25 files changed, 442 insertions, 61 deletions
diff --git a/doc/release-notes.md b/doc/release-notes.md
index f7958381b6..96c830d177 100644
--- a/doc/release-notes.md
+++ b/doc/release-notes.md
@@ -215,6 +215,24 @@ of just announcing the hash. In a reorganization, all new headers are sent,
 instead of just the new tip. This can often prevent an extra roundtrip before
 the actual block is downloaded.
 
+Negative confirmations and conflict detection
+---------------------------------------------
+
+The wallet will now report a negative number for confirmations that indicates
+how deep in the block chain the conflict is found. For example, if a transaction
+A has 5 confirmations and spends the same input as a wallet transaction B, B
+will be reported as having -5 confirmations. If another wallet transaction C
+spends an output from B, it will also be reported as having -5 confirmations.
+To detect conflicts with historical transactions in the chain a one-time
+`-rescan` may be needed.
+
+Unlike earlier versions, unconfirmed but non-conflicting transactions will never
+get a negative confirmation count. They are not treated as spendable unless
+they're coming from ourself (change) and accepted into our local mempool,
+however. The new "trusted" field in the `listtransactions` RPC output
+indicates whether outputs of an unconfirmed transaction are considered
+spendable.
+
 0.12.0 Change log
 =================
 
diff --git a/qa/pull-tester/rpc-tests.py b/qa/pull-tester/rpc-tests.py
index 5004b09c18..598567e5a3 100755
--- a/qa/pull-tester/rpc-tests.py
+++ b/qa/pull-tester/rpc-tests.py
@@ -22,6 +22,7 @@ For a description of arguments recognized by test scripts, see
 """
 
 import os
+import time
 import shutil
 import sys
 import subprocess
@@ -47,6 +48,10 @@ opts = set()
 passOn = ""
 p = re.compile("^--")
 
+bold = ("","")
+if (os.name == 'posix'):
+    bold = ('\033[0m', '\033[1m')
+
 for arg in sys.argv[1:]:
     if arg == '--coverage':
         ENABLE_COVERAGE = 1
@@ -79,6 +84,7 @@ testScripts = [
     'mempool_spendcoinbase.py',
     'mempool_coinbase_spends.py',
     'httpbasics.py',
+    'multi_rpc.py',
     'zapwallettxes.py',
     'proxy_test.py',
     'merkle_blocks.py',
@@ -92,6 +98,7 @@ testScripts = [
     'blockchain.py',
     'disablewallet.py',
     'sendheaders.py',
+    'keypool.py',
 ]
 testScriptsExt = [
     'bip65-cltv.py',
@@ -105,7 +112,6 @@ testScriptsExt = [
     'pruning.py',
     'forknotify.py',
     'invalidateblock.py',
-    'keypool.py',
 #    'rpcbind_test.py', #temporary, bug in libevent, see #6655
     'smartfees.py',
     'maxblocksinflight.py',
@@ -126,7 +132,7 @@ def runtests():
 
     if ENABLE_COVERAGE:
         coverage = RPCCoverage()
-        print("Initializing coverage directory at %s" % coverage.dir)
+        print("Initializing coverage directory at %s\n" % coverage.dir)
 
     if(ENABLE_WALLET == 1 and ENABLE_UTILS == 1 and ENABLE_BITCOIND == 1):
         rpcTestDir = buildDir + '/qa/rpc-tests/'
@@ -141,10 +147,12 @@ def runtests():
                     or run_extended
                     or testScripts[i] in opts
                     or re.sub(".py$", "", testScripts[i]) in opts ):
-                print("Running testscript " + testScripts[i] + "...")
 
+                print("Running testscript %s%s%s ..." % (bold[1], testScripts[i], bold[0]))
+                time0 = time.time()
                 subprocess.check_call(
                     rpcTestDir + testScripts[i] + flags, shell=True)
+                print("Duration: %s s\n" % (int(time.time() - time0)))
 
                 # exit if help is called so we print just one set of
                 # instructions
@@ -156,12 +164,14 @@ def runtests():
         for i in range(len(testScriptsExt)):
             if (run_extended or testScriptsExt[i] in opts
                     or re.sub(".py$", "", testScriptsExt[i]) in opts):
+
                 print(
                     "Running 2nd level testscript "
-                    + testScriptsExt[i] + "...")
-
+                    + "%s%s%s ..." % (bold[1], testScriptsExt[i], bold[0]))
+                time0 = time.time()
                 subprocess.check_call(
                     rpcTestDir + testScriptsExt[i] + flags, shell=True)
+                print("Duration: %s s\n" % (int(time.time() - time0)))
 
