nuttx/net/uip/uip_mcastmac.c

/****************************************************************************
 * net/uip/uip_mcastmac.c
 *
 *   Copyright (C) 2010 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * The NuttX implementation of IGMP was inspired by the IGMP add-on for the
 * lwIP TCP/IP stack by Steve Reynolds:
 *
 *   Copyright (c) 2002 CITEL Technologies Ltd.
 *   All rights reserved.
 *
 * 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 of CITEL Technologies Ltd 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 CITEL TECHNOLOGIES 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 CITEL TECHNOLOGIES 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 <assert.h>
#include <debug.h>

#include <nuttx/net/uip/uipopt.h>
#include <nuttx/net/uip/uip.h>

#include "uip_internal.h"

#ifdef CONFIG_NET_IGMP

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name:  uip_mcastmac
 *
 * Description:
 *   Given an IP address (in network order), create a IGMP multicast MAC
 *   address.
 *
 ****************************************************************************/

static void uip_mcastmac(uip_ipaddr_t *ip, FAR uint8_t *mac)
{
  /* This mapping is from the IETF IN RFC 1700 */

  mac[0] = 0x01;
  mac[1] = 0x00;
  mac[2] = 0x5e;
  mac[3] = ip4_addr2(*ip) & 0x7f;
  mac[4] = ip4_addr3(*ip);
  mac[5] = ip4_addr4(*ip);

  nvdbg("IP: %08x -> MAC: %02x%02x%02x%02x%02x%02x\n",
        *ip, mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
}

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

/****************************************************************************
 * Name:  uip_addmcastmac
 *
 * Description:
 *   Add an IGMP MAC address to the device's MAC filter table.
 *
 ****************************************************************************/

void uip_addmcastmac(FAR struct uip_driver_s *dev, FAR uip_ipaddr_t *ip)
{
  uint8_t mcastmac[6];

  nvdbg("Adding: IP %08x\n", *ip);
  if (dev->d_addmac)
    {
      uip_mcastmac(ip, mcastmac);
      dev->d_addmac(dev, mcastmac);
    }
}

/****************************************************************************
 * Name:  uip_removemcastmac
 *
 * Description:
 *   Remove an IGMP MAC address from the device's MAC filter table.
 *
 ****************************************************************************/

void uip_removemcastmac(FAR struct uip_driver_s *dev, FAR uip_ipaddr_t *ip)
{
  uint8_t mcastmac[6];

  nvdbg("Removing: IP %08x\n", *ip);
  if (dev->d_rmmac)
    {
      uip_mcastmac(ip, mcastmac);
      dev->d_rmmac(dev, mcastmac);
    }
}

#endif /* CONFIG_NET_IGMP */