+ * Add test case for recursion (infinite loop) domain compression.

[adns.git] / src / reply.c

diff --git a/src/reply.c b/src/reply.c
index 4b3d74fa6b5ad6427f3f064da00c0ee0ceb5220f..586aff0ca6045dd12a5b9fb94369d792dfdef522 100644 (file)
--- a/src/reply.c
+++ b/src/reply.c
@@ -77,70 +77,84 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen,
     adns__diag(ads,serv,0,"server sent us unknown opcode %d (wanted 0=QUERY)",opcode);
     return;
   }
-  if (!qdcount) {
-    adns__diag(ads,serv,0,"server sent reply without quoting our question");
-    return;
-  } else if (qdcount>1) {
-    adns__diag(ads,serv,0,"server claimed to answer %d questions with one message",
-              qdcount);
-    return;
-  }
-  for (qu= ads->timew.head; qu; qu= nqu) {
-    nqu= qu->next;
-    if (qu->id != id) continue;
-    if (dglen < qu->query_dglen) continue;
-    if (memcmp(qu->query_dgram+DNS_HDRSIZE,
-              dgram+DNS_HDRSIZE,
-              qu->query_dglen-DNS_HDRSIZE))
-      continue;
-    if (viatcp) {
-      if (qu->state != query_tcpsent) continue;
-    } else {
-      if (qu->state != query_tosend) continue;
-      if (!(qu->udpsent & (1<<serv))) continue;
+
+  qu= 0;
+  /* See if we can find the relevant query, or leave qu=0 otherwise ... */   
+
+  if (qdcount == 1) {
+    for (qu= viatcp ? ads->tcpw.head : ads->udpw.head; qu; qu= nqu) {
+      nqu= qu->next;
+      if (qu->id != id) continue;
+      if (dglen < qu->query_dglen) continue;
+      if (memcmp(qu->query_dgram+DNS_HDRSIZE,
+                dgram+DNS_HDRSIZE,
+                qu->query_dglen-DNS_HDRSIZE))
+       continue;
+      if (viatcp) {
+       assert(qu->state == query_tcpw);
+      } else {
+       assert(qu->state == query_tosend);
+       if (!(qu->udpsent & (1<<serv))) continue;
+      }
+      break;
     }
-    break;
-  }
-  if (!qu) {
-    if (ads->iflags & adns_if_debug) {
-      adns__vbuf_init(&tempvb);
-      adns__debug(ads,serv,0,"reply not found, id %02x, query owner %s",
-                 id, adns__diag_domain(ads,serv,0,&tempvb,dgram,dglen,DNS_HDRSIZE));
-      adns__vbuf_free(&tempvb);
+    if (qu) {
+      /* We're definitely going to do something with this query now */
+      if (viatcp) LIST_UNLINK(ads->tcpw,qu);
+      else LIST_UNLINK(ads->udpw,qu);
     }
-    return;
   }
-  anstart= qu->query_dglen;
-  arstart= -1;
-
-  LIST_UNLINK(ads->timew,qu);
-  /* We're definitely going to do something with this query now */
   
+  /* If we're going to ignore the packet, we return as soon as we have
+   * failed the query (if any) and printed the warning message (if
+   * any).
+   */
   switch (rcode) {
   case rcode_noerror:
   case rcode_nxdomain:
     break;
   case rcode_formaterror:
     adns__warn(ads,serv,qu,"server cannot understand our query (Format Error)");
-    adns__query_fail(qu,adns_s_rcodeformaterror);
+    if (qu) adns__query_fail(qu,adns_s_rcodeformaterror);
     return;
   case rcode_servfail:
-    adns__query_fail(qu,adns_s_rcodeservfail);
+    if (qu) adns__query_fail(qu,adns_s_rcodeservfail);
+    else adns__warn(ads,serv,qu,"server failure on unidentifiable query");
     return;
   case rcode_notimp:
     adns__warn(ads,serv,qu,"server claims not to implement our query");
-    adns__query_fail(qu,adns_s_rcodenotimplemented);
+    if (qu) adns__query_fail(qu,adns_s_rcodenotimplemented);
     return;
   case rcode_refused:
     adns__warn(ads,serv,qu,"server refused our query");
-    adns__query_fail(qu,adns_s_rcoderefused);
+    if (qu) adns__query_fail(qu,adns_s_rcoderefused);
     return;
   default:
     adns__warn(ads,serv,qu,"server gave unknown response code %d",rcode);
-    adns__query_fail(qu,adns_s_rcodeunknown);
+    if (qu) adns__query_fail(qu,adns_s_rcodeunknown);
     return;
   }
 
+  if (!qu) {
+    if (!qdcount) {
+      adns__diag(ads,serv,0,"server sent reply without quoting our question");
+    } else if (qdcount>1) {
+      adns__diag(ads,serv,0,"server claimed to answer %d questions with one message",
+                qdcount);
+    } else if (ads->iflags & adns_if_debug) {
+      adns__vbuf_init(&tempvb);
+      adns__debug(ads,serv,0,"reply not found, id %02x, query owner %s",
+                 id, adns__diag_domain(ads,serv,0,&tempvb,dgram,dglen,DNS_HDRSIZE));
+      adns__vbuf_free(&tempvb);
+    }
+    return;
+  }
+
+  /* We're definitely going to do something with this packet and this query now. */
+  
+  anstart= qu->query_dglen;
+  arstart= -1;
+
   /* Now, take a look at the answer section, and see if it is complete.
    * If it has any CNAMEs we stuff them in the answer.
    */
@@ -184,7 +198,7 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen,
        qu->cname_begin= rdstart;
        qu->cname_dglen= dglen;
        st= adns__parse_domain(ads,serv,qu, &qu->vb,
-                              qu->flags & adns_qf_quoteok_cname ? pdf_quoteok : 0,
+                              qu->flags & adns_qf_quotefail_cname ? 0 : pdf_quoteok,
                               dgram,dglen, &rdstart,rdstart+rdlength);
        if (!qu->vb.used) goto x_truncated;
        if (st) { adns__query_fail(qu,st); return; }
@@ -318,7 +332,7 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen,
 
   /* This may have generated some child queries ... */
   if (qu->children.head) {
-    qu->state= query_child;
+    qu->state= query_childw;
     LIST_LINK_TAIL(ads->childw,qu);
     return;
   }
@@ -349,7 +363,8 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen,
     memcpy(newquery,qu->vb.buf,qu->vb.used);
   }
   
-  if (qu->state == query_tcpsent) qu->state= query_tosend;
+  if (qu->state == query_tcpw) qu->state= query_tosend;
+  qu->retries= 0;
   adns__reset_preserved(qu);
   adns__query_send(qu,now);
 }