         if coverage:
             coverage.report_rpc_coverage()
diff --git a/qa/rpc-tests/multi_rpc.py b/qa/rpc-tests/multi_rpc.py
new file mode 100755
index 0000000000..62071d426e
--- /dev/null
+++ b/qa/rpc-tests/multi_rpc.py
@@ -0,0 +1,122 @@
+#!/usr/bin/env python2
+# Copyright (c) 2015 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#
+# Test mulitple rpc user config option rpcauth
+#
+
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import *
+import base64
+
+try:
+    import http.client as httplib
+except ImportError:
+    import httplib
+try:
+    import urllib.parse as urlparse
+except ImportError:
+    import urlparse
+
+class HTTPBasicsTest (BitcoinTestFramework):
+    def setup_nodes(self):
+        return start_nodes(4, self.options.tmpdir)
+
+    def setup_chain(self):
+        print("Initializing test directory "+self.options.tmpdir)
+        initialize_chain(self.options.tmpdir)
+        #Append rpcauth to bitcoin.conf before initialization
+        rpcauth = "rpcauth=rt:93648e835a54c573682c2eb19f882535$7681e9c5b74bdd85e78166031d2058e1069b3ed7ed967c93fc63abba06f31144"
+        rpcauth2 = "rpcauth=rt2:f8607b1a88861fac29dfccf9b52ff9f$ff36a0c23c8c62b4846112e50fa888416e94c17bfd4c42f88fd8f55ec6a3137e"
+        with open(os.path.join(self.options.tmpdir+"/node0", "bitcoin.conf"), 'a') as f:
+            f.write(rpcauth+"\n")
+            f.write(rpcauth2+"\n")
+
+    def run_test(self):
+
+        ##################################################
+        # Check correctness of the rpcauth config option #
+        ##################################################
+        url = urlparse.urlparse(self.nodes[0].url)
+
+        #Old authpair
+        authpair = url.username + ':' + url.password
+
+        #New authpair generated via contrib/rpcuser tool
+        rpcauth = "rpcauth=rt:93648e835a54c573682c2eb19f882535$7681e9c5b74bdd85e78166031d2058e1069b3ed7ed967c93fc63abba06f31144"
+        password = "cA773lm788buwYe4g4WT+05pKyNruVKjQ25x3n0DQcM="
+
+        #Second authpair with different username
+        rpcauth2 = "rpcauth=rt2:f8607b1a88861fac29dfccf9b52ff9f$ff36a0c23c8c62b4846112e50fa888416e94c17bfd4c42f88fd8f55ec6a3137e"
+        password2 = "8/F3uMDw4KSEbw96U3CA1C4X05dkHDN2BPFjTgZW4KI="
+        authpairnew = "rt:"+password
+
+        headers = {"Authorization": "Basic " + base64.b64encode(authpair)}
+
+        conn = httplib.HTTPConnection(url.hostname, url.port)
+        conn.connect()
+        conn.request('POST', '/', '{"method": "getbestblockhash"}', headers)
+        resp = conn.getresponse()
+        assert_equal(resp.status==401, False)
+        conn.close()
+        
+        #Use new authpair to confirm both work
+        headers = {"Authorization": "Basic " + base64.b64encode(authpairnew)}
+
+        conn = httplib.HTTPConnection(url.hostname, url.port)
+        conn.connect()
+        conn.request('POST', '/', '{"method": "getbestblockhash"}', headers)
+        resp = conn.getresponse()
+        assert_equal(resp.status==401, False)
+        conn.close()
+
+        #Wrong login name with rt's password
+        authpairnew = "rtwrong:"+password
+        headers = {"Authorization": "Basic " + base64.b64encode(authpairnew)}
+
+        conn = httplib.HTTPConnection(url.hostname, url.port)
+        conn.connect()
+        conn.request('POST', '/', '{"method": "getbestblockhash"}', headers)
+        resp = conn.getresponse()
+        assert_equal(resp.status==401, True)
+        conn.close()
+
+        #Wrong password for rt
+        authpairnew = "rt:"+password+"wrong"
+        headers = {"Authorization": "Basic " + base64.b64encode(authpairnew)}
+
+        conn = httplib.HTTPConnection(url.hostname, url.port)
+        conn.connect()
+        conn.request('POST', '/', '{"method": "getbestblockhash"}', headers)
+        resp = conn.getresponse()
+        assert_equal(resp.status==401, True)
+        conn.close()
+
+        #Correct for rt2
+        authpairnew = "rt2:"+password2
+        headers = {"Authorization": "Basic " + base64.b64encode(authpairnew)}
+
+        conn = httplib.HTTPConnection(url.hostname, url.port)
+        conn.connect()
+        conn.request('POST', '/', '{"method": "getbestblockhash"}', headers)
+        resp = conn.getresponse()
+        assert_equal(resp.status==401, False)
+        conn.close()
+
+        #Wrong password for rt2
+        authpairnew = "rt2:"+password2+"wrong"
+        headers = {"Authorization": "Basic " + base64.b64encode(authpairnew)}
+
+        conn = httplib.HTTPConnection(url.hostname, url.port)
+        conn.connect()
+        conn.request('POST', '/', '{"method": "getbestblockhash"}', headers)
+        resp = conn.getresponse()
+        assert_equal(resp.status==401, True)
+        conn.close()
+
+
+
+if __name__ == '__main__':
+    HTTPBasicsTest ().main ()
diff --git a/qa/rpc-tests/txn_clone.py b/qa/rpc-tests/txn_clone.py
index e8ced0e5bb..b1f603a192 100755
--- a/qa/rpc-tests/txn_clone.py
+++ b/qa/rpc-tests/txn_clone.py
@@ -136,7 +136,7 @@ class TxnMallTest(BitcoinTestFramework):
         tx2 = self.nodes[0].gettransaction(txid2)
         
         # Verify expected confirmations
-        assert_equal(tx1["confirmations"], -1)
+        assert_equal(tx1["confirmations"], -2)
         assert_equal(tx1_clone["confirmations"], 2)
         assert_equal(tx2["confirmations"], 1)
 
diff --git a/qa/rpc-tests/txn_doublespend.py b/qa/rpc-tests/txn_doublespend.py
index 36081127b4..d4665b3d42 100755
--- a/qa/rpc-tests/txn_doublespend.py
+++ b/qa/rpc-tests/txn_doublespend.py
@@ -99,7 +99,7 @@ class TxnMallTest(BitcoinTestFramework):
         # Now give doublespend and its parents to miner:
         self.nodes[2].sendrawtransaction(fund_foo_tx["hex"])
         self.nodes[2].sendrawtransaction(fund_bar_tx["hex"])
-        self.nodes[2].sendrawtransaction(doublespend["hex"])
+        doublespend_txid = self.nodes[2].sendrawtransaction(doublespend["hex"])
         # ... mine a block...
         self.nodes[2].generate(1)
 
@@ -107,14 +107,15 @@ class TxnMallTest(BitcoinTestFramework):
         connect_nodes(self.nodes[1], 2)
         self.nodes[2].generate(1)  # Mine another block to make sure we sync
         sync_blocks(self.nodes)
+        assert_equal(self.nodes[0].gettransaction(doublespend_txid)["confirmations"], 2)
 
         # Re-fetch transaction info:
         tx1 = self.nodes[0].gettransaction(txid1)
         tx2 = self.nodes[0].gettransaction(txid2)
-        
+
         # Both transactions should be conflicted
-        assert_equal(tx1["confirmations"], -1)
-        assert_equal(tx2["confirmations"], -1)
+        assert_equal(tx1["confirmations"], -2)
+        assert_equal(tx2["confirmations"], -2)
 
