incubator-nuttx/net/tcp/tcp_connect.c

393 lines
12 KiB
C

/****************************************************************************
* net/tcp/tcp_connect.c
*
* Copyright (C) 2007-2012, 2015-2017 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <nuttx/config.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <stdint.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <arch/irq.h>
#include <nuttx/semaphore.h>
#include <nuttx/net/net.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/udp.h>
#include <nuttx/net/tcp.h>
#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.
*/
nxsem_init(&pstate->tc_sem, 0, 0); /* Doesn't really fail */
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.
*
* Input 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);
/* We now have to filter all outgoing transfers so that they use only
* the MSS of this device.
*/
DEBUGASSERT(pstate->tc_conn != NULL);
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
*
* Input 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 */
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 */