| /** @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/nbuf.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 "ipv4.h" |
| |
| struct net_buf *net_ipv4_create_raw(struct net_buf *buf, |
| const struct in_addr *src, |
| const struct in_addr *dst, |
| struct net_if *iface, |
| uint8_t next_header) |
| { |
| struct net_buf *header; |
| |
| header = net_nbuf_get_frag(buf, K_FOREVER); |
| |
| net_buf_frag_insert(buf, header); |
| |
| NET_IPV4_BUF(buf)->vhl = 0x45; |
| NET_IPV4_BUF(buf)->tos = 0x00; |
| NET_IPV4_BUF(buf)->proto = 0; |
| |
| NET_IPV4_BUF(buf)->ttl = net_if_ipv4_get_ttl(iface); |
| NET_IPV4_BUF(buf)->offset[0] = NET_IPV4_BUF(buf)->offset[1] = 0; |
| NET_IPV4_BUF(buf)->id[0] = NET_IPV4_BUF(buf)->id[1] = 0; |
| |
| net_ipaddr_copy(&NET_IPV4_BUF(buf)->dst, dst); |
| net_ipaddr_copy(&NET_IPV4_BUF(buf)->src, src); |
| |
| NET_IPV4_BUF(buf)->proto = next_header; |
| |
| net_nbuf_set_ip_hdr_len(buf, sizeof(struct net_ipv4_hdr)); |
| net_nbuf_set_family(buf, AF_INET); |
| |
| net_buf_add(header, sizeof(struct net_ipv4_hdr)); |
| |
| return buf; |
| } |
| |
| struct net_buf *net_ipv4_create(struct net_context *context, |
| struct net_buf *buf, |
| const struct in_addr *src, |
| const struct in_addr *dst) |
| { |
| NET_ASSERT(((struct sockaddr_in_ptr *)&context->local)->sin_addr); |
| |
| if (!src) { |
| src = ((struct sockaddr_in_ptr *)&context->local)->sin_addr; |
| } |
| |
| if (net_is_ipv4_addr_unspecified(src) |
| || net_is_ipv4_addr_mcast(src)) { |
| src = &net_nbuf_iface(buf)->ipv4.unicast[0].address.in_addr; |
| } |
| |
| return net_ipv4_create_raw(buf, |
| src, |
| dst, |
| net_context_get_iface(context), |
| net_context_get_ip_proto(context)); |
| } |
| |
| int net_ipv4_finalize_raw(struct net_buf *buf, uint8_t next_header) |
| { |
| /* Set the length of the IPv4 header */ |
| size_t total_len; |
| |
| net_nbuf_compact(buf); |
| |
| total_len = net_buf_frags_len(buf->frags); |
| |
| NET_IPV4_BUF(buf)->len[0] = total_len / 256; |
| NET_IPV4_BUF(buf)->len[1] = total_len - NET_IPV4_BUF(buf)->len[0] * 256; |
| |
| NET_IPV4_BUF(buf)->chksum = 0; |
| NET_IPV4_BUF(buf)->chksum = ~net_calc_chksum_ipv4(buf); |
| |
| #if defined(CONFIG_NET_UDP) |
| if (next_header == IPPROTO_UDP) { |
| NET_UDP_BUF(buf)->chksum = 0; |
| NET_UDP_BUF(buf)->chksum = ~net_calc_chksum_udp(buf); |
| } |
| #endif |
| #if defined(CONFIG_NET_TCP) |
| if (next_header == IPPROTO_TCP) { |
| NET_TCP_BUF(buf)->chksum = 0; |
| NET_TCP_BUF(buf)->chksum = ~net_calc_chksum_tcp(buf); |
| } |
| #endif |
| |
| return 0; |
| } |
| |
| int net_ipv4_finalize(struct net_context *context, struct net_buf *buf) |
| { |
| return net_ipv4_finalize_raw(buf, |
| net_context_get_ip_proto(context)); |
| } |
| |
| 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; |
| } |
| |
| static inline enum net_verdict process_icmpv4_pkt(struct net_buf *buf, |
| struct net_ipv4_hdr *ipv4) |
| { |
| struct net_icmp_hdr *hdr = NET_ICMP_BUF(buf); |
| |
| NET_DBG("ICMPv4 packet received type %d code %d", |
| hdr->type, hdr->code); |
| |
| return net_icmpv4_input(buf, hdr->type, hdr->code); |
| } |
| |
| enum net_verdict net_ipv4_process_pkt(struct net_buf *buf) |
| { |
| struct net_ipv4_hdr *hdr = NET_IPV4_BUF(buf); |
| int real_len = net_buf_frags_len(buf); |
| int pkt_len = (hdr->len[0] << 8) + hdr->len[1]; |
| enum net_verdict verdict = NET_DROP; |
| |
| if (real_len != pkt_len) { |
| NET_DBG("IPv4 packet size %d buf len %d", pkt_len, real_len); |
| goto drop; |
| } |
| |
| #if defined(CONFIG_NET_DEBUG_IPV4) |
| do { |
| char out[sizeof("xxx.xxx.xxx.xxx")]; |
| |
| snprintk(out, sizeof(out), "%s", |
| net_sprint_ipv4_addr(&hdr->dst)); |
| NET_DBG("IPv4 packet received from %s to %s", |
| net_sprint_ipv4_addr(&hdr->src), out); |
| } while (0); |
| #endif /* CONFIG_NET_DEBUG_IPV4 */ |
| |
| net_nbuf_set_ip_hdr_len(buf, sizeof(struct net_ipv4_hdr)); |
| |
| if (!net_is_my_ipv4_addr(&hdr->dst)) { |
| #if defined(CONFIG_NET_DHCPV4) |
| if (hdr->proto == IPPROTO_UDP && |
| net_ipv4_addr_cmp(&hdr->dst, |
| net_ipv4_broadcast_address())) { |
| |
| verdict = net_conn_input(IPPROTO_UDP, buf); |
| if (verdict != NET_DROP) { |
| return verdict; |
| } |
| } |
| #endif |
| NET_DBG("IPv4 packet in buf %p not for me", buf); |
| goto drop; |
| } |
| |
| switch (hdr->proto) { |
| case IPPROTO_ICMP: |
| verdict = process_icmpv4_pkt(buf, hdr); |
| break; |
| case IPPROTO_UDP: |
| verdict = net_conn_input(IPPROTO_UDP, buf); |
| break; |
| case IPPROTO_TCP: |
| verdict = net_conn_input(IPPROTO_TCP, buf); |
| break; |
| } |
| |
| if (verdict != NET_DROP) { |
| return verdict; |
| } |
| |
| drop: |
| net_stats_update_ipv4_drop(); |
| return NET_DROP; |
| } |