X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fpokey%2Froute.c;fp=src%2Fpokey%2Froute.c;h=cd5946ce01d0634489f63cb1309bfabf3d1380dc;hb=04d33be4bd102de67bb6dba5c449e12fea0db4d2;hp=0000000000000000000000000000000000000000;hpb=b0a676988a8da3120e64ef0e1a4ea4c28b1511e1;p=tinc diff --git a/src/pokey/route.c b/src/pokey/route.c new file mode 100644 index 00000000..cd5946ce --- /dev/null +++ b/src/pokey/route.c @@ -0,0 +1,377 @@ +/* + route.c -- routing + 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 + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + 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 2002/04/28 12:46:26 zarq Exp $ +*/ + +#include "config.h" + +#if defined(HAVE_FREEBSD) || defined(HAVE_OPENBSD) + #include +#endif +#include +#include +#if defined(HAVE_SOLARIS) || defined(HAVE_OPENBSD) + #include + #define ETHER_ADDR_LEN 6 +#else + #include +#endif +#include +#include +#include +#include +#include +#include + +#include + +#include "net.h" +#include "interface.h" +#include "connection.h" +#include "subnet.h" +#include "route.h" +#include "protocol.h" +#include "device.h" +#include "logging.h" + +#include "system.h" + +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 *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; +} + +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 + /* 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; +} + +node_t *route_ipv4(vpn_packet_t *packet) +{ + subnet_t *subnet; +cp + 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 IPv4 destination address %d.%d.%d.%d"), + packet->data[30], packet->data[31], packet->data[32], packet->data[33]); + } + + return NULL; + } +cp + return subnet->owner; +} + +node_t *route_ipv6(vpn_packet_t *packet) +{ + subnet_t *subnet; +cp + subnet = lookup_subnet_ipv6((ipv6_t *)&packet->data[38]); +cp + 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(*(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])); + } + + return NULL; + } +cp + return subnet->owner; +} + +unsigned short int inet_checksum(unsigned short int *data, int len, unsigned short int prevsum) +{ + unsigned long int 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; + short unsigned int 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((unsigned short int *)&pseudo, sizeof(pseudo)/2, ~0); + checksum = inet_checksum((unsigned short int *)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((unsigned short int *)&pseudo, sizeof(pseudo)/2, ~0); + checksum = inet_checksum((unsigned short int *)ns, sizeof(*ns)/2 + 4, checksum); + + ns->nd_ns_hdr.icmp6_cksum = htons(checksum); +cp +} + +void route_arp(vpn_packet_t *packet) +{ + struct ether_arp *arp; + subnet_t *subnet; + unsigned char 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 || + (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 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); +cp +} +