707 lines
21 KiB
Python
707 lines
21 KiB
Python
import hashlib
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from binascii import hexlify, unhexlify
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import time
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import struct
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import hmac
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from .constants import *
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from .opcodes import *
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from .hash import *
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from .encode import *
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# Bitcoin keys/ addresses
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#
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def create_priv(hex=False):
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"""
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:return: 32 bytes private key
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"""
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q = time.time()
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rnd = random.SystemRandom()
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a = rnd.randint(0,MAX_INT_PRIVATE_KEY)
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i = int((time.time()%0.01)*100000)
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h = a.to_bytes(32,byteorder="big")
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while True:
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h = hashlib.sha256(h).digest()
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if i>1: i -= 1
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else:
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if int.from_bytes(h,byteorder="big")<MAX_INT_PRIVATE_KEY:
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break
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if hex:
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return hexlify(h).decode()
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return h
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def priv_from_int(k):
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return int.to_bytes(k,byteorder="big",length=32)
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def priv2WIF(h, compressed = True, testnet = False):
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#uncompressed: 0x80 + [32-byte secret] + [4 bytes of Hash() of previous 33 bytes], base58 encoded
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#compressed: 0x80 + [32-byte secret] + 0x01 + [4 bytes of Hash() previous 34 bytes], base58 encoded
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if type(h) == str:
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h = unhexlify(h)
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if testnet:
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h = TESTNET_PRIVATE_KEY_BYTE_PREFIX + h
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else:
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h = MAINNET_PRIVATE_KEY_BYTE_PREFIX + h
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if compressed: h += b'\x01'
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h += double_sha256(h)[:4]
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return encode_base58(h)
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def WIF2priv(h, hex = False, verify = 1):
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if verify:
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assert is_WIF_valid(h)
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h = decode_base58(h)
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if hex:
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return hexlify(h[1:33]).decode()
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return h[1:33]
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def is_WIF_valid(wif):
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if wif[0] not in PRIVATE_KEY_PREFIX_LIST:
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return False
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try:
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h = decode_base58(wif)
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except:
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return False
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checksum = h[-4:]
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if wif[0] in (MAINNET_PRIVATE_KEY_UNCOMPRESSED_PREFIX,
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TESTNET_PRIVATE_KEY_UNCOMPRESSED_PREFIX):
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if len(h) != 37:
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return False
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elif len(h) != 38:
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return False
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if double_sha256(h[:-4])[:4] != checksum:
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return False
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return True
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def priv2pub(private_key, compressed = True, hex = False):
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if type(private_key)!= bytes:
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if type(private_key) == bytearray:
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private_key = bytes(private_key)
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elif type(private_key) == str:
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if not is_WIF_valid(private_key):
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private_key = unhexlify(private_key)
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else:
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if private_key[0] in (MAINNET_PRIVATE_KEY_UNCOMPRESSED_PREFIX,
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TESTNET_PRIVATE_KEY_UNCOMPRESSED_PREFIX):
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compressed = False
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private_key = WIF2priv(private_key, verify=0)
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else:
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raise TypeError("private key must be a bytes or WIF or hex encoded string")
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pubkey_ptr = ffi.new('secp256k1_pubkey *')
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r = secp256k1.secp256k1_ec_pubkey_create(ECDSA_CONTEXT_ALL, pubkey_ptr, private_key)
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assert r == 1
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len_key = 33 if compressed else 65
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pubkey = ffi.new('char [%d]' % len_key)
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outlen = ffi.new('size_t *', len_key)
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compflag = EC_COMPRESSED if compressed else EC_UNCOMPRESSED
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r = secp256k1.secp256k1_ec_pubkey_serialize(ECDSA_CONTEXT_VERIFY, pubkey, outlen, pubkey_ptr, compflag)
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assert r == 1
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pub = bytes(ffi.buffer(pubkey, len_key))
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return hexlify(pub).decode() if hex else pub
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def is_valid_pub(key):
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if len(key) < 33:
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return False
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if key[0] == 0x04 and len(key) != 65:
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return False
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elif key[0] == 0x02 or key[0] == 0x03:
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if len(key) != 33:
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return False
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return True
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#
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# Bitcoin addresses
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#
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def hash2address(address_hash, testnet = False,
