.id.node = tipc_own_addr; } *uaddr_len = sizeof(*addr); addr->addrtype = TIPC_ADDR_ID; addr->family = AF_TIPC; addr->scope = 0; addr->addr.name.domain = 0; return 0; } /** * 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: ??? * * Returns 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 ... * * TIPC sets the returned events as follows: * * socket state flags set * ------------ --------- * unconnected no read flags * POLLOUT if port is not congested * * connecting POLLIN/POLLRDNORM if ACK/NACK in rx queue * no write flags * * connected POLLIN/POLLRDNORM if data in rx queue * POLLOUT if port is not congested * * disconnecting POLLIN/POLLRDNORM/POLLHUP * no write flags * * listening POLLIN if SYN in rx queue * no write flags * * ready POLLIN/POLLRDNORM if data in rx queue * [connectionless] POLLOUT (since port cannot be congested) * * 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 unsigned int tipc_poll(struct file *file, struct socket *sock, poll_table *wait) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); u32 mask = 0; sock_poll_wait(file, sk_sleep(sk), wait); switch ((int)sock->state) { case SS_UNCONNECTED: if (!tsk->link_cong) mask |= POLLOUT; break; case SS_READY: case SS_CONNECTED: if (!tsk->link_cong && !tipc_sk_conn_cong(tsk)) mask |= POLLOUT; /* fall thru' */ case SS_CONNECTING: case SS_LISTENING: if (!skb_queue_empty(&sk->sk_receive_queue)) mask |= (POLLIN | POLLRDNORM); break; case SS_DISCONNECTING: mask = (POLLIN | POLLRDNORM | POLLHUP); break; } return mask; } /** * tipc_sendmcast - send multicast message * @sock: socket structure * @seq: destination address * @iov: message data to send * @dsz: total length of message data * @timeo: timeout to wait for wakeup * * Called from function tipc_sendmsg(), which has done all sanity checks * Returns the number of bytes sent on success, or errno */ static int tipc_sendmcast(struct socket *sock, struct tipc_name_seq *seq, struct iovec *iov, size_t dsz, long timeo) { struct sock *sk = sock->sk; struct tipc_msg *mhdr = &tipc_sk(sk)->port.phdr; struct sk_buff *buf; uint mtu; int rc; msg_set_type(mhdr, TIPC_MCAST_MSG); msg_set_lookup_scope(mhdr, TIPC_CLUSTER_SCOPE); msg_set_destport(mhdr, 0); msg_set_destnode(mhdr, 0); msg_set_nametype(mhdr, seq->type); msg_set_namelower(mhdr, seq->lower); msg_set_nameupper(mhdr, seq->upper); msg_set_hdr_sz(mhdr, MCAST_H_SIZE); new_mtu: mtu = tipc_bclink_get_mtu(); rc = tipc_msg_build(mhdr, iov, 0, dsz, mtu, &buf); if (unlikely(rc < 0)) return rc; do { rc = tipc_bclink_xmit(buf); if (likely(rc >= 0)) { rc = dsz; break; } if (rc == -EMSGSIZE) goto new_mtu; if (rc != -ELINKCONG) break; rc = tipc_wait_for_sndmsg(sock, &timeo); if (rc) kfree_skb_list(buf); } while (!rc); return rc; } /* tipc_sk_mcast_rcv - Deliver multicast message to all destination sockets */ void tipc_sk_mcast_rcv(struct sk_buff *buf) { struct tipc_msg *msg = buf_msg(buf); struct tipc_port_list dports = {0, NULL, }; struct tipc_port_list *item; struct sk_buff *b; uint i, last, dst = 0; u32 scope = TIPC_CLUSTER_SCOPE; if (in_own_node(msg_orignode(msg))) scope = TIPC_NODE_SCOPE; /* Create destination port list: */ tipc_nametbl_mc_translate(msg_nametype(msg), msg_namelower(msg), msg_nameupper(msg), scope, &dports); last = dports.count; if (!last) { kfree_skb(buf); return; } for (item = &dports; item; item = item->next) { for (i = 0; i < PLSIZE && ++dst <= last; i++) { b = (dst != last) ? skb_clone(buf, GFP_ATOMIC) : buf; if (!b) { pr_warn("Failed do clone mcast rcv buffer\n"); continue; } msg_set_destport(msg, item->ports[i]); tipc_sk_rcv(b); } } tipc_port_list_free(&dports); } /** * tipc_sk_proto_rcv - receive a connection mng protocol message * @tsk: receiving socket * @dnode: node to send response message to, if any * @buf: buffer containing protocol message * Returns 0 (TIPC_OK) if message was consumed, 1 (TIPC_FWD_MSG) if * (CONN_PROBE_REPLY) message should be forwarded. */ static int tipc_sk_proto_rcv(struct tipc_sock *tsk, u32 *dnode, struct