#!/usr/bin/env python # -*- coding: utf-8 -*- # Copyright (c) 2023 tecnovert # Distributed under the MIT software license, see the accompanying # file LICENSE or http://www.opensource.org/licenses/mit-license.php. import random import hashlib from io import BytesIO from coincurve.keys import ( PublicKey, PrivateKey, ) from .btc import BTCInterface, find_vout_for_address_from_txobj, findOutput from basicswap.rpc import make_rpc_func from basicswap.chainparams import Coins from basicswap.interface.contrib.nav_test_framework.mininode import ( CTxIn, CTxOut, CBlock, COutPoint, CTransaction, CTxInWitness, FromHex, uint256_from_str, ) from basicswap.util.crypto import hash160 from basicswap.util.address import ( decodeWif, pubkeyToAddress, encodeAddress, ) from basicswap.util import ( i2b, i2h, ensure, ) from basicswap.basicswap_util import ( getVoutByScriptPubKey, ) from basicswap.interface.contrib.nav_test_framework.script import ( CScript, OP_0, OP_EQUAL, OP_DUP, OP_HASH160, OP_EQUALVERIFY, OP_CHECKSIG, SIGHASH_ALL, SegwitVersion1SignatureHash, ) from mnemonic import Mnemonic class NAVInterface(BTCInterface): @staticmethod def coin_type(): return Coins.NAV @staticmethod def txVersion() -> int: return 3 @staticmethod def txoType(): return CTxOut def __init__(self, coin_settings, network, swap_client=None): super(NAVInterface, self).__init__(coin_settings, network, swap_client) # No multiwallet support self.rpc_wallet = make_rpc_func(self._rpcport, self._rpcauth, host=self._rpc_host) def checkWallets(self) -> int: return 1 def use_p2shp2wsh(self) -> bool: # p2sh-p2wsh return True def seedToMnemonic(self, key): return Mnemonic('english').to_mnemonic(key) def initialiseWallet(self, key): # load with -importmnemonic= parameter pass def getWalletSeedID(self): return self.rpc('getwalletinfo')['hdmasterkeyid'] def withdrawCoin(self, value, addr_to: str, subfee: bool): strdzeel = '' params = [addr_to, value, '', '', strdzeel, subfee] return self.rpc('sendtoaddress', params) def getSpendableBalance(self) -> int: return self.make_int(self.rpc('getwalletinfo')['balance']) def signTxWithWallet(self, tx: bytes) -> bytes: rv = self.rpc('signrawtransaction', [tx.hex()]) return bytes.fromhex(rv['hex']) def checkExpectedSeed(self, key_hash: str): try: rv = self.rpc('dumpmnemonic') entropy = Mnemonic('english').to_entropy(rv.split(' ')) entropy_hash = self.getAddressHashFromKey(entropy)[::-1].hex() self._have_checked_seed = True return entropy_hash == key_hash except Exception as e: self._log.warning('checkExpectedSeed failed: {}'.format(str(e))) return False def getScriptForP2PKH(self, pkh: bytes) -> bytearray: # Return P2PKH return CScript([OP_DUP, OP_HASH160, pkh, OP_EQUALVERIFY, OP_CHECKSIG]) def getScriptForPubkeyHash(self, pkh: bytes) -> bytearray: # Return P2SH-p2wpkh script = CScript([OP_0, pkh]) script_hash = hash160(script) assert len(script_hash) == 20 return CScript([OP_HASH160, script_hash, OP_EQUAL]) def getInputScriptForPubkeyHash(self, pkh: bytes) -> bytearray: script = CScript([OP_0, pkh]) return bytes((len(script),)) + script def encodeSegwitAddress(self, pkh: bytes) -> str: # P2SH-p2wpkh script = CScript([OP_0, pkh]) script_hash = hash160(script) assert len(script_hash) == 20 return encodeAddress(bytes((self.chainparams_network()['script_address'],)) + script_hash) def encodeSegwitAddressScript(self, script: bytes) -> str: if len(script) == 23 and script[0] == OP_HASH160 