X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Froute.c;h=e196f44873854b75a882638ed1f5bd546a1ffc39;hp=6eadb888162980633a2813e0da199092c61987ff;hb=c9c3cc03bfec664f7386011f3fc608d1c0844836;hpb=b5e3bf1a85462f0c41638c11305d28f87af24395 diff --git a/src/route.c b/src/route.c index 6eadb888..e196f448 100644 --- a/src/route.c +++ b/src/route.c @@ -1,7 +1,7 @@ /* route.c -- routing Copyright (C) 2000-2005 Ivo Timmermans, - 2000-2012 Guus Sliepen + 2000-2013 Guus Sliepen This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -34,12 +34,12 @@ rmode_t routing_mode = RMODE_ROUTER; fmode_t forwarding_mode = FMODE_INTERNAL; +bmode_t broadcast_mode = BMODE_MST; bool decrement_ttl = false; bool directonly = false; bool priorityinheritance = false; int macexpire = 600; bool overwrite_mac = false; -bool broadcast = true; mac_t mymac = {{0xFE, 0xFD, 0, 0, 0, 0}}; /* Sizes of various headers */ @@ -110,15 +110,22 @@ static void clamp_mss(const node_t *source, const node_t *via, vpn_packet_t *pac mtu = via->mtu; /* Find TCP header */ - int start = 0; + int start = ether_size; uint16_t type = packet->data[12] << 8 | packet->data[13]; - if(type == ETH_P_IP && packet->data[23] == 6) - start = 14 + (packet->data[14] & 0xf) * 4; - else if(type == ETH_P_IPV6 && packet->data[20] == 6) - start = 14 + 40; + if(type == ETH_P_8021Q) { + start += 4; + type = packet->data[16] << 8 | packet->data[17]; + } + + if(type == ETH_P_IP && packet->data[start + 9] == 6) + start += (packet->data[start] & 0xf) * 4; + else if(type == ETH_P_IPV6 && packet->data[start + 6] == 6) + start += 40; + else + return; - if(!start || packet->len <= start + 20) + if(packet->len <= start + 20) return; /* Use data offset field to calculate length of options field */ @@ -244,7 +251,7 @@ void age_subnets(void) { /* RFC 792 */ -static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t type, uint8_t code) { +static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, length_t ether_size, uint8_t type, uint8_t code) { struct ip ip = {0}; struct icmp icmp = {0}; @@ -317,7 +324,7 @@ static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t /* RFC 791 */ -static void fragment_ipv4_packet(node_t *dest, vpn_packet_t *packet) { +static void fragment_ipv4_packet(node_t *dest, vpn_packet_t *packet, length_t ether_size) { struct ip ip; vpn_packet_t fragment; int len, maxlen, todo; @@ -333,7 +340,7 @@ static void fragment_ipv4_packet(node_t *dest, vpn_packet_t *packet) { todo = ntohs(ip.ip_len) - ip_size; if(ether_size + ip_size + todo != packet->len) { - ifdebug(TRAFFIC) logger(LOG_WARNING, "Length of packet (%d) doesn't match length in IPv4 header (%zd)", packet->len, ether_size + ip_size + todo); + ifdebug(TRAFFIC) logger(LOG_WARNING, "Length of packet (%d) doesn't match length in IPv4 header (%d)", packet->len, (int)(ether_size + ip_size + todo)); return; } @@ -381,7 +388,7 @@ static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet) { dest.x[2], dest.x[3]); - route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_UNKNOWN); + route_ipv4_unreachable(source, packet, ether_size, ICMP_DEST_UNREACH, ICMP_NET_UNKNOWN); return; } @@ -391,10 +398,10 @@ static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet) { } if(!subnet->owner->status.reachable) - return route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_UNREACH); + return route_ipv4_unreachable(source, packet, ether_size, ICMP_DEST_UNREACH, ICMP_NET_UNREACH); if(forwarding_mode == FMODE_OFF && source != myself && subnet->owner != myself) - return route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_ANO); + return route_ipv4_unreachable(source, packet, ether_size, ICMP_DEST_UNREACH, ICMP_NET_ANO); if(priorityinheritance) packet->priority = packet->data[15]; @@ -407,15 +414,15 @@ static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet) { } if(directonly && subnet->owner != via) - return route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_ANO); + return route_ipv4_unreachable(source, packet, ether_size, ICMP_DEST_UNREACH, ICMP_NET_ANO); if(via && packet->len > MAX(via->mtu, 590) && via != myself) { ifdebug(TRAFFIC) logger(LOG_INFO, "Packet for %s (%s) length %d larger than MTU %d", subnet->owner->name, subnet->owner->hostname, packet->len, via->mtu); if(packet->data[20] & 0x40) { packet->len = MAX(via->mtu, 590); - route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED); + route_ipv4_unreachable(source, packet, ether_size, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED); } else { - fragment_ipv4_packet(via, packet); + fragment_ipv4_packet(via, packet, ether_size); } return; @@ -430,7 +437,7 @@ static void route_ipv4(node_t *source, vpn_packet_t *packet) { if(!checklength(source, packet, ether_size + ip_size)) return; - if(broadcast && (((packet->data[30] & 0xf0) == 0xe0) || ( + if(broadcast_mode && (((packet->data[30] & 0xf0) == 0xe0) || ( packet->data[30] == 255 && packet->data[31] == 255 && packet->data[32] == 255 && @@ -442,7 +449,7 @@ static void route_ipv4(node_t *source, vpn_packet_t *packet) { /* RFC 2463 */ -static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, uint8_t type, uint8_t code) { +static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, length_t ether_size, uint8_t type, uint8_t code) { struct ip6_hdr ip6; struct icmp6_hdr icmp6 = {0}; uint16_t checksum; @@ -540,7 +547,7 @@ static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet) { ntohs(dest.x[6]), ntohs(dest.x[7])); - route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADDR); + route_ipv6_unreachable(source, packet, ether_size, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADDR); return; } @@ -550,10 +557,10 @@ static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet) { } if(!subnet->owner->status.reachable) - return route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOROUTE); + return route_ipv6_unreachable(source, packet, ether_size, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOROUTE); if(forwarding_mode == FMODE_OFF && source != myself && subnet->owner != myself) - return route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADMIN); + return route_ipv6_unreachable(source, packet, ether_size, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADMIN); via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via; @@ -563,12 +570,12 @@ static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet) { } if(directonly && subnet->owner != via) - return route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADMIN); + return route_ipv6_unreachable(source, packet, ether_size, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADMIN); if(via && packet->len > MAX(via->mtu, 1294) && via != myself) { ifdebug(TRAFFIC) logger(LOG_INFO, "Packet for %s (%s) length %d larger than MTU %d", subnet->owner->name, subnet->owner->hostname, packet->len, via->mtu); packet->len = MAX(via->mtu, 1294); - route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0); + route_ipv6_unreachable(source, packet, ether_size, ICMP6_PACKET_TOO_BIG, 0); return; } @@ -727,7 +734,7 @@ static void route_ipv6(node_t *source, vpn_packet_t *packet) { return; } - if(broadcast && packet->data[38] == 255) + if(broadcast_mode && packet->data[38] == 255) broadcast_packet(source, packet); else route_ipv6_unicast(source, packet); @@ -817,8 +824,7 @@ static void route_mac(node_t *source, vpn_packet_t *packet) { subnet = lookup_subnet_mac(NULL, &dest); if(!subnet) { - if(broadcast) - broadcast_packet(source, packet); + broadcast_packet(source, packet); return; } @@ -830,6 +836,11 @@ static void route_mac(node_t *source, vpn_packet_t *packet) { if(forwarding_mode == FMODE_OFF && source != myself && subnet->owner != myself) return; + uint16_t type = packet->data[12] << 8 | packet->data[13]; + + if(priorityinheritance && type == ETH_P_IP && packet->len >= ether_size + ip_size) + packet->priority = packet->data[15]; + // Handle packets larger than PMTU node_t *via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via; @@ -839,18 +850,24 @@ static void route_mac(node_t *source, vpn_packet_t *packet) { if(via && packet->len > via->mtu && via != myself) { ifdebug(TRAFFIC) logger(LOG_INFO, "Packet for %s (%s) length %d larger than MTU %d", subnet->owner->name, subnet->owner->hostname, packet->len, via->mtu); - uint16_t type = packet->data[12] << 8 | packet->data[13]; - if(type == ETH_P_IP && packet->len > 590) { - if(packet->data[20] & 0x40) { + length_t ethlen = 14; + + if(type == ETH_P_8021Q) { + type = packet->data[16] << 8 | packet->data[17]; + ethlen += 4; + } + + if(type == ETH_P_IP && packet->len > 576 + ethlen) { + if(packet->data[6 + ethlen] & 0x40) { packet->len = via->mtu; - route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED); + route_ipv4_unreachable(source, packet, ethlen, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED); } else { - fragment_ipv4_packet(via, packet); + fragment_ipv4_packet(via, packet, ethlen); } return; - } else if(type == ETH_P_IPV6 && packet->len > 1294) { + } else if(type == ETH_P_IPV6 && packet->len > 1280 + ethlen) { packet->len = via->mtu; - route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0); + route_ipv6_unreachable(source, packet, ethlen, ICMP6_PACKET_TOO_BIG, 0); return; } } @@ -862,42 +879,48 @@ static void route_mac(node_t *source, vpn_packet_t *packet) { static bool do_decrement_ttl(node_t *source, vpn_packet_t *packet) { uint16_t type = packet->data[12] << 8 | packet->data[13]; + length_t ethlen = ether_size; + + if(type == ETH_P_8021Q) { + type = packet->data[16] << 8 | packet->data[17]; + ethlen += 4; + } switch (type) { case ETH_P_IP: - if(!checklength(source, packet, 14 + 32)) + if(!checklength(source, packet, ethlen + ip_size)) return false; - if(packet->data[22] < 1) { - if(packet->data[25] != IPPROTO_ICMP || packet->data[46] != ICMP_TIME_EXCEEDED) - route_ipv4_unreachable(source, packet, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL); + if(packet->data[ethlen + 8] < 1) { + if(packet->data[ethlen + 11] != IPPROTO_ICMP || packet->data[ethlen + 32] != ICMP_TIME_EXCEEDED) + route_ipv4_unreachable(source, packet, ethlen, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL); return false; } - uint16_t old = packet->data[22] << 8 | packet->data[23]; - packet->data[22]--; - uint16_t new = packet->data[22] << 8 | packet->data[23]; + uint16_t old = packet->data[ethlen + 8] << 8 | packet->data[ethlen + 9]; + packet->data[ethlen + 8]--; + uint16_t new = packet->data[ethlen + 8] << 8 | packet->data[ethlen + 9]; - uint32_t checksum = packet->data[24] << 8 | packet->data[25]; + uint32_t checksum = packet->data[ethlen + 10] << 8 | packet->data[ethlen + 11]; checksum += old + (~new & 0xFFFF); while(checksum >> 16) checksum = (checksum & 0xFFFF) + (checksum >> 16); - packet->data[24] = checksum >> 8; - packet->data[25] = checksum & 0xff; + packet->data[ethlen + 10] = checksum >> 8; + packet->data[ethlen + 11] = checksum & 0xff; return true; case ETH_P_IPV6: - if(!checklength(source, packet, 14 + 40)) + if(!checklength(source, packet, ethlen + ip6_size)) return false; - if(packet->data[21] < 1) { - if(packet->data[20] != IPPROTO_ICMPV6 || packet->data[54] != ICMP6_TIME_EXCEEDED) - route_ipv6_unreachable(source, packet, ICMP6_TIME_EXCEEDED, ICMP6_TIME_EXCEED_TRANSIT); + if(packet->data[ethlen + 7] < 1) { + if(packet->data[ethlen + 6] != IPPROTO_ICMPV6 || packet->data[ethlen + 40] != ICMP6_TIME_EXCEEDED) + route_ipv6_unreachable(source, packet, ethlen, ICMP6_TIME_EXCEEDED, ICMP6_TIME_EXCEED_TRANSIT); return false; } - packet->data[21]--; + packet->data[ethlen + 7]--; return true;