Exemplo n.º 1
0
static int recv_stream(struct kiocb *iocb, struct socket *sock,
		       struct msghdr *m, size_t buf_len, int flags)
{
	struct tipc_sock *tsock = tipc_sk(sock->sk);
	struct sk_buff *buf;
	struct tipc_msg *msg;
	unsigned int q_len;
	unsigned int sz;
	int sz_to_copy;
	int sz_copied = 0;
	int needed;
	char __user *crs = m->msg_iov->iov_base;
	unsigned char *buf_crs;
	u32 err;
	int res;

	/* Currently doesn't support receiving into multiple iovec entries */

	if (m->msg_iovlen != 1)
		return -EOPNOTSUPP;

	/* Catch invalid receive attempts */

	if (unlikely(!buf_len))
		return -EINVAL;

	if (unlikely(sock->state == SS_DISCONNECTING)) {
		if (skb_queue_len(&sock->sk->sk_receive_queue) == 0)
			return -ENOTCONN;
	} else if (unlikely(sock->state != SS_CONNECTED))
		return -ENOTCONN;

	/* Look for a message in receive queue; wait if necessary */

	if (unlikely(down_interruptible(&tsock->sem)))
		return -ERESTARTSYS;

restart:
	if (unlikely((skb_queue_len(&sock->sk->sk_receive_queue) == 0) &&
		     (flags & MSG_DONTWAIT))) {
		res = -EWOULDBLOCK;
		goto exit;
	}

	if ((res = wait_event_interruptible(
		*sock->sk->sk_sleep,
		((q_len = skb_queue_len(&sock->sk->sk_receive_queue)) ||
		 (sock->state == SS_DISCONNECTING))) )) {
		goto exit;
	}

	/* Catch attempt to receive on an already terminated connection */
	/* [THIS CHECK MAY OVERLAP WITH AN EARLIER CHECK] */

	if (!q_len) {
		res = -ENOTCONN;
		goto exit;
	}

	/* Get access to first message in receive queue */

	buf = skb_peek(&sock->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_queue(tsock);
		goto restart;
	}

	/* Optionally capture sender's address & ancillary data of first msg */

	if (sz_copied == 0) {
		set_orig_addr(m, msg);
		if ((res = anc_data_recv(m, msg, tsock->p)))
			goto exit;
	}

	/* Capture message data (if valid) & compute return value (always) */

	if (!err) {
		buf_crs = (unsigned char *)(TIPC_SKB_CB(buf)->handle);
		sz = skb_tail_pointer(buf) - buf_crs;

		needed = (buf_len - sz_copied);
		sz_to_copy = (sz <= needed) ? sz : needed;
		if (unlikely(copy_to_user(crs, buf_crs, sz_to_copy))) {
			res = -EFAULT;
			goto exit;
		}
		sz_copied += sz_to_copy;

		if (sz_to_copy < sz) {
			if (!(flags & MSG_PEEK))
				TIPC_SKB_CB(buf)->handle = buf_crs + sz_to_copy;
			goto exit;
		}

		crs += sz_to_copy;
	} 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(++tsock->p->conn_unacked >= TIPC_FLOW_CONTROL_WIN))
			tipc_acknowledge(tsock->p->ref, tsock->p->conn_unacked);
		advance_queue(tsock);
	}

	/* Loop around if more data is required */

	if ((sz_copied < buf_len)    /* didn't get all requested data */
	    && (flags & MSG_WAITALL) /* ... and need to wait for more */
	    && (!(flags & MSG_PEEK)) /* ... and aren't just peeking at data */
	    && (!err)                /* ... and haven't reached a FIN */
	    )
		goto restart;

exit:
	up(&tsock->sem);
	return sz_copied ? sz_copied : res;
}
Exemplo n.º 2
0
static int recv_msg(struct kiocb *iocb, struct socket *sock,
		    struct msghdr *m, size_t buf_len, int flags)
{
	struct tipc_sock *tsock = tipc_sk(sock->sk);
	struct sk_buff *buf;
	struct tipc_msg *msg;
	unsigned int q_len;
	unsigned int sz;
	u32 err;
	int res;

	/* Currently doesn't support receiving into multiple iovec entries */

	if (m->msg_iovlen != 1)
		return -EOPNOTSUPP;

