Better length checks.

[tinc] / src / route.c

diff --git a/src/route.c b/src/route.c
index 16d932d..e9e07f6 100644 (file)
--- a/src/route.c
+++ b/src/route.c
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-    $Id: route.c,v 1.1.2.64 2003/08/28 21:05:11 guus Exp $
+    $Id: route.c,v 1.1.2.66 2003/10/01 09:14:01 guus Exp $
 */
 
 #include "system.h"
@@ -532,6 +532,11 @@ void route_outgoing(vpn_packet_t *packet)
 
        cp();
 
+       if(packet->len < 14) {
+               ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+               return;
+       }
+
        /* FIXME: multicast? */
 
        switch (routing_mode) {
@@ -539,11 +544,21 @@ void route_outgoing(vpn_packet_t *packet)
                        type = ntohs(*((uint16_t *)(&packet->data[12])));
                        switch (type) {
                                case 0x0800:
+                                       if(packet->len < 34) {
+                                               ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+                                               return;
+                                       }
+
                                        n = route_ipv4(packet);
                                        break;
 
                                case 0x86DD:
-                                       if(packet->data[20] == IPPROTO_ICMPV6 && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
+                                       if(packet->len < 54) {
+                                               ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+                                               return;
+                                       }
+
+                                       if(packet->data[20] == IPPROTO_ICMPV6 && packet->len >= 62 && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
                                                route_neighborsol(packet);
                                                return;
                                        }
@@ -551,6 +566,11 @@ void route_outgoing(vpn_packet_t *packet)
                                        break;
 
                                case 0x0806:
+                                       if(packet->len < 42) {
+                                               ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+                                               return;
+                                       }
+
                                        route_arp(packet);
                                        return;
 
@@ -578,6 +598,12 @@ void route_outgoing(vpn_packet_t *packet)
 
 void route_incoming(node_t *source, vpn_packet_t *packet)
 {
+       if(packet->len < 14) {
+               ifdebug(TRAFFIC) logger(LOG_WARNING, _("Got too short packet from %s (%s)"),
+                                       source->name, source->hostname);
+               return;
+       }
+
        switch (routing_mode) {
                case RMODE_ROUTER:
                        {
@@ -587,10 +613,20 @@ void route_incoming(node_t *source, vpn_packet_t *packet)
                                type = ntohs(*((uint16_t *)(&packet->data[12])));
                                switch (type) {
                                        case 0x0800:
+                                               if(packet->len < 34) {
+                                                       ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+                                                       return;
+                                               }
+
                                                n = route_ipv4(packet);
                                                break;
 
                                        case 0x86DD:
+                                               if(packet->len < 54) {
+                                                       ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
+                                                       return;
+                                               }
+
                                                n = route_ipv6(packet);
                                                break;