wallet: Force distinct destinations in CWallet::CreateTransaction

promag · promag · commit e82d17991418 · 2018-02-13T01:05:46.000Z
Check that all transaction destinations, including change address
if specified, are distinct.
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
@@ -2701,8 +2701,21 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CWalletT
     CAmount nValue = 0;
     int nChangePosRequest = nChangePosInOut;
     unsigned int nSubtractFeeFromAmount = 0;
+    std::set<CTxDestination> destinations;
+
+    if (!boost::get<CNoDestination>(&coin_control.destChange)) {
+        destinations.insert(coin_control.destChange);
+    }
+
     for (const auto& recipient : vecSend)
     {
+        CTxDestination destination;
+        if (ExtractDestination(recipient.scriptPubKey, destination) &&
+            !destinations.insert(destination).second) {
+            strFailReason = _("Transaction destinations must be distinct");
+            return false;
+        }
+
         if (nValue < 0 || recipient.nAmount < 0)
         {
             strFailReason = _("Transaction amounts must not be negative");
diff --git a/test/functional/rpc_fundrawtransaction.py b/test/functional/rpc_fundrawtransaction.py
@@ -200,11 +200,14 @@ def run_test(self):
         utx = get_unspent(self.nodes[2].listunspent(), 5)
 
         inputs  = [ {'txid' : utx['txid'], 'vout' : utx['vout']} ]
-        outputs = { self.nodes[0].getnewaddress() : Decimal(4.0) }
+        address = self.nodes[0].getnewaddress()
+        outputs = { address : Decimal(4.0) }
         rawtx   = self.nodes[2].createrawtransaction(inputs, outputs)
         dec_tx  = self.nodes[2].decoderawtransaction(rawtx)
         assert_equal(utx['txid'], dec_tx['vin'][0]['txid'])
 
+        assert_raises_rpc_error(-4, "Transaction destinations must be distinct", self.nodes[2].fundrawtransaction, rawtx, {'changeAddress':address})
+
         change = self.nodes[2].getnewaddress()
         assert_raises_rpc_error(-8, "changePosition out of bounds", self.nodes[2].fundrawtransaction, rawtx, {'changeAddress':change, 'changePosition':2})
         rawtxfund = self.nodes[2].fundrawtransaction(rawtx, {'changeAddress': change, 'changePosition': 0})