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script_hash = False, witness_version = 0):
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if type(address_hash) == str:
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address_hash = unhexlify(address_hash)
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if not script_hash:
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if witness_version is None:
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assert len(address_hash) == 20
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if testnet:
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prefix = TESTNET_ADDRESS_BYTE_PREFIX
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else:
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prefix = MAINNET_ADDRESS_BYTE_PREFIX
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address_hash = prefix + address_hash
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address_hash += double_sha256(address_hash)[:4]
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return encode_base58(address_hash)
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else:
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assert len(address_hash) in (20,32)
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if witness_version is None:
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if testnet:
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prefix = TESTNET_SCRIPT_ADDRESS_BYTE_PREFIX
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else:
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prefix = MAINNET_SCRIPT_ADDRESS_BYTE_PREFIX
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address_hash = prefix + address_hash
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address_hash += double_sha256(address_hash)[:4]
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return encode_base58(address_hash)
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if testnet:
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prefix = TESTNET_SEGWIT_ADDRESS_BYTE_PREFIX
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hrp = TESTNET_SEGWIT_ADDRESS_PREFIX
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else:
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prefix = MAINNET_SEGWIT_ADDRESS_BYTE_PREFIX
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hrp = MAINNET_SEGWIT_ADDRESS_PREFIX
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address_hash = witness_version.to_bytes(1, "big") + rebase_8_to_5( address_hash)
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checksum = bech32_polymod(prefix + address_hash + b"\x00" * 6)
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checksum = rebase_8_to_5(checksum.to_bytes(5, "big"))[2:]
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return "%s1%s" % (hrp, rebase_5_to_32(address_hash + checksum).decode())
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def address2hash(address, hex = False):
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if address[0] in ADDRESS_PREFIX_LIST:
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h = decode_base58(address)[1:-4]
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elif address[:2] in (MAINNET_SEGWIT_ADDRESS_PREFIX,
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TESTNET_SEGWIT_ADDRESS_PREFIX):
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address = address.split("1")[1]
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h = rebase_5_to_8(rebase_32_to_5(address)[1:-6], False)
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else:
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return None
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if hex:
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return h.hex()
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else:
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return h
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def get_witness_version(address):
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address = address.split("1")[1]
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h = rebase_32_to_5(address)
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return h[0]
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def address_type(address, num = False):
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if address[0] in (TESTNET_SCRIPT_ADDRESS_PREFIX,
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MAINNET_SCRIPT_ADDRESS_PREFIX):
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t = 'P2SH'
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elif address[0] in (MAINNET_ADDRESS_PREFIX,
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TESTNET_ADDRESS_PREFIX,
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TESTNET_ADDRESS_PREFIX_2):
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t = 'P2PKH'
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elif address[:2] in (MAINNET_SEGWIT_ADDRESS_PREFIX,
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TESTNET_SEGWIT_ADDRESS_PREFIX):
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if len(address) == 42:
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t = 'P2WPKH'
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elif len(address) == 62:
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t = 'P2WSH'
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else:
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return SCRIPT_TYPES['NON_STANDARD'] if num else 'UNKNOWN'
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else:
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return SCRIPT_TYPES['NON_STANDARD'] if num else 'UNKNOWN'
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return SCRIPT_TYPES[t] if num else t
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def script2hash(s, witness = False, hex = False):
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if type(s) == str:
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s = unhexlify(s)
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if witness:
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return sha256(s, hex)
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else:
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return hash160(s, hex)
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def address2script(address):
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if address[0] in (TESTNET_SCRIPT_ADDRESS_PREFIX,
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MAINNET_SCRIPT_ADDRESS_PREFIX):
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return OPCODE["OP_HASH160"] + b'\x14' + address2hash(address) + OPCODE["OP_EQUAL"]
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if address[0] in (MAINNET_ADDRESS_PREFIX,
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TESTNET_ADDRESS_PREFIX,
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TESTNET_ADDRESS_PREFIX_2):
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return OPCODE["OP_DUP"] + OPCODE["OP_HASH160"] + b'\x14' + \
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address2hash(address) + OPCODE["OP_EQUALVERIFY"] + OPCODE["OP_CHECKSIG"]
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if address[0] in (TESTNET_SEGWIT_ADDRESS_PREFIX,
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MAINNET_SEGWIT_ADDRESS_PREFIX):
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h = address2hash(address)
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return OPCODE["OP_0"] + bytes([len(h)]) + h
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raise Exception("Unknown address")
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def script_P2SH_P2WPKH(pubkey, hash = False):
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assert len(pubkey) == 33
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if hash:
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return hash160(b'\x00\x14' + hash160(pubkey))
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return b'\x00\x14' + hash160(pubkey)
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def pub2address(pubkey, testnet = False,
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p2sh_p2wpkh = False,
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witness_version = 0):
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if type(pubkey) == str:
