Merge bitcoin#7575: Minimal BIP9 implementation

8c74ced RPC test for BIP9 warning logic (Suhas Daftuar)
7870deb Test versionbits deployments (Suhas Daftuar)
532cbb2 Add testing of ComputeBlockVersion (Suhas Daftuar)
d23f6c6 Softfork status report in RPC (Pieter Wuille)
732e774 Versionbits tests (Pieter Wuille)
6851107 BIP9 Implementation (Pieter Wuille)

qa/pull-tester/rpc-tests.py

@@ -115,6 +115,7 @@
     'invalidblockrequest.py',
     'invalidtxrequest.py',
     'abandonconflict.py',
+    'p2p-versionbits-warning.py',
 ]
 testScriptsExt = [
     'bip65-cltv.py',

qa/rpc-tests/p2p-versionbits-warning.py

@@ -0,0 +1,160 @@
+#!/usr/bin/env python2
+# Copyright (c) 2016 The Bitcoin Core developers
+# Distributed under the MIT/X11 software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+#
+
+from test_framework.mininode import *
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import *
+import time
+from test_framework.blocktools import create_block, create_coinbase
+
+'''
+Test version bits' warning system.
+
+Generate chains with block versions that appear to be signalling unknown
+soft-forks, and test that warning alerts are generated.
+'''
+
+VB_PERIOD = 144 # versionbits period length for regtest
+VB_THRESHOLD = 108 # versionbits activation threshold for regtest
+VB_TOP_BITS = 0x20000000
+VB_UNKNOWN_BIT = 27 # Choose a bit unassigned to any deployment
+
+# TestNode: bare-bones "peer".  Used mostly as a conduit for a test to sending
+# p2p messages to a node, generating the messages in the main testing logic.
+class TestNode(NodeConnCB):
+    def __init__(self):
+        NodeConnCB.__init__(self)
+        self.connection = None
+        self.ping_counter = 1
+        self.last_pong = msg_pong()
+
+    def add_connection(self, conn):
+        self.connection = conn
+
+    def on_inv(self, conn, message):
+        pass
+
+    # Wrapper for the NodeConn's send_message function
+    def send_message(self, message):
+        self.connection.send_message(message)
+
+    def on_pong(self, conn, message):
+        self.last_pong = message
+
+    # Sync up with the node after delivery of a block
+    def sync_with_ping(self, timeout=30):
+        self.connection.send_message(msg_ping(nonce=self.ping_counter))
+        received_pong = False
+        sleep_time = 0.05
+        while not received_pong and timeout > 0:
+            time.sleep(sleep_time)
+            timeout -= sleep_time
+            with mininode_lock:
+                if self.last_pong.nonce == self.ping_counter:
+                    received_pong = True
+        self.ping_counter += 1
+        return received_pong
+
+
+class VersionBitsWarningTest(BitcoinTestFramework):
+    def setup_chain(self):
+        initialize_chain_clean(self.options.tmpdir, 1)
+
+    def setup_network(self):
+        self.nodes = []
+        self.alert_filename = os.path.join(self.options.tmpdir, "alert.txt")
+        # Open and close to create zero-length file
+        with open(self.alert_filename, 'w') as f:
+            pass
+        self.node_options = ["-debug", "-logtimemicros=1", "-alertnotify=echo %s >> \"" + self.alert_filename + "\""]
+        self.nodes.append(start_node(0, self.options.tmpdir, self.node_options))
+
+        import re
+        self.vb_pattern = re.compile("^Warning.*versionbit")
+
+    # Send numblocks blocks via peer with nVersionToUse set.
+    def send_blocks_with_version(self, peer, numblocks, nVersionToUse):
+        tip = self.nodes[0].getbestblockhash()
