Better handling of late packets.

[tinc] / src / net_packet.c

diff --git a/src/net_packet.c b/src/net_packet.c
index 07f578e..724eaa3 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 1.1.2.26 2003/03/28 13:41:49 guus Exp $
+    $Id: net_packet.c,v 1.1.2.27 2003/04/18 21:18:36 guus Exp $
 */
 
 #include "config.h"
@@ -95,6 +95,7 @@ void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
        int outlen, outpad;
        long int complen = MTU + 12;
        char hmac[EVP_MAX_MD_SIZE];
+       int i;
 
        cp();
 
@@ -133,16 +134,26 @@ void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
        inpkt->len -= sizeof(inpkt->seqno);
        inpkt->seqno = ntohl(inpkt->seqno);
 
-       if(inpkt->seqno <= n->received_seqno) {
-               if(debug_lvl >= DEBUG_TRAFFIC)
-                       syslog(LOG_DEBUG,
-                                  _("Got late or replayed packet from %s (%s), seqno %d"),
-                                  n->name, n->hostname, inpkt->seqno);
-               return;
+       if(inpkt->seqno != n->received_seqno + 1) {
+               if(inpkt->seqno >= n->received_seqno + sizeof(n->late) * 8) {
+                       if(debug_lvl >= DEBUG_TRAFFIC)
+                               syslog(LOG_WARNING, _("Lost %d packets from %s (%s)"),
+                                          inpkt->seqno - n->received_seqno - 1, n->name, n->hostname);
+                       
+                       memset(n->late, 0, sizeof(n->late));
+               } else if (inpkt->seqno <= n->received_seqno) {
+                       if(inpkt->seqno <= n->received_seqno - sizeof(n->late) * 8 || !(n->late[(inpkt->seqno / 8) % sizeof(n->late)] & (1 << inpkt->seqno % 8))) {
+                               syslog(LOG_WARNING, _("Got late or replayed packet from %s (%s), seqno %d, last received %d"),
+                                          n->name, n->hostname, inpkt->seqno, n->received_seqno, n->late[(inpkt->seqno / 8) % sizeof(n->late)]);
+                       } else
+                               for(i = n->received_seqno + 1; i < inpkt->seqno; i++)
+                                       n->late[(inpkt->seqno / 8) % sizeof(n->late)] |= 1 << i % 8;
+               }
        }
-
+       
        n->received_seqno = inpkt->seqno;
-
+       n->late[(n->received_seqno / 8) % sizeof(n->late)] &= ~(1 << n->received_seqno % 8);
+                       
        if(n->received_seqno > MAX_SEQNO)
                keyexpires = 0;