microsoft
/
WSL2-Linux-Kernel
зеркало из https://github.com/microsoft/WSL2-Linux-Kernel.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность
WSL2-Linux-Kernel/net/tipc/socket.c

2025 строки
50 KiB
C
Исходник Ответственный История

/*
* 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 <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 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 = backlog_rcv;
sk->sk_rcvbuf = sysctl_tipc_rmem[1];
sk->sk_data_ready = tipc_data_ready;
sk->sk_write_space = tipc_write_space;
tipc_sk(sk)->conn_timeout = CONN_TIMEOUT_DEFAULT;
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 timeo)
{
struct sock *sk = sock->sk;
DEFINE_WAIT(wait);
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);
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_FLOW_CONTROL_WIN))
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_FLOW_CONTROL_WIN))
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;
}
/**
* 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 backlog_rcv(struct sock *sk, struct sk_buff *buf)
{
u32 res;
res = filter_rcv(sk, buf);
if (res)
tipc_reject_msg(buf, res);
return 0;
}
/**
* tipc_sk_rcv - handle incoming message
* @sk: socket receiving message
* @buf: message
*
* Called with port lock already taken.
*
* Returns TIPC error status code (TIPC_OK if message is not to be rejected)
*/
u32 tipc_sk_rcv(struct sock *sk, struct sk_buff *buf)
{
u32 res;
/*
* Process message if socket is unlocked; otherwise add to backlog queue
*
* This code is based on sk_receive_skb(), but must be distinct from it
* since a TIPC-specific filter/reject mechanism is utilized
*/
bh_lock_sock(sk);
if (!sock_owned_by_user(sk)) {
res = filter_rcv(sk, buf);
} else {
if (sk_add_backlog(sk, buf, rcvbuf_limit(sk, buf)))
res = TIPC_ERR_OVERLOAD;
else
res = TIPC_OK;
}
bh_unlock_sock(sk);
return res;
}
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);
}
/* 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 = sock_no_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 = sock_no_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 = sock_no_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);
}
Ссылка в новой задаче Показать git blame Копировать постоянную ссылку