         # Node0's total balance should be starting balance, plus 100BTC for 
         # two more matured blocks, minus 1240 for the double-spend, plus fees (which are
diff --git a/share/rpcuser/README.md b/share/rpcuser/README.md
new file mode 100644
index 0000000000..7c2c909a42
--- /dev/null
+++ b/share/rpcuser/README.md
@@ -0,0 +1,11 @@
+RPC Tools
+---------------------
+
+### [RPCUser](/share/rpcuser) ###
+
+Create an RPC user login credential.
+
+Usage:
+
+./rpcuser.py <username>
+
diff --git a/share/rpcuser/rpcuser.py b/share/rpcuser/rpcuser.py
new file mode 100755
index 0000000000..9fd176908b
--- /dev/null
+++ b/share/rpcuser/rpcuser.py
@@ -0,0 +1,41 @@
+#!/usr/bin/env python2 
+# Copyright (c) 2015 The Bitcoin Core developers 
+# Distributed under the MIT software license, see the accompanying 
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+import hashlib
+import sys
+import os
+from random import SystemRandom
+import base64
+import hmac
+
+if len(sys.argv) < 2:
+    sys.stderr.write('Please include username as an argument.\n')
+    sys.exit(0)
+
+username = sys.argv[1]
+
+#This uses os.urandom() underneath
+cryptogen = SystemRandom()
+
+#Create 16 byte hex salt
+salt_sequence = [cryptogen.randrange(256) for i in range(16)]
+hexseq = list(map(hex, salt_sequence))
+salt = "".join([x[2:] for x in hexseq])
+
+#Create 32 byte b64 password
+password = base64.urlsafe_b64encode(os.urandom(32))
+
+digestmod = hashlib.sha256
+
+if sys.version_info.major >= 3:
+    password = password.decode('utf-8')
+    digestmod = 'SHA256'
+ 
+m = hmac.new(bytearray(salt, 'utf-8'), bytearray(password, 'utf-8'), digestmod)
+result = m.hexdigest()
+
+print("String to be appended to bitcoin.conf:")
+print("rpcauth="+username+":"+salt+"$"+result)
+print("Your password:\n"+password)
diff --git a/src/coins.cpp b/src/coins.cpp
index f0ea5c0459..723e114708 100644
--- a/src/coins.cpp
+++ b/src/coins.cpp
@@ -243,8 +243,9 @@ bool CCoinsViewCache::HaveInputs(const CTransaction& tx) const
     return true;
 }
 
-double CCoinsViewCache::GetPriority(const CTransaction &tx, int nHeight) const
+double CCoinsViewCache::GetPriority(const CTransaction &tx, int nHeight, CAmount &inChainInputValue) const
 {
+    inChainInputValue = 0;
     if (tx.IsCoinBase())
         return 0.0;
     double dResult = 0.0;
@@ -253,8 +254,9 @@ double CCoinsViewCache::GetPriority(const CTransaction &tx, int nHeight) const
         const CCoins* coins = AccessCoins(txin.prevout.hash);
         assert(coins);
         if (!coins->IsAvailable(txin.prevout.n)) continue;
-        if (coins->nHeight < nHeight) {
+        if (coins->nHeight <= nHeight) {
             dResult += coins->vout[txin.prevout.n].nValue * (nHeight-coins->nHeight);
+            inChainInputValue += coins->vout[txin.prevout.n].nValue;
         }
     }
     return tx.ComputePriority(dResult);
diff --git a/src/coins.h b/src/coins.h
index 99b25de45b..d174422100 100644
--- a/src/coins.h
+++ b/src/coins.h
@@ -456,8 +456,12 @@ public:
     //! Check whether all prevouts of the transaction are present in the UTXO set represented by this view
     bool HaveInputs(const CTransaction& tx) const;
 
-    //! Return priority of tx at height nHeight
-    double GetPriority(const CTransaction &tx, int nHeight) const;
+    /**
+     * Return priority of tx at height nHeight. Also calculate the sum of the values of the inputs
+     * that are already in the chain.  These are the inputs that will age and increase priority as
+     * new blocks are added to the chain.
+     */
+    double GetPriority(const CTransaction &tx, int nHeight, CAmount &inChainInputValue) const;
 
     const CTxOut &GetOutputFor(const CTxIn& input) const;
 
diff --git a/src/httprpc.cpp b/src/httprpc.cpp
index 98ac750bb1..2920aa26f7 100644
--- a/src/httprpc.cpp
+++ b/src/httprpc.cpp
@@ -10,8 +10,12 @@
 #include "util.h"
 #include "utilstrencodings.h"
 #include "ui_interface.h"
+#include "crypto/hmac_sha256.h"
+#include <stdio.h>
+#include "utilstrencodings.h"
 
 #include <boost/algorithm/string.hpp> // boost::trim
+#include <boost/foreach.hpp> //BOOST_FOREACH
 
 /** Simple one-shot callback timer to be used by the RPC mechanism to e.g.
  * re-lock the wellet.
@@ -72,6 +76,50 @@ static void JSONErrorReply(HTTPRequest* req, const UniValue& objError, const Uni
     req->WriteReply(nStatus, strReply);
 }
 
+//This function checks username and password against -rpcauth
+//entries from config file.
+static bool multiUserAuthorized(std::string strUserPass)
+{    
+    if (strUserPass.find(":") == std::string::npos) {
+        return false;
+    }
+    std::string strUser = strUserPass.substr(0, strUserPass.find(":"));
+    std::string strPass = strUserPass.substr(strUserPass.find(":") + 1);
+
+    if (mapMultiArgs.count("-rpcauth") > 0) {
+        //Search for multi-user login/pass "rpcauth" from config
+        BOOST_FOREACH(std::string strRPCAuth, mapMultiArgs["-rpcauth"])
+        {
+            std::vector<std::string> vFields;
+            boost::split(vFields, strRPCAuth, boost::is_any_of(":$"));
+            if (vFields.size() != 3) {
+                //Incorrect formatting in config file
+                continue;
+            }
+
+            std::string strName = vFields[0];
+            if (!TimingResistantEqual(strName, strUser)) {
+                continue;
+            }
+
+            std::string strSalt = vFields[1];
+            std::string strHash = vFields[2];
+
+            unsigned int KEY_SIZE = 32;
+            unsigned char *out = new unsigned char[KEY_SIZE]; 
+            
+            CHMAC_SHA256(reinterpret_cast<const unsigned char*>(strSalt.c_str()), strSalt.size()).Write(reinterpret_cast<const unsigned char*>(strPass.c_str()), strPass.size()).Finalize(out);
+            std::vector<unsigned char> hexvec(out, out+KEY_SIZE);
+            std::string strHashFromPass = HexStr(hexvec);
+
+            if (TimingResistantEqual(strHashFromPass, strHash)) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+
 static bool RPCAuthorized(const std::string& strAuth)
 {
     if (strRPCUserColonPass.empty()) // Belt-and-suspenders measure if InitRPCAuthentication was not called
@@ -81,7 +129,12 @@ static bool RPCAuthorized(const std::string& strAuth)
     std::string strUserPass64 = strAuth.substr(6);
     boost::trim(strUserPass64);
     std::string strUserPass = DecodeBase64(strUserPass64);
-    return TimingResistantEqual(strUserPass, strRPCUserColonPass);
+    
+    //Check if authorized under single-user field
+    if (TimingResistantEqual(strUserPass, strRPCUserColonPass)) {
+        return true;
+    }
+    return multiUserAuthorized(strUserPass);
 }
 
