#!/usr/bin/env python3 # Copyright (c) 2015-2017 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.test_framework import BitcoinTestFramework from test_framework.util import * from test_framework.mininode import * from test_framework.blocktools import create_coinbase, create_block from test_framework.script import CScript, OP_1NEGATE, OP_CHECKLOCKTIMEVERIFY, OP_DROP, CScriptNum 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 def create_transaction(node, coinbase, to_address, amount): from_txid = node.getblock(coinbase)['tx'][0] inputs = [{ "txid" : from_txid, "vout" : 0}] outputs = { to_address : amount } rawtx = node.createrawtransaction(inputs, outputs) signresult = node.signrawtransactionwithwallet(rawtx) tx = CTransaction() tx.deserialize(BytesIO(hex_str_to_bytes(signresult['hex']))) return tx class BIP65Test(BitcoinTestFramework): def set_test_params(self): self.num_nodes = 1 self.extra_args = [['-whitelist=127.0.0.1']] self.setup_clean_chain = True def run_test(self): self.nodes[0].add_p2p_connection(P2PInterface()) network_thread_start() # wait_for_verack ensures that the P2P connection is fully up. self.nodes[0].p2p.wait_for_verack() self.log.info("Mining %d blocks", CLTV_HEIGHT - 2) self.coinbase_blocks = 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_blocks[0], self.nodeaddress, 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() self.nodes[0].p2p.send_and_ping(msg_block(block)) assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip) wait_until(lambda: "reject" in self.nodes[0].p2p.last_message.keys(), lock=mininode_lock) with mininode_lock: assert_equal(self.nodes[0].p2p.last_message["reject"].code, REJECT_OBSOLETE) assert_equal(self.nodes[0].p2p.last_message["reject"].reason, b'bad-version(0x00000003)') assert_equal(self.nodes[0].p2p.last_message["reject"].data, block.sha256) del self.nodes[0].p2p.last_message["reject"] 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_blocks[1], self.nodeaddress, 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() self.nodes[0].p2p.send_and_ping(msg_block(block)) assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip) wait_until(lambda: "reject" in self.nodes[0].p2p.last_message.keys(), lock=mininode_lock) with mininode_lock: assert self.nodes[0].p2p.last_message["reject"].code in [REJECT_INVALID, REJECT_NONSTANDARD] assert_equal(self.nodes[0].p2p.last_message["reject"].data, block.sha256) if self.nodes[0].p2p.last_message["reject"].code == REJECT_INVALID: # Generic rejection when a block is invalid assert_equal(self.nodes[0].p2p.last_message["reject"].reason, b'block-validation-failed') else: assert b'Negative locktime' in self.nodes[0].p2p.last_message["reject"].reason 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()