/**************************************************************************** * net/tcp/tcp_connect.c * * Copyright (C) 2007-2012, 2015-2017 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * 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. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "devif/devif.h" #include "socket/socket.h" #include "tcp/tcp.h" #ifdef NET_TCP_HAVE_STACK /**************************************************************************** * Private Types ****************************************************************************/ struct tcp_connect_s { FAR struct tcp_conn_s *tc_conn; /* Reference to TCP connection structure */ FAR struct devif_callback_s *tc_cb; /* Reference to callback instance */ FAR struct socket *tc_psock; /* The socket being connected */ sem_t tc_sem; /* Semaphore signals recv completion */ int tc_result; /* OK on success, otherwise a negated errno. */ }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static inline int psock_setup_callbacks(FAR struct socket *psock, FAR struct tcp_connect_s *pstate); static void psock_teardown_callbacks(FAR struct tcp_connect_s *pstate, int status); static uint16_t psock_connect_eventhandler(FAR struct net_driver_s *dev, FAR void *pvconn, FAR void *pvpriv, uint16_t flags); /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: psock_setup_callbacks ****************************************************************************/ static inline int psock_setup_callbacks(FAR struct socket *psock, FAR struct tcp_connect_s *pstate) { FAR struct tcp_conn_s *conn = psock->s_conn; int ret = -EBUSY; /* Initialize the TCP state structure */ /* This semaphore is used for signaling and, hence, should not have * priority inheritance enabled. */ (void)nxsem_init(&pstate->tc_sem, 0, 0); /* Doesn't really fail */ (void)nxsem_setprotocol(&pstate->tc_sem, SEM_PRIO_NONE); pstate->tc_conn = conn; pstate->tc_psock = psock; pstate->tc_result = -EAGAIN; /* Set up the callbacks in the connection */ pstate->tc_cb = tcp_callback_alloc(conn); if (pstate->tc_cb) { /* Set up the connection event handler */ pstate->tc_cb->flags = (TCP_NEWDATA | TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT | TCP_CONNECTED | NETDEV_DOWN); pstate->tc_cb->priv = (FAR void *)pstate; pstate->tc_cb->event = psock_connect_eventhandler; ret = OK; } return ret; } /**************************************************************************** * Name: psock_teardown_callbacks ****************************************************************************/ static void psock_teardown_callbacks(FAR struct tcp_connect_s *pstate, int status) { FAR struct tcp_conn_s *conn = pstate->tc_conn; /* Make sure that no further events are processed */ tcp_callback_free(conn, pstate->tc_cb); pstate->tc_cb = NULL; /* If we successfully connected, we will continue to monitor the connection * state via callbacks. */ if (status < 0) { /* Failed to connect. Stop the connection event monitor */ tcp_stop_monitor(conn, TCP_CLOSE); } } /**************************************************************************** * Name: psock_connect_eventhandler * * Description: * This function is called to perform the actual connection operation via * by the lower, device interfacing layer. * * Parameters: * dev The structure of the network driver that reported the event * pvconn The connection structure associated with the socket * flags Set of events describing why the callback was invoked * * Returned Value: * The new flags setting * * Assumptions: * The network is locked. * ****************************************************************************/ static uint16_t psock_connect_eventhandler(FAR struct net_driver_s *dev, FAR void *pvconn, FAR void *pvpriv, uint16_t flags) { struct tcp_connect_s *pstate = (struct tcp_connect_s *)pvpriv; ninfo("flags: %04x\n", flags); /* 'priv' might be null in some race conditions (?) */ if (pstate) { /* The following errors should be detected here (someday) * * ECONNREFUSED * No one listening on the remote address. * ENETUNREACH * Network is unreachable. * ETIMEDOUT * Timeout while attempting connection. The server may be too busy * to accept new connections. */ /* TCP_CLOSE: The remote host has closed the connection * TCP_ABORT: The remote host has aborted the connection */ if ((flags & (TCP_CLOSE | TCP_ABORT)) != 0) { /* Indicate that remote host refused the connection */ pstate->tc_result = -ECONNREFUSED; } /* TCP_TIMEDOUT: Connection aborted due to too many retransmissions. */ else if ((flags & TCP_TIMEDOUT) != 0) { /* Indicate that the connection timedout?) */ pstate->tc_result = -ETIMEDOUT; } else if ((flags & NETDEV_DOWN) != 0) { /* The network device went down. Indicate that the remote host * is unreachable. */ pstate->tc_result = -ENETUNREACH; } /* TCP_CONNECTED: The socket is successfully connected */ else if ((flags & TCP_CONNECTED) != 0) { FAR struct socket *psock = pstate->tc_psock; DEBUGASSERT(psock); /* Mark the connection bound and connected. NOTE this is * is done here (vs. later) in order to avoid any race condition * in the socket state. It is known to connected here and now, * but not necessarily at any time later. */ psock->s_flags |= (_SF_BOUND | _SF_CONNECTED); /* Indicate that the socket is no longer connected */ pstate->tc_result = OK; } /* Otherwise, it is not an event of importance to us at the moment */ else { /* Drop data received in this state */ dev->d_len = 0; return flags & ~TCP_NEWDATA; } ninfo("Resuming: %d\n", pstate->tc_result); /* Stop further callbacks */ psock_teardown_callbacks(pstate, pstate->tc_result); /* When we set up the connection structure, we did not know the size * of the initial MSS. Now that the connection is associated with a * network device, we now know the size of link layer header and can * determine the correct initial MSS. */ DEBUGASSERT(pstate->tc_conn); #ifdef CONFIG_NET_IPv4 #ifdef CONFIG_NET_IPv6 if (pstate->tc_conn->domain == PF_INET) #endif { pstate->tc_conn->mss = TCP_IPv4_INITIAL_MSS(dev); } #endif /* CONFIG_NET_IPv4 */ #ifdef CONFIG_NET_IPv6 #ifdef CONFIG_NET_IPv4 else #endif { pstate->tc_conn->mss = TCP_IPv6_INITIAL_MSS(dev); } #endif /* CONFIG_NET_IPv6 */ /* We now have to filter all outgoing transfers so that they use only * the MSS of this device. */ DEBUGASSERT(pstate->tc_conn->dev == NULL || pstate->tc_conn->dev == dev); pstate->tc_conn->dev = dev; /* Wake up the waiting thread */ nxsem_post(&pstate->tc_sem); } return flags; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: psock_tcp_connect * * Description: * Perform a TCP connection * * Parameters: * psock - A reference to the socket structure of the socket to be connected * addr - The address of the remote server to connect to * * Returned Value: * None * * Assumptions: * The network is locked * ****************************************************************************/ int psock_tcp_connect(FAR struct socket *psock, FAR const struct sockaddr *addr) { struct tcp_connect_s state; int ret = OK; /* Interrupts must be disabled through all of the following because * we cannot allow the network callback to occur until we are completely * setup. */ net_lock(); /* Get the connection reference from the socket */ if (!psock->s_conn) /* Should always be non-NULL */ { ret = -EINVAL; } else { /* Perform the TCP connection operation */ ret = tcp_connect(psock->s_conn, addr); } if (ret >= 0) { /* Set up the callbacks in the connection */ ret = psock_setup_callbacks(psock, &state); if (ret >= 0) { /* Wait for either the connect to complete or for an error/timeout * to occur. NOTES: net_lockedwait will also terminate if a signal * is received. */ ret = net_lockedwait(&state.tc_sem); /* Uninitialize the state structure */ (void)nxsem_destroy(&state.tc_sem); /* If net_lockedwait failed, negated errno was returned. */ if (ret >= 0) { /* If the wait succeeded, then get the new error value from * the state structure */ ret = state.tc_result; } /* Make sure that no further events are processed */ psock_teardown_callbacks(&state, ret); } /* Check if the socket was successfully connected. */ if (ret >= 0) { /* Yes... Now that we are connected, we need to set up to monitor * the state of the connection up the connection event monitor. */ ret = tcp_start_monitor(psock); if (ret < 0) { /* tcp_start_monitor() can only fail on certain race * conditions where the connection was lost just before * this function was called. That is not expected to * happen in this context, but just in case... */ tcp_stop_monitor(psock->s_conn, TCP_ABORT); } } } net_unlock(); return ret; } #endif /* NET_TCP_HAVE_STACK */