sk_buff *buf) { struct tipc_msg *msg = buf_msg(buf); struct tipc_port *port = &tsk->port; int conn_cong; /* Ignore if connection cannot be validated: */ if (!port->connected || !tipc_port_peer_msg(port, msg)) goto exit; port->probing_state = TIPC_CONN_OK; if (msg_type(msg) == CONN_ACK) { conn_cong = tipc_sk_conn_cong(tsk); tsk->sent_unacked -= msg_msgcnt(msg); if (conn_cong) tipc_sock_wakeup(tsk); } else if (msg_type(msg) == CONN_PROBE) { if (!tipc_msg_reverse(buf, dnode, TIPC_OK)) return TIPC_OK; msg_set_type(msg, CONN_PROBE_REPLY); return TIPC_FWD_MSG; } /* Do nothing if msg_type() == CONN_PROBE_REPLY */ exit: kfree_skb(buf); return TIPC_OK; } /** * dest_name_check - verify user is permitted to send to specified port name * @dest: destination address * @m: descriptor for message to be sent * * Prevents restricted configuration commands from being issued by * unauthorized users. * * Returns 0 if permission is granted, otherwise errno */ static int dest_name_check(struct sockaddr_tipc *dest, struct msghdr *m) { struct tipc_cfg_msg_hdr hdr; if (unlikely(dest->addrtype == TIPC_ADDR_ID)) return 0; if (likely(dest->addr.name.name.type >= TIPC_RESERVED_TYPES)) return 0; if (likely(dest->addr.name.name.type == TIPC_TOP_SRV)) return 0; if (likely(dest->addr.name.name.type != TIPC_CFG_SRV)) return -EACCES; if (!m->msg_iovlen || (m->msg_iov[0].iov_len < sizeof(hdr))) return -EMSGSIZE; if (copy_from_user(&hdr, m->msg_iov[0].iov_base, sizeof(hdr))) return -EFAULT; if ((ntohs(hdr.tcm_type) & 0xC000) && (!capable(CAP_NET_ADMIN))) return -EACCES; return 0; } static int tipc_wait_for_sndmsg(struct socket *sock, long *timeo_p) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); DEFINE_WAIT(wait); int done; do { int err = sock_error(sk); if (err) return err; if (sock->state == SS_DISCONNECTING) return -EPIPE; if (!*timeo_p) return -EAGAIN; if (signal_pending(current)) return sock_intr_errno(*timeo_p); prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); done = sk_wait_event(sk, timeo_p, !tsk->link_cong); finish_wait(sk_sleep(sk), &wait); } while (!done); return 0; } /** * tipc_sendmsg - send message in connectionless manner * @iocb: if NULL, indicates that socket lock is already held * @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.) * * Returns the number of bytes sent on success, or errno otherwise */ static int tipc_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t dsz) { DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name); struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_port *port = &tsk->port; struct tipc_msg *mhdr = &port->phdr; struct iovec *iov = m->msg_iov; u32 dnode, dport; struct sk_buff *buf; struct tipc_name_seq *seq = &dest->addr.nameseq; u32 mtu; long timeo; int rc = -EINVAL; if (unlikely(!dest)) return -EDESTADDRREQ; if (unlikely((m->msg_namelen < sizeof(*dest)) || (dest->family != AF_TIPC))) return -EINVAL; if (dsz > TIPC_MAX_USER_MSG_SIZE) return -EMSGSIZE; if (iocb) lock_sock(sk); if (unlikely(sock->state != SS_READY)) { if (sock->state == SS_LISTENING) { rc = -EPIPE; goto exit; } if (sock->state != SS_UNCONNECTED) { rc = -EISCONN; goto exit; } if (tsk->port.published) { rc = -EOPNOTSUPP; goto exit; } if (dest->addrtype == TIPC_ADDR_NAME) { tsk->port.conn_type = dest->addr.name.name.type; tsk->port.conn_instance = dest->addr.name.name.instance; } } rc = dest_name_check(dest, m); if (rc) goto exit; timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT); if (dest->addrtype == TIPC_ADDR_MCAST) { rc = tipc_sendmcast(sock, seq, iov, dsz, timeo); goto exit; } else if (dest->addrtype == TIPC_ADDR_NAME) { u32 type = dest->addr.name.name.type; u32 inst = dest->addr.name.name.instance; u32 domain = dest->addr.name.domain; dnode = domain; msg_set_type(mhdr, TIPC_NAMED_MSG); msg_set_hdr_sz(mhdr, NAMED_H_SIZE); msg_set_nametype(mhdr, type); msg_set_nameinst(mhdr, inst); msg_set_lookup_scope(mhdr, tipc_addr_scope(domain)); dport = tipc_nametbl_translate(type, inst, &dnode); msg_set_destnode(mhdr, dnode); msg_set_destport(mhdr, dport); if (unlikely(!dport && !dnode)) { rc = -EHOSTUNREACH; goto exit; } } else if (dest->addrtype == TIPC_ADDR_ID) { dnode = dest->addr.id.node; msg_set_type(mhdr, TIPC_DIRECT_MSG); msg_set_lookup_scope(mhdr, 0); msg_set_destnode(mhdr, dnode); msg_set_destport(mhdr, dest->addr.id.ref); msg_set_hdr_sz(mhdr, BASIC_H_SIZE); } new_mtu: mtu = tipc_node_get_mtu(dnode, tsk->port.ref); rc = tipc_msg_build(mhdr, iov, 0, dsz, mtu, &buf); if (rc < 0) goto exit; do { rc = tipc_link_xmit(buf, dnode, tsk->port.ref); if (likely(rc >= 0)) { if (sock->state != SS_READY) sock->state = SS_CONNECTING; rc = dsz; break; } if (rc == -EMSGSIZE) goto new_mtu; if (rc != -ELINKCONG) break; rc = tipc_wait_for_sndmsg(sock, &timeo); if (rc) kfree_skb_list(buf); } while (!rc); exit: if (iocb) release_sock(sk); return rc; } static int tipc_wait_for_sndpkt(struct socket *sock, long *timeo_p) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); DEFINE_WAIT(wait); int done; do { int err = sock_error(sk); if (err) return err; if (sock->state == SS_DISCONNECTING) return -EPIPE; else if (sock->state != SS_CONNECTED) return -ENOTCONN; if (!*timeo_p) return -EAGAIN; if (signal_pending(current)) return sock_intr_errno(*timeo_p); prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); done = sk_wait_event(sk, timeo_p, (!tsk->link_cong && !tipc_sk_conn_cong(tsk)) || !tsk->port.connected); finish_wait(sk_sleep(sk), &wait); } while (!done); return 0; } /** * tipc_send_stream - send stream-oriented data * @iocb: (unused) * @sock: socket structure * @m: data to send * @dsz: total length of data to be transmitted * * Used for SOCK_STREAM data. * * Returns the number of bytes sent on success (or partial success), * or errno if no data sent */ static int tipc_send_stream(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t dsz) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_port *port = &tsk->port; struct tipc_msg *mhdr = &port->phdr; struct sk_buff *buf; DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name); u32 ref = port->ref; int rc = -EINVAL; long timeo; u32 dnode; uint mtu, send, sent = 0; /* Handle implied connection establishment */ if (unlikely(dest)) { rc = tipc_sendmsg(iocb, sock, m, dsz); if (dsz && (dsz == rc)) tsk->sent_unacked = 1; return rc; } if (dsz > (uint)INT_MAX) return -EMSGSIZE; if (iocb) lock_sock(sk); if (unlikely(sock->state != SS_CONNECTED)) { if (sock->state == SS_DISCONNECTING) rc = -EPIPE; else rc = -ENOTCONN; goto exit; } timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT); dnode = tipc_port_peernode(port); next: mtu = port->max_pkt; send = min_t(uint, dsz - sent, TIPC_MAX_USER_MSG_SIZE); rc = tipc_msg_build(mhdr, m->msg_iov, sent, send, mtu, &buf); if (unlikely(rc < 0)) goto exit; do { if (likely(!tipc_sk_conn_cong(tsk))) { rc = tipc_link_xmit(buf, dnode, ref); if (likely(!rc)) { tsk->sent_unacked++; sent += send; if (sent == dsz) break; goto next; } if (rc == -EMSGSIZE) { port->max_pkt = tipc_node_get_mtu(dnode, ref); goto next; } if (rc != -ELINKCONG) break; } rc = tipc_wait_for_sndpkt(sock, &timeo); if (rc) kfree_skb_list(buf); } while (!rc); exit: if (iocb) release_sock(sk); return sent ? sent : rc; } /** * tipc_send_packet - send a connection-oriented message * @iocb: if NULL, indicates that socket lock is already held * @sock: socket structure * @m: message to send * @dsz: length of data to be transmitted * * Used for SOCK_SEQPACKET messages. * * Returns the number of bytes sent on success, or errno otherwise */ static int tipc_send_packet(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t dsz) { if (dsz > TIPC_MAX_USER_MSG_SIZE) return -EMSGSIZE; return tipc_send_stream(iocb, sock, m, dsz); } /** * auto_connect - complete connection setup to a remote port * @tsk: tipc socket structure * @msg: peer's response message * * Returns 0 on success, errno otherwise */ static int auto_connect(struct tipc_sock *tsk, struct tipc_msg *msg) { struct tipc_port *port = &tsk->port; struct socket *sock = tsk->sk.sk_socket; struct tipc_portid peer; peer.ref = msg_origport(msg); peer.node = msg_orignode(msg); __tipc_port_connect(port->ref, port, &peer); if (msg_importance(msg) > TIPC_CRITICAL_IMPORTANCE) return -EINVAL; msg_set_importance(&port->phdr, (u32)msg_importance(msg)); sock->state = SS_CONNECTED; return 0; } /** * set_orig_addr - capture sender's address for received message * @m: descriptor for message info * @msg: received message header * * Note: Address is not captured if not requested by receiver. */ static void set_orig_addr(struct msghdr *m, struct tipc_msg *msg) { DECLARE_SOCKADDR(struct sockaddr_tipc *, addr, m->msg_name); if (addr) { addr->family = AF_TIPC; addr->addrtype = TIPC_ADDR_ID; memset(&addr->addr, 0, sizeof(addr->addr)); addr->addr.id.ref = msg_origport(msg); addr->addr.id.node = msg_orignode(msg); addr->addr.name.domain = 0; /* could leave uninitialized */ addr->scope = 0; /* could leave uninitialized */ m->msg_namelen = sizeof(struct sockaddr_tipc); } } /** * anc_data_recv - optionally capture ancillary data for received message * @m: descriptor for message info * @msg: received message header * @tport: TIPC port associated with message * * Note: Ancillary data is not captured if not requested by receiver. * * Returns 0 if successful, otherwise errno */ static int anc_data_recv(struct msghdr *m, struct tipc_msg *msg, struct tipc_port *tport) { u32 anc_data[3]; u32 err; u32 dest_type; int has_name; int res; if (likely(m->msg_controllen == 0)) return 0; /* 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]) { 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 = (tport->conn_type != 0); anc_data[0] = tport->conn_type; anc_data[1] = tport->conn_instance; anc_data[2] = tport->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 int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop) { struct sock *sk = sock->sk; DEFINE_WAIT(wait); long timeo = *timeop; int err; for (;;) { prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); if (timeo && skb_queue_empty(&sk->sk_receive_queue)) { if (sock->state == SS_DISCONNECTING) { err = -ENOTCONN; break; } release_sock(sk); timeo = schedule_timeout(timeo); lock_sock(sk); } err = 0; if (!skb_queue_empty(&sk->sk_receive_queue)) break; err = sock_intr_errno(timeo); if (signal_pending(current)) break; err = -EAGAIN; if (!timeo) break; } finish_wait(sk_sleep(sk), &wait); *timeop = timeo; return err; } /** * tipc_recvmsg - receive packet-oriented message * @iocb: (unused) * @m: descriptor for message info * @buf_len: total size 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. * * Returns size of returned message data, errno otherwise */ static int tipc_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t buf_len, int flags) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_port *port = &tsk->port; struct sk_buff *buf; struct tipc_msg *msg; long timeo; unsigned int sz; u32 err; int res; /* Catch invalid receive requests */ if (unlikely(!buf_len)) return -EINVAL; lock_sock(sk); if (unlikely(sock->state == SS_UNCONNECTED)) { res = -ENOTCONN; goto exit; } timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); restart: /* Look for a message in receive queue; wait if necessary */ res = tipc_wait_for_rcvmsg(sock, &timeo); if (res) goto exit; /* Look at first message in receive queue */ buf = skb_peek(&sk->sk_receive_queue); msg = buf_msg(buf); sz = msg_data_sz(msg); err = msg_errcode(msg); /* Discard an empty non-errored message & try again */ if ((!sz) && (!err)) { advance_rx_queue(sk); goto restart; } /* Capture sender's address (optional) */ set_orig_addr(m, msg); /* Capture ancillary data (optional) */ res = anc_data_recv(m, msg, port); if (res) goto exit; /* Capture message data (if valid) & compute return value (always) */ if (!err) { if (unlikely(buf_len < sz)) { sz = buf_len; m->msg_flags |= MSG_TRUNC; } res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg), m->msg_iov, sz); if (res) goto exit; res = sz; } else { if ((sock->state == SS_READY) || ((err == TIPC_CONN_SHUTDOWN) || m->msg_control)) res = 0; else res = -ECONNRESET; } /* Consume received message (optional) */ if (likely(!