Changeset 1182

Timestamp:

06/03/08 23:21:55 (4 months ago)

Author:

ahu

Message:

fix for the 'self-renewing NS record' as spotted by Darren Gamble

Files:

• trunk/pdns/pdns/recursor_cache.cc (modified) (2 diffs)

trunk/pdns/pdns/recursor_cache.cc

@@ -229 +229 @@
-}
- 
+bool MemRecursorCache::attemptToRefreshNSTTL(const QType& qt, const set<DNSResourceRecord>& content, const CacheEntry& stored)
+{
+  if(!stored.d_auth) {
+//    cerr<<"feel free to scribble non-auth data!"<<endl;
+    return false;
+  }
+
+  if(qt.getCode()!=QType::NS) {
+  //  cerr<<"Not NS record"<<endl;
+    return false;
+  }
+  if(content.size()!=stored.d_records.size()) {
+  //  cerr<<"Not equal number of records"<<endl;
+    return false;
+  }
+  if(stored.d_records.empty())
+    return false;
+
+  if(stored.d_records.begin()->d_ttd > content.begin()->ttl) {
+    // cerr<<"attempt to LOWER TTL - fine by us"<<endl;
+    return false;
+  }
+
+
+ // cerr<<"Returning true - update attempt!\n";
+  return true;
+}
+
-/* the code below is rather tricky - it basically replaces the stuff cached for qname by content, but it is special
-   cased for when inserting identical records with only differing ttls, in which case the entry is not
@@ -254 +282 @@
-    ce.d_records.clear();
-
-/* && !ce.d_auth */
+&& !attemptToRefreshNSTTL(qt, content, ce)
-    ce.d_records.clear(); // clear non-auth data
-    ce.d_auth = true;