nuttx/net/socket/getsockopt.c
2020-01-31 13:45:15 -06:00

456 lines
16 KiB
C

/****************************************************************************
* net/socket/getsockopt.c
*
* Copyright (C) 2007-2009, 2012, 2014, 2017-2019 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>
#if defined(CONFIG_NET) && defined(CONFIG_NET_SOCKOPTS)
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <debug.h>
#include <assert.h>
#include <errno.h>
#include "socket/socket.h"
#include "tcp/tcp.h"
#include "usrsock/usrsock.h"
#include "utils/utils.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: psock_socketlevel_option
*
* Description:
* getsockopt() retrieve 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.
*
****************************************************************************/
static int psock_socketlevel_option(FAR struct socket *psock, int option,
FAR void *value, FAR socklen_t *value_len)
{
/* Verify that the socket option if valid (but might not be supported ) */
if (!_SO_GETVALID(option) || !value || !value_len)
{
return -EINVAL;
}
#ifdef CONFIG_NET_USRSOCK
if (psock->s_type == SOCK_USRSOCK_TYPE)
{
FAR struct usrsock_conn_s *conn = psock->s_conn;
DEBUGASSERT(conn);
/* Some of the socket options are handled from this function. */
switch (option)
{
case SO_TYPE: /* Type can be read from NuttX psock structure. */
case SO_RCVTIMEO: /* Rx timeouts can be handled at NuttX side, thus
* simplify daemon implementation. */
case SO_SNDTIMEO: /* Rx timeouts can be handled at NuttX side, thus
* simplify daemon implementation. */
break;
default: /* Other options are passed to usrsock daemon. */
{
return usrsock_getsockopt(conn, SOL_SOCKET, option, value, value_len);
}
}
}
#endif
/* Process the option */
switch (option)
{
case SO_ACCEPTCONN: /* Reports whether socket listening is enabled */
if (*value_len < sizeof(int))
{
return -EINVAL;
}
*(FAR int *)value = _SS_ISLISTENING(psock->s_flags);
*value_len = sizeof(int);
break;
/* The following options take a point to an integer boolean value.
* We will blindly report the bit here although the implementation
* is outside of the scope of getsockopt.
*/
case SO_BROADCAST: /* Permits sending of broadcast messages */
case SO_DEBUG: /* Enables recording of debugging information */
case SO_DONTROUTE: /* Requests outgoing messages bypass standard routing */
#ifndef CONFIG_NET_TCPPROTO_OPTIONS
case SO_KEEPALIVE: /* Verifies TCP connections active by enabling the
* periodic transmission of probes */
#endif
case SO_OOBINLINE: /* Leaves received out-of-band data inline */
case SO_REUSEADDR: /* Allow reuse of local addresses */
{
sockopt_t optionset;
/* Verify that option is the size of an 'int'. Should also check
* that 'value' is properly aligned for an 'int'
*/
if (*value_len < sizeof(int))
{
return -EINVAL;
}
/* Sample the current options. This is atomic operation and so
* should not require any special steps for thread safety. We
* this outside of the macro because you can never be sure what
* a macro will do.
*/
optionset = psock->s_options;
*(FAR int *)value = _SO_GETOPT(optionset, option);
*value_len = sizeof(int);
}
break;
#ifdef CONFIG_NET_TCPPROTO_OPTIONS
/* Any connection-oriented protocol could potentially support
* SO_KEEPALIVE. However, this option is currently only available for
* TCP/IP.
*
* 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 */
return tcp_getsockopt(psock, option, value, value_len);
#endif
case SO_TYPE: /* Reports the socket type */
{
/* Verify that option is the size of an 'int'. Should also check
* that 'value' is properly aligned for an 'int'
*/
if (*value_len < sizeof(int))
{
return -EINVAL;
}
#ifdef CONFIG_NET_USRSOCK
if (psock->s_type == SOCK_USRSOCK_TYPE)
{
FAR struct usrsock_conn_s *conn = psock->s_conn;
/* Return the actual socket type */
*(FAR int *)value = conn->type;
*value_len = sizeof(int);
break;
}
#endif
/* Return the socket type */
*(FAR int *)value = psock->s_type;
*value_len = sizeof(int);
}
break;
/* The following are valid only if the OS CLOCK feature is enabled */
case SO_RCVTIMEO:
case SO_SNDTIMEO:
{
socktimeo_t timeo;
/* Verify that option is the size of an 'int'. Should also check
* that 'value' is properly aligned for an 'int'
*/
if (*value_len < sizeof(struct timeval))
{
return -EINVAL;
}
/* Get the timeout value. This is a atomic operation and should
* require no special operation.