(flags & MSG_PEEK))) { if ((sock->state != SS_READY) && (++tsk->rcv_unacked >= TIPC_CONNACK_INTV)) { tipc_acknowledge(port->ref, tsk->rcv_unacked); tsk->rcv_unacked = 0; } advance_rx_queue(sk); } exit: release_sock(sk); return res; } /** * tipc_recv_stream - receive stream-oriented data * @iocb: (unused) * @m: descriptor for message info * @buf_len: 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. * * Returns size of returned message data, errno otherwise */ static int tipc_recv_stream(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t buf_len, int flags) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_port *port = &tsk->port; struct sk_buff *buf; struct tipc_msg *msg; long timeo; unsigned int sz; int sz_to_copy, target, needed; int sz_copied = 0; u32 err; int res = 0; /* Catch invalid receive attempts */ if (unlikely(!buf_len)) return -EINVAL; lock_sock(sk); if (unlikely(sock->state == SS_UNCONNECTED)) { res = -ENOTCONN; goto exit; } target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len); timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); restart: /* Look for a message in receive queue; wait if necessary */ res = tipc_wait_for_rcvmsg(sock, &timeo); if (res) goto exit; /* Look at first message in receive queue */ buf = skb_peek(&sk->sk_receive_queue); msg = buf_msg(buf); sz = msg_data_sz(msg); err = msg_errcode(msg); /* Discard an empty non-errored message & try again */ if ((!sz) && (!err)) { advance_rx_queue(sk); goto restart; } /* Optionally capture sender's address & ancillary data of first msg */ if (sz_copied == 0) { set_orig_addr(m, msg); res = anc_data_recv(m, msg, port); if (res) goto exit; } /* Capture message data (if valid) & compute return value (always) */ if (!err) { u32 offset = (u32)(unsigned long)(TIPC_SKB_CB(buf)->handle); sz -= offset; needed = (buf_len - sz_copied); sz_to_copy = (sz <= needed) ? sz : needed; res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg) + offset, m->msg_iov, sz_to_copy); if (res) goto exit; sz_copied += sz_to_copy; if (sz_to_copy < sz) { if (!(flags & MSG_PEEK)) TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)(offset + sz_to_copy); goto exit; } } else { if (sz_copied != 0) goto exit; /* can't add error msg to valid data */ if ((err == TIPC_CONN_SHUTDOWN) || m->msg_control) res = 0; else res = -ECONNRESET; } /* Consume received message (optional) */ if (likely(!(flags & MSG_PEEK))) { if (unlikely(++tsk->rcv_unacked >= TIPC_CONNACK_INTV)) { tipc_acknowledge(port->ref, tsk->rcv_unacked); tsk->rcv_unacked = 0; } advance_rx_queue(sk); } /* Loop around if more data is required */ if ((sz_copied < buf_len) && /* didn't get all requested data */ (!skb_queue_empty(&sk->sk_receive_queue) || (sz_copied < target)) && /* and more is ready or required */ (!(flags & MSG_PEEK)) && /* and aren't just peeking at data */ (!err)) /* and haven't reached a FIN */ goto restart; exit: release_sock(sk); return sz_copied ? sz_copied : res; } /** * 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 (wq_has_sleeper(wq)) wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | POLLWRNORM | POLLWRBAND); rcu_read_unlock(); } /** * tipc_data_ready - wake up threads to indicate messages have been received * @sk: socket * @len: the length of messages */ static void tipc_data_ready(struct sock *sk) { struct socket_wq *wq; rcu_read_lock(); wq = rcu_dereference(sk->sk_wq); if (wq_has_sleeper(wq)) wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLRDNORM | POLLRDBAND); rcu_read_unlock(); } /** * filter_connect - Handle all incoming messages for a connection-based socket * @tsk: TIPC socket * @msg: message * * Returns 0 (TIPC_OK) if everyting ok, -TIPC_ERR_NO_PORT otherwise */ static int filter_connect(struct tipc_sock *tsk, struct sk_buff **buf) { struct sock *sk = &tsk->sk; struct