/*
route.c -- routing
Copyright (C) 2000-2005 Ivo Timmermans,
- 2000-2006 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2009 Guus Sliepen <guus@tinc-vpn.org>
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
} else
return true;
}
+
+static void swap_mac_addresses(vpn_packet_t *packet) {
+ mac_t tmp;
+ memcpy(&tmp, &packet->data[0], sizeof tmp);
+ memcpy(&packet->data[0], &packet->data[6], sizeof tmp);
+ memcpy(&packet->data[6], &tmp, sizeof tmp);
+}
static void learn_mac(mac_t *address)
{
}
}
-static void route_mac(node_t *source, vpn_packet_t *packet)
-{
- subnet_t *subnet;
- mac_t dest;
-
- cp();
-
-
- /* Learn source address */
-
- if(source == myself) {
- mac_t src;
- memcpy(&src, &packet->data[6], sizeof src);
- learn_mac(&src);
- }
-
- /* Lookup destination address */
-
- memcpy(&dest, &packet->data[0], sizeof dest);
- subnet = lookup_subnet_mac(&dest);
-
- if(!subnet) {
- broadcast_packet(source, packet);
- return;
- }
-
- if(subnet->owner == source) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Packet looping back to %s (%s)!"), source->name, source->hostname);
- return;
- }
-
- send_packet(subnet->owner, packet);
-}
-
/* RFC 792 */
static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t type, uint8_t code)
cp();
+ /* Swap Ethernet source and destination addresses */
+
+ swap_mac_addresses(packet);
+
/* Copy headers from packet into properly aligned structs on the stack */
memcpy(&ip, packet->data + ether_size, ip_size);
if(!checklength(source, packet, ether_size + ip_size))
return;
- route_ipv4_unicast(source, packet);
+ if(((packet->data[30] & 0xf0) == 0xe0) || (
+ packet->data[30] == 255 &&
+ packet->data[31] == 255 &&
+ packet->data[32] == 255 &&
+ packet->data[33] == 255))
+ broadcast_packet(source, packet);
+ else
+ route_ipv4_unicast(source, packet);
}
/* RFC 2463 */
cp();
+ /* Swap Ethernet source and destination addresses */
+
+ swap_mac_addresses(packet);
+
/* Copy headers from packet to structs on the stack */
memcpy(&ip6, packet->data + ether_size, ip6_size);
struct nd_opt_hdr opt;
subnet_t *subnet;
uint16_t checksum;
+ bool has_opt;
struct {
struct in6_addr ip6_src; /* source address */
cp();
- if(!checklength(source, packet, ether_size + ip6_size + ns_size + opt_size + ETH_ALEN))
+ if(!checklength(source, packet, ether_size + ip6_size + ns_size))
return;
+ has_opt = packet->len >= ether_size + ip6_size + ns_size + opt_size + ETH_ALEN;
+
if(source != myself) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Got neighbor solicitation request from %s (%s) while in router mode!"), source->name, source->hostname);
return;
memcpy(&ip6, packet->data + ether_size, ip6_size);
memcpy(&ns, packet->data + ether_size + ip6_size, ns_size);
- memcpy(&opt, packet->data + ether_size + ip6_size + ns_size, opt_size);
+ if(has_opt)
+ memcpy(&opt, packet->data + ether_size + ip6_size + ns_size, opt_size);
/* First, snatch the source address from the neighbor solicitation packet */
/* Check if this is a valid neighbor solicitation request */
if(ns.nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
- opt.nd_opt_type != ND_OPT_SOURCE_LINKADDR) {
+ (has_opt && opt.nd_opt_type != ND_OPT_SOURCE_LINKADDR)) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: received unknown type neighbor solicitation request"));
return;
}
pseudo.ip6_src = ip6.ip6_src;
pseudo.ip6_dst = ip6.ip6_dst;
- pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
+ if(has_opt)
+ pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
+ else
+ pseudo.length = htonl(ns_size);
pseudo.next = htonl(IPPROTO_ICMPV6);
/* Generate checksum */
checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
checksum = inet_checksum(&ns, ns_size, checksum);
- checksum = inet_checksum(&opt, opt_size, checksum);
