X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Froute.c;h=ff84ee985864ea5a25c88448d7cc788d947c49b2;hp=cb74832cbec503843fc34e8a9c7c6f5049d780ab;hb=3e3b4a3190cf950c265a8c62d577812a22b11dcc;hpb=fa376fbd4e5151ae43e86441a1e99073eeaf46a5 diff --git a/src/route.c b/src/route.c index cb74832c..ff84ee98 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 @@ -17,247 +17,487 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id: route.c,v 1.1.2.12 2001/06/05 16:31:59 guus Exp $ + $Id: route.c,v 1.1.2.46 2002/09/09 22:33:16 guus Exp $ */ #include "config.h" -#ifdef HAVE_FREEBSD - #include +#ifdef HAVE_SYS_PARAM_H +#include #endif #include #include +#ifdef HAVE_NET_IF_H +#include +#endif +#ifdef HAVE_NET_ETHERNET_H #include +#endif +#ifdef HAVE_NETINET_IN_SYSTM_H +#include +#endif +#include +#include #include #include #include #include +#include +#ifdef HAVE_INTTYPES_H +#include +#endif + +#include #include "net.h" -#include "net/ethernet.h" -#include "netinet/if_ether.h" #include "connection.h" #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(connection_t *source, mac_t *address) +void learn_mac(mac_t *address) { - subnet_t *subnet; -cp - subnet = lookup_subnet_mac(address); - - if(!subnet) - { - subnet = new_subnet(); - subnet->type = SUBNET_MAC; -// subnet->lasttime = gettimeofday(); - memcpy(&subnet->net.mac.address, address, sizeof(mac_t)); - subnet_add(source, subnet); - - if(debug_lvl >= DEBUG_TRAFFIC) - { - syslog(LOG_DEBUG, _("Learned new MAC address %x:%x:%x:%x:%x:%x from %s (%s)"), - address->x[0], - address->x[1], - address->x[2], - address->x[3], - address->x[4], - address->x[5], - source->name, source->hostname); - } - } + 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) { + if(debug_lvl >= DEBUG_TRAFFIC) + 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(); + 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; } -connection_t *route_mac(connection_t *source, vpn_packet_t *packet) +void age_mac(void) { - subnet_t *subnet; -cp - /* Learn source address */ - - learn_mac(source, (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; + 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); + } + } } -connection_t *route_ipv4(vpn_packet_t *packet) +node_t *route_mac(vpn_packet_t *packet) { - ipv4_t dest; - subnet_t *subnet; -cp - dest = ntohl(*((unsigned long*)(&packet->data[30]))); - - subnet = lookup_subnet_ipv4(&dest); - - if(!subnet) - { - if(debug_lvl >= DEBUG_TRAFFIC) - { - syslog(LOG_WARNING, _("Cannot route packet: unknown destination address %d.%d.%d.%d"), - packet->data[30], packet->data[31], packet->data[32], packet->data[33]); - } - - return NULL; - } -cp - return subnet->owner; + 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; } -connection_t *route_ipv6(vpn_packet_t *packet) +node_t *route_ipv4(vpn_packet_t *packet) { -cp - if(debug_lvl > DEBUG_NOTHING) - { - syslog(LOG_WARNING, _("Cannot route packet: IPv6 routing not yet implemented")); - } -cp - return NULL; + subnet_t *subnet; + + cp(); + + if(priorityinheritance) + packet->priority = packet->data[15]; + + subnet = lookup_subnet_ipv4((ipv4_t *) & packet->data[30]); + + if(!subnet) { + if(debug_lvl >= DEBUG_TRAFFIC) { + 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]); + } + + return NULL; + } + + return subnet->owner; +} + +node_t *route_ipv6(vpn_packet_t *packet) +{ + subnet_t *subnet; + + cp(); + + subnet = lookup_subnet_ipv6((ipv6_t *) & packet->data[38]); + + if(!subnet) { + 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; + } + + 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); } void route_arp(vpn_packet_t *packet) { - struct ether_arp *arp; - subnet_t *subnet; - unsigned char ipbuf[4]; - ipv4_t dest; -cp - /* First, snatch the source address from the ARP packet */ - - memcpy(mymac.net.mac.address.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) - */ - - arp = (struct ether_arp *)(packet->data + 14); - - /* Check if this is a valid ARP request */ - - 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 || - ntohs(arp->arp_op) != ARPOP_REQUEST ) - { - if(debug_lvl > DEBUG_TRAFFIC) - { - syslog(LOG_WARNING, _("Cannot route packet: received unknown type ARP request")); - } - return; - } - - /* Check if the IP address exists on the VPN */ - - dest = ntohl(*((unsigned long*)(arp->arp_tpa))); - subnet = lookup_subnet_ipv4(&dest); - - if(!subnet) - { - if(debug_lvl >= DEBUG_TRAFFIC) - { - syslog(LOG_WARNING, _("Cannot route packet: ARP request for unknown address %d.%d.