| /** @file |
| * @brief IPv4 related functions |
| */ |
| |
| /* |
| * Copyright (c) 2016 Intel Corporation |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| #if defined(CONFIG_NET_DEBUG_IPV4) |
| #define SYS_LOG_DOMAIN "net/ipv4" |
| #define NET_LOG_ENABLED 1 |
| #endif |
| |
| #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/tcp.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; |
| |
| /* 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; |
| } |
| |
| void net_ipv4_finalize(struct net_pkt *pkt, u8_t next_header_proto) |
| { |
| /* Set the length of the IPv4 header */ |
| size_t total_len; |
| |
| net_pkt_compact(pkt); |
| |
| total_len = net_pkt_get_len(pkt); |
| |
| NET_IPV4_HDR(pkt)->len = htons(total_len); |
| |
| NET_IPV4_HDR(pkt)->chksum = 0; |
| |
| if (net_if_need_calc_tx_checksum(net_pkt_iface(pkt)) || |
| next_header_proto == IPPROTO_ICMP) { |
| NET_IPV4_HDR(pkt)->chksum = ~net_calc_chksum_ipv4(pkt); |
| |
| if (IS_ENABLED(CONFIG_NET_UDP) && |
| next_header_proto == IPPROTO_UDP) { |
| net_udp_set_chksum(pkt, pkt->frags); |
| } else if (IS_ENABLED(CONFIG_NET_TCP) && |
| next_header_proto == IPPROTO_TCP) { |
| net_tcp_set_chksum(pkt, pkt->frags); |
| } else if (next_header_proto == IPPROTO_ICMP) { |
| net_icmpv4_set_chksum(pkt); |
| } |
| } |
| } |
| |
| 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_process_pkt(struct net_pkt *pkt) |
| { |
| struct net_ipv4_hdr *hdr = NET_IPV4_HDR(pkt); |
| int real_len = net_pkt_get_len(pkt); |
| int pkt_len = ntohs(hdr->len); |
| enum net_verdict verdict = NET_DROP; |
| |
| if (real_len != pkt_len) { |
| NET_DBG("IPv4 packet size %d pkt len %d", pkt_len, real_len); |
| goto drop; |
| } |
| |
| NET_DBG("IPv4 packet received from %s to %s", |
| net_sprint_ipv4_addr(&hdr->src), |
| net_sprint_ipv4_addr(&hdr->dst)); |
| |
| net_pkt_set_ip_hdr_len(pkt, sizeof(struct net_ipv4_hdr)); |
| net_pkt_set_ipv4_ttl(pkt, NET_IPV4_HDR(pkt)->ttl); |
| |
| if (!net_is_my_ipv4_addr(&hdr->dst) && |
| !net_is_ipv4_addr_mcast(&hdr->dst)) { |
| if (IS_ENABLED(CONFIG_NET_DHCPV4) && |
| hdr->proto == IPPROTO_UDP && |
| net_ipv4_addr_cmp(&hdr->dst, |
| net_ipv4_broadcast_address())) { |
| |
| verdict = net_conn_input(IPPROTO_UDP, pkt); |
| if (verdict != NET_DROP) { |
| return verdict; |
| } |
| } |
| |
| NET_DBG("IPv4 packet in pkt %p not for me", pkt); |
| goto drop; |
| } |
| |
| switch (hdr->proto) { |
| case IPPROTO_ICMP: |
| verdict = net_icmpv4_input(pkt); |
| break; |
| case IPPROTO_TCP: |
| case IPPROTO_UDP: |
| verdict = net_conn_input(hdr->proto, pkt); |
| break; |
| } |
| |
| if (verdict != NET_DROP) { |
| return verdict; |
| } |
| |
| drop: |
| net_stats_update_ipv4_drop(net_pkt_iface(pkt)); |
| return NET_DROP; |
| } |