-/* Missing definitions */
-
-#ifndef ETHER_ADDR_LEN
-#define ETHER_ADDR_LEN 6
-#endif
-
-#ifndef ICMP_DEST_UNREACH
-#define ICMP_DEST_UNREACH 3
-#endif
-
-#ifndef ICMP_NET_UNKNOWN
-#define ICMP_NET_UNKNOWN 6
-#endif
-
-#ifndef ICMP_NET_UNREACH
-#define ICMP_NET_UNREACH 0
-#endif
-
-int routing_mode = RMODE_ROUTER;
-int priorityinheritance = 0;
-int macexpire = 600;
-int overwrite_mac = 0;
-mac_t mymac = {{0xFE, 0xFD, 0, 0, 0, 0}};
-
-/* RFC 1071 */
-
-static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
-{
- uint16_t *p = data;
- uint32_t checksum = prevsum ^ 0xFFFF;
-
- while(len >= 2) {
- checksum += *p++;
- len -= 2;
- }
-
- if(len)
- checksum += *(unsigned char *)p;
-
- while(checksum >> 16)
- checksum = (checksum & 0xFFFF) + (checksum >> 16);
-
- return ~checksum;
-}
-
-static int ratelimit(void) {
- static time_t lasttime = 0;
-
- if(lasttime == now)
- return 1;
-
- lasttime = now;
- return 0;
-}
-
-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 || subnet->owner != myself) {
- 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 = new_subnet();
- subnet->type = SUBNET_MAC;
- memcpy(&subnet->net.mac.address, address, sizeof(mac_t));
- subnet_add(myself, subnet);
-
- /* And tell all other tinc daemons it's our MAC */
-
- for(node = connection_tree->head; node; node = node->next) {
- c = (connection_t *) node->data;
- if(c->status.active)
- send_add_subnet(c, subnet);
- }
- }
-
- subnet->net.mac.lastseen = now;
-}
-
-void age_mac(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 = (subnet_t *) node->data;
- if(s->type == SUBNET_MAC && s->net.mac.lastseen && s->net.mac.lastseen + macexpire < now) {
- ifdebug(TRAFFIC) logger(LOG_INFO, _("MAC address %hx:%hx:%hx:%hx:%hx:%hx expired"),
- s->net.mac.address.x[0], s->net.mac.address.x[1],
- s->net.mac.address.x[2], s->net.mac.address.x[3],
- s->net.mac.address.x[4], s->net.mac.address.x[5]);
-
- for(node2 = connection_tree->head; node2; node2 = node2->next) {
- c = (connection_t *) node2->data;
- if(c->status.active)
- send_del_subnet(c, s);
- }
-
- subnet_del(myself, s);
- }
- }
-}
-
-static node_t *route_mac(vpn_packet_t *packet)
-{
- subnet_t *subnet;
-
- cp();
-
- /* Learn source address */
-
- learn_mac((mac_t *)(&packet->data[6]));
-
- /* Lookup destination address */
-
- subnet = lookup_subnet_mac((mac_t *)(&packet->data[0]));
-
- if(subnet)
- return subnet->owner;
- else
- return NULL;
-}
-
-/* RFC 792 */
-
-static void route_ipv4_unreachable(vpn_packet_t *packet, uint8_t code)
-{
- struct ip *hdr;
- struct icmp *icmp;
-
- struct in_addr ip_src;
- struct in_addr ip_dst;
- uint32_t oldlen;
-
- if(ratelimit())
- return;
-
- cp();
-
- hdr = (struct ip *)(packet->data + 14);
- icmp = (struct icmp *)(packet->data + 14 + 20);
-
- /* Remember original source and destination */
-
- memcpy(&ip_src, &hdr->ip_src, 4);
- memcpy(&ip_dst, &hdr->ip_dst, 4);
- oldlen = packet->len - 14;
-
- if(oldlen >= IP_MSS - sizeof(*hdr) - sizeof(*icmp))
- oldlen = IP_MSS - sizeof(*hdr) - sizeof(*icmp);
-
- /* Copy first part of original contents to ICMP message */
-
- memmove(&icmp->icmp_ip, hdr, oldlen);
-
- /* Fill in IPv4 header */
-
- hdr->ip_v = 4;
- hdr->ip_hl = sizeof(*hdr) / 4;
- hdr->ip_tos = 0;
- hdr->ip_len = htons(20 + 8 + oldlen);
- hdr->ip_id = 0;
- hdr->ip_off = 0;
- hdr->ip_ttl = 255;
- hdr->ip_p = IPPROTO_ICMP;
- hdr->ip_sum = 0;
- memcpy(&hdr->ip_src, &ip_dst, 4);
- memcpy(&hdr->ip_dst, &ip_src, 4);
-
- hdr->ip_sum = inet_checksum(hdr, 20, ~0);
-
- /* Fill in ICMP header */
-
- icmp->icmp_type = ICMP_DEST_UNREACH;
- icmp->icmp_code = code;
- icmp->icmp_cksum = 0;
-
- icmp->icmp_cksum = inet_checksum(icmp, 8 + oldlen, ~0);
-
- packet->len = 14 + 20 + 8 + oldlen;
-
- write_packet(packet);
-}