/****************************************************************************
* net/tcp/tcp_setsockopt.c
*
* Copyright (C) 2018 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/time.h>
#include <stdint.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <netinet/tcp.h>
#include <nuttx/net/net.h>
#include <nuttx/net/tcp.h>
#include "socket/socket.h"
#include "utils/utils.h"
#include "tcp/tcp.h"
#ifdef CONFIG_NET_TCPPROTO_OPTIONS
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tcp_getsockopt
*
* Description:
* tcp_getsockopt() retrieves the value for the option specified by the
* 'option' argument for the socket specified by the 'psock' argument. If
* the size of the option value is greater than 'value_len', the value
* stored in the object pointed to by the 'value' argument will be silently
* truncated. Otherwise, the length pointed to by the 'value_len' argument
* will be modified to indicate the actual length of the 'value'.
*
* The 'level' argument specifies the protocol level of the option. To
* retrieve options at the socket level, specify the level argument as
* SOL_SOCKET; to retrieve options at the TCP-protocol level, the level
* argument is SOL_CP.
*
* See <sys/socket.h> a complete list of values for the socket-level
* 'option' argument. Protocol-specific options are are protocol specific
* header files (such as netinet/tcp.h for the case of the TCP protocol).
*
* Input Parameters:
* psock Socket structure of the socket to query
* level Protocol level to set the option
* option identifies the option to get
* value Points to the argument value
* value_len The length of the argument value
*
* Returned Value:
* Returns zero (OK) on success. On failure, it returns a negated errno
* value to indicate the nature of the error. See psock_getsockopt() for
* the complete list of appropriate return error codes.
*
****************************************************************************/
int tcp_getsockopt(FAR struct socket *psock, int option,
FAR void *value, FAR socklen_t *value_len)
{
#ifdef CONFIG_NET_TCP_KEEPALIVE
/* Keep alive options are the only TCP protocol socket option currently
* supported.
*/
FAR struct tcp_conn_s *conn;
int ret;
DEBUGASSERT(psock != NULL && value != NULL && value_len != NULL &&
psock->s_conn != NULL);
conn = (FAR struct tcp_conn_s *)psock->s_conn;
/* All of the TCP protocol options apply only TCP sockets. The sockets
* do not have to be connected.. that might occur later with the KeepAlive
* already configured.
*/
if (psock->s_type != SOCK_STREAM)
{
nerr("ERROR: Not a TCP socket\n");
return -ENOTCONN;
}
/* Handle the Keep-Alive option */
switch (option)
{
/* Handle the SO_KEEPALIVE socket-level option.
*
* NOTE: SO_KEEPALIVE is not really a socket-level option; it is a
* protocol-level option. A given TCP connection may service multiple
* sockets (via dup'ing of the socket). There is, however, still only
* one connection to be monitored and that is a global attribute across
* all of the clones that may use the underlying connection.
*/
case SO_KEEPALIVE: /* Verifies TCP connections active by enabling the
* periodic transmission of probes */
if (*value_len < sizeof(int))
{
/* REVISIT: POSIX says that we should truncate the value if it
* is larger than value_len. That just doesn't make sense
* to me in this case.
*/
ret = -EINVAL;
}
else
{
FAR int *keepalive = (FAR int *)value;
*keepalive = (int)conn->keepalive;
*value_len = sizeof(int);
ret = OK;
}
break;
case TCP_NODELAY: /* Avoid coalescing of small segments. */
nerr("ERROR: TCP_NODELAY not supported\n");
ret = -ENOSYS;
break;
case TCP_KEEPIDLE: /* Start keepalives after this IDLE period */
if (*value_len < sizeof(struct timeval))
{
/* REVISIT: POSIX says that we should truncate the value if it
* is larger than value_len. That just doesn't make sense
* to me in this case.
*/
ret = -EINVAL;
}
else
{
FAR struct timeval *tv = (FAR struct timeval *)value;
if (tv == NULL)
{
ret = -EINVAL;
}
else
{
/* Convert the KeepIdle time from deciseconds to struct
* timeval.
*/
net_dsec2timeval(conn->keepidle, tv);
*value_len = sizeof(struct timeval);
ret = OK;
}
}
break;
case TCP_KEEPINTVL: /* Interval between keepalives */
if (*value_len < sizeof(struct timeval))
{
/* REVISIT: POSIX says that we should truncate the value if it
* is larger than value_len. That just doesn't make sense
* to me in this case.
*/
ret = -EINVAL;
}
else
{
FAR struct timeval *tv = (FAR struct timeval *)value;
if (tv == NULL)
{
ret = -EINVAL;
}
else
{
/* Convert the KeepIdle time from deciseconds to struct
* timeval.
*/
net_dsec2timeval(conn->keepintvl, tv);
*value_len = sizeof(struct timeval);
ret = OK;
}
}
break;
case TCP_KEEPCNT: /* Number of keepalives before death */
if (*value_len < sizeof(int))
{
/* REVISIT: POSIX says that we should truncate the value if it
* is larger than value_len. That just doesn't make sense
* to me in this case.
*/
ret = -EINVAL;
}
else
{
FAR int *keepcnt = (FAR int *)value;
*keepcnt = (int)conn->keepcnt;
*value_len = sizeof(int);
ret = OK;
}
break;
default:
nerr("ERROR: Unrecognized TCP option: %d\n", option);
ret = -ENOPROTOOPT;
break;
}
return ret;
#else
return -ENOPROTOOPT;
#endif /* CONFIG_NET_TCP_KEEPALIVE */
}
#endif /* CONFIG_NET_TCPPROTO_OPTIONS */