Only send one GetAddr response per connection.

This conserves resources from abusive peers that just send
 getaddr in a loop. Also makes correlating addr messages
 against INVs less effective.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/main.cpp b/src/main.cpp
index f5c7e11d6e..df494b226d 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -5214,6 +5214,14 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
             return true;
         }
 
+        // Only send one GetAddr response per connection to reduce resource waste
+        //  and discourage addr stamping of INV announcements.
+        if (pfrom->fSentAddr) {
+            LogPrint("net", "Ignoring repeated \"getaddr\". peer=%d\n", pfrom->id);
+            return true;
+        }
+        pfrom->fSentAddr = true;
+
         pfrom->vAddrToSend.clear();
         vector<CAddress> vAddr = addrman.GetAddr();
         BOOST_FOREACH(const CAddress &addr, vAddr)