and script[1] == 20 and script[22] == OP_EQUAL: script_hash = script[2:22] return encodeAddress(bytes((self.chainparams_network()['script_address'],)) + script_hash) raise ValueError('Unknown Script') def loadTx(self, tx_bytes: bytes) -> CTransaction: # Load tx from bytes to internal representation tx = CTransaction() tx.deserialize(BytesIO(tx_bytes)) return tx def signTx(self, key_bytes: bytes, tx_bytes: bytes, input_n: int, prevout_script, prevout_value: int): tx = self.loadTx(tx_bytes) sig_hash = SegwitVersion1SignatureHash(prevout_script, tx, input_n, SIGHASH_ALL, prevout_value) eck = PrivateKey(key_bytes) return eck.sign(sig_hash, hasher=None) + bytes((SIGHASH_ALL,)) def setTxSignature(self, tx_bytes: bytes, stack) -> bytes: tx = self.loadTx(tx_bytes) tx.wit.vtxinwit.clear() tx.wit.vtxinwit.append(CTxInWitness()) tx.wit.vtxinwit[0].scriptWitness.stack = stack return tx.serialize_with_witness() def getProofOfFunds(self, amount_for, extra_commit_bytes): # TODO: Lock unspent and use same output/s to fund bid unspents_by_addr = dict() unspents = self.rpc('listunspent') for u in unspents: if u['spendable'] is not True: continue if u['address'] not in unspents_by_addr: unspents_by_addr[u['address']] = {'total': 0, 'utxos': []} utxo_amount: int = self.make_int(u['amount'], r=1) unspents_by_addr[u['address']]['total'] += utxo_amount unspents_by_addr[u['address']]['utxos'].append((utxo_amount, u['txid'], u['vout'])) max_utxos: int = 4 viable_addrs = [] for addr, data in unspents_by_addr.items(): if data['total'] >= amount_for: # Sort from largest to smallest amount sorted_utxos = sorted(data['utxos'], key=lambda x: x[0]) # Max outputs required to reach amount_for utxos_req: int = 0 sum_value: int = 0 for utxo in sorted_utxos: sum_value += utxo[0] utxos_req += 1 if sum_value >= amount_for: break if utxos_req <= max_utxos: viable_addrs.append(addr) continue ensure(len(viable_addrs) > 0, 'Could not find address with enough funds for proof') sign_for_addr: str = random.choice(viable_addrs) self._log.debug('sign_for_addr %s', sign_for_addr) prove_utxos = [] sorted_utxos = sorted(unspents_by_addr[sign_for_addr]['utxos'], key=lambda x: x[0]) hasher = hashlib.sha256() sum_value: int = 0 for utxo in sorted_utxos: sum_value += utxo[0] outpoint = (bytes.fromhex(utxo[1]), utxo[2]) prove_utxos.append(outpoint) hasher.update(outpoint[0]) hasher.update(outpoint[1].to_bytes(2, 'big')) if sum_value >= amount_for: break utxos_hash = hasher.digest() self._log.debug('sign_for_addr %s', sign_for_addr) if self.using_segwit(): # TODO: Use isSegwitAddress when scantxoutset can use combo # 'Address does not refer to key' for non p2pkh addr_info = self.rpc('validateaddress', [addr, ]) if 'isscript' in addr_info and addr_info['isscript'] and 'hex' in addr_info: pkh = bytes.fromhex(addr_info['hex'])[2:] sign_for_addr = self.pkh_to_address(pkh) self._log.debug('sign_for_addr converted %s', sign_for_addr) signature = self.rpc('signmessage', [sign_for_addr, sign_for_addr + '_swap_proof_' + utxos_hash.hex() + extra_commit_bytes.hex()]) return (sign_for_addr, signature, prove_utxos) def verifyProofOfFunds(self, address, signature, utxos, extra_commit_bytes): hasher = hashlib.sha256() sum_value: int = 0 for outpoint in utxos: hasher.update(outpoint[0]) hasher.update(outpoint[1].to_bytes(2, 'big')) utxos_hash = hasher.digest() passed = self.verifyMessage(address, address + '_swap_proof_' + utxos_hash.hex() + extra_commit_bytes.hex(), signature) ensure(passed is True, 'Proof of funds signature invalid') if self.using_segwit(): address = self.encodeSegwitAddress(self.decodeAddress(address)[1:]) sum_value: int = 0 for outpoint in utxos: txout = self.rpc('gettxout', [outpoint[0].hex(), outpoint[1]]) sum_value += self.make_int(txout['value']) return sum_value def createRawFundedTransaction(self, addr_to: str, amount: int, sub_fee: bool = False, lock_unspents: bool = True) -> str: txn = self.rpc('createrawtransaction', [[], {addr_to: self.format_amount(amount)}]) fee_rate, fee_src = self.get_fee_rate(self._conf_target) self._log.debug(f'Fee rate: {fee_rate}, source: {fee_src}, block target: {self._conf_target}') if sub_fee: raise ValueError('Navcoin fundrawtransaction is missing the subtractFeeFromOutputs parameter') # options['subtractFeeFromOutputs'] = [0,] fee_rate = self.make_int(fee_rate, r=1) return self.fundTx(txn, fee_rate, lock_unspents).hex() def isAddressMine(self, address: str, or_watch_only: bool = False) -> bool: addr_info = self.rpc('validateaddress', [address]) if not or_watch_only: return addr_info['ismine'] return addr_info['ismine'] or addr_info['iswatchonly'] def createRawSignedTransaction(self, addr_to, amount) -> str: txn_funded = self.createRawFundedTransaction(addr_to, amount) return self.rpc('signrawtransaction', [txn_funded])['hex'] def getBlockchainInfo(self): rv = self.rpc('getblockchaininfo') synced = round(rv['verificationprogress'], 3) if synced >= 0.997: rv['verificationprogress'] = 1.0 return rv def encodeScriptDest(self, script_dest: bytes) -> str: script_hash = script_dest[2:-1] # Extract hash from script return self.sh_to_address(script_hash) def encode_p2wsh(self, script: bytes) -> str: return pubkeyToAddress(self.chainparams_network()['script_address'], script) def find_prevout_info(self, txn_hex: str, txn_script: bytes): txjs = self.rpc('decoderawtransaction', [txn_hex]) n = getVoutByScriptPubKey(txjs, self.getScriptDest(txn_script).hex()) return { 'txid': txjs['txid'], 'vout': n, 'scriptPubKey': txjs['vout'][n]['scriptPubKey']['hex'], 'redeemScript': txn_script.hex(), 'amount': txjs['vout'][n]['value'] } def getNewAddress(self, use_segwit: bool, label: str = 'swap_receive') -> str: address: str = self.rpc('getnewaddress', [label,]) if use_segwit: return self.rpc('addwitnessaddress', [address,]) return address def createRedeemTxn(self, prevout, output_addr: str, output_value: int, txn_script: bytes) -> str: tx = CTransaction() tx.nVersion = self.txVersion() prev_txid = uint256_from_str(bytes.fromhex(prevout['txid'])[::-1]) tx.vin.append(CTxIn(COutPoint(prev_txid, prevout['vout']), scriptSig=self.getScriptScriptSig(txn_script))) pkh = self.decodeAddress(output_addr) script = self.getScriptForPubkeyHash(pkh) tx.vout.append(self.txoType()(output_value, script)) tx.rehash() return tx.serialize().hex() def createRefundTxn(self, prevout, output_addr: str, output_value: int, locktime: int, sequence: int, txn_script: bytes) -> str: tx = CTransaction() tx.nVersion = self.txVersion() tx.nLockTime = locktime prev_txid = uint256_from_str(bytes.fromhex(prevout['txid'])[::-1]) tx.vin.append(CTxIn(COutPoint(prev_txid, prevout['vout']), nSequence=sequence, scriptSig=self.getScriptScriptSig(txn_script))) pkh = self.decodeAddress(output_addr) script = self.getScriptForPubkeyHash(pkh) tx.vout.append(self.txoType()(output_value, script)) tx.rehash() return