X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Froute.c;h=9ddb1d1c4c5c373b7a49ca591372cb9a718dd414;hp=77fb7d17e123454f66eca4245e8346a433d0a61b;hb=116ba3b3da73fb857cf75b5c92c6aacd70d94dd9;hpb=ab90fa9bd1a653a330be7ef11293000721a0e7b4 diff --git a/src/route.c b/src/route.c index 77fb7d17..9ddb1d1c 100644 --- a/src/route.c +++ b/src/route.c @@ -17,27 +17,32 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id: route.c,v 1.1.2.27 2002/03/01 14:25:10 guus Exp $ + $Id: route.c,v 1.1.2.40 2002/06/08 12:57:10 guus Exp $ */ #include "config.h" -#if defined(HAVE_FREEBSD) || defined(HAVE_OPENBSD) +#ifdef HAVE_SYS_PARAM_H #include #endif #include #include -#if defined(HAVE_SOLARIS) || defined(HAVE_OPENBSD) +#ifdef HAVE_NET_IF_H #include - #define ETHER_ADDR_LEN 6 -#else +#endif +#ifdef HAVE_NET_ETHERNET_H #include #endif +#include +#include #include #include #include #include #include +#ifdef HAVE_STDINT_H + #include +#endif #include @@ -50,6 +55,10 @@ #include "system.h" +#ifndef ETHER_ADDR_LEN + #define ETHER_ADDR_LEN 6 +#endif + int routing_mode = RMODE_ROUTER; int priorityinheritance = 0; int macexpire = 600; @@ -97,6 +106,7 @@ void age_mac(void) 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) { @@ -167,14 +177,14 @@ cp if(debug_lvl >= DEBUG_TRAFFIC) { syslog(LOG_WARNING, _("Cannot route packet: unknown IPv6 destination address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"), - ntohs(*(short unsigned int *)&packet->data[38]), - ntohs(*(short unsigned int *)&packet->data[40]), - ntohs(*(short unsigned int *)&packet->data[42]), - ntohs(*(short unsigned int *)&packet->data[44]), - ntohs(*(short unsigned int *)&packet->data[46]), - ntohs(*(short unsigned int *)&packet->data[48]), - ntohs(*(short unsigned int *)&packet->data[50]), - ntohs(*(short unsigned int *)&packet->data[52])); + ntohs(*(uint16_t *)&packet->data[38]), + ntohs(*(uint16_t *)&packet->data[40]), + ntohs(*(uint16_t *)&packet->data[42]), + ntohs(*(uint16_t *)&packet->data[44]), + ntohs(*(uint16_t *)&packet->data[46]), + ntohs(*(uint16_t *)&packet->data[48]), + ntohs(*(uint16_t *)&packet->data[50]), + ntohs(*(uint16_t *)&packet->data[52])); } return NULL; @@ -183,11 +193,136 @@ cp return subnet->owner; } +uint16_t inet_checksum(uint16_t *data, int len, uint16_t prevsum) +{ + uint32_t checksum = prevsum ^ 0xFFFF; + + while(len--) + checksum += ntohs(*data++); + + while(checksum >> 16) + checksum = (checksum & 0xFFFF) + (checksum >> 16); + + return checksum ^ 0xFFFF; +} + +void route_neighborsol(vpn_packet_t *packet) +{ + struct ip6_hdr *hdr; + struct nd_neighbor_solicit *ns; + struct nd_opt_hdr *opt; + subnet_t *subnet; + uint16_t checksum; + + struct { + struct in6_addr ip6_src; /* source address */ + struct in6_addr ip6_dst; /* destination address */ + uint32_t length; + uint8_t junk[4]; + } pseudo; + +cp + hdr = (struct ip6_hdr *)(packet->data + 14); + ns = (struct nd_neighbor_solicit *)(packet->data + 14 + sizeof(*hdr)); + opt = (struct nd_opt_hdr *)(packet->data + 14 + sizeof(*hdr) + sizeof(*ns)); + + /* First, snatch the source address from the neighbor solicitation packet */ + + memcpy(mymac.net.mac.address.x, packet->data + 6, 6); + + /* 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) + { + if(debug_lvl > DEBUG_TRAFFIC) + { + syslog(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.junk[0] = pseudo.junk[1] = pseudo.junk[2] = 0; + pseudo.junk[3] = IPPROTO_ICMPV6; + + /* Generate checksum */ + + checksum = inet_checksum((uint16_t *)&pseudo, sizeof(pseudo)/2, ~0); + checksum = inet_checksum((uint16_t *)ns, sizeof(*ns)/2 + 4, checksum); + + if(checksum) + { + if(debug_lvl >= DEBUG_TRAFFIC) + syslog(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) + { + if(debug_lvl >= DEBUG_TRAFFIC) + { + syslog(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.junk[0] = pseudo.junk[1] = pseudo.junk[2] = 0; + pseudo.junk[3] = IPPROTO_ICMPV6; + + /* Generate checksum */ + + checksum = inet_checksum((uint16_t *)&pseudo, sizeof(pseudo)/2, ~0); + checksum = inet_checksum((uint16_t *)ns, sizeof(*ns)/2 + 4, checksum); + + ns->nd_ns_hdr.icmp6_cksum = htons(checksum); + + write_packet(packet); +cp +} + void route_arp(vpn_packet_t *packet) { struct ether_arp *arp; subnet_t *subnet; - unsigned char ipbuf[4]; + uint8_t ipbuf[4]; cp /* First, snatch the source address from the ARP packet */ @@ -204,8 +339,8 @@ cp if(ntohs(arp->arp_hrd) != ARPHRD_ETHER || ntohs(arp->arp_pro) != ETHERTYPE_IP || - (int) (arp->arp_hln) != ETHER_ADDR_LEN || - (int) (arp->arp_pln) != 4 || + arp->arp_hln != ETHER_ADDR_LEN || + arp->arp_pln != 4 || ntohs(arp->arp_op) != ARPOP_REQUEST ) { if(debug_lvl > DEBUG_TRAFFIC) @@ -215,7 +350,7 @@ cp return; } - /* Check if the IP address exists on the VPN */ + /* Check if the IPv4 address exists on the VPN */ subnet = lookup_subnet_ipv4((ipv4_t *)arp->arp_tpa); @@ -252,21 +387,26 @@ cp void route_outgoing(vpn_packet_t *packet) { - unsigned short int type; - node_t *n; + uint16_t type; + node_t *n = NULL; cp /* FIXME: multicast? */ switch(routing_mode) { case RMODE_ROUTER: - type = ntohs(*((unsigned short*)(&packet->data[12]))); + type = ntohs(*((uint16_t *)(&packet->data[12]))); switch(type) { case 0x0800: n = route_ipv4(packet); break; case 0x86DD: + if(packet->data[20] == IPPROTO_ICMPV6 && packet->data[54] == ND_NEIGHBOR_SOLICIT) + { + route_neighborsol(packet); + return; + } n = route_ipv6(packet); break; case 0x0806: @@ -303,9 +443,22 @@ void route_incoming(node_t *source, vpn_packet_t *packet) { case RMODE_ROUTER: { - node_t *n; + node_t *n = NULL; + uint16_t type; - n = route_ipv4(packet); + type = ntohs(*((uint16_t *)(&packet->data[12]))); + switch(type) + { + case 0x0800: + n = route_ipv4(packet); + break; + case 0x86DD: + n = route_ipv6(packet); + break; + default: + n = myself; + break; + } if(n) {