*/
if (option == SO_RCVTIMEO)
{
timeo = psock->s_rcvtimeo;
}
else
{
timeo = psock->s_sndtimeo;
}
/* Then return the timeout value to the caller */
net_dsec2timeval(timeo, (struct timeval *)value);
*value_len = sizeof(struct timeval);
}
break;
case SO_ERROR: /* Reports and clears error status. */
{
if (*value_len != sizeof(int))
{
return -EINVAL;
}
*(FAR int *)value = (int)psock->s_error;
psock->s_error = 0;
}
break;
/* The following are not yet implemented (return values other than {0,1) */
case SO_LINGER: /* Lingers on a close() if data is present */
case SO_RCVBUF: /* Sets receive buffer size */
case SO_RCVLOWAT: /* Sets the minimum number of bytes to input */
case SO_SNDBUF: /* Sets send buffer size */
case SO_SNDLOWAT: /* Sets the minimum number of bytes to output */
default:
return -ENOPROTOOPT;
}
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: psock_getsockopt
*
* Description:
* getsockopt() retrieve 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.
*
* EINVAL
* The specified option is invalid at the specified socket 'level' or the
* socket has been shutdown.
* ENOPROTOOPT
* The 'option' is not supported by the protocol.
* ENOTSOCK
* The 'psock' argument does not refer to a socket.
* ENOBUFS
* Insufficient resources are available in the system to complete the
* call.
*
****************************************************************************/
int psock_getsockopt(FAR struct socket *psock, int level, int option,
FAR void *value, FAR socklen_t *value_len)
{
int ret;
/* Verify that the sockfd corresponds to valid, allocated socket */
if (psock == NULL || psock->s_crefs <= 0)
{
return -EBADF;
}
/* Handle retrieval of the socket option according to the level at which
* option should be applied.
*/
switch (level)
{
case SOL_SOCKET: /* Socket-level options (see include/sys/socket.h) */
ret = psock_socketlevel_option(psock, option, value, value_len);
break;
case SOL_TCP: /* TCP protocol socket options (see include/netinet/tcp.h) */
#ifdef CONFIG_NET_TCPPROTO_OPTIONS
ret = tcp_getsockopt(psock, option, value, value_len);
break;
#endif
/* These levels are defined in sys/socket.h, but are not yet
* implemented.
*/
case SOL_IP: /* TCP protocol socket options (see include/netinet/ip.h) */
case SOL_IPV6: /* TCP protocol socket options (see include/netinet/ip6.h) */
case SOL_UDP: /* TCP protocol socket options (see include/netinit/udp.h) */
ret = -ENOSYS;
break;
default: /* The provided level is invalid */
ret = -EINVAL;
break;
}
return ret;
}
/****************************************************************************
* Name: getsockopt
*
* Description:
* getsockopt() retrieve the value for the option specified by the
* 'option' argument for the socket specified by the 'sockfd' 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:
* sockfd Socket descriptor of socket
* 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, -1 (ERROR) is returned and th
* errno variable is set appropriately:
*
* EBADF
* The 'sockfd' argument is not a valid socket descriptor.
* EINVAL
* The specified option is invalid at the specified socket 'level' or the
* socket has been shutdown.
* ENOPROTOOPT
* The 'option' is not supported by the protocol.
* ENOTSOCK
* The 'sockfd' argument does not refer to a socket.
* ENOBUFS
* Insufficient resources are available in the system to complete the
* call.
*
****************************************************************************/
int getsockopt(int sockfd, int level, int option, void *value, socklen_t *value_len)
{
FAR struct socket *psock;
int ret;
/* Get the underlying socket structure */
psock = sockfd_socket(sockfd);
/* Then let psock_getsockopt() do all of the work */
ret = psock_getsockopt(psock, level, option, value, value_len);
if (ret < 0)
{
_SO_SETERRNO(psock, -ret);
return ERROR;
}
return OK;
}
#endif /* CONFIG_NET && CONFIG_NET_SOCKOPTS */