Instead of DoS banning for invalid blocks, merely disconnect nodes if…

… we're relying on them as a primary node Github-Pull: bitcoin#10593 Rebased-From: 35433a2
luke-jr · Jun 15, 2017 · 73ad56d · 73ad56d
1 parent 09566ee
commit 73ad56d
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Showing 2 changed files with 43 additions and 6 deletions.
diff --git a/src/net.h b/src/net.h
@@ -807,6 +807,11 @@ class CNode
         return nLocalServices;
     }
 
+    bool PunishInvalidBlocks() const
+    {
+        return !(fInbound || fFeeler || fWhitelisted || fAddnode);
+    }
+
     std::string GetAddrName() const;
     //! Sets the addrName only if it was not previously set
     void MaybeSetAddrName(const std::string& addrNameIn);

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
@@ -847,6 +847,30 @@ void PeerLogicValidation::UpdatedBlockTip(const CBlockIndex *pindexNew, const CB
     nTimeBestReceived = GetTime();
 }
 
+namespace {
+
+void HandleBlockDoS(std::string node_name, CNode * const pfrom, const int nDoS, const bool is_header) {
+    // We never actually DoS ban for invalid blocks, merely disconnect nodes if we're relying on them as a primary node
+    NodeId node_id = pfrom->GetId();
+    if (node_name.empty()) {
+        node_name = "(unknown)";
+        LOCK(cs_main);
+        CNodeState *nodestate = State(node_id);
+        if (nodestate) {
+            node_name = nodestate->name;
+        }
+    }
+    const std::string msg = strprintf("%s peer=%d got DoS score %d on invalid block%s", node_name, node_id, nDoS, is_header ? " header" : "");
+    if (pfrom->PunishInvalidBlocks()) {
+        LogPrint("net", "%s; simply disconnecting\n", msg);
+        pfrom->fDisconnect = true;
+    } else {
+        LogPrint("net", "%s; tolerating\n", msg);
+    }
+}
+
+}
+
 void PeerLogicValidation::BlockChecked(const CBlock& block, const CValidationState& state) {
     LOCK(cs_main);
 
@@ -857,10 +881,16 @@ void PeerLogicValidation::BlockChecked(const CBlock& block, const CValidationSta
     if (state.IsInvalid(nDoS)) {
         if (it != mapBlockSource.end() && State(it->second.first)) {
             assert (state.GetRejectCode() < REJECT_INTERNAL); // Blocks are never rejected with internal reject codes
+            const NodeId node_id = it->second.first;
+            CNodeState * const nodestate = State(node_id);
             CBlockReject reject = {(unsigned char)state.GetRejectCode(), state.GetRejectReason().substr(0, MAX_REJECT_MESSAGE_LENGTH), hash};
             State(it->second.first)->rejects.push_back(reject);
-            if (nDoS > 0 && it->second.second)
-                Misbehaving(it->second.first, nDoS);
+            if (nDoS > 0 && it->second.second) {
+                connman->ForNode(node_id, [nodestate, nDoS](CNode* pfrom){
+                    HandleBlockDoS(nodestate->name, pfrom, nDoS, false);
+                    return true;
+                });
+            }
         }
     }
     // Check that:
@@ -1974,8 +2004,7 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             int nDoS;
             if (state.IsInvalid(nDoS)) {
                 if (nDoS > 0) {
-                    LOCK(cs_main);
-                    Misbehaving(pfrom->GetId(), nDoS);
+                    HandleBlockDoS("", pfrom, nDoS, true);
                 }
                 LogPrintf("Peer %d sent us invalid header via cmpctblock\n", pfrom->id);
                 return true;
@@ -2275,6 +2304,10 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             // we can use this peer to download.
             UpdateBlockAvailability(pfrom->GetId(), headers.back().GetHash());
 
+            if (pfrom->PunishInvalidBlocks()) {
+                pfrom->fDisconnect = true;
+            }
+
             return true;
         }
         }
@@ -2284,8 +2317,7 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             int nDoS;
             if (state.IsInvalid(nDoS)) {
                 if (nDoS > 0) {
-                    LOCK(cs_main);
-                    Misbehaving(pfrom->GetId(), nDoS);
+                    HandleBlockDoS("", pfrom, nDoS, true);
                 }
                 return error("invalid header received");
             }