incubator-nuttx/net/devif/devif_loopback.c

147 lines
4.1 KiB
C

/****************************************************************************
* net/devif/devif_loopback.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* 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 non-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 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("IPv6 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;
}