 static bool HTTPReq_JSONRPC(HTTPRequest* req, const std::string &)
@@ -157,6 +210,7 @@ static bool InitRPCAuthentication()
             return false;
         }
     } else {
+        LogPrintf("Config options rpcuser and rpcpassword will soon be deprecated. Locally-run instances may remove rpcuser to use cookie-based auth, or may be replaced with rpcauth. Please see share/rpcuser for rpcauth auth generation.");
         strRPCUserColonPass = mapArgs["-rpcuser"] + ":" + mapArgs["-rpcpassword"];
     }
     return true;
diff --git a/src/init.cpp b/src/init.cpp
index e6ce3d7b59..3fd60abfc2 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -441,7 +441,7 @@ std::string HelpMessage(HelpMessageMode mode)
         strUsage += HelpMessageOpt("-limitdescendantcount=<n>", strprintf("Do not accept transactions if any ancestor would have <n> or more in-mempool descendants (default: %u)", DEFAULT_DESCENDANT_LIMIT));
         strUsage += HelpMessageOpt("-limitdescendantsize=<n>", strprintf("Do not accept transactions if any ancestor would have more than <n> kilobytes of in-mempool descendants (default: %u).", DEFAULT_DESCENDANT_SIZE_LIMIT));
     }
-    string debugCategories = "addrman, alert, bench, coindb, db, lock, rand, rpc, selectcoins, mempool, mempoolrej, net, proxy, prune, http, libevent, zmq"; // Don't translate these and qt below
+    string debugCategories = "addrman, alert, bench, coindb, db, lock, rand, rpc, selectcoins, mempool, mempoolrej, net, proxy, prune, http, libevent, tor, zmq"; // Don't translate these and qt below
     if (mode == HMM_BITCOIN_QT)
         debugCategories += ", qt";
     strUsage += HelpMessageOpt("-debug=<category>", strprintf(_("Output debugging information (default: %u, supplying <category> is optional)"), 0) + ". " +
@@ -491,6 +491,7 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-rpcbind=<addr>", _("Bind to given address to listen for JSON-RPC connections. Use [host]:port notation for IPv6. This option can be specified multiple times (default: bind to all interfaces)"));
     strUsage += HelpMessageOpt("-rpcuser=<user>", _("Username for JSON-RPC connections"));
     strUsage += HelpMessageOpt("-rpcpassword=<pw>", _("Password for JSON-RPC connections"));
+    strUsage += HelpMessageOpt("-rpcauth=<userpw>", _("Username and hashed password for JSON-RPC connections. The field <userpw> comes in the format: <USERNAME>:<SALT>$<HASH>. A canonical python script is included in share/rpcuser. This option can be specified multiple times"));
     strUsage += HelpMessageOpt("-rpcport=<port>", strprintf(_("Listen for JSON-RPC connections on <port> (default: %u or testnet: %u)"), 8332, 18332));
     strUsage += HelpMessageOpt("-rpcallowip=<ip>", _("Allow JSON-RPC connections from specified source. Valid for <ip> are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0) or a network/CIDR (e.g. 1.2.3.4/24). This option can be specified multiple times"));
     strUsage += HelpMessageOpt("-rpcthreads=<n>", strprintf(_("Set the number of threads to service RPC calls (default: %d)"), DEFAULT_HTTP_THREADS));
diff --git a/src/main.cpp b/src/main.cpp
index 33bd2e0ce1..eea53a58de 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -950,9 +950,10 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransa
 
         CAmount nValueOut = tx.GetValueOut();
         CAmount nFees = nValueIn-nValueOut;
-        double dPriority = view.GetPriority(tx, chainActive.Height());
+        CAmount inChainInputValue;
+        double dPriority = view.GetPriority(tx, chainActive.Height(), inChainInputValue);
 
-        CTxMemPoolEntry entry(tx, nFees, GetTime(), dPriority, chainActive.Height(), pool.HasNoInputsOf(tx));
+        CTxMemPoolEntry entry(tx, nFees, GetTime(), dPriority, chainActive.Height(), pool.HasNoInputsOf(tx), inChainInputValue);
         unsigned int nSize = entry.GetTxSize();
 
         // Don't accept it if it can't get into a block
@@ -964,7 +965,7 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransa
         CAmount mempoolRejectFee = pool.GetMinFee(GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000).GetFee(nSize);
         if (mempoolRejectFee > 0 && nFees < mempoolRejectFee) {
             return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "mempool min fee not met", false, strprintf("%d < %d", nFees, mempoolRejectFee));
-        } else if (GetBoolArg("-relaypriority", DEFAULT_RELAYPRIORITY) && nFees < ::minRelayTxFee.GetFee(nSize) && !AllowFree(view.GetPriority(tx, chainActive.Height() + 1))) {
+        } else if (GetBoolArg("-relaypriority", DEFAULT_RELAYPRIORITY) && nFees < ::minRelayTxFee.GetFee(nSize) && !AllowFree(entry.GetPriority(chainActive.Height() + 1))) {
             // Require that free transactions have sufficient priority to be mined in the next block.
             return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "insufficient priority");
         }
@@ -4674,6 +4675,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
         bool fMissingInputs = false;
         CValidationState state;
 
