Disconnect peers violating blocks-only mode

If we set fRelay=false in our VERSION message, and a peer sends an INV or TX
message anyway, disconnect. Since we use fRelay=false to minimize bandwidth,
we should not tolerate remaining connected to a peer violating the protocol.

1 files changed, 6 insertions, 2 deletions

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index baf3bc744..4418174f9 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -2266,7 +2266,9 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             {
                 pfrom->AddInventoryKnown(inv);
                 if (fBlocksOnly) {
-                    LogPrint(BCLog::NET, "transaction (%s) inv sent in violation of protocol peer=%d\n", inv.hash.ToString(), pfrom->GetId());
+                    LogPrint(BCLog::NET, "transaction (%s) inv sent in violation of protocol, disconnecting peer=%d\n", inv.hash.ToString(), pfrom->GetId());
+                    pfrom->fDisconnect = true;
+                    return true;
                 } else if (!fAlreadyHave && !fImporting && !fReindex && !::ChainstateActive().IsInitialBlockDownload()) {
                     RequestTx(State(pfrom->GetId()), inv.hash, current_time);
                 }
@@ -2483,9 +2485,11 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
     if (strCommand == NetMsgType::TX) {
         // Stop processing the transaction early if
         // We are in blocks only mode and peer is either not whitelisted or whitelistrelay is off
-        if (!g_relay_txes && !pfrom->HasPermission(PF_RELAY))
+        // or if this peer is supposed to be a block-relay-only peer
+        if ((!g_relay_txes && !pfrom->HasPermission(PF_RELAY)) || (pfrom->m_tx_relay == nullptr))
         {
             LogPrint(BCLog::NET, "transaction sent in violation of protocol peer=%d\n", pfrom->GetId());
+            pfrom->fDisconnect = true;
             return true;
         }