zephyr/drivers/net/loopback.c

103 lines
2.2 KiB
C

/*
* Copyright (c) 2015 Intel Corporation
* Copyright (c) 2017 Linaro Limited
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
*
* Network loopback interface implementation.
*/
#define LOG_MODULE_NAME netlo
#define LOG_LEVEL CONFIG_NET_LOOPBACK_LOG_LEVEL
#include <logging/log.h>
LOG_MODULE_REGISTER(LOG_MODULE_NAME);
#include <net/net_pkt.h>
#include <net/buf.h>
#include <net/net_ip.h>
#include <net/net_if.h>
int loopback_dev_init(struct device *dev)
{
return 0;
}
static void loopback_init(struct net_if *iface)
{
/* RFC 7042, s.2.1.1. address to use in documentation */
net_if_set_link_addr(iface, "\x00\x00\x5e\x00\x53\xff", 6,
NET_LINK_DUMMY);
}
static int loopback_send(struct net_if *iface, struct net_pkt *pkt)
{
struct net_pkt *cloned;
int res;
if (!pkt->frags) {
LOG_ERR("No data to send");
return -ENODATA;
}
/* We need to swap the IP addresses because otherwise
* the packet will be dropped.
*/
if (net_pkt_family(pkt) == AF_INET6) {
struct in6_addr addr;
net_ipaddr_copy(&addr, &NET_IPV6_HDR(pkt)->src);
net_ipaddr_copy(&NET_IPV6_HDR(pkt)->src,
&NET_IPV6_HDR(pkt)->dst);
net_ipaddr_copy(&NET_IPV6_HDR(pkt)->dst, &addr);
} else {
struct in_addr addr;
net_ipaddr_copy(&addr, &NET_IPV4_HDR(pkt)->src);
net_ipaddr_copy(&NET_IPV4_HDR(pkt)->src,
&NET_IPV4_HDR(pkt)->dst);
net_ipaddr_copy(&NET_IPV4_HDR(pkt)->dst, &addr);
}
/* We should simulate normal driver meaning that if the packet is
* properly sent (which is always in this driver), then the packet
* must be dropped. This is very much needed for TCP packets where
* the packet is reference counted in various stages of sending.
*/
cloned = net_pkt_clone(pkt, K_MSEC(100));
if (!cloned) {
res = -ENOMEM;
goto out;
}
res = net_recv_data(iface, cloned);
if (res < 0) {
LOG_ERR("Data receive failed.");
goto out;
}
net_pkt_unref(pkt);
out:
/* Let the receiving thread run now */
k_yield();
return res;
}
static struct net_if_api loopback_if_api = {
.init = loopback_init,
.send = loopback_send,
};
NET_DEVICE_INIT(loopback, "lo",
loopback_dev_init, NULL, NULL,
CONFIG_KERNEL_INIT_PRIORITY_DEFAULT,
&loopback_if_api, DUMMY_L2,
NET_L2_GET_CTX_TYPE(DUMMY_L2), 536);