+        pfrom->setAskFor.erase(inv.hash);
         mapAlreadyAskedFor.erase(inv);
 
         if (!AlreadyHave(inv) && AcceptToMemoryPool(mempool, state, tx, true, &fMissingInputs))
@@ -5622,6 +5624,9 @@ bool SendMessages(CNode* pto, bool fSendTrickle)
                     pto->PushMessage("getdata", vGetData);
                     vGetData.clear();
                 }
+            } else {
+                //If we're not going to ask, don't expect a response.
+                pto->setAskFor.erase(inv.hash);
             }
             pto->mapAskFor.erase(pto->mapAskFor.begin());
         }
diff --git a/src/net.cpp b/src/net.cpp
index abc7cbb8f4..e5659efc01 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -2407,8 +2407,12 @@ CNode::~CNode()
 
 void CNode::AskFor(const CInv& inv)
 {
-    if (mapAskFor.size() > MAPASKFOR_MAX_SZ)
+    if (mapAskFor.size() > MAPASKFOR_MAX_SZ || setAskFor.size() > SETASKFOR_MAX_SZ)
         return;
+    // a peer may not have multiple non-responded queue positions for a single inv item
+    if (!setAskFor.insert(inv.hash).second)
+        return;
+
     // We're using mapAskFor as a priority queue,
     // the key is the earliest time the request can be sent
     int64_t nRequestTime;
diff --git a/src/net.h b/src/net.h
index fb299fb0b4..a5a5c770d6 100644
--- a/src/net.h
+++ b/src/net.h
@@ -58,6 +58,8 @@ static const bool DEFAULT_UPNP = false;
 #endif
 /** The maximum number of entries in mapAskFor */
 static const size_t MAPASKFOR_MAX_SZ = MAX_INV_SZ;
+/** The maximum number of entries in setAskFor (larger due to getdata latency)*/
+static const size_t SETASKFOR_MAX_SZ = 2 * MAX_INV_SZ;
 /** The maximum number of peer connections to maintain. */
 static const unsigned int DEFAULT_MAX_PEER_CONNECTIONS = 125;
 /** The default for -maxuploadtarget. 0 = Unlimited */
@@ -389,6 +391,7 @@ public:
     mruset<CInv> setInventoryKnown;
     std::vector<CInv> vInventoryToSend;
     CCriticalSection cs_inventory;
+    std::set<uint256> setAskFor;
     std::multimap<int64_t, CInv> mapAskFor;
     // Used for headers announcements - unfiltered blocks to relay
     // Also protected by cs_inventory
diff --git a/src/rpcrawtransaction.cpp b/src/rpcrawtransaction.cpp
index 3bda459245..1f2d77aef0 100644
--- a/src/rpcrawtransaction.cpp
+++ b/src/rpcrawtransaction.cpp
@@ -62,6 +62,7 @@ void ScriptPubKeyToJSON(const CScript& scriptPubKey, UniValue& out, bool fInclud
 void TxToJSON(const CTransaction& tx, const uint256 hashBlock, UniValue& entry)
 {
     entry.push_back(Pair("txid", tx.GetHash().GetHex()));
+    entry.push_back(Pair("size", (int)::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION)));
     entry.push_back(Pair("version", tx.nVersion));
     entry.push_back(Pair("locktime", (int64_t)tx.nLockTime));
     UniValue vin(UniValue::VARR);
@@ -133,6 +134,7 @@ UniValue getrawtransaction(const UniValue& params, bool fHelp)
             "{\n"
             "  \"hex\" : \"data\",       (string) The serialized, hex-encoded data for 'txid'\n"
             "  \"txid\" : \"id\",        (string) The transaction id (same as provided)\n"
+            "  \"size\" : n,             (numeric) The transaction size\n"
             "  \"version\" : n,          (numeric) The version\n"
             "  \"locktime\" : ttt,       (numeric) The lock time\n"
             "  \"vin\" : [               (array of json objects)\n"
@@ -429,6 +431,7 @@ UniValue decoderawtransaction(const UniValue& params, bool fHelp)
             "\nResult:\n"
             "{\n"
             "  \"txid\" : \"id\",        (string) The transaction id\n"
+            "  \"size\" : n,             (numeric) The transaction size\n"
             "  \"version\" : n,          (numeric) The version\n"
             "  \"locktime\" : ttt,       (numeric) The lock time\n"
             "  \"vin\" : [               (array of json objects)\n"
diff --git a/src/test/policyestimator_tests.cpp b/src/test/policyestimator_tests.cpp
index 1315146f10..644c3da213 100644
--- a/src/test/policyestimator_tests.cpp
+++ b/src/test/policyestimator_tests.cpp
@@ -196,7 +196,7 @@ BOOST_AUTO_TEST_CASE(BlockPolicyEstimates)
 
     // Test that if the mempool is limited, estimateSmartFee won't return a value below the mempool min fee
     // and that estimateSmartPriority returns essentially an infinite value
-    mpool.addUnchecked(tx.GetHash(),  CTxMemPoolEntry(tx, feeV[0][5], GetTime(), priV[1][5], blocknum, mpool.HasNoInputsOf(tx)));
+    mpool.addUnchecked(tx.GetHash(),  entry.Fee(feeV[0][5]).Time(GetTime()).Priority(priV[1][5]).Height(blocknum).FromTx(tx, &mpool));
     // evict that transaction which should set a mempool min fee of minRelayTxFee + feeV[0][5]
     mpool.TrimToSize(1);
     BOOST_CHECK(mpool.GetMinFee(1).GetFeePerK() > feeV[0][5]);
diff --git a/src/test/rpc_tests.cpp b/src/test/rpc_tests.cpp
index 2a486f08e4..ce22975005 100644
--- a/src/test/rpc_tests.cpp
+++ b/src/test/rpc_tests.cpp
@@ -72,6 +72,7 @@ BOOST_AUTO_TEST_CASE(rpc_rawparams)
     BOOST_CHECK_THROW(CallRPC("decoderawtransaction DEADBEEF"), runtime_error);
     string rawtx = "0100000001a15d57094aa7a21a28cb20b59aab8fc7d1149a3bdbcddba9c622e4f5f6a99ece010000006c493046022100f93bb0e7d8db7bd46e40132d1f8242026e045f03a0efe71bbb8e3f475e970d790221009337cd7f1f929f00cc6ff01f03729b069a7c21b59b1736ddfee5db5946c5da8c0121033b9b137ee87d5a812d6f506efdd37f0affa7ffc310711c06c7f3e097c9447c52ffffffff0100e1f505000000001976a9140389035a9225b3839e2bbf32d826a1e222031fd888ac00000000";
     BOOST_CHECK_NO_THROW(r = CallRPC(string("decoderawtransaction ")+rawtx));
+    BOOST_CHECK_EQUAL(find_value(r.get_obj(), "size").get_int(), 193);
     BOOST_CHECK_EQUAL(find_value(r.get_obj(), "version").get_int(), 1);
     BOOST_CHECK_EQUAL(find_value(r.get_obj(), "locktime").get_int(), 0);
     BOOST_CHECK_THROW(r = CallRPC(string("decoderawtransaction ")+rawtx+" extra"), runtime_error);
diff --git a/src/test/test_bitcoin.cpp b/src/test/test_bitcoin.cpp
index 2fe190f885..351870014d 100644
--- a/src/test/test_bitcoin.cpp
+++ b/src/test/test_bitcoin.cpp
@@ -144,8 +144,13 @@ TestChain100Setup::~TestChain100Setup()
 
