check keyspace distance and inform not found when next peer is not closer than previous peer

include/llarp/dht/context.hpp

@@ -74,7 +74,7 @@ namespace llarp
       Validate(const V& value) const = 0;
 
       void
-      OnFound(const Key_t& askedPeer, const V& value)
+      OnFound(const Key_t askedPeer, const V& value)
       {
         peersAsked.insert(askedPeer);
         if(Validate(value))
@@ -98,18 +98,23 @@ namespace llarp
         Key_t peer;
         if(next)
         {
-          peer = *next.get();
+          // explicit next peer provided
+          peer = next->data();
         }
-        else
+        else if(!GetNextPeer(peer, peersAsked))
         {
-          if(!GetNextPeer(peer, peersAsked))
-          {
-            // no more peers
-            SendReply();
-            return false;
-          }
+          // no more peers
+          return false;
         }
 
+        const Key_t targetKey = target.data();
+        if((prevPeer ^ targetKey) < (peer ^ targetKey))
+        {
+          // next peer is not closer
+          return false;
+        }
+        else
+          peersAsked.insert(peer);
         DoNextRequest(peer);
         return true;
       }
@@ -316,12 +321,11 @@ namespace llarp
           auto txitr     = tx.find(from);
           if(txitr == tx.end())
             return;
-          if(next)
-          {
-            // ask for next peer
-            if(txitr->second->AskNextPeer(from.node, next))
-              sendReply = false;
-          }
+
+          // ask for next peer
+          if(txitr->second->AskNextPeer(from.node, next))
+            sendReply = false;
+
           llarp::LogWarn("Target key ", txitr->second->target);
           Inform(from, txitr->second->target, {}, sendReply, sendReply);
         }

llarp/dht/context.cpp

@@ -339,36 +339,6 @@ namespace llarp
         return true;
       }
 
-      void
-      DoNextRequest(const Key_t &nextPeer)
-      {
-        // iterate to next peer
-        parent->LookupIntroSetIterative(
-            target, whoasked.node, whoasked.txid, nextPeer,
-            std::bind(&ServiceAddressLookup::HandleNextRequestResult, this,
-                      std::placeholders::_1));
-      }
-
-      void
-      HandleNextRequestResult(const std::vector< service::IntroSet > &results)
-      {
-        // merge results
-        std::set< service::IntroSet > found;
-
-        for(const auto &introset : valuesFound)
-          found.insert(introset);
-
-        for(const auto &introset : results)
-          found.insert(introset);
-
-        valuesFound.clear();
-        for(const auto &introset : found)
-          valuesFound.push_back(introset);
-
-        // send reply
-        SendReply();
-      }
-
       bool
       GetNextPeer(Key_t &next, const std::set< Key_t > &exclude)
       {
@@ -383,6 +353,17 @@ namespace llarp
                           new FindIntroMessage(peer.txid, target, R));
       }
 
+      void
+      DoNextRequest(const Key_t &ask) override
+      {
+        if(R)
+          parent->LookupIntroSetRecursive(target, whoasked.node, whoasked.txid,
+                                          ask, R - 1);
+        else
+          parent->LookupIntroSetIterative(target, whoasked.node, whoasked.txid,
+                                          ask);
+      }
+
       virtual void
       SendReply()
       {
@@ -408,7 +389,7 @@ namespace llarp
       }
 
       void
-      SendReply()
+      SendReply() override
       {
         auto path =
             parent->router->paths.GetByUpstream(parent->OurKey(), localPath);