%d.%d"), - arp->arp_tpa[0], arp->arp_tpa[1], arp->arp_tpa[2], arp->arp_tpa[3]); - } - - return; - } - - /* Check if it is for our own subnet */ - - if(subnet->owner == myself) - return; /* silently ignore */ - - 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(ipbuf, arp->arp_tpa, 4); /* save protocol addr */ - memcpy(arp->arp_tpa, arp->arp_spa, 4); /* swap destination and source protocol address */ - memcpy(arp->arp_spa, ipbuf, 4); /* ... */ - - memcpy(arp->arp_tha, arp->arp_sha, 10); /* set target hard/proto addr */ - 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); -cp + struct ether_arp *arp; + subnet_t *subnet; + uint8_t ipbuf[4]; + + cp(); + + /* First, snatch the source address from the ARP packet */ + + memcpy(mymac.net.mac.address.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) + */ + + arp = (struct ether_arp *)(packet->data + 14); + + /* Check if this is a valid ARP request */ + + if(ntohs(arp->arp_hrd) != ARPHRD_ETHER || ntohs(arp->arp_pro) != ETHERTYPE_IP || + arp->arp_hln != ETHER_ADDR_LEN || arp->arp_pln != 4 || ntohs(arp->arp_op) != ARPOP_REQUEST) { + if(debug_lvl > DEBUG_TRAFFIC) { + syslog(LOG_WARNING, _("Cannot route packet: received unknown type ARP request")); + } + return; + } + + /* Check if the IPv4 address exists on the VPN */ + + subnet = lookup_subnet_ipv4((ipv4_t *) arp->arp_tpa); + + if(!subnet) { + if(debug_lvl >= DEBUG_TRAFFIC) { + syslog(LOG_WARNING, _("Cannot route packet: ARP request for unknown address %d.%d.%d.%d"), + arp->arp_tpa[0], arp->arp_tpa[1], arp->arp_tpa[2], + arp->arp_tpa[3]); + } + + return; + } + + /* Check if it is for our own subnet */ + + if(subnet->owner == myself) + return; /* silently ignore */ + + 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(ipbuf, arp->arp_tpa, 4); /* save protocol addr */ + memcpy(arp->arp_tpa, arp->arp_spa, 4); /* swap destination and source protocol address */ + memcpy(arp->arp_spa, ipbuf, 4); /* ... */ + + memcpy(arp->arp_tha, arp->arp_sha, 10); /* set target hard/proto addr */ + memcpy(arp->arp_sha, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* add fake source hard addr */ + arp->arp_op = htons(ARPOP_REPLY); + + write_packet(packet); } void route_outgoing(vpn_packet_t *packet) { - unsigned short int type; - connection_t *cl; -cp - /* FIXME: multicast? */ - - switch(routing_mode) - { - case RMODE_ROUTER: - type = ntohs(*((unsigned short*)(&packet->data[12]))); - switch(type) - { - case 0x0800: - cl = route_ipv4(packet); - break; - case 0x86DD: - cl = route_ipv6(packet); - break; - case 0x0806: - route_arp(packet); - return; - default: - if(debug_lvl >= DEBUG_TRAFFIC) - { - syslog(LOG_WARNING, _("Cannot route packet: unknown type %hx"), type); - } - return; - } - if(cl) - send_packet(cl, packet); - break; - - case RMODE_SWITCH: - cl = route_mac(myself, packet); - if(cl) - send_packet(cl, packet); - else - broadcast_packet(myself, packet); - break; - - case RMODE_HUB: - broadcast_packet(myself, packet); - break; - } + uint16_t type; + node_t *n = NULL; + + cp(); + + /* FIXME: multicast? */ + + switch (routing_mode) { + case RMODE_ROUTER: + 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: + route_arp(packet); + return; + + default: + if(debug_lvl >= DEBUG_TRAFFIC) + syslog(LOG_WARNING, _("Cannot route packet: unknown type %hx"), type); + return; + } + if(n) + send_packet(n, packet); + break; + + case RMODE_SWITCH: + n = route_mac(packet); + if(n) + send_packet(n, packet); + else + broadcast_packet(myself, packet); + break; + + case RMODE_HUB: + broadcast_packet(myself, packet); + break; + } } -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 */ - break; - case RMODE_SWITCH: - if((packet->data[0] & packet->data[1]) == 0xFF) /* Broadcast? */ - broadcast_packet(source, packet); /* If yes, spread it on */ - else - learn_mac(source, (mac_t *)(&packet->data[6])); - break; - case RMODE_HUB: - broadcast_packet(source,packet); /* Spread it on */ - break; - } - - accept_packet(packet); + switch (routing_mode) { + case RMODE_ROUTER: + { + 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: + { + subnet_t *subnet; + + subnet = lookup_subnet_mac((mac_t *)(&packet->data[0])); + + if(subnet) { + if(subnet->owner == myself) + write_packet(packet); + else + send_packet(subnet->owner, packet); + } else { + broadcast_packet(source, packet); + write_packet(packet); + } + } + break; + + case RMODE_HUB: + broadcast_packet(source, packet); /* Spread it on */ + write_packet(packet); + break; + } }