tx.serialize().hex() def getTxSignature(self, tx_hex: str, prevout_data, key_wif: str) -> str: key = decodeWif(key_wif) redeem_script = bytes.fromhex(prevout_data['redeemScript']) sig = self.signTx(key, bytes.fromhex(tx_hex), 0, redeem_script, self.make_int(prevout_data['amount'])) return sig.hex() def verifyTxSig(self, tx_bytes: bytes, sig: bytes, K: bytes, input_n: int, prevout_script: bytes, prevout_value: int) -> bool: tx = self.loadTx(tx_bytes) sig_hash = SegwitVersion1SignatureHash(prevout_script, tx, input_n, SIGHASH_ALL, prevout_value) pubkey = PublicKey(K) return pubkey.verify(sig[: -1], sig_hash, hasher=None) # Pop the hashtype byte def verifyRawTransaction(self, tx_hex: str, prevouts): # Only checks signature # verifyrawtransaction self._log.warning('NAV verifyRawTransaction only checks signature') inputs_valid: bool = False validscripts: int = 0 tx_bytes = bytes.fromhex(tx_hex) tx = self.loadTx(bytes.fromhex(tx_hex)) signature = tx.wit.vtxinwit[0].scriptWitness.stack[0] pubkey = tx.wit.vtxinwit[0].scriptWitness.stack[1] input_n: int = 0 prevout_data = prevouts[input_n] redeem_script = bytes.fromhex(prevout_data['redeemScript']) prevout_value = self.make_int(prevout_data['amount']) if self.verifyTxSig(tx_bytes, signature, pubkey, input_n, redeem_script, prevout_value): validscripts += 1 # TODO: validate inputs inputs_valid = True return { 'inputs_valid': inputs_valid, 'validscripts': validscripts, } def getHTLCSpendTxVSize(self, redeem: bool = True) -> int: tx_vsize = 5 # Add a few bytes, sequence in script takes variable amount of bytes tx_vsize += 184 if redeem else 187 return tx_vsize def getTxid(self, tx) -> bytes: if isinstance(tx, str): tx = bytes.fromhex(tx) if isinstance(tx, bytes): tx = self.loadTx(tx) tx.rehash() return i2b(tx.sha256) def rescanBlockchainForAddress(self, height_start: int, addr_find: str): # Very ugly workaround for missing `rescanblockchain` rpc command chain_blocks: int = self.getChainHeight() current_height: int = chain_blocks block_hash = self.rpc('getblockhash', [current_height]) script_hash: bytes = self.decodeAddress(addr_find) find_scriptPubKey = self.getDestForScriptHash(script_hash) while current_height > height_start: block_hash = self.rpc('getblockhash', [current_height]) block = self.rpc('getblock', [block_hash, False]) decoded_block = CBlock() decoded_block = FromHex(decoded_block, block) for tx in decoded_block.vtx: for txo in tx.vout: if txo.scriptPubKey == find_scriptPubKey: tx.rehash() txid = i2b(tx.sha256) self._log.info('Found output to addr: {} in tx {} in block {}'.format(addr_find, txid.hex(), block_hash)) self._log.info('rescanblockchain hack invalidateblock {}'.format(block_hash)) self.rpc('invalidateblock', [block_hash]) self.rpc('reconsiderblock', [block_hash]) return current_height -= 1 def getLockTxHeight(self, txid, dest_address, bid_amount, rescan_from, find_index: bool = False): # Add watchonly address and rescan if required if not self.isAddressMine(dest_address, or_watch_only=True): self.importWatchOnlyAddress(dest_address, 'bid') self._log.info('Imported watch-only addr: {}'.format(dest_address)) self._log.info('Rescanning {} chain from height: {}'.format(self.coin_name(), rescan_from)) self.rescanBlockchainForAddress(rescan_from, dest_address) return_txid = True if txid is None else False if txid is None: txns = self.rpc('listunspent', [0, 9999999, [dest_address, ]]) for tx in txns: if self.make_int(tx['amount']) == bid_amount: txid = bytes.fromhex(tx['txid']) break if txid is None: return None try: tx = self.rpc('gettransaction', [txid.hex()]) block_height = 0 if 'blockhash' in tx: block_header = self.rpc('getblockheader', [tx['blockhash']]) block_height = block_header['height'] rv = { 'depth': 0 if 'confirmations' not in tx else tx['confirmations'], 'height': block_height} except Exception as e: self._log.debug('getLockTxHeight gettransaction failed: %s, %s', txid.hex(), str(e)) return None if find_index: tx_obj = self.rpc('decoderawtransaction', [tx['hex']]) rv['index'] = find_vout_for_address_from_txobj(tx_obj, dest_address) if return_txid: rv['txid'] = txid.hex() return rv def getBlockWithTxns(self, block_hash): # TODO: Bypass decoderawtransaction and getblockheader block = self.rpc('getblock', [block_hash, False]) block_header = self.rpc('getblockheader', [block_hash]) decoded_block = CBlock() decoded_block = FromHex(decoded_block, block) tx_rv = [] for tx in decoded_block.vtx: tx_hex = tx.serialize_with_witness().hex() tx_dec = self.rpc('decoderawtransaction', [tx_hex]) if 'hex' not in tx_dec: tx_dec['hex'] = tx_hex tx_rv.append(tx_dec) block_rv = { 'hash': block_hash, 'tx': tx_rv, 'confirmations': block_header['confirmations'], 'height': block_header['height'], 'version': block_header['version'], 'merkleroot': block_header['merkleroot'], } return block_rv def getScriptScriptSig(self, script: bytes) -> bytearray: return self.getP2SHP2WSHScriptSig(script) def getScriptDest(self, script): return self.getP2SHP2WSHDest(script) def getDestForScriptHash(self, script_hash): assert len(script_hash) == 20 return CScript([OP_HASH160, script_hash, OP_EQUAL]) def pubkey_to_segwit_address(self, pk: bytes) -> str: pkh = hash160(pk) script_out = self.getScriptForPubkeyHash(pkh) return self.encodeSegwitAddressScript(script_out) def createBLockTx(self, Kbs: bytes, output_amount: int, vkbv=None) -> bytes: tx = CTransaction() tx.nVersion = self.txVersion() script_pk = self.getPkDest(Kbs) tx.vout.append(self.txoType()(output_amount, script_pk)) return tx.serialize() def spendBLockTx(self, chain_b_lock_txid: bytes, address_to: str, kbv: bytes, kbs: bytes, cb_swap_value: int, b_fee: int, restore_height: int) -> bytes: self._log.info('spendBLockTx %s:\n', chain_b_lock_txid.hex()) wtx = self.rpc('gettransaction', [chain_b_lock_txid.hex(), ]) lock_tx = self.loadTx(bytes.fromhex(wtx['hex'])) Kbs = self.getPubkey(kbs) script_pk = self.getPkDest(Kbs) locked_n = findOutput(lock_tx, script_pk) ensure(locked_n is not None, 'Output not found in tx') pkh_to = self.decodeAddress(address_to) tx = CTransaction() tx.nVersion = self.txVersion() chain_b_lock_txid_int = uint256_from_str(chain_b_lock_txid[::-1]) script_sig = self.getInputScriptForPubkeyHash(self.getPubkeyHash(Kbs)) tx.vin.append(CTxIn(COutPoint(chain_b_lock_txid_int, locked_n), nSequence=0, scriptSig=script_sig)) tx.vout.append(self.txoType()(cb_swap_value, self.getScriptForPubkeyHash(pkh_to))) pay_fee = self.getBLockSpendTxFee(tx, b_fee) tx.vout[0].nValue = cb_swap_value - pay_fee b_lock_spend_tx = tx.serialize() b_lock_spend_tx = self.signTxWithKey(b_lock_spend_tx, kbs, cb_swap_value) return bytes.fromhex(self.publishTx(b_lock_spend_tx)) def signTxWithKey(self, tx: bytes, key: bytes, prev_amount: int) -> bytes: Key = self.getPubkey(key) pkh = self.getPubkeyHash(Key) script = self.getScriptForP2PKH(pkh) sig = self.signTx(key, tx, 0, script, prev_amount) stack = [ sig, Key, ] return self.setTxSignature(tx, stack) def findTxnByHash(self, txid_hex: str): # Only works for wallet txns try: rv = self.rpc('gettransaction', [txid_hex]) except Exception as ex: self._log.debug('findTxnByHash getrawtransaction failed: {}'.format(txid_hex)) return None if 'confirmations' in rv and rv['confirmations'] >= self.blocks_confirmed: block_height = self.getBlockHeader(rv['blockhash'])['height'] return {'txid': txid_hex, 'amount': 0, 'height': block_height} return None def createSCLockTx(self, value: int, script: bytearray, vkbv: bytes = None) -> bytes: tx = CTransaction() tx.nVersion = self.txVersion() tx.vout.append(self.txoType()(value, self.getScriptDest(script))) return tx.serialize() def fundTx(self, tx_hex: str, feerate: int, lock_unspents: bool = True): feerate_str = self.format_amount(feerate) # TODO: unlock unspents if bid cancelled options = { 'lockUnspents': lock_unspents, 'feeRate': feerate_str, } rv = self.rpc('fundrawtransaction', [tx_hex, options]) # Sign transaction then strip witness data to fill scriptsig rv = self.rpc('signrawtransaction', [rv['hex']]) tx_signed = self.loadTx(bytes.fromhex(rv['hex'])) if len(tx_signed.vin) != len(tx_signed.wit.vtxinwit): raise ValueError('txn has non segwit input') for witness_data in tx_signed.wit.vtxinwit: if len(witness_data.scriptWitness.stack) < 2: raise ValueError('txn has non segwit input') return tx_signed.serialize_without_witness() def fundSCLockTx(self, tx_bytes: bytes, feerate, vkbv=None) -> bytes: tx_funded = self.fundTx(tx_bytes.hex(), feerate) return tx_funded def createSCLockRefundTx(self, tx_lock_bytes, script_lock, Kal, Kaf, lock1_value, csv_val, tx_fee_rate, vkbv=None): tx_lock = CTransaction() tx_lock = self.loadTx(tx_lock_bytes) output_script = self.getScriptDest(script_lock) locked_n = findOutput(tx_lock, output_script) ensure(locked_n is not None, 'Output not found in tx') locked_coin = tx_lock.vout[locked_n].nValue tx_lock.rehash() tx_lock_id_int = tx_lock.sha256 refund_script = self.genScriptLockRefundTxScript(Kal, Kaf, csv_val) tx = CTransaction() tx.nVersion = self.txVersion() tx.vin.append(CTxIn(COutPoint(tx_lock_id_int, locked_n), nSequence=lock1_value, scriptSig=self.getScriptScriptSig(script_lock))) tx.vout.append(self.txoType()(locked_coin, self.getScriptDest(refund_script))) dummy_witness_stack = self.getScriptLockTxDummyWitness(script_lock) witness_bytes = self.getWitnessStackSerialisedLength(dummy_witness_stack) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) pay_fee = round(tx_fee_rate * vsize / 1000) tx.vout[0].nValue = locked_coin - pay_fee tx.rehash() self._log.info('createSCLockRefundTx %s:\n fee_rate, vsize, fee: %ld, %ld, %ld.', i2h(tx.sha256), tx_fee_rate, vsize, pay_fee) return tx.serialize(), refund_script, tx.vout[0].nValue def createSCLockRefundSpendTx(self, tx_lock_refund_bytes, script_lock_refund, pkh_refund_to, tx_fee_rate, vkbv=None): # Returns the coinA locked coin to the leader # The follower will sign the multisig path with a signature encumbered by the leader's coinB spend pubkey # If the leader publishes the decrypted signature the leader's coinB spend privatekey will be revealed to the follower tx_lock_refund = self.loadTx(tx_lock_refund_bytes) output_script = self.getScriptDest(script_lock_refund) locked_n = findOutput(tx_lock_refund, output_script) ensure(locked_n is not None, 'Output not