bartoszek/zephyr
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
79dc1feeb3
zephyr/subsys/net/ip/ipv4.c
Tomasz Bursztyka 21c66a8fe1 net/ipv4: Handle options relevantly 
IPv4 header might come with options, unlike IPv6, these are not
encapsulated in option header but are fully part of the IPv4 header.

Zephyr must handles these. Now silently ignoring their content and
setting the cursor to the payload properly.

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
2019-03-11 20:57:29 -07:00

274 lines
6.6 KiB
C
Raw Blame History

/** @file
* @brief IPv4 related functions
*/
/*
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <logging/log.h>
LOG_MODULE_REGISTER(net_ipv4, CONFIG_NET_IPV4_LOG_LEVEL);
#include <errno.h>
#include <net/net_core.h>
#include <net/net_pkt.h>
#include <net/net_stats.h>
#include <net/net_context.h>
#include "net_private.h"
#include "connection.h"
#include "net_stats.h"
#include "icmpv4.h"
#include "udp_internal.h"
#include "tcp_internal.h"
#include "ipv4.h"
/* Timeout for various buffer allocations in this file. */
#define NET_BUF_TIMEOUT K_MSEC(50)
struct net_pkt *net_ipv4_create(struct net_pkt *pkt,
const struct in_addr *src,
const struct in_addr *dst,
struct net_if *iface,
u8_t next_header_proto)
{
struct net_buf *header;
header = net_pkt_get_frag(pkt, NET_BUF_TIMEOUT);
if (!header) {
return NULL;
}
net_pkt_frag_insert(pkt, header);
NET_IPV4_HDR(pkt)->vhl = 0x45;
NET_IPV4_HDR(pkt)->tos = 0x00;
NET_IPV4_HDR(pkt)->proto = next_header_proto;
NET_IPV4_HDR(pkt)->chksum = 0;
/* User can tweak the default TTL if needed */
NET_IPV4_HDR(pkt)->ttl = net_pkt_ipv4_ttl(pkt);
if (NET_IPV4_HDR(pkt)->ttl == 0) {
NET_IPV4_HDR(pkt)->ttl = net_if_ipv4_get_ttl(iface);
}
NET_IPV4_HDR(pkt)->offset[0] = NET_IPV4_HDR(pkt)->offset[1] = 0;
NET_IPV4_HDR(pkt)->id[0] = NET_IPV4_HDR(pkt)->id[1] = 0;
net_ipaddr_copy(&NET_IPV4_HDR(pkt)->dst, dst);
net_ipaddr_copy(&NET_IPV4_HDR(pkt)->src, src);
net_pkt_set_ip_hdr_len(pkt, sizeof(struct net_ipv4_hdr));
net_pkt_set_family(pkt, AF_INET);
net_buf_add(header, sizeof(struct net_ipv4_hdr));
return pkt;
}
int net_ipv4_create_new(struct net_pkt *pkt,
const struct in_addr *src,
const struct in_addr *dst)
{
NET_PKT_DATA_ACCESS_CONTIGUOUS_DEFINE(ipv4_access, struct net_ipv4_hdr);
struct net_ipv4_hdr *ipv4_hdr;
ipv4_hdr = (struct net_ipv4_hdr *)net_pkt_get_data_new(pkt,
&ipv4_access);
if (!ipv4_hdr) {
return -ENOBUFS;
}
ipv4_hdr->vhl = 0x45;
ipv4_hdr->tos = 0x00;
ipv4_hdr->len = 0;
ipv4_hdr->id[0] = 0;
ipv4_hdr->id[1] = 0;
ipv4_hdr->offset[0] = 0;
ipv4_hdr->offset[1] = 0;
ipv4_hdr->ttl = net_pkt_ipv4_ttl(pkt);
if (ipv4_hdr->ttl == 0) {
ipv4_hdr->ttl = net_if_ipv4_get_ttl(net_pkt_iface(pkt));
}
ipv4_hdr->proto = 0;
ipv4_hdr->chksum = 0;
net_ipaddr_copy(&ipv4_hdr->dst, dst);
net_ipaddr_copy(&ipv4_hdr->src, src);
net_pkt_set_ip_hdr_len(pkt, sizeof(struct net_ipv4_hdr));
return net_pkt_set_data(pkt, &ipv4_access);
}
int net_ipv4_finalize(struct net_pkt *pkt, u8_t next_header_proto)
{
NET_PKT_DATA_ACCESS_CONTIGUOUS_DEFINE(ipv4_access, struct net_ipv4_hdr);
struct net_ipv4_hdr *ipv4_hdr;
net_pkt_set_overwrite(pkt, true);
ipv4_hdr = (struct net_ipv4_hdr *)net_pkt_get_data_new(pkt,
&ipv4_access);
if (!ipv4_hdr) {
return -ENOBUFS;
}
ipv4_hdr->len = htons(net_pkt_get_len(pkt));
ipv4_hdr->proto = next_header_proto;
if (net_if_need_calc_tx_checksum(net_pkt_iface(pkt)) ||
next_header_proto == IPPROTO_ICMP) {
ipv4_hdr->chksum = net_calc_chksum_ipv4(pkt);
