nuttx/net/devif/devif_forward.c

/****************************************************************************
 * net/devif/devif_forward.c
 *
 *   Copyright (C) 2017 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. The name of the author may not be used to endorse or promote
 *    products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 <string.h>
#include <assert.h>
#include <debug.h>

#include <nuttx/mm/iob.h>
#include <nuttx/net/netdev.h>

#include "ipforward/ipforward.h"
#include "devif/devif.h"

#ifdef CONFIG_NET_IPFORWARD

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

/****************************************************************************
 * Name: devif_forward
 *
 * Description:
 *   Called from protocol-specific IP forwarding logic to re-send a packet.
 *
 * Input Parameters:
 *   fwd - An initialized instance of the common forwarding structure that
 *         includes everything needed to perform the forwarding operation.
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *   The network is locked.
 *
 ****************************************************************************/

void devif_forward(FAR struct forward_s *fwd)
{
  unsigned int offset;
  int ret;

  DEBUGASSERT(fwd != NULL && fwd->f_iob != NULL && fwd->f_dev != NULL);
  offset = NET_LL_HDRLEN(fwd->f_dev);

  /* Copy the IOB chain that contains the L3L3 headers and any data payload */

  DEBUGASSERT(offset + fwd->f_iob->io_pktlen <= NET_DEV_MTU(fwd->f_dev));
  ret = iob_copyout(&fwd->f_dev->d_buf[offset], fwd->f_iob,
                    fwd->f_iob->io_pktlen, 0);

  DEBUGASSERT(ret == fwd->f_iob->io_pktlen);

  fwd->f_dev->d_sndlen = 0;
  fwd->f_dev->d_len    = fwd->f_iob->io_pktlen;

  UNUSED(ret);
}

#endif /* CONFIG_NET_IPFORWARD */