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pubkey = unhexlify(pubkey)
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if p2sh_p2wpkh:
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assert len(pubkey) == 33
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h = hash160(b'\x00\x14' + hash160(pubkey))
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witness_version = None
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else:
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if witness_version is not None:
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assert len(pubkey) == 33
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h = hash160(pubkey)
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return hash2address(h, testnet = testnet,
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script_hash = p2sh_p2wpkh,
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witness_version = witness_version)
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# def pub2P2SH_P2WPKH_hash(pubkey):
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# return hash160(b'\x00\x14' + hash160(pubkey))
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#
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# def pub2P2SH_P2WPKH_address(pubkey, testnet = False):
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# return hash2address(pub2P2SH_P2WPKH_hash(pubkey),
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# testnet=testnet,
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# script_hash=True,
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# witness_version=None)
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def is_address_valid(address, testnet = False):
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if not address or type(address) != str:
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return False
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if address[0] in (MAINNET_ADDRESS_PREFIX,
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MAINNET_SCRIPT_ADDRESS_PREFIX,
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TESTNET_ADDRESS_PREFIX,
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TESTNET_ADDRESS_PREFIX_2,
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TESTNET_SCRIPT_ADDRESS_PREFIX):
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if testnet:
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if address[0] not in (TESTNET_ADDRESS_PREFIX,
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TESTNET_ADDRESS_PREFIX_2,
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TESTNET_SCRIPT_ADDRESS_PREFIX):
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return False
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else:
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if address[0] not in (MAINNET_ADDRESS_PREFIX,
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MAINNET_SCRIPT_ADDRESS_PREFIX):
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return False
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h = decode_base58(address)
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if len(h) != 25: return False
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checksum = h[-4:]
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if double_sha256(h[:-4])[:4] != checksum:
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return False
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return True
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elif address[:2].lower() in (TESTNET_SEGWIT_ADDRESS_PREFIX,
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MAINNET_SEGWIT_ADDRESS_PREFIX):
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if len(address) not in (42, 62):
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return False
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try:
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prefix, payload = address.split('1')
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except:
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return False
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upp = True if prefix[0].isupper() else False
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for i in payload[1:]:
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if upp:
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if not i.isupper() or i not in base32charset_upcase:
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return False
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else:
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if i.isupper() or i not in base32charset:
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return False
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payload = payload.lower()
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prefix = prefix.lower()
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if testnet:
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if prefix != TESTNET_SEGWIT_ADDRESS_PREFIX:
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return False
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stripped_prefix = TESTNET_SEGWIT_ADDRESS_BYTE_PREFIX
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else:
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if prefix != MAINNET_SEGWIT_ADDRESS_PREFIX:
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return False
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stripped_prefix = MAINNET_SEGWIT_ADDRESS_BYTE_PREFIX
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d = rebase_32_to_5(payload)
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address_hash = d[:-6]
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checksum = d[-6:]
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checksum2 = bech32_polymod(stripped_prefix + address_hash + b"\x00" * 6)
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checksum2 = rebase_8_to_5(checksum2.to_bytes(5, "big"))[2:]
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if checksum != checksum2:
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return False
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return True
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#
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# ECDSA
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#
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def verify_signature(sig, pubKey, msg):
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if type(sig) != bytes:
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if type(sig) == bytearray:
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sig = bytes(sig)
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elif type(sig) == str:
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sig = unhexlify(sig)
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else :
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raise TypeError("signature must be a bytes or hex encoded string")
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if type(pubKey) != bytes:
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if type(pubKey) == bytearray:
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pubKey = bytes(pubKey)
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elif type(pubKey) == str:
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pubKey = unhexlify(pubKey)
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else :
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raise TypeError("public key must be a bytes or hex encoded string")
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if type(msg) != bytes:
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if type(msg) == bytearray:
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msg = bytes(msg)
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elif type(msg) == str:
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msg = unhexlify(msg)
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else:
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raise TypeError("message must be a bytes or hex encoded string")
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raw_sig = ffi.new('secp256k1_ecdsa_signature *')
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raw_pubkey = ffi.new('secp256k1_pubkey *')
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if not secp256k1.secp256k1_ecdsa_signature_parse_der(ECDSA_CONTEXT_VERIFY , raw_sig, sig, len(sig)):
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raise TypeError("signature must be DER encoded")
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if not secp256k1.secp256k1_ec_pubkey_parse(ECDSA_CONTEXT_VERIFY, raw_pubkey, pubKey, len(pubKey)):
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raise TypeError("public key format error")
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result = secp256k1.secp256k1_ecdsa_verify(ECDSA_CONTEXT_VERIFY, raw_sig, msg, raw_pubkey)
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return True if result else False
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def sign_message(msg, private_key, hex = False):
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"""
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:param msg: message to sign
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:param private_key: private key (bytes, hex encoded string)
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:param hex:
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:return: DER encoded sinature
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"""
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if type(msg) != bytes:
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if type(msg) == bytearray:
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msg = bytes(msg)
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elif type(msg) == str:
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msg = unhexlify(msg)
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else :
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raise TypeError("message must be a bytes or hex encoded string")
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if type(private_key)!= bytes:
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if type(private_key) == bytearray:
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private_key = bytes(private_key)
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elif type(private_key) == str:
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private_key = unhexlify(private_key)
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else:
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raise TypeError("private key must be a bytes or hex encoded string")
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raw_sig = ffi.new('secp256k1_ecdsa_signature *')
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signed = secp256k1.secp256k1_ecdsa_sign(ECDSA_CONTEXT_SIGN, raw_sig, msg, private_key, ffi.NULL, ffi.NULL)
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assert signed == 1
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len_sig = 74
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output = ffi.new('unsigned char[%d]' % len_sig)
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outputlen = ffi.new('size_t *', len_sig)
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res = secp256k1.secp256k1_ecdsa_signature_serialize_der(ECDSA_CONTEXT_SIGN, output, outputlen, raw_sig)
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assert res == 1
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signature = bytes(ffi.buffer(output, outputlen[0]))
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return hexlify(signature).decode() if hex else signature
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def is_valid_signature_encoding(sig):
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# Format: 0x30 [total-length] 0x02 [R-length] [R] 0x02 [S-length] [S] [sighash]
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# * total-length: 1-byte length descriptor of everything that follows,
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# excluding the sighash byte.
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# * R-length: 1-byte length descriptor of the R value that follows.
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# * R: arbitrary-length big-endian encoded R value. It must use the shortest
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# possible encoding for a positive integers (which means no null bytes at
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# the start, except a single one when the next byte has its highest bit set).
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# * S-length: 1-byte length descriptor of the S value that follows.
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# * S: arbitrary-length big-endian encoded S value. The same rules apply.
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# * sighash: 1-byte value indicating what data is hashed (not part of the DER
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# signature)
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length = len(sig)
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# Minimum and maximum size constraints.
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if (length < 9) or (length > 73):
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return False
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# A signature is of type 0x30 (compound).
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if sig[0] != 0x30:
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return False
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# Make sure the length covers the entire signature.
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if sig[1] != (length - 3):
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return False
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# Extract the length of the R element.
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lenR = sig[3]
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# Make sure the length of the S element is still inside the signature.
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if (5 + lenR) >= length:
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return False
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# Extract the length of the S element.
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lenS = sig[5 + lenR]
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# Verify that the length of the signature matches the sum of the length
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# of the elements.
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if (lenR + lenS + 7) != length:
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return False
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# Check whether the R element is an integer.
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if sig[2] != 0x02:
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return False
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# Zero-length integers are not allowed for R.
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if lenR == 0:
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return False
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# Negative numbers are not allowed for R.
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if sig[4] & 0x80:
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return False
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# Null bytes at the start of R are not allowed, unless R would
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# otherwise be interpreted as a negative number.
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if (lenR > 1) and (sig[4] == 0x00) and (not sig[5] & 0x80):
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return False
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# Check whether the S element is an integer.
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if sig[lenR + 4] != 0x02:
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return False
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# Zero-length integers are not allowed for S.
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if lenS == 0:
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return False
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# Negative numbers are not allowed for S.
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if sig[lenR + 6] & 0x80:
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return False
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# Null bytes at the start of S are not allowed, unless S would otherwise be
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# interpreted as a negative number.
