- /* 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) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: received unknown type neighbor solicitation request"));
- return;
- }
-
- /* Create pseudo header */
-
- memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
- memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
- pseudo.length = htonl(sizeof(*ns) + sizeof(*opt) + 6);
- pseudo.next = htonl(IPPROTO_ICMPV6);
-
- /* Generate checksum */
-
- checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
- checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
-
- if(checksum) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: checksum error for neighbor solicitation request"));
- return;
- }
-
- /* Check if the IPv6 address exists on the VPN */
-
- 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"),
- ntohs(((uint16_t *) &ns->nd_ns_target)[0]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[1]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[2]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[3]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[4]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[5]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[6]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[7]));
-
- return;
- }
-
- /* Check if it is for our own subnet */
-
- if(subnet->owner == myself)
- return; /* silently ignore */
-
- /* Create neighbor advertation reply */
-
- memcpy(packet->data, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* copy destination address */
- packet->data[ETHER_ADDR_LEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
-
- memcpy(&hdr->ip6_dst, &hdr->ip6_src, 16); /* swap destination and source protocol address */
- memcpy(&hdr->ip6_src, &ns->nd_ns_target, 16); /* ... */
-
- memcpy((char *) opt + sizeof(*opt), packet->data + ETHER_ADDR_LEN, 6); /* add fake source hard addr */
-
- ns->nd_ns_hdr.icmp6_cksum = 0;
- ns->nd_ns_hdr.icmp6_type = ND_NEIGHBOR_ADVERT;
- ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[0] = 0x40; /* Set solicited flag */
- ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[1] =
- ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[2] =
- ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[3] = 0;
- opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
-
- /* Create pseudo header */
-
- memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
- memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
- pseudo.length = htonl(sizeof(*ns) + sizeof(*opt) + 6);
- pseudo.next = htonl(IPPROTO_ICMPV6);
-
- /* Generate checksum */
-
- checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
- checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
-
- ns->nd_ns_hdr.icmp6_cksum = checksum;
-
- write_packet(packet);
-}
-
-/* RFC 826 */
-
-static void route_arp(vpn_packet_t *packet)
-{
- struct ether_arp *arp;
- subnet_t *subnet;
- uint8_t ipbuf[4];
-
- cp();
-
- /* First, snatch the source address from the ARP packet */
-
- if(overwrite_mac)
- memcpy(mymac.x, packet->data + 6, 6);
-
- /* This routine generates replies to ARP requests.
- You don't need to set NOARP flag on the interface anymore (which is broken on FreeBSD).
- Most of the code here is taken from choparp.c by Takamichi Tateoka (tree@mma.club.uec.ac.jp)
- */