/****************************************************************************
* net/tcp/tcp_accept.c
*
* Copyright (C) 2007-2012, 2015-2016 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>
#ifdef CONFIG_NET_TCP
#include <sys/types.h>
#include <sys/socket.h>
#include <semaphore.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/semaphore.h>
#include <nuttx/net/net.h>
#include "socket/socket.h"
#include "tcp/tcp.h"
/****************************************************************************
* Private Types
****************************************************************************/
struct accept_s
{
FAR struct socket *acpt_sock; /* The accepting socket */
sem_t acpt_sem; /* Wait for driver event */
FAR struct sockaddr *acpt_addr; /* Return connection address */
FAR socklen_t *acpt_addrlen; /* Return length of address */
FAR struct tcp_conn_s *acpt_newconn; /* The accepted connection */
int acpt_result; /* The result of the wait */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: accept_tcpsender
*
* Description:
* Get the sender's address from the UDP packet
*
* Input Parameters:
* psock - The state structure of the accepting socket
* conn - The newly accepted TCP connection
* pstate - the recvfrom state structure
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked
*
****************************************************************************/
#ifdef CONFIG_NET_TCP
static inline void accept_tcpsender(FAR struct socket *psock,
FAR struct tcp_conn_s *conn,
FAR struct sockaddr *addr,
socklen_t *addrlen)
{
if (addr)
{
/* If an address is provided, then the length must also be provided. */
DEBUGASSERT(addrlen);
#ifdef CONFIG_NET_IPv4
#ifdef CONFIG_NET_IPv6
/* If both IPv4 and IPv6 support are enabled, then we will need to
* select which one to use when obtaining the sender's IP address.
*/
if (psock->s_domain == PF_INET)
#endif /* CONFIG_NET_IPv6 */
{
FAR struct sockaddr_in *inaddr = (FAR struct sockaddr_in *)addr;
inaddr->sin_family = AF_INET;
inaddr->sin_port = conn->rport;
net_ipv4addr_copy(inaddr->sin_addr.s_addr, conn->u.ipv4.raddr);
*addrlen = sizeof(struct sockaddr_in);
}
#endif /* CONFIG_NET_IPv4 */
#ifdef CONFIG_NET_IPv6
#ifdef CONFIG_NET_IPv4
/* Otherwise, this the IPv6 address is needed */
else
#endif /* CONFIG_NET_IPv4 */
{
FAR struct sockaddr_in6 *inaddr = (FAR struct sockaddr_in6 *)addr;
DEBUGASSERT(psock->s_domain == PF_INET6);
inaddr->sin6_family = AF_INET6;
inaddr->sin6_port = conn->rport;
net_ipv6addr_copy(inaddr->sin6_addr.s6_addr, conn->u.ipv6.raddr);
*addrlen = sizeof(struct sockaddr_in6);
}
#endif /* CONFIG_NET_IPv6 */
}
}
#endif /* CONFIG_NET_TCP */
/****************************************************************************
* Name: accept_eventhandler
*
* Description:
* Receive event callbacks when connections occur
*
* Input Parameters:
* listener The connection structure of the listener
* conn The connection structure that was just accepted
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked
*
****************************************************************************/
static int accept_eventhandler(FAR struct tcp_conn_s *listener,
FAR struct tcp_conn_s *conn)
{
struct accept_s *pstate = (struct accept_s *)listener->accept_private;
int ret = -EINVAL;
if (pstate)
{
/* Get the connection address */
accept_tcpsender(pstate->acpt_sock, conn, pstate->acpt_addr,
pstate->acpt_addrlen);
/* Save the connection structure */
pstate->acpt_newconn = conn;
pstate->acpt_result = OK;
/* There should be a reference of one on the new connection */
DEBUGASSERT(conn->crefs == 1);
/* Wake-up the waiting caller thread */
nxsem_post(&pstate->acpt_sem);
/* Stop any further callbacks */
listener->accept_private = NULL;
listener->accept = NULL;
ret = OK;
}
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tcp_accept
*
* Description:
* This function implements accept() for TCP/IP sockets. See the
* description of accept() for further information.
*
* Input Parameters:
* psock The listening TCP socket structure
* addr Receives the address of the connecting client
* addrlen Input: allocated size of 'addr', Return: returned size of
* 'addr'
* newconn The new, accepted TCP connection structure
*
* Returned Value:
* Returns zero (OK) on success or a negated errno value on failure.
* See the description of accept of the possible errno values in the
* description of accept().
*
* Assumptions:
* Network is locked.
*
****************************************************************************/
int psock_tcp_accept(FAR struct socket *psock, FAR struct sockaddr *addr,
FAR socklen_t *addrlen, FAR void **newconn)
{
FAR struct tcp_conn_s *conn;
struct accept_s state;
int ret;
DEBUGASSERT(psock && newconn);
/* Check the backlog to see if there is a connection already pending for
* this listener.
*/
conn = (FAR struct tcp_conn_s *)psock->s_conn;
#ifdef CONFIG_NET_TCPBACKLOG
state.acpt_newconn = tcp_backlogremove(conn);
if (state.acpt_newconn)
{
/* Yes... get the address of the connected client */
ninfo("Pending conn=%p\n", state.acpt_newconn);
accept_tcpsender(psock, state.acpt_newconn, addr, addrlen);
}
/* In general, this implementation will not support non-blocking socket
* operations... except in a few cases: Here for TCP accept with
* backlog enabled. If this socket is configured as non-blocking then
* return EAGAIN if there is no pending connection in the backlog.
*/
else if (_SS_ISNONBLOCK(psock->s_flags))
{
return -EAGAIN;
}
else
#endif
{
/* Set the socket state to accepting */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_ACCEPT);
/* Perform the TCP accept operation */
/* Initialize the state structure. This is done with the network
* locked because we don't want anything to happen until we are
* ready.
*/
state.acpt_sock = psock;
state.acpt_addr = addr;
state.acpt_addrlen = addrlen;
state.acpt_newconn = NULL;
state.acpt_result = OK;
/* This semaphore is used for signaling and, hence, should not have
* priority inheritance enabled.
*/
nxsem_init(&state.acpt_sem, 0, 0);
nxsem_setprotocol(&state.acpt_sem, SEM_PRIO_NONE);
/* Set up the callback in the connection */
conn->accept_private = (FAR void *)&state;
conn->accept = accept_eventhandler;
/* Wait for the send to complete or an error to occur: NOTES:
* net_lockedwait will also terminate if a signal is received.
*/
ret = net_lockedwait(&state.acpt_sem);
/* Make sure that no further events are processed */
conn->accept_private = NULL;
conn->accept = NULL;
nxsem_destroy(&state. acpt_sem);
/* Set the socket state to idle */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_IDLE);
/* Check for a errors. Errors are signalled by negative errno values
* for the send length.
*/
if (state.acpt_result != 0)
{
DEBUGASSERT(state.acpt_result > 0);
return -state.acpt_result;
}
/* If net_lockedwait failed, then we were probably reawakened by a
* signal. In this case, net_lockedwait will have returned negated
* errno appropriately.
*/
if (ret < 0)
{
return ret;
}
}
*newconn = (FAR void *)state.acpt_newconn;
return OK;
}
#endif /* CONFIG_NET_TCP */