	/* Catch invalid receive attempts */

	if (unlikely(!buf_len))
		return -EINVAL;

	if (sock->type == SOCK_SEQPACKET) {
		if (unlikely(sock->state == SS_UNCONNECTED))
			return -ENOTCONN;
		if (unlikely((sock->state == SS_DISCONNECTING) &&
			     (skb_queue_len(&sock->sk->sk_receive_queue) == 0)))
			return -ENOTCONN;
	}

	/* Look for a message in receive queue; wait if necessary */

	if (unlikely(down_interruptible(&tsock->sem)))
		return -ERESTARTSYS;

restart:
	if (unlikely((skb_queue_len(&sock->sk->sk_receive_queue) == 0) &&
		     (flags & MSG_DONTWAIT))) {
		res = -EWOULDBLOCK;
		goto exit;
	}

	if ((res = wait_event_interruptible(
		*sock->sk->sk_sleep,
		((q_len = skb_queue_len(&sock->sk->sk_receive_queue)) ||
		 (sock->state == SS_DISCONNECTING))) )) {
		goto exit;
	}

	/* Catch attempt to receive on an already terminated connection */
	/* [THIS CHECK MAY OVERLAP WITH AN EARLIER CHECK] */

	if (!q_len) {
		res = -ENOTCONN;
		goto exit;
	}

	/* Get access to first message in receive queue */

	buf = skb_peek(&sock->sk->sk_receive_queue);
	msg = buf_msg(buf);
	sz = msg_data_sz(msg);
	err = msg_errcode(msg);

	/* Complete connection setup for an implied connect */

	if (unlikely(sock->state == SS_CONNECTING)) {
		if ((res = auto_connect(sock, tsock, msg)))
			goto exit;
	}

	/* Discard an empty non-errored message & try again */

	if ((!sz) && (!err)) {
		advance_queue(tsock);
		goto restart;
	}

	/* Capture sender's address (optional) */

	set_orig_addr(m, msg);

	/* Capture ancillary data (optional) */

	if ((res = anc_data_recv(m, msg, tsock->p)))
		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;
		}
		if (unlikely(copy_to_user(m->msg_iov->iov_base, msg_data(msg),
					  sz))) {
			res = -EFAULT;
			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 (unlikely(++tsock->p->conn_unacked >= TIPC_FLOW_CONTROL_WIN))
			tipc_acknowledge(tsock->p->ref, tsock->p->conn_unacked);
		advance_queue(tsock);
	}
exit:
	up(&tsock->sem);
	return res;
}
Exemplo n.º 3
0
static int connect(struct socket *sock, struct sockaddr *dest, int destlen,
		   int flags)
{
   struct tipc_sock *tsock = tipc_sk(sock->sk);
   struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
   struct msghdr m = {NULL,};
   struct sk_buff *buf;
   struct tipc_msg *msg;
   int res;

   /* For now, TIPC does not allow use of connect() with DGRAM or RDM types */

   if (sock->state == SS_READY)
	   return -EOPNOTSUPP;

   /* Issue Posix-compliant error code if socket is in the wrong state */

   if (sock->state == SS_LISTENING)
	   return -EOPNOTSUPP;
   if (sock->state == SS_CONNECTING)
	   return -EALREADY;
   if (sock->state != SS_UNCONNECTED)
	   return -EISCONN;

   /*
    * 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)
	   return -EINVAL;

   /* Send a 'SYN-' to destination */

   m.msg_name = dest;
   m.msg_namelen = destlen;
   if ((res = send_msg(NULL, sock, &m, 0)) < 0) {
	   sock->state = SS_DISCONNECTING;
	   return res;
   }

   if (down_interruptible(&tsock->sem))
	   return -ERESTARTSYS;

   /* Wait for destination's 'ACK' response */

   res = wait_event_interruptible_timeout(*sock->sk->sk_sleep,
					  skb_queue_len(&sock->sk->sk_receive_queue),
					  sock->sk->sk_rcvtimeo);
   buf = skb_peek(&sock->sk->sk_receive_queue);
   if (res > 0) {
	   msg = buf_msg(buf);
	   res = auto_connect(sock, tsock, msg);
	   if (!res) {
		   if (!msg_data_sz(msg))
			   advance_queue(tsock);
	   }
   } else {
	   if (res == 0) {
		   res = -ETIMEDOUT;
	   } else
		   { /* leave "res" unchanged */ }
	   sock->state = SS_DISCONNECTING;
   }

   up(&tsock->sem);
   return res;
}
Exemplo n.º 4
0
static int accept(struct socket *sock, struct socket *newsock, int flags)
{
	struct tipc_sock *tsock = tipc_sk(sock->sk);
	struct sk_buff *buf;
	int res = -EFAULT;

