diff options
Diffstat (limited to 'net/tipc/socket.c')
| -rw-r--r-- | net/tipc/socket.c | 2077 |
1 files changed, 2077 insertions, 0 deletions
diff --git a/net/tipc/socket.c b/net/tipc/socket.c new file mode 100644 index 00000000000..ef0475568f9 --- /dev/null +++ b/net/tipc/socket.c @@ -0,0 +1,2077 @@ +/* + * 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 "node.h" + +#include <linux/export.h> + +#define SS_LISTENING -1 /* socket is listening */ +#define SS_READY -2 /* socket is connectionless */ + +#define CONN_TIMEOUT_DEFAULT 8000 /* default connect timeout = 8s */ + +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 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; + + while ((buf = __skb_dequeue(&sk->sk_receive_queue))) + tipc_reject_msg(buf, TIPC_ERR_NO_PORT); +} + +/** + * 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; + 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; + + /* + * 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); + } + tipc_reject_msg(buf, TIPC_ERR_NO_PORT); + } + } + + /* 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->port.congested) + mask |= POLLOUT; + break; + case SS_READY: + case SS_CONNECTED: + if (!tsk->port.congested) + 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; +} + +/** + * 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 (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->port.congested); + 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 + * @total_len: length of message + * + * 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 total_len) +{ + struct sock *sk = sock->sk; + struct tipc_sock *tsk = tipc_sk(sk); + struct tipc_port *port = &tsk->port; + DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name); + int needs_conn; + long timeo; + int res = -EINVAL; + + if (unlikely(!dest)) + return -EDESTADDRREQ; + if (unlikely((m->msg_namelen < sizeof(*dest)) || + (dest->family != AF_TIPC))) + return -EINVAL; + if (total_len > TIPC_MAX_USER_MSG_SIZE) + return -EMSGSIZE; + + if (iocb) + lock_sock(sk); + + needs_conn = (sock->state != SS_READY); + if (unlikely(needs_conn)) { + if (sock->state == SS_LISTENING) { + res = -EPIPE; + goto exit; + } + if (sock->state != SS_UNCONNECTED) { + res = -EISCONN; + goto exit; + } + if (tsk->port.published) { + res = -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; + } + + /* Abort any pending connection attempts (very unlikely) */ + reject_rx_queue(sk); + } + + timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT); + do { + if (dest->addrtype == TIPC_ADDR_NAME) { + res = dest_name_check(dest, m); + if (res) + break; + res = tipc_send2name(port, + &dest->addr.name.name, + dest->addr.name.domain, + m->msg_iov, + total_len); + } else if (dest->addrtype == TIPC_ADDR_ID) { + res = tipc_send2port(port, + &dest->addr.id, + m->msg_iov, + total_len); + } else if (dest->addrtype == TIPC_ADDR_MCAST) { + if (needs_conn) { + res = -EOPNOTSUPP; + break; + } + res = dest_name_check(dest, m); + if (res) + break; + res = tipc_port_mcast_xmit(port, + &dest->addr.nameseq, + m->msg_iov, + total_len); + } + if (likely(res != -ELINKCONG)) { + if (needs_conn && (res >= 0)) + sock->state = SS_CONNECTING; + break; + } + res = tipc_wait_for_sndmsg(sock, &timeo); + if (res) + break; + } while (1); + +exit: + if (iocb) + release_sock(sk); + return res; +} + +static int tipc_wait_for_sndpkt(struct socket *sock, long *timeo_p) +{ + struct sock *sk = sock->sk; + struct tipc_sock *tsk = tipc_sk(sk); + struct tipc_port *port = &tsk->port; + 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, + (!port->congested || !port->connected)); + finish_wait(sk_sleep(sk), &wait); + } while (!done); + return 0; +} + +/** + * 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 + * @total_len: length of message + * + * Used for SOCK_SEQPACKET messages and SOCK_STREAM data. + * + * 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 total_len) +{ + struct sock *sk = sock->sk; + struct tipc_sock *tsk = tipc_sk(sk); + DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name); + int res = -EINVAL; + long timeo; + + /* Handle implied connection establishment */ + if (unlikely(dest)) + return tipc_sendmsg(iocb, sock, m, total_len); + + if (total_len > TIPC_MAX_USER_MSG_SIZE) + return -EMSGSIZE; + + if (iocb) + lock_sock(sk); + + if (unlikely(sock->state != SS_CONNECTED)) { + if (sock->state == SS_DISCONNECTING) + res = -EPIPE; + else + res = -ENOTCONN; + goto exit; + } + + timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT); + do { + res = tipc_send(&tsk->port, m->msg_iov, total_len); + if (likely(res != -ELINKCONG)) + break; + res = tipc_wait_for_sndpkt(sock, &timeo); + if (res) + break; + } while (1); +exit: + if (iocb) + release_sock(sk); + return res; +} + +/** + * tipc_send_stream - send stream-oriented data + * @iocb: (unused) + * @sock: socket structure + * @m: data to send + * @total_len: total length of data to be sent + * + * 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 total_len) +{ + struct sock *sk = sock->sk; + struct tipc_sock *tsk = tipc_sk(sk); + struct msghdr my_msg; + struct iovec my_iov; + struct iovec *curr_iov; + int curr_iovlen; + char __user *curr_start; + u32 hdr_size; + int curr_left; + int bytes_to_send; + int bytes_sent; + int res; + + lock_sock(sk); + + /* Handle special cases where there is no connection */ + if (unlikely(sock->state != SS_CONNECTED)) { + if (sock->state == SS_UNCONNECTED) + res = tipc_send_packet(NULL, sock, m, total_len); + else + res = sock->state == SS_DISCONNECTING ? -EPIPE : -ENOTCONN; + goto exit; + } + + if (unlikely(m->msg_name)) { + res = -EISCONN; + goto exit; + } + + if (total_len > (unsigned int)INT_MAX) { + res = -EMSGSIZE; + goto exit; + } + + /* + * Send each iovec entry using one or more messages + * + * Note: This algorithm is good for the most likely case + * (i.e. one large iovec entry), but could be improved to pass sets + * of small iovec entries into send_packet(). + */ + curr_iov = m->msg_iov; + curr_iovlen = m->msg_iovlen; + my_msg.msg_iov = &my_iov; + my_msg.msg_iovlen = 1; + my_msg.msg_flags = m->msg_flags; + my_msg.msg_name = NULL; + bytes_sent = 0; + + hdr_size = msg_hdr_sz(&tsk->port.phdr); + + while (curr_iovlen--) { + curr_start = curr_iov->iov_base; + curr_left = curr_iov->iov_len; + + while (curr_left) { + bytes_to_send = tsk->port.max_pkt - hdr_size; + if (bytes_to_send > TIPC_MAX_USER_MSG_SIZE) + bytes_to_send = TIPC_MAX_USER_MSG_SIZE; + if (curr_left < bytes_to_send) + bytes_to_send = curr_left; + my_iov.iov_base = curr_start; + my_iov.iov_len = bytes_to_send; + res = tipc_send_packet(NULL, sock, &my_msg, + bytes_to_send); + if (res < 0) { + if (bytes_sent) + res = bytes_sent; + goto exit; + } + curr_left -= bytes_to_send; + curr_start += bytes_to_send; + bytes_sent += bytes_to_send; + } + + curr_iov++; + } + res = bytes_sent; +exit: + release_sock(sk); + return res; +} + +/** + * 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) && + (++port->conn_unacked >= TIPC_CONNACK_INTV)) + tipc_acknowledge(port->ref, port->conn_unacked); + 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(++port->conn_unacked >= TIPC_CONNACK_INTV)) + tipc_acknowledge(port->ref, port->conn_unacked); + 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 TIPC error status code and socket error status code + * once it encounters some errors + */ +static u32 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); + + u32 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 TIPC error status code (TIPC_OK if message is not to be rejected) + */ +static u32 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 res = TIPC_OK; + + /* 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 { + res = filter_connect(tsk, &buf); + if (res != TIPC_OK || buf == NULL) + return res; + } + + /* 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) +{ + u32 res; + struct tipc_sock *tsk = tipc_sk(sk); + uint truesize = buf->truesize; + + res = filter_rcv(sk, buf); + if (unlikely(res)) + tipc_reject_msg(buf, res); + + if (atomic_read(&tsk->dupl_rcvcnt) < TIPC_CONN_OVERLOAD_LIMIT) + atomic_add(truesize, &tsk->dupl_rcvcnt); + + 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 err = TIPC_OK; + uint limit; + + /* Forward unresolved named message */ + if (unlikely(!dport)) { + tipc_net_route_msg(buf); + return 0; + } + + /* Validate destination */ + port = tipc_port_lock(dport); + if (unlikely(!port)) { + err = TIPC_ERR_NO_PORT; + goto exit; + } + + tsk = tipc_port_to_sock(port); + sk = &tsk->sk; + + /* Queue message */ + bh_lock_sock(sk); + + if (!sock_owned_by_user(sk)) { + err = 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)) + err = TIPC_ERR_OVERLOAD; + } + + bh_unlock_sock(sk); + tipc_port_unlock(port); + + if (likely(!err)) + return 0; +exit: + tipc_reject_msg(buf, err); + return -EHOSTUNREACH; +} + +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; + 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); + tipc_reject_msg(buf, TIPC_CONN_SHUTDOWN); + } 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); +} + +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; + break; + 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); +} |