/*
route.c -- routing
Copyright (C) 2000-2005 Ivo Timmermans,
- 2000-2010 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2014 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
rmode_t routing_mode = RMODE_ROUTER;
fmode_t forwarding_mode = FMODE_INTERNAL;
-bool decrement_ttl = true;
+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 */
static int count = 0;
if(lasttime == now) {
- if(++count > frequency)
+ if(count >= frequency)
return true;
} else {
lasttime = now;
count = 0;
}
+ count++;
return false;
}
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 */
/* If we don't know this MAC address yet, store it */
if(!subnet) {
- ifdebug(TRAFFIC) logger(LOG_INFO, "Learned new MAC address %hx:%hx:%hx:%hx:%hx:%hx",
+ ifdebug(TRAFFIC) logger(LOG_INFO, "Learned new MAC address %x:%x:%x:%x:%x:%x",
address->x[0], address->x[1], address->x[2], address->x[3],
address->x[4], address->x[5]);
/* 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};
/* 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;
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;
}
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;
}
}
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];
via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
+
+ if(via == source) {
+ ifdebug(TRAFFIC) logger(LOG_ERR, "Routing loop for packet from %s (%s)!", source->name, source->hostname);
+ return;
+ }
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;
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 &&
/* 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;
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;
}
}
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;
+ if(via == source) {
+ ifdebug(TRAFFIC) logger(LOG_ERR, "Routing loop for packet from %s (%s)!", source->name, source->hostname);
+ return;
+ }
+
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;
}
return;
}
- if(broadcast && packet->data[38] == 255)
+ if(broadcast_mode && packet->data[38] == 255)
broadcast_packet(source, packet);
else
route_ipv6_unicast(source, packet);
subnet = lookup_subnet_mac(NULL, &dest);
if(!subnet) {
- if(broadcast)
- broadcast_packet(source, packet);
+ broadcast_packet(source, packet);
return;
}
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;
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;
}
}
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) {
- 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) {
- 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;