nuttx-apps/netutils/netlib/netlib_getmacaddr.c

/****************************************************************************
 * netutils/netlib/netlib_getmacaddr.c
 *
 *   Copyright (C) 2007-2009, 2011 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) && CONFIG_NSOCKET_DESCRIPTORS > 0

#include <sys/socket.h>
#include <sys/ioctl.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

#include <netinet/in.h>
#include <net/if.h>

#include "netutils/netlib.h"

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/
/* The address family that we used to create the socket really does not
 * matter.  It should, however, be valid in the current configuration.
 */

#if defined(CONFIG_NET_IPv4)
#  define PF_INETX PF_INET
#elif defined(CONFIG_NET_IPv6)
#  define PF_INETX PF_INET6
#endif

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: netlib_getmacaddr
 *
 * Description:
 *   Get the network driver IP address
 *
 * Parameters:
 *   ifname   The name of the interface to use
 *   macaddr  The location to return the MAC address
 *
 * Return:
 *   0 on success; -1 on failure
 *
 ****************************************************************************/

int netlib_getmacaddr(const char *ifname, uint8_t *macaddr)
{
  int ret = ERROR;
  if (ifname && macaddr)
    {
      /* Get a socket (only so that we get access to the INET subsystem) */

      int sockfd = socket(PF_INETX, NETLIB_SOCK_IOCTL, 0);
      if (sockfd >= 0)
        {
          struct ifreq req;
          memset (&req, 0, sizeof(struct ifreq));

          /* Put the driver name into the request */

          strncpy(req.ifr_name, ifname, IFNAMSIZ);

          /* Perform the ioctl to get the MAC address */

          ret = ioctl(sockfd, SIOCGIFHWADDR, (unsigned long)&req);
          if (!ret)
            {
              /* Return the MAC address */

              memcpy(macaddr, &req.ifr_hwaddr.sa_data, IFHWADDRLEN);
            }
          close(sockfd);
        }
    }
  return ret;
}

#endif /* CONFIG_NET && CONFIG_NSOCKET_DESCRIPTORS */