incubator-nuttx/net/devif/devif_loopback.c

163 lines
4.9 KiB
C

/****************************************************************************
* net/devif/devif_loopback.c
*
* Copyright (C) 2018 Pinecone Inc. All rights reserved.
* Author: Xiang Xiao <xiaoxiang@pinecone.net>
*
* 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 <string.h>
#include <debug.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/pkt.h>
#include <nuttx/net/netdev.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* This is a helper pointer for accessing the contents of the ip header */
#define IPv4BUF ((FAR struct ipv4_hdr_s *)(dev->d_buf + dev->d_llhdrlen))
#define IPv6BUF ((FAR struct ipv6_hdr_s *)(dev->d_buf + dev->d_llhdrlen))
/****************************************************************************
* Private Functions
****************************************************************************/
static bool is_loopback(FAR struct net_driver_s *dev)
{
if (dev->d_len > 0)
{
#ifdef CONFIG_NET_IPv4
if ((IPv4BUF->vhl & IP_VERSION_MASK) == IPv4_VERSION &&
net_ipv4addr_hdrcmp(IPv4BUF->destipaddr, &dev->d_ipaddr))
{
return true;
}
#endif
#ifdef CONFIG_NET_IPv6
if ((IPv6BUF->vtc & IP_VERSION_MASK) == IPv6_VERSION &&
net_ipv6addr_hdrcmp(IPv6BUF->destipaddr, dev->d_ipv6addr))
{
return true;
}
#endif
}
return false;
}
/****************************************************************************
* Name: devif_loopback
*
* Description:
* This function should be called before sending out a packet. The function
* checks the destination address of the packet to see whether the target of
* packet is ourself and then consume the packet directly by calling input
* process functions.
*
* Returned Value:
* Zero is returned if the packet don't loop back to ourself, otherwise
* a no zero value is returned.
*
****************************************************************************/
int devif_loopback(FAR struct net_driver_s *dev)
{
if (!is_loopback(dev))
{
return 0;
}
/* Loop while if there is data "sent" to ourself.
* Sending, of course, just means relaying back through the network.
*/
do
{
NETDEV_TXPACKETS(dev);
NETDEV_RXPACKETS(dev);
#ifdef CONFIG_NET_PKT
/* When packet sockets are enabled, feed the frame into the packet tap */
pkt_input(dev);
#endif
/* We only accept IP packets of the configured type */
#ifdef CONFIG_NET_IPv4
if ((IPv4BUF->vhl & IP_VERSION_MASK) == IPv4_VERSION)
{
ninfo("IPv4 frame\n");
NETDEV_RXIPV4(dev);
ipv4_input(dev);
}
else
#endif
#ifdef CONFIG_NET_IPv6
if ((IPv6BUF->vtc & IP_VERSION_MASK) == IPv6_VERSION)
{
ninfo("Iv6 frame\n");
NETDEV_RXIPV6(dev);
ipv6_input(dev);
}
else
#endif
{
NETDEV_RXDROPPED(dev);
}
NETDEV_TXDONE(dev);
/* Add the link layer header length for the next loop */
if (dev->d_len != 0)
{
dev->d_len += dev->d_llhdrlen;
}
}
while (dev->d_len > 0);
return 1;
}