net_pkt_set_data(pkt, &ipv4_access);
if (IS_ENABLED(CONFIG_NET_UDP) &&
next_header_proto == IPPROTO_UDP) {
return net_udp_finalize(pkt);
} else if (IS_ENABLED(CONFIG_NET_TCP) &&
next_header_proto == IPPROTO_TCP) {
return net_tcp_finalize(pkt);
} else if (next_header_proto == IPPROTO_ICMP) {
return net_icmpv4_finalize(pkt);
}
}
return net_pkt_set_data(pkt, &ipv4_access);
}
const struct in_addr *net_ipv4_unspecified_address(void)
{
static const struct in_addr addr;
return &addr;
}
const struct in_addr *net_ipv4_broadcast_address(void)
{
static const struct in_addr addr = { { { 255, 255, 255, 255 } } };
return &addr;
}
enum net_verdict net_ipv4_input(struct net_pkt *pkt)
{
NET_PKT_DATA_ACCESS_CONTIGUOUS_DEFINE(ipv4_access, struct net_ipv4_hdr);
NET_PKT_DATA_ACCESS_DEFINE(udp_access, struct net_udp_hdr);
NET_PKT_DATA_ACCESS_DEFINE(tcp_access, struct net_tcp_hdr);
int real_len = net_pkt_get_len(pkt);
enum net_verdict verdict = NET_DROP;
union net_proto_header proto_hdr;
struct net_ipv4_hdr *hdr;
union net_ip_header ip;
u8_t hdr_len;
int pkt_len;
net_stats_update_ipv4_recv(net_pkt_iface(pkt));
hdr = (struct net_ipv4_hdr *)net_pkt_get_data_new(pkt, &ipv4_access);
if (!hdr) {
NET_DBG("DROP: no buffer");
goto drop;
}
hdr_len = (hdr->vhl & NET_IPV4_IHL_MASK) * 4;
if (hdr_len < sizeof(struct net_ipv4_hdr)) {
NET_DBG("DROP: Invalid hdr length");
goto drop;
}
net_pkt_set_ip_hdr_len(pkt, hdr_len);
pkt_len = ntohs(hdr->len);
if (real_len < pkt_len) {
NET_DBG("DROP: pkt len per hdr %d != pkt real len %d",
pkt_len, real_len);
goto drop;
} else if (real_len > pkt_len) {
net_pkt_update_length(pkt, pkt_len);
}
if (net_ipv4_is_addr_mcast(&hdr->src)) {
NET_DBG("DROP: src addr is mcast");
goto drop;
}
if (net_ipv4_is_addr_bcast(net_pkt_iface(pkt), &hdr->src)) {
NET_DBG("DROP: src addr is bcast");
goto drop;
}
if (net_if_need_calc_rx_checksum(net_pkt_iface(pkt)) &&
net_calc_chksum_ipv4(pkt) != 0) {
NET_DBG("DROP: invalid chksum");
goto drop;
}
if (!net_ipv4_is_my_addr(&hdr->dst) &&
!net_ipv4_is_addr_mcast(&hdr->dst) &&
((hdr->proto == IPPROTO_UDP &&
net_ipv4_addr_cmp(&hdr->dst, net_ipv4_broadcast_address()) &&
!IS_ENABLED(CONFIG_NET_DHCPV4)) ||
(hdr->proto == IPPROTO_TCP &&
net_ipv4_is_addr_bcast(net_pkt_iface(pkt), &hdr->dst)))) {
NET_DBG("DROP: not for me");
goto drop;
}
net_pkt_acknowledge_data(pkt, &ipv4_access);
if (hdr_len > sizeof(struct net_ipv4_hdr)) {
/* There are probably options, let's skip them */
if (net_pkt_skip(pkt, hdr_len - sizeof(struct net_ipv4_hdr))) {
NET_DBG("Header too big? %u", hdr_len);
goto drop;
}
}
net_pkt_set_ipv4_ttl(pkt, hdr->ttl);
net_pkt_set_family(pkt, PF_INET);
NET_DBG("IPv4 packet received from %s to %s",
log_strdup(net_sprint_ipv4_addr(&hdr->src)),
log_strdup(net_sprint_ipv4_addr(&hdr->dst)));
switch (hdr->proto) {
case IPPROTO_ICMP:
verdict = net_icmpv4_input(pkt, hdr);
break;
case IPPROTO_TCP:
proto_hdr.tcp = net_tcp_input(pkt, &tcp_access);
if (proto_hdr.tcp) {
verdict = NET_OK;
}
break;
case IPPROTO_UDP:
proto_hdr.udp = net_udp_input(pkt, &udp_access);
if (proto_hdr.udp) {
verdict = NET_OK;
}
break;
}
if (verdict == NET_DROP) {
goto drop;
} else if (hdr->proto == IPPROTO_ICMP) {
return verdict;
}
ip.ipv4 = hdr;
verdict = net_conn_input(pkt, &ip, hdr->proto, &proto_hdr);
if (verdict != NET_DROP) {
return verdict;
}
drop:
net_stats_update_ipv4_drop(net_pkt_iface(pkt));
return NET_DROP;
}
Reference in New Issue View Git Blame Copy Permalink