Check for short packets from the tun/tap device and from other tinc daemons.

[tinc] / src / net_packet.c

diff --git a/src/net_packet.c b/src/net_packet.c
index e858daa..a989b09 100644 (file)
--- a/src/net_packet.c
+++ b/src/net_packet.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: net_packet.c,v 1.1.2.34 2003/07/17 15:06:26 guus Exp $
+    $Id: net_packet.c,v 1.1.2.41 2003/09/23 20:59:01 guus Exp $
 */
 
 #include "system.h"
@@ -118,6 +118,14 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
 
        cp();
 
+       /* Check packet length */
+
+       if(inpkt->len < sizeof(inpkt->seqno) + myself->maclength) {
+               ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got too short packet from %s (%s)"),
+                                       n->name, n->hostname);
+               return;
+       }
+
        /* Check the message authentication code */
 
        if(myself->digest && myself->maclength) {
@@ -189,6 +197,9 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
                inpkt = outpkt;
        }
 
+       if(n->connection)
+               n->connection->last_ping_time = now;
+
        receive_packet(n, inpkt);
 }
 
@@ -239,7 +250,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *inpkt)
                if(!n->status.waitingforkey)
                        send_req_key(n->nexthop->connection, myself, n);
 
-               n->status.waitingforkey = 1;
+               n->status.waitingforkey = true;
 
                return;
        }
@@ -306,14 +317,12 @@ static void send_udppacket(node_t *n, vpn_packet_t *inpkt)
                priority = origpriority;
                ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Setting outgoing packet priority to %d"), priority);
                if(setsockopt(listen_socket[sock].udp, SOL_IP, IP_TOS, &priority, sizeof(priority)))    /* SO_PRIORITY doesn't seem to work */
-                       logger(LOG_ERR, _("System call `%s' failed: %s"), "setsockopt",
-                                  strerror(errno));
+                       logger(LOG_ERR, _("System call `%s' failed: %s"), "setsockopt", strerror(errno));
        }
 #endif
 
        if((sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa))) < 0) {
-               logger(LOG_ERR, _("Error sending packet to %s (%s): %s"), n->name,
-                          n->hostname, strerror(errno));
+               logger(LOG_ERR, _("Error sending packet to %s (%s): %s"), n->name, n->hostname, strerror(errno));
                return;
        }
 
@@ -323,7 +332,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *inpkt)
 /*
   send a packet to the given vpn ip.
 */
-void send_packet(node_t *n, vpn_packet_t *packet)
+void send_packet(const node_t *n, vpn_packet_t *packet)
 {
        node_t *via;
 
@@ -350,15 +359,15 @@ void send_packet(node_t *n, vpn_packet_t *packet)
                           n->name, via->name, n->via->hostname);
 
        if((myself->options | via->options) & OPTION_TCPONLY) {
-               if(send_tcppacket(via->connection, packet))
-                       terminate_connection(via->connection, 1);
+               if(!send_tcppacket(via->connection, packet))
+                       terminate_connection(via->connection, true);
        } else
                send_udppacket(via, packet);
 }
 
 /* Broadcast a packet using the minimum spanning tree */
 
-void broadcast_packet(node_t *from, vpn_packet_t *packet)
+void broadcast_packet(const node_t *from, vpn_packet_t *packet)
 {
        avl_node_t *node;
        connection_t *c;
@@ -369,7 +378,7 @@ void broadcast_packet(node_t *from, vpn_packet_t *packet)
                           packet->len, from->name, from->hostname);
 
        for(node = connection_tree->head; node; node = node->next) {
-               c = (connection_t *) node->data;
+               c = node->data;
 
                if(c->status.active && c->status.mst && c != from->nexthop->connection)
                        send_packet(c->node, packet);
@@ -386,7 +395,7 @@ void flush_queue(node_t *n)
 
        for(node = n->queue->head; node; node = next) {
                next = node->next;
-               send_udppacket(n, (vpn_packet_t *) node->data);
+               send_udppacket(n, node->data);
                list_delete_node(n->queue, node);
        }
 }
@@ -394,7 +403,6 @@ void flush_queue(node_t *n)
 void handle_incoming_vpn_data(int sock)
 {
        vpn_packet_t pkt;
-       int x, l = sizeof(x);
        char *hostname;
        sockaddr_t from;
        socklen_t fromlen = sizeof(from);
@@ -402,21 +410,9 @@ void handle_incoming_vpn_data(int sock)
 
        cp();
 
-       if(getsockopt(sock, SOL_SOCKET, SO_ERROR, &x, &l) < 0) {
-               logger(LOG_ERR, _("This is a bug: %s:%d: %d:%s"),
-                          __FILE__, __LINE__, sock, strerror(errno));
-               cp_trace();
-               exit(1);
-       }
-
-       if(x) {
-               logger(LOG_ERR, _("Incoming data socket error: %s"), strerror(x));
-               return;
-       }
-
        pkt.len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
 
-       if(pkt.len <= 0) {
+       if(pkt.len < 0) {
                logger(LOG_ERR, _("Receiving packet failed: %s"), strerror(errno));
                return;
        }
@@ -433,8 +429,5 @@ void handle_incoming_vpn_data(int sock)
                return;
        }
 
-       if(n->connection)
-               n->connection->last_ping_time = now;
-
        receive_udppacket(n, &pkt);
 }