	if (sock->state == SS_READY)
		return -EOPNOTSUPP;
	if (sock->state != SS_LISTENING)
		return -EINVAL;

	if (unlikely((skb_queue_len(&sock->sk->sk_receive_queue) == 0) &&
		     (flags & O_NONBLOCK)))
		return -EWOULDBLOCK;

	if (down_interruptible(&tsock->sem))
		return -ERESTARTSYS;

	if (wait_event_interruptible(*sock->sk->sk_sleep,
				     skb_queue_len(&sock->sk->sk_receive_queue))) {
		res = -ERESTARTSYS;
		goto exit;
	}
	buf = skb_peek(&sock->sk->sk_receive_queue);

	res = tipc_create(newsock, 0);
	if (!res) {
		struct tipc_sock *new_tsock = tipc_sk(newsock->sk);
		struct tipc_portid id;
		struct tipc_msg *msg = buf_msg(buf);
		u32 new_ref = new_tsock->p->ref;

		id.ref = msg_origport(msg);
		id.node = msg_orignode(msg);
		tipc_connect2port(new_ref, &id);
		newsock->state = SS_CONNECTED;

		tipc_set_portimportance(new_ref, msg_importance(msg));
		if (msg_named(msg)) {
			new_tsock->p->conn_type = msg_nametype(msg);
			new_tsock->p->conn_instance = msg_nameinst(msg);
		}

	       /*
		 * Respond to 'SYN-' by discarding it & returning 'ACK'-.
		 * Respond to 'SYN+' by queuing it on new socket.
		 */

		msg_dbg(msg,"<ACC<: ");
		if (!msg_data_sz(msg)) {
			struct msghdr m = {NULL,};

			send_packet(NULL, newsock, &m, 0);
			advance_queue(tsock);
		} else {
			sock_lock(tsock);
			skb_dequeue(&sock->sk->sk_receive_queue);
			sock_unlock(tsock);
			skb_queue_head(&newsock->sk->sk_receive_queue, buf);
		}
	}
exit:
	up(&tsock->sem);
	return res;
}
static int connect(struct socket *sock, struct sockaddr *dest, int destlen, 
		   int flags)
{
   struct tipc_sock *tsock = tipc_sk(sock->sk);
   struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
   struct msghdr m = {0,};
   struct sk_buff *buf;
   struct tipc_msg *msg;
   int res;

   /* For now, TIPC does not allow use of connect() with DGRAM or RDM types */

   if (sock->state == SS_READY)
	   return -EOPNOTSUPP;

   /* MOVE THE REST OF THIS ERROR CHECKING TO send_msg()? */
   if (sock->state == SS_LISTENING)
	   return -EOPNOTSUPP;
   if (sock->state == SS_CONNECTING)
	   return -EALREADY;
   if (sock->state != SS_UNCONNECTED)
           return -EISCONN;

   if ((dst->family != AF_TIPC) ||
       ((dst->addrtype != TIPC_ADDR_NAME) && (dst->addrtype != TIPC_ADDR_ID)))
           return -EINVAL;

   /* Send a 'SYN-' to destination */

   m.msg_name = dest;
   if ((res = send_msg(0, sock, &m, 0)) < 0) {
	   sock->state = SS_DISCONNECTING;
	   return res;
   }

   if (down_interruptible(&tsock->sem)) 
           return -ERESTARTSYS;
	
   /* Wait for destination's 'ACK' response */

   res = wait_event_interruptible_timeout(*sock->sk->sk_sleep,
                                          skb_queue_len(&sock->sk->sk_receive_queue),
					  sock->sk->sk_rcvtimeo);
   buf = skb_peek(&sock->sk->sk_receive_queue);
   if (res > 0) {
	   msg = buf_msg(buf);
           res = auto_connect(sock, tsock, msg);
           if (!res) {
		   if (dst->addrtype == TIPC_ADDR_NAME) {
			   tsock->p->conn_type = dst->addr.name.name.type;
			   tsock->p->conn_instance = dst->addr.name.name.instance;
		   }
		   if (!msg_data_sz(msg))
			   advance_queue(tsock);
	   }
   } else {
	   if (res == 0) {
		   res = -ETIMEDOUT;
	   } else
	           { /* leave "res" unchanged */ }
	   sock->state = SS_DISCONNECTING;
   }

   up(&tsock->sem);
   return res;
}