Merge pull request #275 from majestrate/staging

disable CNAME RR for random.snode A record lookups

llarp/dns/message.cpp

@@ -256,6 +256,8 @@ namespace llarp
         if(question.qtype != qTypeAAAA)
         {
           hdr_fields |= flags_RCODENameError;
+          if(question.qtype == qTypeA)
+          {
             answers.emplace_back();
             auto& nx    = answers.back();
             nx.rr_name  = question.qname;
@@ -267,6 +269,7 @@ namespace llarp
           }
         }
       }
+    }
 
   }  // namespace dns
 }  // namespace llarp

llarp/handlers/tun.cpp

@@ -199,7 +199,7 @@ namespace llarp
     TunEndpoint::HandleHookedDNSMessage(
         dns::Message &&msg, std::function< void(dns::Message) > reply)
     {
-      //llarp::LogInfo("Tun.HandleHookedDNSMessage ", msg.questions[0].qname);
+      // llarp::LogInfo("Tun.HandleHookedDNSMessage ", msg.questions[0].qname);
       if(msg.questions.size() != 1)
       {
         llarp::LogWarn("bad number of dns questions: ", msg.questions.size());
@@ -244,6 +244,7 @@ namespace llarp
         }
         else
           msg.AddNXReply();
+        reply(msg);
       }
       else if(msg.questions[0].qtype == dns::qTypeA)
       {
@@ -252,10 +253,7 @@ namespace llarp
         if(msg.questions[0].qname == "random.snode"
            || msg.questions[0].qname == "random.snode.")
         {
-          RouterID random;
+          // don't reply to A queries, applications MUST use CNAME queries
-          if(Router()->GetRandomGoodRouter(random))
-            msg.AddCNAMEReply(random.ToString(), 1);
-          else
           msg.AddNXReply();
         }
         else if(msg.questions[0].qname == "localhost.loki"
@@ -297,7 +295,7 @@ namespace llarp
           // TODO: add hook to EnsurePathToSNode
           EnsurePathToSNode(addr.as_array());
           huint32_t ip = ObtainIPForAddr(addr, true);
-          if (ip.h)
+          if(ip.h)
             msg.AddINReply(ip);
           else
           {
@@ -357,7 +355,7 @@ namespace llarp
         // always hook mx records
         if(msg.questions[0].qtype == llarp::dns::qTypeMX)
           return true;
-        // hook random.snode for CNAME
+        // hook random.snode
         if(msg.questions[0].qname == "random.snode"
            || msg.questions[0].qname == "random.snode.")
           return true;