/*
route.c -- routing
- Copyright (C) 2000-2003 Ivo Timmermans <ivo@o2w.nl>,
- 2000-2003 Guus Sliepen <guus@sliepen.eu.org>
+ Copyright (C) 2000-2005 Ivo Timmermans <ivo@tinc-vpn.org>,
+ 2000-2005 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
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- $Id: route.c,v 1.1.2.73 2003/12/20 21:25:17 guus Exp $
+ $Id$
*/
#include "system.h"
-#ifdef HAVE_NET_ETHERNET_H
-#include <net/ethernet.h>
-#endif
-#ifdef HAVE_NET_IF_ARP_H
-#include <net/if_arp.h>
-#endif
-#ifdef HAVE_NETINET_IP_ICMP_H
-#include <netinet/ip_icmp.h>
-#endif
-#ifdef HAVE_NETINET_ICMP6_H
-#include <netinet/icmp6.h>
-#endif
-#ifdef HAVE_NETINET_IF_ETHER_H
-#include <netinet/if_ether.h>
-#endif
-
#include "avl_tree.h"
#include "connection.h"
#include "ethernet.h"
/* RFC 1071 */
-static __inline__ 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;
return ~checksum;
}
-static __inline__ bool ratelimit(int frequency) {
+static bool ratelimit(int frequency) {
static time_t lasttime = 0;
static int count = 0;
return false;
}
-static __inline__ bool checklength(node_t *source, vpn_packet_t *packet, length_t length) {
+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);
return false;
return true;
}
-static __inline__ void learn_mac(mac_t *address)
+static void learn_mac(mac_t *address)
{
subnet_t *subnet;
avl_node_t *node;
}
}
-static __inline__ void route_mac(node_t *source, vpn_packet_t *packet)
+static void route_mac(node_t *source, vpn_packet_t *packet)
{
subnet_t *subnet;
send_packet(source, packet);
}
-static __inline__ void route_ipv4_unicast(node_t *source, vpn_packet_t *packet)
+/* RFC 791 */
+
+static void fragment_ipv4_packet(node_t *dest, vpn_packet_t *packet) {
+ struct ip ip;
+ vpn_packet_t fragment;
+ int len, maxlen, todo;
+ uint8_t *offset;
+ uint16_t ip_off, origf;
+
+ cp();
+
+ memcpy(&ip, packet->data + ether_size, ip_size);
+ fragment.priority = packet->priority;
+
+ if(ip.ip_hl != ip_size / 4)
+ return;
+
+ 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 (%d)"), 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);
+
+ offset = packet->data + ether_size + ip_size;
+ maxlen = (dest->mtu - ether_size - ip_size) & ~0x7;
+ ip_off = ntohs(ip.ip_off);
+ origf = ip_off & ~IP_OFFMASK;
+ ip_off &= IP_OFFMASK;
+
+ while(todo) {
+ len = todo > maxlen ? maxlen : todo;
+ memcpy(fragment.data + ether_size + ip_size, offset, len);
+ todo -= len;
+ offset += len;
+
+ ip.ip_len = htons(ip_size + len);
+ ip.ip_off = htons(ip_off | origf | (todo ? IP_MF : 0));
+ ip.ip_sum = 0;
+ ip.ip_sum = inet_checksum(&ip, ip_size, ~0);
+ memcpy(fragment.data, packet->data, ether_size);
+ memcpy(fragment.data + ether_size, &ip, ip_size);
+ fragment.len = ether_size + ip_size + len;
+
+ send_packet(dest, &fragment);
+
+ ip_off += len / 8;
+ }
+}
+
+static void route_ipv4_unicast(node_t *source, vpn_packet_t *packet)
{
subnet_t *subnet;
+ node_t *via;
cp();
if(!subnet->owner->status.reachable)
route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_NET_UNREACH);
- if(subnet->owner->options & OPTION_PMTU_DISCOVERY && packet->len > subnet->owner->mtu && subnet->owner != myself) {
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Packet for %s (%s) length %d larger than MTU %d"), subnet->owner->name, subnet->owner->hostname, packet->len, subnet->owner->mtu);
- packet->len = subnet->owner->mtu;
- route_ipv4_unreachable(source, packet, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED);
- return;
- }
-
if(priorityinheritance)
packet->priority = packet->data[15];
+ 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);
+ 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;
+ }
+
send_packet(subnet->owner, packet);
}
-static __inline__ void route_ipv4(node_t *source, vpn_packet_t *packet)
+static void route_ipv4(node_t *source, vpn_packet_t *packet)
{
cp();
send_packet(source, packet);
}
-static __inline__ 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;
cp();
if(!subnet->owner->status.reachable)
route_ipv6_unreachable(source, packet, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOROUTE);
+
+ via = (subnet->owner->via == myself) ? subnet->owner->nexthop : subnet->owner->via;
- if(subnet->owner->options & OPTION_PMTU_DISCOVERY && packet->len > subnet->owner->mtu && subnet->owner != myself) {
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Packet for %s (%s) length %d larger than MTU %d"), subnet->owner->name, subnet->owner->hostname, packet->len, subnet->owner->mtu);
- packet->len = subnet->owner->mtu;
+ 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);
+ packet->len = via->mtu;
route_ipv6_unreachable(source, packet, ICMP6_PACKET_TOO_BIG, 0);
return;
}
send_packet(source, packet);
}
-static __inline__ void route_ipv6(node_t *source, vpn_packet_t *packet)
+static void route_ipv6(node_t *source, vpn_packet_t *packet)
{
cp();