/*
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
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
- $Id$
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "system.h"
/* RFC 1071 */
-static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
-{
+static uint16_t inet_checksum(void *data, int len, uint16_t prevsum) {
uint16_t *p = data;
uint32_t checksum = prevsum ^ 0xFFFF;
static bool checklength(node_t *source, vpn_packet_t *packet, length_t length) {
if(packet->len < length) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Got too short packet from %s (%s)"), source->name, source->hostname);
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Got too short packet from %s (%s)", source->name, source->hostname);
return false;
} 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 learn_mac(mac_t *address) {
subnet_t *subnet;
avl_node_t *node;
connection_t *c;
- cp();
-
subnet = lookup_subnet_mac(address);
/* 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 %hx:%hx:%hx:%hx:%hx:%hx",
address->x[0], address->x[1], address->x[2], address->x[3],
address->x[4], address->x[5]);
subnet->expires = now + macexpire;
}
-void age_subnets(void)
-{
+void age_subnets(void) {
subnet_t *s;
connection_t *c;
avl_node_t *node, *next, *node2;
- cp();
-
for(node = myself->subnet_tree->head; node; node = next) {
next = node->next;
s = node->data;
ifdebug(TRAFFIC) {
char netstr[MAXNETSTR];
if(net2str(netstr, sizeof netstr, s))
- logger(LOG_INFO, _("Subnet %s expired"), netstr);
+ logger(LOG_INFO, "Subnet %s expired", netstr);
}
for(node2 = connection_tree->head; node2; node2 = node2->next) {
}
}
-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)
-{
+static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, uint8_t type, uint8_t code) {
struct ip ip = {0};
struct icmp icmp = {0};
if(ratelimit(3))
return;
- cp();
+ /* Swap Ethernet source and destination addresses */
+
+ swap_mac_addresses(packet);
/* Copy headers from packet into properly aligned structs on the stack */
uint8_t *offset;
uint16_t ip_off, origf;
- cp();
-
memcpy(&ip, packet->data + ether_size, ip_size);
fragment.priority = packet->priority;
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 (%zd)", packet->len, ether_size + ip_size + todo);
return;
}
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Fragmenting packet of %d bytes to %s (%s)"), packet->len, dest->name, dest->hostname);
+ ifdebug(TRAFFIC) logger(LOG_INFO, "Fragmenting packet of %d bytes to %s (%s)", packet->len, dest->name, dest->hostname);
offset = packet->data + ether_size + ip_size;
maxlen = (dest->mtu - ether_size - ip_size) & ~0x7;
}
}
-static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet)
-{
+static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet) {
subnet_t *subnet;
node_t *via;
ipv4_t dest;
- cp();
-
memcpy(&dest, &packet->data[30], sizeof dest);
subnet = lookup_subnet_ipv4(&dest);
if(!subnet) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet from %s (%s): unknown IPv4 destination address %d.%d.%d.%d"),
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet from %s (%s): unknown IPv4 destination address %d.%d.%d.%d",
source->name, source->hostname,
dest.x[0],
dest.x[1],
}
if(subnet->owner == source) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Packet looping back to %s (%s)!"), source->name, source->hostname);
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Packet looping back to %s (%s)!", source->name, source->hostname);
return;
}
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);
+ 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 = via->mtu;
route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED);
send_packet(subnet->owner, packet);
}
-static void route_ipv4(node_t *source, vpn_packet_t *packet)
-{
- cp();
-
+static void route_ipv4(node_t *source, vpn_packet_t *packet) {
if(!checklength(source, packet, ether_size + ip_size))
return;
/* 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, uint8_t type, uint8_t code) {
struct ip6_hdr ip6;
struct icmp6_hdr icmp6 = {0};
uint16_t checksum;
if(ratelimit(3))
return;
- cp();
+ /* Swap Ethernet source and destination addresses */
+
+ swap_mac_addresses(packet);
/* Copy headers from packet to structs on the stack */
send_packet(source, packet);
}
-static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet)
-{
+static void route_ipv6_unicast(node_t *source, vpn_packet_t *packet) {
subnet_t *subnet;
node_t *via;
ipv6_t dest;
- cp();
-
memcpy(&dest, &packet->data[38], sizeof dest);
subnet = lookup_subnet_ipv6(&dest);