 
 CTxMemPoolEntry TestMemPoolEntryHelper::FromTx(CMutableTransaction &tx, CTxMemPool *pool) {
-    return CTxMemPoolEntry(tx, nFee, nTime, dPriority, nHeight,
-                           pool ? pool->HasNoInputsOf(tx) : hadNoDependencies);
+    CTransaction txn(tx);
+    bool hasNoDependencies = pool ? pool->HasNoInputsOf(tx) : hadNoDependencies;
+    // Hack to assume either its completely dependent on other mempool txs or not at all
+    CAmount inChainValue = hasNoDependencies ? txn.GetValueOut() : 0;
+
+    return CTxMemPoolEntry(txn, nFee, nTime, dPriority, nHeight,
+                           hasNoDependencies, inChainValue);
 }
 
 void Shutdown(void* parg)
diff --git a/src/torcontrol.cpp b/src/torcontrol.cpp
index 31a2917203..8eccc81e30 100644
--- a/src/torcontrol.cpp
+++ b/src/torcontrol.cpp
@@ -617,7 +617,9 @@ void TorController::disconnected_cb(TorControlConnection& conn)
     service = CService();
     if (!reconnect)
         return;
-    LogPrintf("tor: Disconnected from Tor control port %s, trying to reconnect\n", target);
+
+    LogPrint("tor", "tor: Disconnected from Tor control port %s, trying to reconnect\n", target);
+
     // Single-shot timer for reconnect. Use exponential backoff.
     struct timeval time = MillisToTimeval(int64_t(reconnect_timeout * 1000.0));
     reconnect_ev = event_new(base, -1, 0, reconnect_cb, this);
diff --git a/src/txmempool.cpp b/src/txmempool.cpp
index ec7971c2f1..6d1df0b3d1 100644
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -19,10 +19,10 @@
 using namespace std;
 
 CTxMemPoolEntry::CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
-                                 int64_t _nTime, double _dPriority,
-                                 unsigned int _nHeight, bool poolHasNoInputsOf):
-    tx(_tx), nFee(_nFee), nTime(_nTime), dPriority(_dPriority), nHeight(_nHeight),
-    hadNoDependencies(poolHasNoInputsOf)
+                                 int64_t _nTime, double _entryPriority, unsigned int _entryHeight,
+                                 bool poolHasNoInputsOf, CAmount _inChainInputValue):
+    tx(_tx), nFee(_nFee), nTime(_nTime), entryPriority(_entryPriority), entryHeight(_entryHeight),
+    hadNoDependencies(poolHasNoInputsOf), inChainInputValue(_inChainInputValue)
 {
     nTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
     nModSize = tx.CalculateModifiedSize(nTxSize);
@@ -31,6 +31,8 @@ CTxMemPoolEntry::CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
     nCountWithDescendants = 1;
     nSizeWithDescendants = nTxSize;
     nFeesWithDescendants = nFee;
+    CAmount nValueIn = tx.GetValueOut()+nFee;
+    assert(inChainInputValue <= nValueIn);
 }
 
 CTxMemPoolEntry::CTxMemPoolEntry(const CTxMemPoolEntry& other)
@@ -41,9 +43,10 @@ CTxMemPoolEntry::CTxMemPoolEntry(const CTxMemPoolEntry& other)
 double
 CTxMemPoolEntry::GetPriority(unsigned int currentHeight) const
 {
-    CAmount nValueIn = tx.GetValueOut()+nFee;
-    double deltaPriority = ((double)(currentHeight-nHeight)*nValueIn)/nModSize;
-    double dResult = dPriority + deltaPriority;
+    double deltaPriority = ((double)(currentHeight-entryHeight)*inChainInputValue)/nModSize;
+    double dResult = entryPriority + deltaPriority;
+    if (dResult < 0) // This should only happen if it was called with a height below entry height
+        dResult = 0;
     return dResult;
 }
 
diff --git a/src/txmempool.h b/src/txmempool.h
index 7f43120f7f..c470bbe28f 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -63,9 +63,10 @@ private:
     size_t nModSize; //! ... and modified size for priority
     size_t nUsageSize; //! ... and total memory usage
     int64_t nTime; //! Local time when entering the mempool
-    double dPriority; //! Priority when entering the mempool
-    unsigned int nHeight; //! Chain height when entering the mempool
+    double entryPriority; //! Priority when entering the mempool
+    unsigned int entryHeight; //! Chain height when entering the mempool
     bool hadNoDependencies; //! Not dependent on any other txs when it entered the mempool
+    CAmount inChainInputValue; //! Sum of all txin values that are already in blockchain
 
     // Information about descendants of this transaction that are in the
     // mempool; if we remove this transaction we must remove all of these
@@ -78,15 +79,20 @@ private:
 
 public:
     CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
-                    int64_t _nTime, double _dPriority, unsigned int _nHeight, bool poolHasNoInputsOf = false);
+                    int64_t _nTime, double _entryPriority, unsigned int _entryHeight,
+                    bool poolHasNoInputsOf, CAmount _inChainInputValue);
     CTxMemPoolEntry(const CTxMemPoolEntry& other);
 
     const CTransaction& GetTx() const { return this->tx; }
+    /**
+     * Fast calculation of lower bound of current priority as update
+     * from entry priority. Only inputs that were originally in-chain will age.
+     */
     double GetPriority(unsigned int currentHeight) const;
     const CAmount& GetFee() const { return nFee; }
     size_t GetTxSize() const { return nTxSize; }
     int64_t GetTime() const { return nTime; }
-    unsigned int GetHeight() const { return nHeight; }
+    unsigned int GetHeight() const { return entryHeight; }
     bool WasClearAtEntry() const { return hadNoDependencies; }
     size_t DynamicMemoryUsage() const { return nUsageSize; }
 
diff --git a/src/utiltime.cpp b/src/utiltime.cpp
index 3202c47f1d..7d9f6210eb 100644
--- a/src/utiltime.cpp
+++ b/src/utiltime.cpp
@@ -20,7 +20,9 @@ int64_t GetTime()
 {
     if (nMockTime) return nMockTime;
 