+        height = self.nodes[0].getblockcount()
+        block_time = self.nodes[0].getblockheader(tip)["time"]+1
+        tip = int(tip, 16)
+
+        for i in xrange(numblocks):
+            block = create_block(tip, create_coinbase(height+1), block_time)
+            block.nVersion = nVersionToUse
+            block.solve()
+            peer.send_message(msg_block(block))
+            block_time += 1
+            height += 1
+            tip = block.sha256
+        peer.sync_with_ping()
+
+    def test_versionbits_in_alert_file(self):
+        with open(self.alert_filename, 'r') as f:
+            alert_text = f.read()
+        assert(self.vb_pattern.match(alert_text))
+
+    def run_test(self):
+        # Setup the p2p connection and start up the network thread.
+        test_node = TestNode()
+
+        connections = []
+        connections.append(NodeConn('127.0.0.1', p2p_port(0), self.nodes[0], test_node))
+        test_node.add_connection(connections[0])
+
+        NetworkThread().start() # Start up network handling in another thread
+
+        # Test logic begins here
+        test_node.wait_for_verack()
+
+        # 1. Have the node mine one period worth of blocks
+        self.nodes[0].generate(VB_PERIOD)
+
+        # 2. Now build one period of blocks on the tip, with < VB_THRESHOLD
+        # blocks signaling some unknown bit.
+        nVersion = VB_TOP_BITS | (1<<VB_UNKNOWN_BIT)
+        self.send_blocks_with_version(test_node, VB_THRESHOLD-1, nVersion)
+
+        # Fill rest of period with regular version blocks
+        self.nodes[0].generate(VB_PERIOD - VB_THRESHOLD + 1)
+        # Check that we're not getting any versionbit-related errors in
+        # getinfo()
+        assert(not self.vb_pattern.match(self.nodes[0].getinfo()["errors"]))
+
+        # 3. Now build one period of blocks with >= VB_THRESHOLD blocks signaling
+        # some unknown bit
+        self.send_blocks_with_version(test_node, VB_THRESHOLD, nVersion)
+        self.nodes[0].generate(VB_PERIOD - VB_THRESHOLD)
+        # Might not get a versionbits-related alert yet, as we should
+        # have gotten a different alert due to more than 51/100 blocks
+        # being of unexpected version.
+        # Check that getinfo() shows some kind of error.
+        assert(len(self.nodes[0].getinfo()["errors"]) != 0)
+
+        # Mine a period worth of expected blocks so the generic block-version warning
+        # is cleared, and restart the node. This should move the versionbit state
+        # to ACTIVE.
+        self.nodes[0].generate(VB_PERIOD)
+        stop_node(self.nodes[0], 0)
+        wait_bitcoinds()
+        # Empty out the alert file
+        with open(self.alert_filename, 'w') as f:
+            pass
+        self.nodes[0] = start_node(0, self.options.tmpdir, ["-debug", "-logtimemicros=1", "-alertnotify=echo %s >> \"" + self.alert_filename + "\""])
+
+        # Connecting one block should be enough to generate an error.
+        self.nodes[0].generate(1)
+        assert(len(self.nodes[0].getinfo()["errors"]) != 0)
+        stop_node(self.nodes[0], 0)
+        wait_bitcoinds()
+        self.test_versionbits_in_alert_file()
+
+        # Test framework expects the node to still be running...
+        self.nodes[0] = start_node(0, self.options.tmpdir, ["-debug", "-logtimemicros=1", "-alertnotify=echo %s >> \"" + self.alert_filename + "\""])
+
+
+if __name__ == '__main__':
+    VersionBitsWarningTest().main()

