/*
route.c -- routing
- Copyright (C) 2000-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
- 2000-2002 Guus Sliepen <guus@sliepen.warande.net>
+ Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
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
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 1.1.2.32 2002/03/12 14:25:04 guus Exp $
+ 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.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#include "config.h"
-
-#if defined(HAVE_FREEBSD) || defined(HAVE_OPENBSD)
- #include <sys/param.h>
-#endif
-#include <sys/socket.h>
-#include <netinet/in.h>
-#if defined(HAVE_SOLARIS) || defined(HAVE_OPENBSD)
- #include <net/if.h>
- #define ETHER_ADDR_LEN 6
-#else
- #include <net/ethernet.h>
-#endif
-#ifdef NEIGHBORSOL
-#include <netinet/ip6.h>
-#include <netinet/icmp6.h>
-#endif
-#include <netinet/if_ether.h>
-#include <utils.h>
-#include <xalloc.h>
-#include <syslog.h>
-#include <string.h>
-
-#include <avl_tree.h>
+#include "system.h"
+#include "logger.h"
+#include "meshlink_internal.h"
#include "net.h"
-#include "connection.h"
-#include "subnet.h"
#include "route.h"
-#include "protocol.h"
-#include "device.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);
+#include "utils.h"
- /* 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);
+static bool checklength(node_t *source, vpn_packet_t *packet, uint16_t length) {
+ assert(length);
- /* 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);
+ if(packet->len < length) {
+ logger(source->mesh, MESHLINK_WARNING, "Got too short packet from %s", source->name);
+ return false;
+ } else {
+ return true;
}
- }
-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;
-}
-
-#ifdef NEIGHBORSOL
-unsigned short int ipv6_cksum(short int *data, int len, unsigned short int cksum)
-{
- while(len--)
- {
- cksum += ntohs(*data++);
- }
- return cksum;
-}
-
-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 int cksum;
-
- 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(struct ip6_hdr));
- opt = (struct nd_opt_hdr *)(packet->data + 14 + sizeof(struct ip6_hdr) + sizeof(struct nd_neighbor_solicit));
-
- /* 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;
- }
-
- /* Check if the IPv6 address exists on the VPN */
-#if 0
- 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(ns->nd_ns_target.s6_addr16[0]), ntohs(ns->nd_ns_target.s6_addr16[1]), ntohs(ns->nd_ns_target.s6_addr16[2]), ntohs(ns->nd_ns_target.s6_addr16[3]),
- ntohs(ns->nd_ns_target.s6_addr16[4]), ntohs(ns->nd_ns_target.s6_addr16[5]), ntohs(ns->nd_ns_target.s6_addr16[6]), ntohs(ns->nd_ns_target.s6_addr16[7]));
- }
-
- return;
- }
+void route(meshlink_handle_t *mesh, node_t *source, vpn_packet_t *packet) {
+ assert(source);
- /* Check if it is for our own subnet */
-
- if(subnet->owner == myself)
- return; /* silently ignore */
-#endif
-
- syslog(LOG_DEBUG, "Neighbor solicitation request with checksum %hx", ntohs(ns->nd_ns_hdr.icmp6_cksum));
-
- /* Create pseudo header */
+ // TODO: route on name or key
- memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
- memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
- pseudo.length = htonl(sizeof(*ns));
- pseudo.junk[0] = pseudo.junk[1] = pseudo.junk[2] = 0;
- pseudo.junk[3] = IPPROTO_ICMPV6;
-
- /* Generate checksum */
-
- ns->nd_ns_hdr.icmp6_cksum = 0;
-
- cksum = ipv6_cksum((short int *)&pseudo, sizeof(pseudo)/2, 0);
+ meshlink_packethdr_t *hdr = (meshlink_packethdr_t *) packet->data;
+ node_t *dest = lookup_node(mesh, (char *)hdr->destination);