-    return time(NULL);
+    time_t now = time(NULL);
+    assert(now > 0);
+    return now;
 }
 
 void SetMockTime(int64_t nMockTimeIn)
@@ -30,14 +32,18 @@ void SetMockTime(int64_t nMockTimeIn)
 
 int64_t GetTimeMillis()
 {
-    return (boost::posix_time::microsec_clock::universal_time() -
-            boost::posix_time::ptime(boost::gregorian::date(1970,1,1))).total_milliseconds();
+    int64_t now = (boost::posix_time::microsec_clock::universal_time() -
+                   boost::posix_time::ptime(boost::gregorian::date(1970,1,1))).total_milliseconds();
+    assert(now > 0);
+    return now;
 }
 
 int64_t GetTimeMicros()
 {
-    return (boost::posix_time::microsec_clock::universal_time() -
-            boost::posix_time::ptime(boost::gregorian::date(1970,1,1))).total_microseconds();
+    int64_t now = (boost::posix_time::microsec_clock::universal_time() -
+                   boost::posix_time::ptime(boost::gregorian::date(1970,1,1))).total_microseconds();
+    assert(now > 0);
+    return now;
 }
 
 /** Return a time useful for the debug log */
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index b6eaca80b3..a4ab2248a5 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -65,6 +65,8 @@ void WalletTxToJSON(const CWalletTx& wtx, UniValue& entry)
         entry.push_back(Pair("blockhash", wtx.hashBlock.GetHex()));
         entry.push_back(Pair("blockindex", wtx.nIndex));
         entry.push_back(Pair("blocktime", mapBlockIndex[wtx.hashBlock]->GetBlockTime()));
+    } else {
+        entry.push_back(Pair("trusted", wtx.IsTrusted()));
     }
     uint256 hash = wtx.GetHash();
     entry.push_back(Pair("txid", hash.GetHex()));
@@ -1421,7 +1423,9 @@ UniValue listtransactions(const UniValue& params, bool fHelp)
             "    \"fee\": x.xxx,             (numeric) The amount of the fee in " + CURRENCY_UNIT + ". This is negative and only available for the \n"
             "                                         'send' category of transactions.\n"
             "    \"confirmations\": n,       (numeric) The number of confirmations for the transaction. Available for 'send' and \n"
-            "                                         'receive' category of transactions.\n"
+            "                                         'receive' category of transactions. Negative confirmations indicate the\n"
+            "                                         transation conflicts with the block chain\n"
+            "    \"trusted\": xxx            (bool) Whether we consider the outputs of this unconfirmed transaction safe to spend.\n"
             "    \"blockhash\": \"hashvalue\", (string) The block hash containing the transaction. Available for 'send' and 'receive'\n"
             "                                          category of transactions.\n"
             "    \"blockindex\": n,          (numeric) The block index containing the transaction. Available for 'send' and 'receive'\n"
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 2412074be3..30b9869be0 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -607,6 +607,14 @@ bool CWallet::AddToWallet(const CWalletTx& wtxIn, bool fFromLoadWallet, CWalletD
         wtx.BindWallet(this);
         wtxOrdered.insert(make_pair(wtx.nOrderPos, TxPair(&wtx, (CAccountingEntry*)0)));
         AddToSpends(hash);
+        BOOST_FOREACH(const CTxIn& txin, wtx.vin) {
+            if (mapWallet.count(txin.prevout.hash)) {
+                CWalletTx& prevtx = mapWallet[txin.prevout.hash];
+                if (prevtx.nIndex == -1 && !prevtx.hashBlock.IsNull()) {
+                    MarkConflicted(prevtx.hashBlock, wtx.GetHash());
+                }
+            }
+        }
     }
     else
     {
@@ -726,6 +734,20 @@ bool CWallet::AddToWalletIfInvolvingMe(const CTransaction& tx, const CBlock* pbl
 {
     {
         AssertLockHeld(cs_wallet);
+
+        if (pblock) {
+            BOOST_FOREACH(const CTxIn& txin, tx.vin) {
+                std::pair<TxSpends::const_iterator, TxSpends::const_iterator> range = mapTxSpends.equal_range(txin.prevout);
+                while (range.first != range.second) {
+                    if (range.first->second != tx.GetHash()) {
+                        LogPrintf("Transaction %s (in block %s) conflicts with wallet transaction %s (both spend %s:%i)\n", tx.GetHash().ToString(), pblock->GetHash().ToString(), range.first->second.ToString(), range.first->first.hash.ToString(), range.first->first.n);
+                        MarkConflicted(pblock->GetHash(), range.first->second);
+                    }
+                    range.first++;
+                }
+            }
+        }
+
         bool fExisted = mapWallet.count(tx.GetHash()) != 0;
         if (fExisted && !fUpdate) return false;
         if (fExisted || IsMine(tx) || IsFromMe(tx))
@@ -746,9 +768,57 @@ bool CWallet::AddToWalletIfInvolvingMe(const CTransaction& tx, const CBlock* pbl
     return false;
 }
 