if(!subnet) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet from %s (%s): unknown IPv6 destination address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet from %s (%s): unknown IPv6 destination address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
source->name, source->hostname,
ntohs(dest.x[0]),
ntohs(dest.x[1]),
}
if(subnet->owner == source) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Packet looping back to %s (%s)!"), source->name, source->hostname);
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Packet looping back to %s (%s)!", source->name, source->hostname);
return;
}
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);
+ 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 = via->mtu;
route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0);
return;
/* RFC 2461 */
-static void route_neighborsol(node_t *source, vpn_packet_t *packet)
-{
+static void route_neighborsol(node_t *source, vpn_packet_t *packet) {
struct ip6_hdr ip6;
struct nd_neighbor_solicit ns;
struct nd_opt_hdr opt;
uint32_t next;
} pseudo;
- cp();
-
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);
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Got neighbor solicitation request from %s (%s) while in router mode!", source->name, source->hostname);
return;
}
if(ns.nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
(has_opt && opt.nd_opt_type != ND_OPT_SOURCE_LINKADDR)) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: received unknown type neighbor solicitation request"));
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet: received unknown type neighbor solicitation request");
return;
}
}
if(checksum) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: checksum error for neighbor solicitation request"));
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet: checksum error for neighbor solicitation request");
return;
}
subnet = lookup_subnet_ipv6((ipv6_t *) &ns.nd_ns_target);
if(!subnet) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: neighbor solicitation request for unknown address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet: neighbor solicitation request for unknown address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
ntohs(((uint16_t *) &ns.nd_ns_target)[0]),
ntohs(((uint16_t *) &ns.nd_ns_target)[1]),
ntohs(((uint16_t *) &ns.nd_ns_target)[2]),
send_packet(source, packet);
}
-static void route_ipv6(node_t *source, vpn_packet_t *packet)
-{
- cp();
-
+static void route_ipv6(node_t *source, vpn_packet_t *packet) {
if(!checklength(source, packet, ether_size + ip6_size))
return;
/* RFC 826 */
-static void route_arp(node_t *source, vpn_packet_t *packet)
-{
+static void route_arp(node_t *source, vpn_packet_t *packet) {
struct ether_arp arp;
subnet_t *subnet;
struct in_addr addr;
- cp();
-
if(!checklength(source, packet, ether_size + arp_size))
return;
if(source != myself) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Got ARP request from %s (%s) while in router mode!"), source->name, source->hostname);
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Got ARP request from %s (%s) while in router mode!", source->name, source->hostname);
return;
}
if(ntohs(arp.arp_hrd) != ARPHRD_ETHER || ntohs(arp.arp_pro) != ETH_P_IP ||
arp.arp_hln != ETH_ALEN || arp.arp_pln != sizeof(addr) || ntohs(arp.arp_op) != ARPOP_REQUEST) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: received unknown type ARP request"));
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet: received unknown type ARP request");
return;
}
subnet = lookup_subnet_ipv4((ipv4_t *) &arp.arp_tpa);
if(!subnet) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: ARP request for unknown address %d.%d.%d.%d"),
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet: ARP request for unknown address %d.%d.%d.%d",
arp.arp_tpa[0], arp.arp_tpa[1], arp.arp_tpa[2],
arp.arp_tpa[3]);
return;
send_packet(source, packet);
}
-void route(node_t *source, vpn_packet_t *packet)
-{
- cp();
+static void route_mac(node_t *source, vpn_packet_t *packet) {
+ subnet_t *subnet;
+ mac_t dest;
+
+ /* 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);
+ }
+ return;
+ } else if(type == ETH_P_IPV6) {
+ packet->len = via->mtu;
+ route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0);
+ return;
+ }
+ }
+
+ send_packet(subnet->owner, packet);
+}
+void route(node_t *source, vpn_packet_t *packet) {
if(!checklength(source, packet, ether_size))
return;
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);
break;
default:
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet from %s (%s): unknown type %hx"), source->name, source->hostname, type);
+ ifdebug(TRAFFIC) logger(LOG_WARNING, "Cannot route packet from %s (%s): unknown type %hx", source->name, source->hostname, type);
break;
}
}