#!/usr/bin/env python # -*- coding: utf-8 -*- # Copyright (c) 2020-2021 tecnovert # Distributed under the MIT software license, see the accompanying # file LICENSE or http://www.opensource.org/licenses/mit-license.php. import time import base64 import hashlib import logging from io import BytesIO from basicswap.contrib.test_framework import segwit_addr from .util import ( decodeScriptNum, getCompactSizeLen, SerialiseNumCompact, dumpj, format_amount, make_int, toWIF, assert_cond, decodeAddress) from coincurve.keys import ( PrivateKey, PublicKey) from coincurve.dleag import ( verify_secp256k1_point) from coincurve.ecdsaotves import ( ecdsaotves_enc_sign, ecdsaotves_enc_verify, ecdsaotves_dec_sig, ecdsaotves_rec_enc_key) from .ecc_util import ( G, ep, pointToCPK, CPKToPoint, getSecretInt, b2h, i2b, b2i, i2h) from .contrib.test_framework.messages import ( COIN, COutPoint, CTransaction, CTxIn, CTxInWitness, CTxOut, FromHex) from .contrib.test_framework.script import ( CScript, CScriptOp, OP_IF, OP_ELSE, OP_ENDIF, OP_0, OP_2, OP_CHECKSIG, OP_CHECKMULTISIG, OP_CHECKSEQUENCEVERIFY, OP_DROP, SIGHASH_ALL, SegwitV0SignatureHash, hash160) from .types import ( SEQUENCE_LOCK_BLOCKS, SEQUENCE_LOCK_TIME) from .chainparams import CoinInterface, Coins, chainparams from .rpc import make_rpc_func SEQUENCE_LOCKTIME_GRANULARITY = 9 # 512 seconds SEQUENCE_LOCKTIME_TYPE_FLAG = (1 << 22) SEQUENCE_LOCKTIME_MASK = 0x0000ffff def findOutput(tx, script_pk): for i in range(len(tx.vout)): if tx.vout[i].scriptPubKey == script_pk: return i return None class BTCInterface(CoinInterface): @staticmethod def coin_type(): return Coins.BTC @staticmethod def COIN(): return COIN @staticmethod def exp(): return 8 @staticmethod def nbk(): return 32 @staticmethod def nbK(): # No. of bytes requires to encode a public key return 33 @staticmethod def witnessScaleFactor(): return 4 @staticmethod def txVersion(): return 2 @staticmethod def getTxOutputValue(tx): rv = 0 for output in tx.vout: rv += output.nValue return rv @staticmethod def compareFeeRates(a, b): return abs(a - b) < 20 @staticmethod def xmr_swap_alock_spend_tx_vsize(): return 147 @staticmethod def txoType(): return CTxOut @staticmethod def getExpectedSequence(lockType, lockVal): assert(lockVal >= 1), 'Bad lockVal' if lockType == SEQUENCE_LOCK_BLOCKS: return lockVal if lockType == SEQUENCE_LOCK_TIME: secondsLocked = lockVal # Ensure the locked time is never less than lockVal if secondsLocked % (1 << SEQUENCE_LOCKTIME_GRANULARITY) != 0: secondsLocked += (1 << SEQUENCE_LOCKTIME_GRANULARITY) secondsLocked >>= SEQUENCE_LOCKTIME_GRANULARITY return secondsLocked | SEQUENCE_LOCKTIME_TYPE_FLAG raise ValueError('Unknown lock type') @staticmethod def decodeSequence(lock_value): # Return the raw value if lock_value & SEQUENCE_LOCKTIME_TYPE_FLAG: return (lock_value & SEQUENCE_LOCKTIME_MASK) << SEQUENCE_LOCKTIME_GRANULARITY return lock_value & SEQUENCE_LOCKTIME_MASK def __init__(self, coin_settings, network, swap_client=None): super().__init__() rpc_host = coin_settings.get('rpchost', '127.0.0.1') self.rpc_callback = make_rpc_func(coin_settings['rpcport'], coin_settings['rpcauth'], host=rpc_host) self._network = network self.blocks_confirmed = coin_settings['blocks_confirmed'] self.setConfTarget(coin_settings['conf_target']) self._sc = swap_client self._log = self._sc.log if self._sc and self._sc.log else logging def setConfTarget(self, new_conf_target): assert(new_conf_target >= 1 and new_conf_target < 33), 'Invalid conf_target value' self._conf_target = new_conf_target def testDaemonRPC(self): self.rpc_callback('getwalletinfo', []) def getDaemonVersion(self): return self.rpc_callback('getnetworkinfo')['version'] def getBlockchainInfo(self): return self.rpc_callback('getblockchaininfo') def getChainHeight(self): return self.rpc_callback('getblockchaininfo')['blocks'] def getMempoolTx(self, txid): return self.rpc_callback('getrawtransaction', [txid.hex()]) def getBlockHeaderFromHeight(self, height): block_hash = self.rpc_callback('getblockhash', [height]) return self.rpc_callback('getblockheader', [block_hash]) def getBlockHeader(self, block_hash): return self.rpc_callback('getblockheader', [block_hash]) def initialiseWallet(self, key_bytes): wif_prefix = chainparams[self.coin_type()][self._network]['key_prefix'] key_wif = toWIF(wif_prefix, key_bytes) try: self.rpc_callback('sethdseed', [True, key_wif]) except Exception as e: # < 0.21: Cannot set a new HD seed while still in Initial Block Download. self._log.error('sethdseed failed: {}'.format(str(e))) def getWalletInfo(self): return self.rpc_callback('getwalletinfo') def getWalletSeedID(self): return self.rpc_callback('getwalletinfo')['hdseedid'] def getNewAddress(self, use_segwit): args = ['swap_receive'] if use_segwit: args.append('bech32') return self.rpc_callback('getnewaddress', args) def get_fee_rate(self, conf_target=2): try: return self.rpc_callback('estimatesmartfee', [conf_target])['feerate'], 'estimatesmartfee' except Exception: try: fee_rate = self.rpc_callback('getwalletinfo')['paytxfee'], 'paytxfee' assert(fee_rate > 0.0), '0 feerate' return fee_rate except Exception: return self.rpc_callback('getnetworkinfo')['relayfee'], 'relayfee' def decodeAddress(self, address): bech32_prefix = chainparams[self.coin_type()][self._network]['hrp'] if address.startswith(bech32_prefix): return bytes(segwit_addr.decode(bech32_prefix, address)[1]) return decodeAddress(address)[1:] def getNewSecretKey(self): return getSecretInt() def pubkey(self, key): return G * key def getPubkey(self, privkey): return PublicKey.from_secret(privkey).format() def getAddressHashFromKey(self, key): pk = self.getPubkey(key) return hash160(pk) def verifyKey(self, k): i = b2i(k) return(i < ep.o and i > 0) def verifyPubkey(self, pubkey_bytes): return verify_secp256k1_point(pubkey_bytes) def encodePubkey(self, pk): return pointToCPK(pk) def decodePubkey(self, pke): return CPKToPoint(pke) def decodeKey(self, k): i = b2i(k) assert(i < ep.o) return i def sumKeys(self, ka, kb): return (ka + kb) % ep.o def sumPubkeys(self, Ka, Kb): return Ka + Kb def getScriptForPubkeyHash(self, pkh): return CScript([OP_0, pkh]) def extractScriptLockScriptValues(self, script_bytes): script_len = len(script_bytes) assert_cond(script_len == 71, 'Bad script length') o = 0 assert_cond(script_bytes[o] == OP_2) assert_cond(script_bytes[o + 1] == 33) o += 2 pk1 = script_bytes[o: o + 33] o += 33 assert_cond(script_bytes[o] == 33) o += 1 pk2 = script_bytes[o: o + 33] o += 33 assert_cond(script_bytes[o] == OP_2) assert_cond(script_bytes[o + 1] == OP_CHECKMULTISIG) return pk1, pk2 def genScriptLockTxScript(self, Kal, Kaf): Kal_enc = Kal if len(Kal) == 33 else self.encodePubkey(Kal) Kaf_enc = Kaf if len(Kaf) == 33 else self.encodePubkey(Kaf) return CScript([2, Kal_enc, Kaf_enc, 2, CScriptOp(OP_CHECKMULTISIG)]) def createScriptLockTx(self, value, Kal, Kaf): script = self.genScriptLockTxScript(Kal, Kaf) tx = CTransaction() tx.nVersion = self.txVersion() tx.vout.append(self.txoType()(value, self.getScriptDest(script))) return tx.serialize(), script def extractScriptLockRefundScriptValues(self, script_bytes): script_len = len(script_bytes) assert_cond(script_len > 73, 'Bad script length') assert_cond(script_bytes[0] == OP_IF) assert_cond(script_bytes[1] == OP_2) assert_cond(script_bytes[2] == 33) pk1 = script_bytes[3: 3 + 33] assert_cond(script_bytes[36] == 33) pk2 = script_bytes[37: 37 + 33] assert_cond(script_bytes[70] == OP_2) assert_cond(script_bytes[71] == OP_CHECKMULTISIG) assert_cond(script_bytes[72] == OP_ELSE) o = 73 csv_val, nb = decodeScriptNum(script_bytes, o) o += nb assert_cond(script_len == o + 5 + 33, 'Bad script length') # Fails if script too long assert_cond(script_bytes[o] == OP_CHECKSEQUENCEVERIFY) o += 1 assert_cond(script_bytes[o] == OP_DROP) o += 1 assert_cond(script_bytes[o] == 33) o += 1 pk3 = script_bytes[o: o + 33] o += 33 assert_cond(script_bytes[o] == OP_CHECKSIG) o += 1 assert_cond(script_bytes[o] == OP_ENDIF) return pk1, pk2, csv_val, pk3 def genScriptLockRefundTxScript(self, Kal, Kaf, csv_val): Kal_enc = Kal if len(Kal) == 33 else self.encodePubkey(Kal) Kaf_enc = Kaf if len(Kaf) == 33 else self.encodePubkey(Kaf) return CScript([ CScriptOp(OP_IF), 2, Kal_enc, Kaf_enc, 2, CScriptOp(OP_CHECKMULTISIG), CScriptOp(OP_ELSE), csv_val, CScriptOp(OP_CHECKSEQUENCEVERIFY), CScriptOp(OP_DROP), Kaf_enc, CScriptOp(OP_CHECKSIG), CScriptOp(OP_ENDIF)]) def createScriptLockRefundTx(self, tx_lock_bytes, script_lock, Kal, Kaf, lock1_value, csv_val, tx_fee_rate): tx_lock = CTransaction() tx_lock = FromHex(tx_lock, tx_lock_bytes.hex()) output_script = CScript([OP_0, hashlib.sha256(script_lock).digest()]) locked_n = findOutput(tx_lock, output_script) assert_cond(locked_n is not None, 'Output not found in tx') locked_coin = tx_lock.vout[locked_n].nValue tx_lock.rehash() tx_lock_hash_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_hash_int, locked_n), nSequence=lock1_value)) tx.vout.append(self.txoType()(locked_coin, CScript([OP_0, hashlib.sha256(refund_script).digest()]))) witness_bytes = len(script_lock) witness_bytes += 74 * 2 # 2 signatures (72 + 1 byte sighashtype + 1 byte size) - Use maximum txn size for estimate witness_bytes += 2 # 2 empty witness stack values witness_bytes += getCompactSizeLen(witness_bytes) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) pay_fee = int(tx_fee_rate * vsize / 1000) tx.vout[0].nValue = locked_coin - pay_fee tx.rehash() self._log.info('createScriptLockRefundTx %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 createScriptLockRefundSpendTx(self, tx_lock_refund_bytes, script_lock_refund, pkh_refund_to, tx_fee_rate): # 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 = CScript([OP_0, hashlib.sha256(script_lock_refund).digest()]) locked_n = findOutput(tx_lock_refund, output_script) assert_cond(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)) tx.vout.append(self.txoType()(locked_coin, self.getScriptForPubkeyHash(pkh_refund_to))) witness_bytes = len(script_lock_refund) witness_bytes += 74 * 2 # 2 signatures (72 + 1 byte sighashtype + 1 byte size) - Use maximum txn size for estimate witness_bytes += 4 # 1 empty, 1 true witness stack values witness_bytes += getCompactSizeLen(witness_bytes) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) pay_fee = int(tx_fee_rate * vsize / 1000) tx.vout[0].nValue = locked_coin - pay_fee tx.rehash() self._log.info('createScriptLockRefundSpendTx %s:\n fee_rate, vsize, fee: %ld, %ld, %ld.', i2h(tx.sha256), tx_fee_rate, vsize, pay_fee) return tx.serialize() def createScriptLockRefundSpendToFTx(self, tx_lock_refund_bytes, script_lock_refund, pkh_dest, tx_fee_rate): # Sends the coinA locked coin to the follower tx_lock_refund = self.loadTx(tx_lock_refund_bytes) output_script = CScript([OP_0, hashlib.sha256(script_lock_refund).digest()]) locked_n = findOutput(tx_lock_refund, output_script) assert_cond(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)) tx.vout.append(self.txoType()(locked_coin, self.getScriptForPubkeyHash(pkh_dest))) witness_bytes = len(script_lock_refund) witness_bytes += 74 # 2 signatures (72 + 1 byte sighashtype + 1 byte size) - Use maximum txn size for estimate witness_bytes += 1 # 1 empty stack value witness_bytes += getCompactSizeLen(witness_bytes) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) pay_fee = int(tx_fee_rate * vsize / 1000) tx.vout[0].nValue = locked_coin - pay_fee tx.rehash() self._log.info('createScriptLockRefundSpendToFTx %s:\n fee_rate, vsize, fee: %ld, %ld, %ld.', i2h(tx.sha256), tx_fee_rate, vsize, pay_fee) return tx.serialize() def createScriptLockSpendTx(self, tx_lock_bytes, script_lock, pkh_dest, tx_fee_rate): tx_lock = self.loadTx(tx_lock_bytes) output_script = CScript([OP_0, hashlib.sha256(script_lock).digest()]) locked_n = findOutput(tx_lock, output_script) assert_cond(locked_n is not None, 'Output not found in tx') locked_coin = tx_lock.vout[locked_n].nValue tx_lock.rehash() tx_lock_hash_int = tx_lock.sha256 tx = CTransaction() tx.nVersion = self.txVersion() tx.vin.append(CTxIn(COutPoint(tx_lock_hash_int, locked_n))) tx.vout.append(self.txoType()(locked_coin, self.getScriptForPubkeyHash(pkh_dest))) witness_bytes = len(script_lock) witness_bytes += 33 # sv, size witness_bytes += 74 * 2 # 2 signatures (72 + 1 byte sighashtype + 1 byte size) - Use maximum txn size for estimate witness_bytes += 4 # 1 empty, 1 true witness stack values witness_bytes += getCompactSizeLen(witness_bytes) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) pay_fee = int(tx_fee_rate * vsize / 1000) tx.vout[0].nValue = locked_coin - pay_fee tx.rehash() self._log.info('createScriptLockSpendTx %s:\n fee_rate, vsize, fee: %ld, %ld, %ld.', i2h(tx.sha256), tx_fee_rate, vsize, pay_fee) return tx.serialize() def verifyLockTx(self, tx_bytes, script_out, swap_value, Kal, Kaf, feerate, check_lock_tx_inputs): # Verify: # # Not necessary to check the lock txn is mineable, as protocol will wait for it to confirm # However by checking early we can avoid wasting time processing unmineable txns # Check fee is reasonable tx = self.loadTx(tx_bytes) tx_hash = self.getTxHash(tx) self._log.info('Verifying lock tx: {}.'.format(b2h(tx_hash))) assert_cond(tx.nVersion == self.txVersion(), 'Bad version') assert_cond(tx.nLockTime == 0, 'Bad nLockTime') script_pk = CScript([OP_0, hashlib.sha256(script_out).digest()]) locked_n = findOutput(tx, script_pk) assert_cond(locked_n is not None, 'Output not found in tx') locked_coin = tx.vout[locked_n].nValue assert_cond(locked_coin == swap_value, 'Bad locked value') # Check script and values A, B = self.extractScriptLockScriptValues(script_out) assert_cond(A == Kal, 'Bad script pubkey') assert_cond(B == Kaf, 'Bad script pubkey') if check_lock_tx_inputs: # Check that inputs are unspent and verify fee rate inputs_value = 0 add_bytes = 0 add_witness_bytes = getCompactSizeLen(len(tx.vin)) for pi in tx.vin: ptx = self.rpc_callback('getrawtransaction', [i2h(pi.prevout.hash), True]) prevout = ptx['vout'][pi.prevout.n] inputs_value += make_int(prevout['value']) prevout_type = prevout['scriptPubKey']['type'] if prevout_type == 'witness_v0_keyhash': add_witness_bytes += 107 # sig 72, pk 33 and 2 size bytes add_witness_bytes += getCompactSizeLen(107) else: # Assume P2PKH, TODO more types add_bytes += 107 # OP_PUSH72 OP_PUSH33 outputs_value = 0 for txo in tx.vout: outputs_value += txo.nValue fee_paid = inputs_value - outputs_value assert(fee_paid > 0) vsize = self.getTxVSize(tx, add_bytes, add_witness_bytes) fee_rate_paid = fee_paid * 1000 / vsize self._log.info('tx amount, vsize, feerate: %ld, %ld, %ld', locked_coin, vsize, fee_rate_paid) if not self.compareFeeRates(fee_rate_paid, feerate): self._log.warning('feerate paid doesn\'t match expected: %ld, %ld', fee_rate_paid, feerate) # TODO: Display warning to user return tx_hash, locked_n def verifyLockRefundTx(self, tx_bytes, script_out, prevout_id, prevout_n, prevout_seq, prevout_script, Kal, Kaf, csv_val_expect, swap_value, feerate): # Verify: # Must have only one input with correct prevout and sequence # Must have only one output to the p2wsh of the lock refund script # Output value must be locked_coin - lock tx fee tx = self.loadTx(tx_bytes) tx_hash = self.getTxHash(tx) self._log.info('Verifying lock refund tx: {}.'.format(b2h(tx_hash))) assert_cond(tx.nVersion == self.txVersion(), 'Bad version') assert_cond(tx.nLockTime == 0, 'nLockTime not 0') assert_cond(len(tx.vin) == 1, 'tx doesn\'t have one input') assert_cond(tx.vin[0].nSequence == prevout_seq, 'Bad input nSequence') assert_cond(len(tx.vin[0].scriptSig) == 0, 'Input scriptsig not empty') assert_cond(tx.vin[0].prevout.hash == b2i(prevout_id) and tx.vin[0].prevout.n == prevout_n, 'Input prevout mismatch') assert_cond(len(tx.vout) == 1, 'tx doesn\'t have one output') script_pk = CScript([OP_0, hashlib.sha256(script_out).digest()]) locked_n = findOutput(tx, script_pk) assert_cond(locked_n is not None, 'Output not found in tx') locked_coin = tx.vout[locked_n].nValue # Check script and values A, B, csv_val, C = self.extractScriptLockRefundScriptValues(script_out) assert_cond(A == Kal, 'Bad script pubkey') assert_cond(B == Kaf, 'Bad script pubkey') assert_cond(csv_val == csv_val_expect, 'Bad script csv value') assert_cond(C == Kaf, 'Bad script pubkey') fee_paid = swap_value - locked_coin assert(fee_paid > 0) witness_bytes = len(prevout_script) witness_bytes += 74 * 2 # 2 signatures (72 + 1 byte sighashtype + 1 byte size) - Use maximum txn size for estimate witness_bytes += 2 # 2 empty witness stack values witness_bytes += getCompactSizeLen(witness_bytes) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) fee_rate_paid = fee_paid * 1000 / vsize self._log.info('tx amount, vsize, feerate: %ld, %ld, %ld', locked_coin, vsize, fee_rate_paid) if not self.compareFeeRates(fee_rate_paid, feerate): raise ValueError('Bad fee rate, expected: {}'.format(feerate)) return tx_hash, locked_coin def verifyLockRefundSpendTx(self, tx_bytes, lock_refund_tx_id, prevout_script, Kal, prevout_value, feerate): # Verify: # Must have only one input with correct prevout (n is always 0) and sequence # Must have only one output sending lock refund tx value - fee to leader's address, TODO: follower shouldn't need to verify destination addr tx = self.loadTx(tx_bytes) tx_hash = self.getTxHash(tx) self._log.info('Verifying lock refund spend tx: {}.'