+void CWallet::MarkConflicted(const uint256& hashBlock, const uint256& hashTx)
+{
+    LOCK2(cs_main, cs_wallet);
+
+    CBlockIndex* pindex;
+    assert(mapBlockIndex.count(hashBlock));
+    pindex = mapBlockIndex[hashBlock];
+    int conflictconfirms = 0;
+    if (chainActive.Contains(pindex)) {
+        conflictconfirms = -(chainActive.Height() - pindex->nHeight + 1);
+    }
+    assert(conflictconfirms < 0);
+
+    // Do not flush the wallet here for performance reasons
+    CWalletDB walletdb(strWalletFile, "r+", false);
+
+    std::deque<uint256> todo;
+    std::set<uint256> done;
+
+    todo.push_back(hashTx);
+
+    while (!todo.empty()) {
+        uint256 now = todo.front();
+        todo.pop_front();
+        done.insert(now);
+        assert(mapWallet.count(now));
+        CWalletTx& wtx = mapWallet[now];
+        int currentconfirm = wtx.GetDepthInMainChain();
+        if (conflictconfirms < currentconfirm) {
+            // Block is 'more conflicted' than current confirm; update.
+            // Mark transaction as conflicted with this block.
+            wtx.nIndex = -1;
+            wtx.hashBlock = hashBlock;
+            wtx.MarkDirty();
+            wtx.WriteToDisk(&walletdb);
+            // Iterate over all its outputs, and mark transactions in the wallet that spend them conflicted too
+            TxSpends::const_iterator iter = mapTxSpends.lower_bound(COutPoint(now, 0));
+            while (iter != mapTxSpends.end() && iter->first.hash == now) {
+                 if (!done.count(iter->second)) {
+                     todo.push_back(iter->second);
+                 }
+                 iter++;
+            }
+        }
+    }
+}
+
 void CWallet::SyncTransaction(const CTransaction& tx, const CBlock* pblock)
 {
     LOCK2(cs_main, cs_wallet);
+
     if (!AddToWalletIfInvolvingMe(tx, pblock, true))
         return; // Not one of ours
 
@@ -1088,7 +1158,7 @@ void CWallet::ReacceptWalletTransactions()
 
         int nDepth = wtx.GetDepthInMainChain();
 
-        if (!wtx.IsCoinBase() && nDepth < 0) {
+        if (!wtx.IsCoinBase() && nDepth == 0) {
             mapSorted.insert(std::make_pair(wtx.nOrderPos, &wtx));
         }
     }
@@ -1302,6 +1372,14 @@ bool CWalletTx::IsTrusted() const
     if (!bSpendZeroConfChange || !IsFromMe(ISMINE_ALL)) // using wtx's cached debit
         return false;
 
+    // Don't trust unconfirmed transactions from us unless they are in the mempool.
+    {
+        LOCK(mempool.cs);
+        if (!mempool.exists(GetHash())) {
+            return false;
+        }
+    }
+
     // Trusted if all inputs are from us and are in the mempool:
     BOOST_FOREACH(const CTxIn& txin, vin)
     {
@@ -1878,6 +1956,7 @@ bool CWallet::CreateTransaction(const vector<CRecipient>& vecSend, CWalletTx& wt
                     //a chance at a free transaction.
                     //But mempool inputs might still be in the mempool, so their age stays 0
                     int age = pcoin.first->GetDepthInMainChain();
+                    assert(age >= 0);
                     if (age != 0)
                         age += 1;
                     dPriority += (double)nCredit * age;
@@ -2813,9 +2892,9 @@ int CMerkleTx::SetMerkleBranch(const CBlock& block)
     return chainActive.Height() - pindex->nHeight + 1;
 }
 
-int CMerkleTx::GetDepthInMainChainINTERNAL(const CBlockIndex* &pindexRet) const
+int CMerkleTx::GetDepthInMainChain(const CBlockIndex* &pindexRet) const
 {
-    if (hashBlock.IsNull() || nIndex == -1)
+    if (hashBlock.IsNull())
         return 0;
     AssertLockHeld(cs_main);
 
@@ -2828,17 +2907,7 @@ int CMerkleTx::GetDepthInMainChainINTERNAL(const CBlockIndex* &pindexRet) const
         return 0;
 
     pindexRet = pindex;
-    return chainActive.Height() - pindex->nHeight + 1;
-}
-
-int CMerkleTx::GetDepthInMainChain(const CBlockIndex* &pindexRet) const
-{
-    AssertLockHeld(cs_main);
-    int nResult = GetDepthInMainChainINTERNAL(pindexRet);
-    if (nResult == 0 && !mempool.exists(GetHash()))
-        return -1; // Not in chain, not in mempool
-
-    return nResult;
+    return ((nIndex == -1) ? (-1) : 1) * (chainActive.Height() - pindex->nHeight + 1);
 }
 
 int CMerkleTx::GetBlocksToMaturity() const
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index 88bf27498f..859788893c 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -155,11 +155,14 @@ struct COutputEntry
 /** A transaction with a merkle branch linking it to the block chain. */
 class CMerkleTx : public CTransaction
 {
-private:
-    int GetDepthInMainChainINTERNAL(const CBlockIndex* &pindexRet) const;
-
 public:
     uint256 hashBlock;
+
+    /* An nIndex == -1 means that hashBlock (in nonzero) refers to the earliest
+     * block in the chain we know this or any in-wallet dependency conflicts
+     * with. Older clients interpret nIndex == -1 as unconfirmed for backward
+     * compatibility.
+     */
     int nIndex;
 
     CMerkleTx()
@@ -192,16 +195,15 @@ public:
 
     int SetMerkleBranch(const CBlock& block);
 
-
     /**
      * Return depth of transaction in blockchain:
-     * -1  : not in blockchain, and not in memory pool (conflicted transaction)
+     * <0  : conflicts with a transaction this deep in the blockchain
      *  0  : in memory pool, waiting to be included in a block
      * >=1 : this many blocks deep in the main chain
      */
     int GetDepthInMainChain(const CBlockIndex* &pindexRet) const;
     int GetDepthInMainChain() const { const CBlockIndex *pindexRet; return GetDepthInMainChain(pindexRet); }
-    bool IsInMainChain() const { const CBlockIndex *pindexRet; return GetDepthInMainChainINTERNAL(pindexRet) > 0; }
+    bool IsInMainChain() const { const CBlockIndex *pindexRet; return GetDepthInMainChain(pindexRet) > 0; }
     int GetBlocksToMaturity() const;
     bool AcceptToMemoryPool(bool fLimitFree=true, bool fRejectAbsurdFee=true);
 };
@@ -480,6 +482,10 @@ private:
     void AddToSpends(const COutPoint& outpoint, const uint256& wtxid);
     void AddToSpends(const uint256& wtxid);
 
+    /* Mark a transaction (and its in-wallet descendants) as conflicting with a particular block. */
+    void MarkConflicted(const uint256& hashBlock, const uint256& hashTx);
+
+
     void SyncMetaData(std::pair<TxSpends::iterator, TxSpends::iterator>);
 
 public: