#!/usr/bin/env python3 # Copyright (c) 2015-2018 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 BIP65 (CHECKLOCKTIMEVERIFY). Test that the CHECKLOCKTIMEVERIFY soft-fork activates at (regtest) block height 1351. """ from test_framework.blocktools import create_coinbase, create_block, create_transaction from test_framework.messages import CTransaction, msg_block, ToHex from test_framework.mininode import P2PInterface from test_framework.script import CScript, OP_1NEGATE, OP_CHECKLOCKTIMEVERIFY, OP_DROP, CScriptNum from test_framework.test_framework import BitcoinTestFramework from test_framework.util import ( assert_equal, bytes_to_hex_str, hex_str_to_bytes, ) from io import BytesIO CLTV_HEIGHT = 1351 # Reject codes that we might receive in this test REJECT_INVALID = 16 REJECT_OBSOLETE = 17 REJECT_NONSTANDARD = 64 def cltv_invalidate(tx): '''Modify the signature in vin 0 of the tx to fail CLTV Prepends -1 CLTV DROP in the scriptSig itself. TODO: test more ways that transactions using CLTV could be invalid (eg locktime requirements fail, sequence time requirements fail, etc). ''' tx.vin[0].scriptSig = CScript([OP_1NEGATE, OP_CHECKLOCKTIMEVERIFY, OP_DROP] + list(CScript(tx.vin[0].scriptSig))) def cltv_validate(node, tx, height): '''Modify the signature in vin 0 of the tx to pass CLTV Prepends CLTV DROP in the scriptSig, and sets the locktime to height''' tx.vin[0].nSequence = 0 tx.nLockTime = height # Need to re-sign, since nSequence and nLockTime changed signed_result = node.signrawtransactionwithwallet(ToHex(tx)) new_tx = CTransaction() new_tx.deserialize(BytesIO(hex_str_to_bytes(signed_result['hex']))) new_tx.vin[0].scriptSig = CScript([CScriptNum(height), OP_CHECKLOCKTIMEVERIFY, OP_DROP] + list(CScript(new_tx.vin[0].scriptSig))) return new_tx class BIP65Test(BitcoinTestFramework): def set_test_params(self): self.num_nodes = 1 self.extra_args = [['-whitelist=127.0.0.1', '-par=1']] # Use only one script thread to get the exact reject reason for testing self.setup_clean_chain = True def skip_test_if_missing_module(self): self.skip_if_no_wallet() def run_test(self): self.nodes[0].add_p2p_connection(P2PInterface()) self.log.info("Mining %d blocks", CLTV_HEIGHT - 2) self.coinbase_txids = [self.nodes[0].getblock(b)['tx'][0] for b in self.nodes[0].generate(CLTV_HEIGHT - 2)] self.nodeaddress = self.nodes[0].getnewaddress() self.log.info("Test that an invalid-according-to-CLTV transaction can still appear in a block") spendtx = create_transaction(self.nodes[0], self.coinbase_txids[0], self.nodeaddress, amount=1.0) cltv_invalidate(spendtx) spendtx.rehash() tip = self.nodes[0].getbestblockhash() block_time = self.nodes[0].getblockheader(tip)['mediantime'] + 1 block = create_block(int(tip, 16), create_coinbase(CLTV_HEIGHT - 1), block_time) block.nVersion = 3 block.vtx.append(spendtx) block.hashMerkleRoot = block.calc_merkle_root() block.solve() self.nodes[0].p2p.send_and_ping(msg_block(block)) assert_equal(self.nodes[0].getbestblockhash(), block.hash) self.log.info("Test that blocks must now be at least version 4") tip = block.sha256 block_time += 1 block = create_block(tip, create_coinbase(CLTV_HEIGHT), block_time) block.nVersion = 3 block.solve() with self.nodes[0].assert_debug_log(expected_msgs=['{}, bad-version(0x00000003)'.format(block.hash)]): self.nodes[0].p2p.send_and_ping(msg_block(block)) assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip) self.nodes[0].p2p.sync_with_ping() self.log.info("Test that invalid-according-to-cltv transactions cannot appear in a block") block.nVersion = 4 spendtx = create_transaction(self.nodes[0], self.coinbase_txids[1], self.nodeaddress, amount=1.0) cltv_invalidate(spendtx) spendtx.rehash() # First we show that this tx is valid except for CLTV by getting it # rejected from the mempool for exactly that reason. assert_equal( [{'txid': spendtx.hash, 'allowed': False, 'reject-reason': '64: non-mandatory-script-verify-flag (Negative locktime)'}], self.nodes[0].testmempoolaccept(rawtxs=[bytes_to_hex_str(spendtx.serialize())], allowhighfees=True) ) # Now we verify that a block with this transaction is also invalid. block.vtx.append(spendtx) block.hashMerkleRoot = block.calc_merkle_root() block.solve() with self.nodes[0].assert_debug_log(expected_msgs=['CheckInputs on {} failed with non-mandatory-script-verify-flag (Negative locktime)'.format(block.vtx[-1].hash)]): self.nodes[0].p2p.send_and_ping(msg_block(block)) assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip) self.nodes[0].p2p.sync_with_ping() self.log.info("Test that a version 4 block with a valid-according-to-CLTV transaction is accepted") spendtx = cltv_validate(self.nodes[0], spendtx, CLTV_HEIGHT - 1) spendtx.rehash() block.vtx.pop(1) block.vtx.append(spendtx) block.hashMerkleRoot = block.calc_merkle_root() block.solve() self.nodes[0].p2p.send_and_ping(msg_block(block)) assert_equal(int(self.nodes[0].getbestblockhash(), 16), block.sha256) if __name__ == '__main__': BIP65Test().main()