Changeset 1329

Timestamp:

02/07/09 16:09:11 (4 years ago)

Author:

ahu

Message:

deal with remote authoritative servers that send back responses w/o a question section, and pass on any errors to appropriate mthreads

Files:

• trunk/pdns/pdns/pdns_recursor.cc (modified) (5 diffs)

trunk/pdns/pdns/pdns_recursor.cc

@@ -1271 +1271 @@
 
   len=recvfrom(fd, data, sizeof(data), 0, (sockaddr *)&fromaddr, &addrlen);
-  //  HTimerSentinel hts=s_timer.getSentinel();
+
   if(len < (int)sizeof(dnsheader)) {
     if(len < 0)
@@ -1296 +1296 @@
   memcpy(&dh, data, sizeof(dh));
   
-  if(!dh.qdcount) // UPC, Nominum?
-    return;
-  
   if(dh.qr) {
     PacketID pident;
@@ -1304 +1301 @@
     pident.id=dh.id;
     pident.fd=fd;
-    pident.domain=questionExpand(data, len, pident.type); // don't copy this from above - we need to do the actual read
+    if(!dh.qdcount) { // UPC, Nominum, very old BIND on FormErr, NSD
+      pident.domain.clear();
+      pident.type = 0;
+    }
+    else {
+      pident.domain=questionExpand(data, len, pident.type); // don't copy this from above - we need to do the actual read
+    }
     string packet;
     packet.assign(data, len);
@@ -1313 +1316 @@
     }
 
-    //    s_timer.stop();
+  retryWithName:
+
     if(!MT->sendEvent(pident, &packet)) {
-      //      s_timer.start();
 //      if(g_logCommonErrors)
-//        L<<Logger::Warning<<"Discarding unexpected packet from "<<fromaddr.toString()<<": "<<pident.type<<endl;
+//      L<<Logger::Warning<<"Discarding unexpected packet from "<<fromaddr.toString()<<": "<<pident.type<<endl;
       g_stats.unexpectedCount++;
       
@@ -1325 +1328 @@
           mthread->key.nearMisses++;
         }
+
+        // be a bit paranoid here since we're weakening our matching
+        if(pident.domain.empty() && !mthread->key.domain.empty() && !pident.type && mthread->key.type && 
+           pident.id  == mthread->key.id && mthread->key.remote == pident.remote) {
+            cerr<<"Empty response, rest matches though, sending to a waiter"<<endl;
+          pident.domain = mthread->key.domain;
+          pident.type = mthread->key.type;
+          g_stats.unexpectedCount--;
+          goto retryWithName;
+        }
       }
     }
     else if(fd >= 0) {
-      //      s_timer.start();
       g_udpclientsocks.returnSocket(fd);
     }