.format(b2h(tx_hash))) assert_cond(tx.nVersion == self.txVersion(), 'Bad version') assert_cond(tx.nLockTime == 0, 'nLockTime not 0') assert_cond(len(tx.vin) == 1, 'tx doesn\'t have one input') assert_cond(tx.vin[0].nSequence == 0, 'Bad input nSequence') assert_cond(len(tx.vin[0].scriptSig) == 0, 'Input scriptsig not empty') assert_cond(tx.vin[0].prevout.hash == b2i(lock_refund_tx_id) and tx.vin[0].prevout.n == 0, 'Input prevout mismatch') assert_cond(len(tx.vout) == 1, 'tx doesn\'t have one output') # Destination doesn't matter to the follower ''' p2wpkh = CScript([OP_0, hash160(Kal)]) locked_n = findOutput(tx, p2wpkh) assert_cond(locked_n is not None, 'Output not found in lock refund spend tx') ''' tx_value = tx.vout[0].nValue fee_paid = prevout_value - tx_value assert(fee_paid > 0) witness_bytes = len(prevout_script) witness_bytes += 74 * 2 # 2 signatures (72 + 1 byte sighashtype + 1 byte size) - Use maximum txn size for estimate witness_bytes += 4 # 1 empty, 1 true witness stack values witness_bytes += getCompactSizeLen(witness_bytes) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) fee_rate_paid = fee_paid * 1000 / vsize self._log.info('tx amount, vsize, feerate: %ld, %ld, %ld', tx_value, vsize, fee_rate_paid) if not self.compareFeeRates(fee_rate_paid, feerate): raise ValueError('Bad fee rate, expected: {}'.format(feerate)) return True def verifyLockSpendTx(self, tx_bytes, lock_tx_bytes, lock_tx_script, a_pkhash_f, feerate): # Verify: # Must have only one input with correct prevout (n is always 0) and sequence # Must have only one output with destination and amount tx = self.loadTx(tx_bytes) tx_hash = self.getTxHash(tx) self._log.info('Verifying lock spend tx: {}.'.format(b2h(tx_hash))) assert_cond(tx.nVersion == self.txVersion(), 'Bad version') assert_cond(tx.nLockTime == 0, 'nLockTime not 0') assert_cond(len(tx.vin) == 1, 'tx doesn\'t have one input') lock_tx = self.loadTx(lock_tx_bytes) lock_tx_id = self.getTxHash(lock_tx) output_script = CScript([OP_0, hashlib.sha256(lock_tx_script).digest()]) locked_n = findOutput(lock_tx, output_script) assert_cond(locked_n is not None, 'Output not found in tx') locked_coin = lock_tx.vout[locked_n].nValue assert_cond(tx.vin[0].nSequence == 0, 'Bad input nSequence') assert_cond(len(tx.vin[0].scriptSig) == 0, 'Input scriptsig not empty') assert_cond(tx.vin[0].prevout.hash == b2i(lock_tx_id) and tx.vin[0].prevout.n == locked_n, 'Input prevout mismatch') assert_cond(len(tx.vout) == 1, 'tx doesn\'t have one output') p2wpkh = self.getScriptForPubkeyHash(a_pkhash_f) assert_cond(tx.vout[0].scriptPubKey == p2wpkh, 'Bad output destination') fee_paid = locked_coin - tx.vout[0].nValue assert(fee_paid > 0) witness_bytes = len(lock_tx_script) witness_bytes += 33 # sv, size witness_bytes += 74 * 2 # 2 signatures (72 + 1 byte sighashtype + 1 byte size) - Use maximum txn size for estimate witness_bytes += 4 # 1 empty, 1 true witness stack values witness_bytes += getCompactSizeLen(witness_bytes) vsize = self.getTxVSize(tx, add_witness_bytes=witness_bytes) fee_rate_paid = fee_paid * 1000 / vsize self._log.info('tx amount, vsize, feerate: %ld, %ld, %ld', tx.vout[0].nValue, vsize, fee_rate_paid) if not self.compareFeeRates(fee_rate_paid, feerate): raise ValueError('Bad fee rate, expected: {}'.format(feerate)) return True def signTx(self, key_bytes, tx_bytes, prevout_n, prevout_script, prevout_value): tx = self.loadTx(tx_bytes) sig_hash = SegwitV0SignatureHash(prevout_script, tx, prevout_n, SIGHASH_ALL, prevout_value) eck = PrivateKey(key_bytes) return eck.sign(sig_hash, hasher=None) + bytes((SIGHASH_ALL,)) def signTxOtVES(self, key_sign, pubkey_encrypt, tx_bytes, prevout_n, prevout_script, prevout_value): tx = self.loadTx(tx_bytes) sig_hash = SegwitV0SignatureHash(prevout_script, tx, prevout_n, SIGHASH_ALL, prevout_value) return ecdsaotves_enc_sign(key_sign, pubkey_encrypt, sig_hash) def verifyTxOtVES(self, tx_bytes, ct, Ks, Ke, prevout_n, prevout_script, prevout_value): tx = self.loadTx(tx_bytes) sig_hash = SegwitV0SignatureHash(prevout_script, tx, prevout_n, SIGHASH_ALL, prevout_value) return ecdsaotves_enc_verify(Ks, Ke, sig_hash, ct) def decryptOtVES(self, k, esig): return ecdsaotves_dec_sig(k, esig) + bytes((SIGHASH_ALL,)) def verifyTxSig(self, tx_bytes, sig, K, prevout_n, prevout_script, prevout_value): tx = self.loadTx(tx_bytes) sig_hash = SegwitV0SignatureHash(prevout_script, tx, prevout_n, SIGHASH_ALL, prevout_value) pubkey = PublicKey(K) return pubkey.verify(sig[: -1], sig_hash, hasher=None) # Pop the hashtype byte def verifySig(self, pubkey, signed_hash, sig): pubkey = PublicKey(pubkey) return pubkey.verify(sig, signed_hash, hasher=None) def fundTx(self, tx, feerate): feerate_str = format_amount(feerate, self.exp()) # TODO: unlock unspents if bid cancelled options = { 'lockUnspents': True, 'feeRate': feerate_str, } rv = self.rpc_callback('fundrawtransaction', [tx.hex(), options]) return bytes.fromhex(rv['hex']) def unlockInputs(self, tx_bytes): tx = self.loadTx(tx_bytes) inputs = [] for pi in tx.vin: inputs.append({'txid': i2h(pi.prevout.hash), 'vout': pi.prevout.n}) self.rpc_callback('lockunspent', [True, inputs]) def signTxWithWallet(self, tx): rv = self.rpc_callback('signrawtransactionwithwallet', [tx.hex()]) return bytes.fromhex(rv['hex']) def publishTx(self, tx): return self.rpc_callback('sendrawtransaction', [tx.hex()]) def encodeTx(self, tx): return tx.serialize() def loadTx(self, tx_bytes): # Load tx from bytes to internal representation tx = CTransaction() tx.deserialize(BytesIO(tx_bytes)) return tx def getTxHash(self, tx): if isinstance(tx, bytes): tx = self.loadTx(tx) tx.rehash() return i2b(tx.sha256) def getTxOutputPos(self, tx, script): if isinstance(tx, bytes): tx = self.loadTx(tx) script_pk = CScript([OP_0, hashlib.sha256(script).digest()]) return findOutput(tx, script_pk) def getPubkeyHash(self, K): return hash160(self.encodePubkey(K)) def getScriptDest(self, script): return CScript([OP_0, hashlib.sha256(script).digest()]) def getPkDest(self, K): return self.getScriptForPubkeyHash(self.getPubkeyHash(K)) def scanTxOutset(self, dest): return self.rpc_callback('scantxoutset', ['start', ['raw({})'.format(dest.hex())]]) def getTransaction(self, txid): try: return bytes.fromhex(self.rpc_callback('getrawtransaction', [txid.hex()])) except Exception as ex: # TODO: filter errors return None def getWalletTransaction(self, txid): try: return bytes.fromhex(self.rpc_callback('gettransaction', [txid.hex()])) except Exception as ex: # TODO: filter errors return None def setTxSignature(self, tx_bytes, stack): tx = self.loadTx(tx_bytes) tx.wit.vtxinwit.clear() tx.wit.vtxinwit.append(CTxInWitness()) tx.wit.vtxinwit[0].scriptWitness.stack = stack return tx.serialize() def extractLeaderSig(self, tx_bytes): tx = self.loadTx(tx_bytes) return tx.wit.vtxinwit[0].scriptWitness.stack[1] def extractFollowerSig(self, tx_bytes): tx = self.loadTx(tx_bytes) return tx.wit.vtxinwit[0].scriptWitness.stack[2] def createBLockTx(self, Kbs, output_amount): tx = CTransaction() tx.nVersion = self.txVersion() p2wpkh = self.getPkDest(Kbs) tx.vout.append(self.txoType()(output_amount, p2wpkh)) return tx.serialize() def publishBLockTx(self, Kbv, Kbs, output_amount, feerate): b_lock_tx = self.createBLockTx(Kbs, output_amount) b_lock_tx = self.fundTx(b_lock_tx, feerate) b_lock_tx_id = self.getTxHash(b_lock_tx) b_lock_tx = self.signTxWithWallet(b_lock_tx) return self.publishTx(b_lock_tx) def recoverEncKey(self, esig, sig, K): return ecdsaotves_rec_enc_key(K, esig, sig[:-1]) # Strip sighash type def getTxVSize(self, tx, add_bytes=0, add_witness_bytes=0): wsf = self.witnessScaleFactor() len_full = len(tx.serialize_with_witness()) + add_bytes + add_witness_bytes len_nwit = len(tx.serialize_without_witness()) + add_bytes weight = len_nwit * (wsf - 1) + len_full return (weight + wsf - 1) // wsf def findTxB(self, kbv, Kbs, cb_swap_value, cb_block_confirmed, restore_height): raw_dest = self.getPkDest(Kbs) rv = self.scanTxOutset(raw_dest) print('scanTxOutset', dumpj(rv)) for utxo in rv['unspents']: if 'height' in utxo and utxo['height'] > 0 and rv['height'] - utxo['height'] > cb_block_confirmed: if self.make_int(utxo['amount']) != cb_swap_value: self._log.warning('Found output to lock tx pubkey of incorrect value: %s', str(utxo['amount'])) else: return {'txid': utxo['txid'], 'vout': utxo['vout'], 'amount': utxo['amount'], 'height': utxo['height']} return None def waitForLockTxB(self, kbv, Kbs, cb_swap_value, cb_block_confirmed): raw_dest = self.getPkDest(Kbs) for i in range(20): time.sleep(1) rv = self.scanTxOutset(raw_dest) print('scanTxOutset', dumpj(rv)) for utxo in rv['unspents']: if 'height' in utxo and utxo['height'] > 0 and rv['height'] - utxo['height'] > cb_block_confirmed: if self.make_int(utxo['amount']) != cb_swap_value: self._log.warning('Found output to lock tx pubkey of incorrect value: %s', str(utxo['amount'])) else: return True return False def spendBLockTx(self, address_to, kbv, kbs, cb_swap_value, b_fee, restore_height): print('TODO: spendBLockTx') def getOutput(self, txid, dest_script, expect_value): # TODO: Use getrawtransaction if txindex is active utxos = self.rpc_callback('scantxoutset', ['start', ['raw({})'.format(dest_script.hex())]]) chain_height = utxos['height'] rv = [] for utxo in utxos['unspents']: if txid and txid.hex() != utxo['txid']: continue if expect_value != self.make_int(utxo['amount']): continue rv.append({ 'depth': 0 if 'height' not in utxo else (chain_height - utxo['height']) + 1, 'height': 0 if 'height' not in utxo else utxo['height'], 'amount': self.make_int(utxo['amount']), 'txid': utxo['txid'], 'vout': utxo['vout']}) return rv, chain_height def withdrawCoin(self, value, addr_to, subfee): params = [addr_to, value, '', '', subfee, True, self._conf_target] return self.rpc_callback('sendtoaddress', params) def signCompact(self, k, message): message_hash = hashlib.sha256(bytes(message, 'utf-8')).digest() privkey = PrivateKey(k) return privkey.sign_recoverable(message_hash, hasher=None)[:64] def verifyCompact(self, K, message, sig): message_hash = hashlib.sha256(bytes(message, 'utf-8')).digest() pubkey = PublicKey(K) rv = pubkey.verify_compact(sig, message_hash, hasher=None) assert(rv is True) def verifyMessage(self, address, message, signature, message_magic=None): if message_magic is None: message_magic = chainparams[self.coin_type()]['message_magic'] message_bytes = SerialiseNumCompact(len(message_magic)) + bytes(message_magic, 'utf-8') + SerialiseNumCompact(len(message)) + bytes(message, 'utf-8') message_hash = hashlib.sha256(hashlib.sha256(message_bytes).digest()).digest() signature_bytes = base64.b64decode(signature) rec_id = (signature_bytes[0] - 27) & 3 signature_bytes = signature_bytes[1:] + bytes((rec_id,)) try: pubkey = PublicKey.from_signature_and_message(signature_bytes, message_hash, hasher=None) except Exception as e: self._log.info('verifyMessage failed: ' + str(e)) return False address_hash = self.decodeAddress(address) pubkey_hash = hash160(pubkey.format()) return True if address_hash == pubkey_hash else False def testBTCInterface(): print('testBTCInterface') if __name__ == "__main__": testBTCInterface()