1 files changed, 29 insertions, 4 deletions

diff --git a/src/main.cpp b/src/main.cpp
index 183dff6d3..e16887fa4 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -54,7 +54,6 @@ bool fTxIndex = false;
 bool fIsBareMultisigStd = true;
 unsigned int nCoinCacheSize = 5000;
 
-
 /** Fees smaller than this (in satoshi) are considered zero fee (for relaying and mining) */
 CFeeRate minRelayTxFee = CFeeRate(1000);
 
@@ -3088,10 +3087,31 @@ bool CVerifyDB::VerifyDB(CCoinsView *coinsview, int nCheckLevel, int nCheckDepth
 
 void UnloadBlockIndex()
 {
-    mapBlockIndex.clear();
+    LOCK(cs_main);
     setBlockIndexCandidates.clear();
     chainActive.SetTip(NULL);
     pindexBestInvalid = NULL;
+    pindexBestHeader = NULL;
+    mempool.clear();
+    mapOrphanTransactions.clear();
+    mapOrphanTransactionsByPrev.clear();
+    nSyncStarted = 0;
+    mapBlocksUnlinked.clear();
+    vinfoBlockFile.clear();
+    nLastBlockFile = 0;
+    nBlockSequenceId = 1;
+    mapBlockSource.clear();
+    mapBlocksInFlight.clear();
+    nQueuedValidatedHeaders = 0;
+    nPreferredDownload = 0;
+    setDirtyBlockIndex.clear();
+    setDirtyFileInfo.clear();
+    mapNodeState.clear();
+
+    BOOST_FOREACH(BlockMap::value_type& entry, mapBlockIndex) {
+        delete entry.second;
+    }
+    mapBlockIndex.clear();
 }
 
 bool LoadBlockIndex()
@@ -4024,7 +4044,12 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
     }
 
 
-    else if (strCommand == "getaddr")
+    // This asymmetric behavior for inbound and outbound connections was introduced
+    // to prevent a fingerprinting attack: an attacker can send specific fake addresses
+    // to users' AddrMan and later request them by sending getaddr messages. 
+    // Making users (which are behind NAT and can only make outgoing connections) ignore 
+    // getaddr message mitigates the attack.
+    else if ((strCommand == "getaddr") && (pfrom->fInbound))
     {
         pfrom->vAddrToSend.clear();
         vector<CAddress> vAddr = addrman.GetAddr();
@@ -4308,7 +4333,7 @@ bool ProcessMessages(CNode* pfrom)
 
         // Read header
         CMessageHeader& hdr = msg.hdr;
-        if (!hdr.IsValid())
+        if (!hdr.IsValid(Params().MessageStart()))
         {
             LogPrintf("PROCESSMESSAGE: ERRORS IN HEADER %s peer=%d\n", SanitizeString(hdr.GetCommand()), pfrom->id);
             continue;