Store and use a sanitized subVer

Rebased-from: a946aa8d3ec7009ac670eeb65a525efe5eeb6e84

4 files changed, 17 insertions, 8 deletions

diff --git a/src/main.cpp b/src/main.cpp
index b0a6e36236..f8f194afc5 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3216,8 +3216,10 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
             pfrom->nVersion = 300;
         if (!vRecv.empty())
             vRecv >> addrFrom >> nNonce;
-        if (!vRecv.empty())
+        if (!vRecv.empty()) {
             vRecv >> pfrom->strSubVer;
+            pfrom->cleanSubVer = SanitizeString(pfrom->strSubVer);
+        }
         if (!vRecv.empty())
             vRecv >> pfrom->nStartingHeight;
         if (!vRecv.empty())
@@ -3285,7 +3287,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
 
         pfrom->fSuccessfullyConnected = true;
 
-        printf("receive version message: %s: version %d, blocks=%d, us=%s, them=%s, peer=%s\n", pfrom->strSubVer.c_str(), pfrom->nVersion, pfrom->nStartingHeight, addrMe.ToString().c_str(), addrFrom.ToString().c_str(), pfrom->addr.ToString().c_str());
+        printf("receive version message: %s: version %d, blocks=%d, us=%s, them=%s, peer=%s\n", pfrom->cleanSubVer.c_str(), pfrom->nVersion, pfrom->nStartingHeight, addrMe.ToString().c_str(), addrFrom.ToString().c_str(), pfrom->addr.ToString().c_str());
 
         cPeerBlockCounts.input(pfrom->nStartingHeight);
     }
@@ -3534,7 +3536,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
             vEraseQueue.push_back(inv.hash);
 
             printf("AcceptToMemoryPool: %s %s : accepted %s (poolsz %"PRIszu")\n",
-                pfrom->addr.ToString().c_str(), pfrom->strSubVer.c_str(),
+                pfrom->addr.ToString().c_str(), pfrom->cleanSubVer.c_str(),
                 tx.GetHash().ToString().c_str(),
                 mempool.mapTx.size());
 
@@ -3587,7 +3589,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
         if (state.IsInvalid(nDoS))
         {
             printf("%s from %s %s was not accepted into the memory pool\n", tx.GetHash().ToString().c_str(),
-                pfrom->addr.ToString().c_str(), pfrom->strSubVer.c_str());
+                pfrom->addr.ToString().c_str(), pfrom->cleanSubVer.c_str());
             if (nDoS > 0)
                 pfrom->Misbehaving(nDoS);
         }
diff --git a/src/net.cpp b/src/net.cpp
index e5f85d3290..f40afde20f 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -612,7 +612,7 @@ void CNode::copyStats(CNodeStats &stats)
     X(nTimeConnected);
     X(addrName);
     X(nVersion);
-    X(strSubVer);
+    X(cleanSubVer);
     X(fInbound);
     X(nStartingHeight);
     X(nMisbehavior);
diff --git a/src/net.h b/src/net.h
index 6f315f74fd..dfdd3c8137 100644
--- a/src/net.h
+++ b/src/net.h
@@ -98,7 +98,7 @@ public:
     int64 nTimeConnected;
     std::string addrName;
     int nVersion;
-    std::string strSubVer;
+    std::string cleanSubVer;
     bool fInbound;
     int nStartingHeight;
     int nMisbehavior;
@@ -177,7 +177,11 @@ public:
     std::string addrName;
     CService addrLocal;
     int nVersion;
-    std::string strSubVer;
+    // strSubVer is whatever byte array we read from the wire. However, this field is intended 
+    // to be printed out, displayed to humans in various forms and so on. So we sanitize it and
+    // store the sanitized version in cleanSubVer. The original should be used when dealing with
+    // the network or wire types and the cleaned string used when displayed or logged.
+    std::string strSubVer, cleanSubVer;
     bool fOneShot;
     bool fClient;
     bool fInbound;
diff --git a/src/rpcnet.cpp b/src/rpcnet.cpp
index 644c2675ae..99b94ffa3a 100644
--- a/src/rpcnet.cpp
+++ b/src/rpcnet.cpp
@@ -55,7 +55,10 @@ Value getpeerinfo(const Array& params, bool fHelp)
         obj.push_back(Pair("bytesrecv", (boost::int64_t)stats.nRecvBytes));
         obj.push_back(Pair("conntime", (boost::int64_t)stats.nTimeConnected));
         obj.push_back(Pair("version", stats.nVersion));
-        obj.push_back(Pair("subver", stats.strSubVer));
+        // Use the sanitized form of subver here, to avoid tricksy remote peers from
+        // corrupting or modifiying the JSON output by putting special characters in
+        // their ver message.
+        obj.push_back(Pair("subver", stats.cleanSubVer));
         obj.push_back(Pair("inbound", stats.fInbound));
         obj.push_back(Pair("startingheight", stats.nStartingHeight));
         obj.push_back(Pair("banscore", stats.nMisbehavior));