tipc_port *port = &tsk->port; struct socket *sock = sk->sk_socket; struct tipc_msg *msg = buf_msg(*buf); int retval = -TIPC_ERR_NO_PORT; int res; if (msg_mcast(msg)) return retval; switch ((int)sock->state) { case SS_CONNECTED: /* Accept only connection-based messages sent by peer */ if (msg_connected(msg) && tipc_port_peer_msg(port, msg)) { if (unlikely(msg_errcode(msg))) { sock->state = SS_DISCONNECTING; __tipc_port_disconnect(port); } retval = TIPC_OK; } break; case SS_CONNECTING: /* Accept only ACK or NACK message */ if (unlikely(msg_errcode(msg))) { sock->state = SS_DISCONNECTING; sk->sk_err = ECONNREFUSED; retval = TIPC_OK; break; } if (unlikely(!msg_connected(msg))) break; res = auto_connect(tsk, msg); if (res) { sock->state = SS_DISCONNECTING; sk->sk_err = -res; retval = TIPC_OK; break; } /* If an incoming message is an 'ACK-', it should be * discarded here because it doesn't contain useful * data. In addition, we should try to wake up * connect() routine if sleeping. */ if (msg_data_sz(msg) == 0) { kfree_skb(*buf); *buf = NULL; if (waitqueue_active(sk_sleep(sk))) wake_up_interruptible(sk_sleep(sk)); } retval = TIPC_OK; break; case SS_LISTENING: case SS_UNCONNECTED: /* Accept only SYN message */ if (!msg_connected(msg) && !(msg_errcode(msg))) retval = TIPC_OK; break; case SS_DISCONNECTING: break; default: pr_err("Unknown socket state %u\n", sock->state); } return retval; } /** * rcvbuf_limit - get proper overload limit of socket receive queue * @sk: socket * @buf: message * * For all connection oriented messages, irrespective of importance, * the default overload value (i.e. 67MB) is set as limit. * * For all connectionless messages, by default new queue limits are * as belows: * * TIPC_LOW_IMPORTANCE (4 MB) * TIPC_MEDIUM_IMPORTANCE (8 MB) * TIPC_HIGH_IMPORTANCE (16 MB) * TIPC_CRITICAL_IMPORTANCE (32 MB) * * Returns overload limit according to corresponding message importance */ static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *buf) { struct tipc_msg *msg = buf_msg(buf); if (msg_connected(msg)) return sysctl_tipc_rmem[2]; return sk->sk_rcvbuf >> TIPC_CRITICAL_IMPORTANCE << msg_importance(msg); } /** * filter_rcv - validate incoming message * @sk: socket * @buf: message * * Enqueues message on receive queue if acceptable; optionally handles * disconnect indication for a connected socket. * * Called with socket lock already taken; port lock may also be taken. * * Returns 0 (TIPC_OK) if message was consumed, -TIPC error code if message * to be rejected, 1 (TIPC_FWD_MSG) if (CONN_MANAGER) message to be forwarded */ static int filter_rcv(struct sock *sk, struct sk_buff *buf) { struct socket *sock = sk->sk_socket; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_msg *msg = buf_msg(buf); unsigned int limit = rcvbuf_limit(sk, buf); u32 onode; int rc = TIPC_OK; if (unlikely(msg_user(msg) == CONN_MANAGER)) return tipc_sk_proto_rcv(tsk, &onode, buf); /* Reject message if it is wrong sort of message for socket */ if (msg_type(msg) > TIPC_DIRECT_MSG) return -TIPC_ERR_NO_PORT; if (sock->state == SS_READY) { if (msg_connected(msg)) return -TIPC_ERR_NO_PORT; } else { rc = filter_connect(tsk, &buf); if (rc != TIPC_OK || buf == NULL) return rc; } /* Reject message if there isn't room to queue it */ if (sk_rmem_alloc_get(sk) + buf->truesize >= limit) return -TIPC_ERR_OVERLOAD; /* Enqueue message */ TIPC_SKB_CB(buf)->handle = NULL; __skb_queue_tail(&sk->sk_receive_queue, buf); skb_set_owner_r(buf, sk); sk->sk_data_ready(sk); return TIPC_OK; } /** * tipc_backlog_rcv - handle incoming message from backlog queue * @sk: socket * @buf: message * * Caller must hold socket lock, but not port lock. * * Returns 0 */ static int tipc_backlog_rcv(struct sock *sk, struct sk_buff *buf) { int rc; u32 onode; struct tipc_sock *tsk = tipc_sk(sk); uint truesize = buf->truesize; rc = filter_rcv(sk, buf); if (likely(!rc)) { if (atomic_read(&tsk->dupl_rcvcnt) < TIPC_CONN_OVERLOAD_LIMIT) atomic_add(truesize, &tsk->dupl_rcvcnt); return 