X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Froute.c;h=9ddb1d1c4c5c373b7a49ca591372cb9a718dd414;hp=dc91940ac8d3c47ec1188d6deb431cc9d9774207;hb=116ba3b3da73fb857cf75b5c92c6aacd70d94dd9;hpb=fcbe215d64d7e2f3b159fff6422d750417877ac4 diff --git a/src/route.c b/src/route.c index dc91940a..9ddb1d1c 100644 --- a/src/route.c +++ b/src/route.c @@ -1,7 +1,7 @@ /* route.c -- routing - Copyright (C) 2000,2001 Ivo Timmermans , - 2000,2001 Guus Sliepen + Copyright (C) 2000-2002 Ivo Timmermans , + 2000-2002 Guus Sliepen 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 @@ -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 1.1.2.18 2001/07/21 20:21:25 guus Exp $ + $Id: route.c,v 1.1.2.40 2002/06/08 12:57:10 guus Exp $ */ #include "config.h" -#ifdef HAVE_FREEBSD +#ifdef HAVE_SYS_PARAM_H #include #endif #include #include -#ifdef HAVE_SOLARIS +#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 @@ -46,17 +51,24 @@ #include "subnet.h" #include "route.h" #include "protocol.h" +#include "device.h" #include "system.h" +#ifndef ETHER_ADDR_LEN + #define ETHER_ADDR_LEN 6 +#endif + int routing_mode = RMODE_ROUTER; +int priorityinheritance = 0; +int macexpire = 600; subnet_t mymac; void learn_mac(mac_t *address) { subnet_t *subnet; avl_node_t *node; - connection_t *p; + connection_t *c; cp subnet = lookup_subnet_mac(address); @@ -65,7 +77,7 @@ cp if(!subnet || subnet->owner!=myself) { if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_INFO, _("Learned new MAC address %hhx:%hhx:%hhx:%hhx:%hhx:%hhx"), + syslog(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(); @@ -77,14 +89,43 @@ cp for(node = connection_tree->head; node; node = node->next) { - p = (connection_t *)node->data; - if(p->status.active) - send_add_subnet(p, subnet); + c = (connection_t *)node->data; + if(c->status.active) + send_add_subnet(c, subnet); } } + + subnet->net.mac.lastseen = now; } -connection_t *route_mac(vpn_packet_t *packet) +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) + { + if(debug_lvl >= DEBUG_TRAFFIC) + syslog(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); + } + } +cp +} + +node_t *route_mac(vpn_packet_t *packet) { subnet_t *subnet; cp @@ -102,25 +143,20 @@ cp return NULL; } -connection_t *route_ipv4(vpn_packet_t *packet) +node_t *route_ipv4(vpn_packet_t *packet) { - ipv4_t dest; subnet_t *subnet; cp -#ifdef HAVE_SOLARIS - /* The other form gives bus errors on a SparcStation 20. */ - dest = ((packet->data[30] * 0x100 + packet->data[31]) * 0x100 + packet->data[32]) * 0x100 + packet->data[33]; -#else - dest = ntohl(*((unsigned long*)(&packet->data[30]))); -#endif -cp - subnet = lookup_subnet_ipv4(&dest); + if(priorityinheritance) + packet->priority = packet->data[15]; + + subnet = lookup_subnet_ipv4((ipv4_t *)&packet->data[30]); cp if(!subnet) { if(debug_lvl >= DEBUG_TRAFFIC) { - syslog(LOG_WARNING, _("Cannot route packet: unknown destination address %d.%d.%d.%d"), + syslog(LOG_WARNING, _("Cannot route packet: unknown IPv4 destination address %d.%d.%d.%d"), packet->data[30], packet->data[31], packet->data[32], packet->data[33]); } @@ -130,23 +166,163 @@ cp return subnet->owner; } -connection_t *route_ipv6(vpn_packet_t *packet) +node_t *route_ipv6(vpn_packet_t *packet) { + subnet_t *subnet; +cp + subnet = lookup_subnet_ipv6((ipv6_t *)&packet->data[38]); cp - if(debug_lvl > DEBUG_NOTHING) + if(!subnet) { - syslog(LOG_WARNING, _("Cannot route packet: IPv6 routing not yet implemented")); - } + if(debug_lvl >= DEBUG_TRAFFIC) + { + syslog(LOG_WARNING, _("Cannot route packet: unknown IPv6 destination address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"), + 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; + } +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 - return NULL; } void route_arp(vpn_packet_t *packet) { struct ether_arp *arp; subnet_t *subnet; - unsigned char ipbuf[4]; - ipv4_t dest; + uint8_t ipbuf[4]; cp /* First, snatch the source address from the ARP packet */ @@ -163,8 +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) @@ -174,10 +350,9 @@ cp return; } - /* Check if the IP address exists on the VPN */ + /* Check if the IPv4 address exists on the VPN */ - dest = ntohl(*((unsigned long*)(arp->arp_tpa))); - subnet = lookup_subnet_ipv4(&dest); + subnet = lookup_subnet_ipv4((ipv4_t *)arp->arp_tpa); if(!subnet) { @@ -206,28 +381,33 @@ cp memcpy(arp->arp_sha, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* add fake source hard addr */ arp->arp_op = htons(ARPOP_REPLY); - accept_packet(packet); + write_packet(packet); cp } void route_outgoing(vpn_packet_t *packet) { - unsigned short int type; - connection_t *cl; + 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: - cl = route_ipv4(packet); + n = route_ipv4(packet); break; case 0x86DD: - cl = route_ipv6(packet); + if(packet->data[20] == IPPROTO_ICMPV6 && packet->data[54] == ND_NEIGHBOR_SOLICIT) + { + route_neighborsol(packet); + return; + } + n = route_ipv6(packet); break; case 0x0806: route_arp(packet); @@ -239,14 +419,14 @@ cp } return; } - if(cl) - send_packet(cl, packet); + if(n) + send_packet(n, packet); break; case RMODE_SWITCH: - cl = route_mac(packet); - if(cl) - send_packet(cl, packet); + n = route_mac(packet); + if(n) + send_packet(n, packet); else broadcast_packet(myself, packet); break; @@ -257,13 +437,40 @@ cp } } -void route_incoming(connection_t *source, vpn_packet_t *packet) +void route_incoming(node_t *source, vpn_packet_t *packet) { switch(routing_mode) { case RMODE_ROUTER: - memcpy(packet->data, mymac.net.mac.address.x, 6); /* Override destination address to make the kernel accept it */ - accept_packet(packet); + { + node_t *n = NULL; + uint16_t type; + + 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) + { + if(n == myself) + { + memcpy(packet->data, mymac.net.mac.address.x, 6); + write_packet(packet); + } + else + send_packet(n, packet); + } + } break; case RMODE_SWITCH: { @@ -274,20 +481,20 @@ void route_incoming(connection_t *source, vpn_packet_t *packet) if(subnet) { if(subnet->owner == myself) - accept_packet(packet); + write_packet(packet); else send_packet(subnet->owner, packet); } else { broadcast_packet(source, packet); - accept_packet(packet); + write_packet(packet); } } break; case RMODE_HUB: - broadcast_packet(source,packet); /* Spread it on */ - accept_packet(packet); + broadcast_packet(source, packet); /* Spread it on */ + write_packet(packet); break; } }