src/Makefile.am

@@ -152,6 +152,7 @@ BITCOIN_CORE_H = \
   utilmoneystr.h \
   utiltime.h \
   validationinterface.h \
+  versionbits.h \
   wallet/crypter.h \
   wallet/db.h \
   wallet/rpcwallet.h \
@@ -204,6 +205,7 @@ libbitcoin_server_a_SOURCES = \
   txdb.cpp \
   txmempool.cpp \
   validationinterface.cpp \
+  versionbits.cpp \
   $(BITCOIN_CORE_H)
 
 if ENABLE_ZMQ

src/Makefile.test.include

@@ -83,6 +83,7 @@ BITCOIN_TESTS =\
   test/timedata_tests.cpp \
   test/transaction_tests.cpp \
   test/txvalidationcache_tests.cpp \
+  test/versionbits_tests.cpp \
   test/uint256_tests.cpp \
   test/univalue_tests.cpp \
   test/util_tests.cpp

src/chain.h

@@ -14,8 +14,6 @@
 
 #include <vector>
 
-#include <boost/foreach.hpp>
-
 struct CDiskBlockPos
 {
     int nFile;

src/chainparams.cpp

@@ -81,6 +81,11 @@ class CMainParams : public CChainParams {
         consensus.nPowTargetSpacing = 10 * 60;
         consensus.fPowAllowMinDifficultyBlocks = false;
         consensus.fPowNoRetargeting = false;
+        consensus.nRuleChangeActivationThreshold = 1916; // 95% of 2016
+        consensus.nMinerConfirmationWindow = 2016; // nPowTargetTimespan / nPowTargetSpacing
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 1199145601; // January 1, 2008
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = 1230767999; // December 31, 2008
         /** 
          * The message start string is designed to be unlikely to occur in normal data.
          * The characters are rarely used upper ASCII, not valid as UTF-8, and produce
@@ -162,6 +167,11 @@ class CTestNetParams : public CChainParams {
         consensus.nPowTargetSpacing = 10 * 60;
         consensus.fPowAllowMinDifficultyBlocks = true;
         consensus.fPowNoRetargeting = false;
+        consensus.nRuleChangeActivationThreshold = 1512; // 75% for testchains
+        consensus.nMinerConfirmationWindow = 2016; // nPowTargetTimespan / nPowTargetSpacing
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 1199145601; // January 1, 2008
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = 1230767999; // December 31, 2008
         pchMessageStart[0] = 0x0b;
         pchMessageStart[1] = 0x11;
         pchMessageStart[2] = 0x09;
@@ -225,6 +235,11 @@ class CRegTestParams : public CChainParams {
         consensus.nPowTargetSpacing = 10 * 60;
         consensus.fPowAllowMinDifficultyBlocks = true;
         consensus.fPowNoRetargeting = true;
+        consensus.nRuleChangeActivationThreshold = 108; // 75% for testchains
+        consensus.nMinerConfirmationWindow = 144; // Faster than normal for regtest (144 instead of 2016)
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 0;
+        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = 999999999999ULL;
 
         pchMessageStart[0] = 0xfa;
         pchMessageStart[1] = 0xbf;

src/consensus/params.h

@@ -7,8 +7,29 @@
 #define BITCOIN_CONSENSUS_PARAMS_H
 
 #include "uint256.h"
+#include <map>
+#include <string>
 
 namespace Consensus {
+
+enum DeploymentPos
+{
+    DEPLOYMENT_TESTDUMMY,
+    MAX_VERSION_BITS_DEPLOYMENTS
+};
+
+/**
+ * Struct for each individual consensus rule change using BIP9.
+ */
+struct BIP9Deployment {
+    /** Bit position to select the particular bit in nVersion. */
+    int bit;
+    /** Start MedianTime for version bits miner confirmation. Can be a date in the past */
+    int64_t nStartTime;
+    /** Timeout/expiry MedianTime for the deployment attempt. */
+    int64_t nTimeout;
+};
+
 /**
  * Parameters that influence chain consensus.
  */
@@ -22,6 +43,14 @@ struct Params {
     /** Block height and hash at which BIP34 becomes active */
     int BIP34Height;
     uint256 BIP34Hash;
+    /**
+     * Minimum blocks including miner confirmation of the total of 2016 blocks in a retargetting period,
+     * (nPowTargetTimespan / nPowTargetSpacing) which is also used for BIP9 deployments.
+     * Examples: 1916 for 95%, 1512 for testchains.
+     */
+    uint32_t nRuleChangeActivationThreshold;
+    uint32_t nMinerConfirmationWindow;
+    BIP9Deployment vDeployments[MAX_VERSION_BITS_DEPLOYMENTS];
     /** Proof of work parameters */
     uint256 powLimit;
     bool fPowAllowMinDifficultyBlocks;

src/init.cpp

@@ -466,7 +466,7 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-blockmaxsize=<n>", strprintf(_("Set maximum block size in bytes (default: %d)"), DEFAULT_BLOCK_MAX_SIZE));
     strUsage += HelpMessageOpt("-blockprioritysize=<n>", strprintf(_("Set maximum size of high-priority/low-fee transactions in bytes (default: %d)"), DEFAULT_BLOCK_PRIORITY_SIZE));
     if (showDebug)
-        strUsage += HelpMessageOpt("-blockversion=<n>", strprintf("Override block version to test forking scenarios (default: %d)", (int)CBlock::CURRENT_VERSION));
+        strUsage += HelpMessageOpt("-blockversion=<n>", "Override block version to test forking scenarios");
 
     strUsage += HelpMessageGroup(_("RPC server options:"));
     strUsage += HelpMessageOpt("-server", _("Accept command line and JSON-RPC commands"));