0; } if ((rc < 0) && !tipc_msg_reverse(buf, &onode, -rc)) return 0; tipc_link_xmit(buf, onode, 0); return 0; } /** * tipc_sk_rcv - handle incoming message * @buf: buffer containing arriving message * Consumes buffer * Returns 0 if success, or errno: -EHOSTUNREACH */ int tipc_sk_rcv(struct sk_buff *buf) { struct tipc_sock *tsk; struct tipc_port *port; struct sock *sk; u32 dport = msg_destport(buf_msg(buf)); int rc = TIPC_OK; uint limit; u32 dnode; /* Validate destination and message */ port = tipc_port_lock(dport); if (unlikely(!port)) { rc = tipc_msg_eval(buf, &dnode); goto exit; } tsk = tipc_port_to_sock(port); sk = &tsk->sk; /* Queue message */ bh_lock_sock(sk); if (!sock_owned_by_user(sk)) { rc = filter_rcv(sk, buf); } else { if (sk->sk_backlog.len == 0) atomic_set(&tsk->dupl_rcvcnt, 0); limit = rcvbuf_limit(sk, buf) + atomic_read(&tsk->dupl_rcvcnt); if (sk_add_backlog(sk, buf, limit)) rc = -TIPC_ERR_OVERLOAD; } bh_unlock_sock(sk); tipc_port_unlock(port); if (likely(!rc)) return 0; exit: if ((rc < 0) && !tipc_msg_reverse(buf, &dnode, -rc)) return -EHOSTUNREACH; tipc_link_xmit(buf, dnode, 0); return (rc < 0) ? -EHOSTUNREACH : 0; } static int tipc_wait_for_connect(struct socket *sock, long *timeo_p) { struct sock *sk = sock->sk; DEFINE_WAIT(wait); 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); prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); done = sk_wait_event(sk, timeo_p, sock->state != SS_CONNECTING); finish_wait(sk_sleep(sk), &wait); } while (!done); return 0; } /** * 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 * * Returns 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 sockaddr_tipc *dst = (struct sockaddr_tipc *)dest; struct msghdr m = {NULL,}; long timeout = (flags & O_NONBLOCK) ? 0 : tipc_sk(sk)->conn_timeout; socket_state previous; int res; lock_sock(sk); /* For now, TIPC does not allow use of connect() with DGRAM/RDM types */ if (sock->state == SS_READY) { res = -EOPNOTSUPP; goto exit; } /* * Reject connection attempt using multicast address * * Note: send_msg() validates the rest of the address fields, * so there's no need to do it here */ if (dst->addrtype == TIPC_ADDR_MCAST) { res = -EINVAL; goto exit; } previous = sock->state; switch (sock->state) { case SS_UNCONNECTED: /* 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(NULL, sock, &m, 0); if ((res < 0) && (res != -EWOULDBLOCK)) goto exit; /* Just entered SS_CONNECTING state; the only * difference is that return value in non-blocking * case is EINPROGRESS, rather than EALREADY. */ res = -EINPROGRESS; case SS_CONNECTING: if (previous == SS_CONNECTING) res = -EALREADY; if (!timeout) 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 SS_CONNECTED: res = -EISCONN; break; default: res = -EINVAL; break; } exit: release_sock(sk); return res; } /** * tipc_listen - allow socket to listen for incoming connections * @sock: socket structure * @len: (unused) * * Returns 0 on success, errno otherwise */ static int tipc_listen(struct socket *sock, int len) { struct sock *sk = sock->sk; int res; lock_sock(sk); if (sock->state != SS_UNCONNECTED) res = -EINVAL; else { sock->state = SS_LISTENING; res = 0; } 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 = -EINVAL; if (sock->state != SS_LISTENING) break; err = sock_intr_errno(timeo); if (signal_pending(current)) break; err = -EAGAIN; if (!timeo) break; } finish_wait(sk_sleep(sk), &wait); return err; } /** * tipc_accept - wait for connection request * @sock: listening socket * @newsock: new socket that is to be connected * @flags: file-related flags associated with socket * * Returns 0 on success, errno otherwise */ static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags) { struct sock *new_sk, *sk = sock->sk; struct sk_buff *buf; struct tipc_port *new_port; struct tipc_msg *msg; struct tipc_portid peer; u32 new_ref; long timeo; int res; lock_sock(sk); if (sock->state != SS_LISTENING) { 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, 1); if (res) goto exit; new_sk = new_sock->sk; new_port = &tipc_sk(new_sk)->port; new_ref = new_port->ref; 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) */ reject_rx_queue(new_sk); /* Connect new socket to it's peer */ peer.ref = msg_origport(msg); peer.node = msg_orignode(msg); tipc_port_connect(new_ref, &peer); new_sock->state = SS_CONNECTED; tipc_port_set_importance(new_port, msg_importance(msg)); if (msg_named(msg)) { new_port->conn_type = msg_nametype(msg); new_port->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,}; advance_rx_queue(sk); tipc_send_packet(NULL, 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. * * Returns 0 on success, errno otherwise */ static int tipc_shutdown(struct socket *sock, int how) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_port *port = &tsk->port; struct sk_buff *buf; u32 peer; int res; if (how != SHUT_RDWR) return -EINVAL; lock_sock(sk); switch (sock->state) { case SS_CONNECTING: case SS_CONNECTED: restart: /* Disconnect and send a 'FIN+' or 'FIN-' message to peer */ buf = __skb_dequeue(&sk->sk_receive_queue); if (buf) { if (TIPC_SKB_CB(buf)->handle != NULL) { kfree_skb(buf); goto restart; } tipc_port_disconnect(port->ref); if (tipc_msg_reverse(buf, &peer, TIPC_CONN_SHUTDOWN)) tipc_link_xmit(buf, peer, 0); } else { tipc_port_shutdown(port->ref); } sock->state = SS_DISCONNECTING; /* fall through */ case SS_DISCONNECTING: /* Discard any unreceived messages */ __skb_queue_purge(&sk->sk_receive_queue); /* Wake up anyone sleeping in poll */ sk->sk_state_change(sk); res = 0; break; default: res = -ENOTCONN; } release_sock(sk); return res; } /** * 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). * * Returns 0 on success, errno otherwise */ static int tipc_setsockopt(struct socket *sock, int lvl, int opt, char __user *ov, unsigned int ol) { struct sock *sk = sock->sk; struct tipc_sock *tsk = tipc_sk(sk); struct tipc_port *port = &tsk->port; u32 value; int res; if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM)) return 0; if (lvl != SOL_TIPC) return -ENOPROTOOPT; if (ol < sizeof(value)) return -EINVAL; res = get_user(value, (u32 __user *)ov); if (res) return res; lock_sock(sk); switch (opt) { case TIPC_IMPORTANCE: tipc_port_set_importance(port, value); break; case TIPC_SRC_DROPPABLE: if (sock->type != SOCK_STREAM) tipc_port_set_unreliable(port, value); else res = -ENOPROTOOPT; break; case TIPC_DEST_DROPPABLE: tipc_port_set_unreturnable(port, value); break; case TIPC_CONN_TIMEOUT: tipc_sk(sk)->conn_timeout = value; /* no need to set "res", since already 0 at this point */ 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). * * Returns 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_port *port = &tsk->port; int len; 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 = tipc_port_importance(port); break; case TIPC_SRC_DROPPABLE: value = tipc_port_unreliable(port); break; case TIPC_DEST_DROPPABLE: value = tipc_port_unreturnable(port); break; case TIPC_CONN_TIMEOUT: value = tipc_sk(sk)->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; 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 *sk, unsigned int cmd, unsigned long arg) { 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(lnr.bearer_id, lnr.peer, lnr.linkname, TIPC_MAX_LINK_NAME)) { if (copy_to_user(argp, &lnr, sizeof(lnr))) return -EFAULT; return 0; } return -EADDRNOTAVAIL; default: return -ENOIOCTLCMD; } } /* 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 = sock_no_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 = sock_no_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 = sock_no_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_stream, .recvmsg = tipc_recv_stream, .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 }; static struct proto tipc_proto_kern = { .name = "TIPC", .obj_size = sizeof(struct tipc_sock), .sysctl_rmem = sysctl_tipc_rmem }; /** * tipc_socket_init - initialize TIPC socket interface * * Returns 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); }