found in tx') locked_coin = tx_lock_refund.vout[locked_n].nValue tx_lock_refund.rehash() tx_lock_refund_hash_int = tx_lock_refund.sha256 tx = CTransaction() tx.nVersion = self.txVersion() tx.vin.append(CTxIn(COutPoint(tx_lock_refund_hash_int, locked_n), nSequence=0, scriptSig=self.getScriptScriptSig(script_lock_refund))) tx.vout.append(self.txoType()(locked_coin, self.getScriptForPubkeyHash(pkh_refund_to))) dummy_witness_stack = self.getScriptLockRefundSpendTxDummyWitness(script_lock_refund) witness_bytes = self.getWitnessStackSerialisedLength(dummy_witness_stack) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) pay_fee = round(tx_fee_rate * vsize / 1000) tx.vout[0].nValue = locked_coin - pay_fee tx.rehash() self._log.info('createSCLockRefundSpendTx %s:\n fee_rate, vsize, fee: %ld, %ld, %ld.', i2h(tx.sha256), tx_fee_rate, vsize, pay_fee) return tx.serialize() def createSCLockRefundSpendToFTx(self, tx_lock_refund_bytes, script_lock_refund, pkh_dest, tx_fee_rate, vkbv=None): # lock refund swipe tx # Sends the coinA locked coin to the follower tx_lock_refund = self.loadTx(tx_lock_refund_bytes) output_script = self.getScriptDest(script_lock_refund) locked_n = findOutput(tx_lock_refund, output_script) ensure(locked_n is not None, 'Output not found in tx') locked_coin = tx_lock_refund.vout[locked_n].nValue A, B, lock2_value, C = self.extractScriptLockRefundScriptValues(script_lock_refund) tx_lock_refund.rehash() tx_lock_refund_hash_int = tx_lock_refund.sha256 tx = CTransaction() tx.nVersion = self.txVersion() tx.vin.append(CTxIn(COutPoint(tx_lock_refund_hash_int, locked_n), nSequence=lock2_value, scriptSig=self.getScriptScriptSig(script_lock_refund))) tx.vout.append(self.txoType()(locked_coin, self.getScriptForPubkeyHash(pkh_dest))) dummy_witness_stack = self.getScriptLockRefundSwipeTxDummyWitness(script_lock_refund) witness_bytes = self.getWitnessStackSerialisedLength(dummy_witness_stack) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) pay_fee = round(tx_fee_rate * vsize / 1000) tx.vout[0].nValue = locked_coin - pay_fee tx.rehash() self._log.info('createSCLockRefundSpendToFTx %s:\n fee_rate, vsize, fee: %ld, %ld, %ld.', i2h(tx.sha256), tx_fee_rate, vsize, pay_fee) return tx.serialize() def createSCLockSpendTx(self, tx_lock_bytes, script_lock, pkh_dest, tx_fee_rate, vkbv=None, fee_info={}): tx_lock = self.loadTx(tx_lock_bytes) output_script = self.getScriptDest(script_lock) locked_n = findOutput(tx_lock, output_script) ensure(locked_n is not None, 'Output not found in tx') locked_coin = tx_lock.vout[locked_n].nValue tx_lock.rehash() tx_lock_id_int = tx_lock.sha256 tx = CTransaction() tx.nVersion = self.txVersion() tx.vin.append(CTxIn(COutPoint(tx_lock_id_int, locked_n), scriptSig=self.getScriptScriptSig(script_lock))) tx.vout.append(self.txoType()(locked_coin, self.getScriptForPubkeyHash(pkh_dest))) dummy_witness_stack = self.getScriptLockTxDummyWitness(script_lock) witness_bytes = self.getWitnessStackSerialisedLength(dummy_witness_stack) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) pay_fee = round(tx_fee_rate * vsize / 1000) tx.vout[0].nValue = locked_coin - pay_fee fee_info['fee_paid'] = pay_fee fee_info['rate_used'] = tx_fee_rate fee_info['witness_bytes'] = witness_bytes fee_info['vsize'] = vsize tx.rehash() self._log.info('createSCLockSpendTx %s:\n fee_rate, vsize, fee: %ld, %ld, %ld.', i2h(tx.sha256), tx_fee_rate, vsize, pay_fee) return tx.serialize()