- checksum = inet_checksum(packet->data + ether_size + ip6_size + ns_size + opt_size, ETH_ALEN, checksum);
+ if(has_opt) {
+ checksum = inet_checksum(&opt, opt_size, checksum);
+ checksum = inet_checksum(packet->data + ether_size + ip6_size + ns_size + opt_size, ETH_ALEN, checksum);
+ }
if(checksum) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: checksum error for neighbor solicitation request"));
ip6.ip6_dst = ip6.ip6_src; /* swap destination and source protocoll address */
ip6.ip6_src = ns.nd_ns_target;
- memcpy(packet->data + ether_size + ip6_size + ns_size + opt_size, packet->data + ETH_ALEN, ETH_ALEN); /* add fake source hard addr */
+ if(has_opt)
+ memcpy(packet->data + ether_size + ip6_size + ns_size + opt_size, packet->data + ETH_ALEN, ETH_ALEN); /* add fake source hard addr */
ns.nd_ns_cksum = 0;
ns.nd_ns_type = ND_NEIGHBOR_ADVERT;
pseudo.ip6_src = ip6.ip6_src;
pseudo.ip6_dst = ip6.ip6_dst;
- pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
+ if(has_opt)
+ pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
+ else
+ pseudo.length = htonl(ns_size);
pseudo.next = htonl(IPPROTO_ICMPV6);
/* Generate checksum */
checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
checksum = inet_checksum(&ns, ns_size, checksum);
- checksum = inet_checksum(&opt, opt_size, checksum);
- checksum = inet_checksum(packet->data + ether_size + ip6_size + ns_size + opt_size, ETH_ALEN, checksum);
+ if(has_opt) {
+ checksum = inet_checksum(&opt, opt_size, checksum);
+ checksum = inet_checksum(packet->data + ether_size + ip6_size + ns_size + opt_size, ETH_ALEN, checksum);
+ }
ns.nd_ns_hdr.icmp6_cksum = checksum;
memcpy(packet->data + ether_size, &ip6, ip6_size);
memcpy(packet->data + ether_size + ip6_size, &ns, ns_size);
- memcpy(packet->data + ether_size + ip6_size + ns_size, &opt, opt_size);
+ if(has_opt)
+ memcpy(packet->data + ether_size + ip6_size + ns_size, &opt, opt_size);
send_packet(source, packet);
}
return;
}
- route_ipv6_unicast(source, packet);
+ if(packet->data[38] == 255)
+ broadcast_packet(source, packet);
+ else
+ route_ipv6_unicast(source, packet);
}
/* RFC 826 */
send_packet(source, packet);
}
+static void route_mac(node_t *source, vpn_packet_t *packet)
+{
+ subnet_t *subnet;
+ mac_t dest;
+
+ cp();
+
+
+ /* Learn source address */
+
+ if(source == myself) {
+ mac_t src;
+ memcpy(&src, &packet->data[6], sizeof src);
+ learn_mac(&src);
+ }
+
+ /* Lookup destination address */
+
+ memcpy(&dest, &packet->data[0], sizeof dest);
+ subnet = lookup_subnet_mac(&dest);
+
+ if(!subnet) {
+ broadcast_packet(source, packet);
+ return;
+ }
+
+ if(subnet->owner == source) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Packet looping back to %s (%s)!"), source->name, source->hostname);
+ return;
+ }
+
+ // Handle packets larger than PMTU
+
+ node_t *via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
+
+ 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) {
+ if(packet->data[20] & 0x40) {
+ packet->len = via->mtu;
+ route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED);
+ } else {
+ fragment_ipv4_packet(via, packet);
+ }
+ } else if(type == ETH_P_IPV6) {
+ packet->len = via->mtu;
+ route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0);
+ } else
+ ifdebug(TRAFFIC) logger(LOG_INFO, _("Large packet of unhandled type %hx dropped"), type);
+
+ return;
+ }
+
+ send_packet(subnet->owner, packet);
+}
+
+
void route(node_t *source, vpn_packet_t *packet)
{
cp();
switch (routing_mode) {
case RMODE_ROUTER:
{
- uint16_t type;
+ uint16_t type = packet->data[12] << 8 | packet->data[13];
- type = ntohs(*((uint16_t *)(&packet->data[12])));
switch (type) {
case ETH_P_ARP:
route_arp(source, packet);
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