From: ian <ian>
Date: Sun, 4 Oct 1998 17:39:42 +0000 (+0000)
Subject: Middle of parsing incoming datagrams.
X-Git-Tag: abandon.1999-04-10.multithread~61
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=adns.git;a=commitdiff_plain;h=ec477b9e0921b754a2edcee988d16a6339be1708

Middle of parsing incoming datagrams.
---

diff --git a/src/adns.h b/src/adns.h
index 90b166b..901ea03 100644
--- a/src/adns.h
+++ b/src/adns.h
@@ -91,13 +91,16 @@ typedef enum {
 typedef enum {
   adns_s_ok,
   adns_s_timeout,
-  adns_s_unknownqtype,
   adns_s_nolocalmem,
   adns_s_allservfail,
+  adns_s_serverfailure,
   adns_s_max_tempfail= 99,
+  adns_s_norecurse,
+  adns_s_serverfaulty,
+  adns_s_max_localmisconfig= 199,
   adns_s_inconsistent, /* PTR gives domain whose A does not match */
   adns_s_cname, /* CNAME found where data eg A expected (not if _qf_loosecname) */
-  adns_s_max_misconfig= 199,
+  adns_s_max_remotemisconfig= 299,
   adns_s_nxdomain,
   adns_s_norecord,
   adns_s_invaliddomain
diff --git a/src/reply.c b/src/reply.c
index 63b7033..6aacd2b 100644
--- a/src/reply.c
+++ b/src/reply.c
@@ -2,7 +2,83 @@
 
 #include "internal.h"
 
+typedef enum {
+  rcode_noerror,
+  rcode_formaterror,
+  rcode_serverfail,
+  rcode_nxdomain,
+  rcode_notimp,
+  rcode_refused
+} dns_rcode;
+
 void adns__procdgram(adns_state ads, const byte *dgram, int len, int serv) {
-  /* FIXME do something with incoming datagrams */
+  unsigned char *rpp;
+  
+  if (len<12) {
+    adns__diag(ads,serv,"received datagram too short for message header (%d)",len);
+    return;
+  }
+  id= GFREPLYW;
+  f1= GFREPLYB;
+  f2= GFREPLYB;
+  qdcount= GFREPLYW;
+  ancount= GFREPLYW;
+  nscount= GFREPLYW;
+  arcount= GFREPLYW;
+
+  if (f1&0x80) {
+    adns__diag(ads,serv,"server sent us a query, not a response");
+    return;
+  }
+  if (f1&0x70) {
+    adns__diag(ads,serv,"server sent us unknown opcode %d (wanted 0=QUERY)",
+	       (f1>>4)&0x70);
+    return;
+  }
+  if (!qdcount) {
+    adns__diag(ads,serv,"server sent reply without quoting our question");
+    return;
+  } else if (qdcount>1) {
+    adns__diag(ads,serv,"server claimed to answer %d questions with one message",
+	       qdcount);
+    return;
+  }
+  for (qu= ads->timew; qu= nqu; qu++) {
+    nqu= qu->next;
+    if (qu->id != id) continue;
+    if (len < qu->querylen) continue;
+    if (memcmp(qu->querymsg+12,rpp,qu->querylen-12)) continue;
+    break;
+  }
+  if (!qu) {
+    adns__debug(ads,serv,"reply not found (id=%02x)",id);
+    return;
+  }
+  if (!(f2&0x80)) {
+    adns__diag(ads,serv,"server is not willing to do recursive lookups for us");
+    adns__query_fail(ads,qu,adns_s_norecurse);
+    return;
+  }
+  if (!(f1&0x01)) {
+    adns__diag(ads,serv,"server thinks we didn't ask for recursive lookup");
+    adns__query_fail(ads,qu,adns_s_serverfaulty);
+    return;
+  }
+  switch (f1&0x0f) {
+  case 0: /* NOERROR */
+    break;
+  case 1: /* Format error */
+    adns__diag(ads,serv,"server cannot understand our query (Format Error)");
+    adns__query_fail(ads,qu,adns_s_serverfaulty);
+    return;
+  case 2: /* Server failure */
+    adns__query_fail(ads,qu,adns_s_serverfailure);
+    return;
+  case 3: /* Name Error */
+  
+  qr= f1&0x80;
+  
+	      
   adns__diag(ads,serv,"received datagram size %d",len);
+
 }