+ logger(mesh, MESHLINK_DEBUG, "Routing packet from \"%s\" to \"%s\"\n", hdr->source, hdr->destination);
- syslog(LOG_DEBUG, "Our checksum %hx", cksum);
-
- cksum = ipv6_cksum((short int *)ns, sizeof(*ns)/2, cksum);
-
- syslog(LOG_DEBUG, "Our checksum %hx", cksum);
-
- cksum = ipv6_cksum((short int *)opt, sizeof(*opt)/2, cksum);
-
- syslog(LOG_DEBUG, "Our checksum %hx", cksum);
-
- /* 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;
- 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(struct icmp6_hdr));
- pseudo.junk[0] = pseudo.junk[1] = pseudo.junk[2] = 0;
- pseudo.junk[3] = IPPROTO_ICMPV6;
-
- /* Generate checksum */
-
- cksum = ipv6_cksum((short int *)&pseudo, sizeof(pseudo)/2, 0);
- cksum = ipv6_cksum((short int *)ns, sizeof(*ns)/2, cksum);
-
- ns->nd_ns_hdr.icmp6_cksum = htons(cksum);
-
- write_packet(packet);
-cp
-}
-#endif
-
-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 Length
+ if(!checklength(source, packet, sizeof(*hdr))) {
+ return;
+ }
- /* Check if it is for our own subnet */
-
- if(subnet->owner == myself)
- return; /* silently ignore */
+ if(dest == NULL) {
+ //Lookup failed
+ logger(mesh, MESHLINK_WARNING, "Can't lookup the destination of a packet in the route() function. This should never happen!\n");
+ logger(mesh, MESHLINK_WARNING, "Destination was: %s\n", hdr->destination);
+ return;
+ }
- 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 */
+ if(dest == mesh->self) {
+ const void *payload = packet->data + sizeof(*hdr);
+ size_t len = packet->len - sizeof(*hdr);
- 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); /* ... */
+ char hex[len * 2 + 1];
- 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);
-cp
-}
+ if(mesh->log_level <= MESHLINK_DEBUG) {
+ bin2hex(payload, hex, len); // don't do this unless it's going to be logged
+ }
-void route_outgoing(vpn_packet_t *packet)
-{
- unsigned short int type;
- node_t *n = NULL;
-cp
- /* FIXME: multicast? */
+ logger(mesh, MESHLINK_DEBUG, "I received a packet for me with payload: %s\n", hex);
- switch(routing_mode)
- {
- case RMODE_ROUTER:
- type = ntohs(*((unsigned short*)(&packet->data[12])));
- switch(type)
- {
- case 0x0800:
- n = route_ipv4(packet);
- break;
- case 0x86DD:
- n = route_ipv6(packet);
-#ifdef NEIGHBORSOL
- if(!n && packet->data[0] == 0x33 && packet->data[1] == 0x33 && packet->data[2] == 0xff)
- {
- route_neighborsol(packet);
- return;
+ if(mesh->receive_cb) {
+ mesh->receive_cb(mesh, (meshlink_node_t *)source, payload, len);
}
-#endif
- 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(node_t *source, vpn_packet_t *packet)
-{
- switch(routing_mode)
- {
- case RMODE_ROUTER:
- {
- node_t *n = NULL;
- unsigned short int type;
-
- type = ntohs(*((unsigned short*)(&packet->data[12])));
- switch(type)
- {
- case 0x0800:
- n = route_ipv4(packet);
- break;
- case 0x86DD:
- n = route_ipv6(packet);
- break;
- default:
- n = myself;
- break;
- }
+ return;
+ }
- 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;
+ if(!dest->status.reachable) {
+ //TODO: check what to do here, not just print a warning
+ logger(mesh, MESHLINK_WARNING, "The destination of a packet in the route() function is unreachable. Dropping packet.\n");
+ return;
+ }
- subnet = lookup_subnet_mac((mac_t *)(&packet->data[0]));
+ if(dest == source) {
+ logger(mesh, MESHLINK_ERROR, "Routing loop for packet from %s!", source->name);
+ return;
+ }
- 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;
- }
+ send_packet(mesh, dest, packet);
+ return;
}
projects / meshlink / blobdiff