Try to reply to neighbor solicitation requests.
[tinc] / src / route.c
index cb74832..fc02c67 100644 (file)
@@ -1,7 +1,7 @@
 /*
     route.c -- routing
-    Copyright (C) 2000,2001 Ivo Timmermans <itimmermans@bigfoot.com>,
-                  2000,2001 Guus Sliepen <guus@sliepen.warande.net>
+    Copyright (C) 2000-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
+                  2000-2002 Guus Sliepen <guus@sliepen.warande.net>
 
     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
     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 1.1.2.30 2002/03/11 13:14:53 guus Exp $
 */
 
 #include "config.h"
 
-#ifdef HAVE_FREEBSD
+#if defined(HAVE_FREEBSD) || defined(HAVE_OPENBSD)
  #include <sys/param.h>
 #endif
 #include <sys/socket.h>
 #include <netinet/in.h>
-#include <net/ethernet.h>
+#if defined(HAVE_SOLARIS) || defined(HAVE_OPENBSD)
+ #include <net/if.h>
+ #define ETHER_ADDR_LEN 6
+#else
+ #include <net/ethernet.h>
+#endif
+#include <netinet/ip6.h>
+#include <netinet/icmp6.h>
 #include <netinet/if_ether.h>
 #include <utils.h>
 #include <xalloc.h>
 #include <syslog.h>
+#include <string.h>
+
+#include <avl_tree.h>
 
 #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"
 
 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;
+  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)
+  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;
-//      subnet->lasttime = gettimeofday();
       memcpy(&subnet->net.mac.address, address, sizeof(mac_t));
-      subnet_add(source, subnet);
+      subnet_add(myself, subnet);
 
-      if(debug_lvl >= DEBUG_TRAFFIC)
+      /* And tell all other tinc daemons it's our MAC */
+      
+      for(node = connection_tree->head; node; node = node->next)
         {
-          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);
+          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
 }
 
-connection_t *route_mac(connection_t *source, vpn_packet_t *packet)
+node_t *route_mac(vpn_packet_t *packet)
 {
   subnet_t *subnet;
 cp
   /* Learn source address */
 
-  learn_mac(source, (mac_t *)(&packet->data[6]));
+  learn_mac((mac_t *)(&packet->data[6]));
   
   /* Lookup destination address */
     
@@ -91,20 +136,20 @@ 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
-  dest = ntohl(*((unsigned long*)(&packet->data[30])));
-  
-  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]);
         }
 
@@ -114,15 +159,96 @@ 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(!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;  
+}
+
+void route_neighborsol(vpn_packet_t *packet)
 {
+  struct ip6_hdr *hdr;
+  struct nd_neighbor_solicit *ns;
+  struct nd_opt_hdr *opt;
+  subnet_t *subnet;
 cp
-  if(debug_lvl > DEBUG_NOTHING)
+  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 */
+
+  subnet = lookup_subnet_ipv6((ipv6_t *)&ns->nd_ns_target);
+
+  if(!subnet)
     {
-      syslog(LOG_WARNING, _("Cannot route packet: IPv6 routing not yet implemented"));
-    } 
+      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;
+    }
+
+  /* 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_type = ND_NEIGHBOR_ADVERT;
+  opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
+  
+  write_packet(packet);
 cp
-  return NULL;
 }
 
 void route_arp(vpn_packet_t *packet)
@@ -130,7 +256,6 @@ 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 */
 
@@ -158,10 +283,9 @@ 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)
     {
@@ -190,14 +314,14 @@ 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;
+  node_t *n = NULL;
 cp
   /* FIXME: multicast? */
 
@@ -208,10 +332,15 @@ cp
         switch(type)
           {
             case 0x0800:
-              cl = route_ipv4(packet);
+              n = route_ipv4(packet);
               break;
             case 0x86DD:
-              cl = route_ipv6(packet);
+              n = route_ipv6(packet);
+             if(!n && packet->data[6] == 0x33 && packet->data[7] == 0x33 && packet->data[8] == 0xff)
+               {
+                 route_neighborsol(packet);
+                 return;
+               }
               break;
             case 0x0806:
               route_arp(packet);
@@ -223,14 +352,14 @@ cp
                 }
               return;
            }
-         if(cl)
-           send_packet(cl, packet);
+         if(n)
+           send_packet(n, packet);
          break;
         
       case RMODE_SWITCH:
-        cl = route_mac(myself, packet);
-        if(cl)
-          send_packet(cl, packet);
+        n = route_mac(packet);
+        if(n)
+          send_packet(n, packet);
         else
           broadcast_packet(myself, packet);
         break;
@@ -241,23 +370,64 @@ 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 */
+        {
+          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;
+             }
+
+          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:
-        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]));
+        {
+          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 */
+        broadcast_packet(source, packet);                      /* Spread it on */
+        write_packet(packet);
         break;
     }
-  
-  accept_packet(packet);
 }