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if (lenS > 1) and (sig[lenR + 6] == 0x00) and (not sig[lenR + 7] & 0x80):
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return False
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return True
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#
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# Transaction encoding
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#
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def bits2target(bits):
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if type(bits) == str:
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bits = unhexlify(bits)
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if type(bits) == bytes:
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return int.from_bytes(bits[1:], 'big') * (2 ** (8 * (bits[0] - 3)))
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else:
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shift = bits >> 24
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target = (bits & 0xffffff) * (1 << (8 * (shift - 3)))
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return target
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def target2difficulty(target):
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return 0x00000000FFFF0000000000000000000000000000000000000000000000000000 / target
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def bits2difficulty(bits):
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return target2difficulty(bits2target(bits))
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def difficulty2target(difficulty):
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return int(0x00000000FFFF0000000000000000000000000000000000000000000000000000 / difficulty)
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def rh2s(tthash):
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return hexlify(tthash[::-1]).decode()
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def s2rh(hash_string):
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return unhexlify(hash_string)[::-1]
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|
def s2rh_step4(hash_string):
|
|
h = unhexlify(hash_string)
|
|
return reverse_hash(h)
|
|
|
|
def reverse_hash(h):
|
|
return struct.pack('>IIIIIIII', *struct.unpack('>IIIIIIII', h)[::-1])[::-1]
|
|
|
|
|
|
|
|
def merkleroot(tx_hash_list):
|
|
tx_hash_list = list(tx_hash_list)
|
|
if len(tx_hash_list) == 1:
|
|
return tx_hash_list[0]
|
|
while True:
|
|
new_hash_list = list()
|
|
while tx_hash_list:
|
|
h1 = tx_hash_list.pop(0)
|
|
try:
|
|
h2 = tx_hash_list.pop(0)
|
|
except:
|
|
h2 = h1
|
|
new_hash_list.append(double_sha256(h1 + h2))
|
|
if len(new_hash_list) > 1:
|
|
tx_hash_list = new_hash_list
|
|
else:
|
|
return new_hash_list[0]
|
|
|
|
def merkle_branches(tx_hash_list):
|
|
tx_hash_list = list(tx_hash_list)
|
|
branches = []
|
|
if len(tx_hash_list) == 1:
|
|
return []
|
|
tx_hash_list.pop(0)
|
|
while True:
|
|
branches.append(tx_hash_list.pop(0))
|
|
new_hash_list = list()
|
|
while tx_hash_list:
|
|
h1 = tx_hash_list.pop(0)
|
|
try:
|
|
h2 = tx_hash_list.pop(0)
|
|
except:
|
|
h2 = h1
|
|
new_hash_list.append(double_sha256(h1 + h2))
|
|
if len(new_hash_list) > 1:
|
|
tx_hash_list = new_hash_list
|
|
else:
|
|
if new_hash_list:
|
|
branches.append(new_hash_list.pop(0))
|
|
return branches
|
|
|
|
def merkleroot_from_branches(merkle_branches, coinbase_hash_bin):
|
|
merkle_root = coinbase_hash_bin
|
|
for h in merkle_branches:
|
|
if type(h) == str:
|
|
h = unhexlify(h)
|
|
merkle_root = double_sha256(merkle_root + h)
|
|
return merkle_root
|
|
#
|
|
#
|
|
#
|
|
|
|
|
|
def var_int(data):
|
|
e, s = 1, 0
|
|
if data[:1] == b'\xfd':
|
|
s, e = 1, 3
|
|
elif data[:1] == b'\xfe':
|
|
s = 1
|
|
e = 5
|
|
elif data[:1] == b'\xff':
|
|
s = 1
|
|
e = 9
|
|
i = int.from_bytes(data[s:e], byteorder='little', signed=False)
|
|
return (i, e)
|
|
|
|
|
|
def from_var_int(data):
|
|
# retrun
|
|
e = 1
|
|
s = 0
|
|
if data[:1] == b'\xfd':
|
|
s = 1
|
|
e = 3
|
|
elif data[:1] == b'\xfe':
|
|
s = 1
|
|
e = 5
|
|
elif data[:1] == b'\xff':
|
|
s = 1
|
|
e = 9
|
|
i = int.from_bytes(data[s:e], byteorder='little', signed=False)
|
|
return i
|
|
|
|
|
|
def var_int_len(byte):
|
|
e = 1
|
|
if byte == 253:
|
|
e = 3
|
|
elif byte == 254:
|
|
e = 5
|
|
elif byte == 255:
|
|
e = 9
|
|
return e
|
|
|
|
|
|
def to_var_int(i):
|
|
if i < 253:
|
|
return i.to_bytes(1, byteorder='little')
|
|
if i <= 0xffff:
|
|
return b'\xfd' + i.to_bytes(2, byteorder='little')
|
|
if i <= 0xffffffff:
|
|
return b'\xfe' + i.to_bytes(4, byteorder='little')
|
|
return b'\xff' + i.to_bytes(8, byteorder='little')
|
|
|
|
|
|
def read_var_int(stream):
|
|
l = stream.read(1)
|
|
bytes_length = var_int_len(l[0])
|
|
return l + stream.read(bytes_length - 1)
|
|
|
|
|
|
def read_var_list(stream, data_type):
|
|
count = from_var_int(read_var_int(stream))
|
|
return [data_type.deserialize(stream) for i in range(count)]
|
|
|
|
|
|
|
|
|
|
# generic big endian MPI format
|
|
def bn_bytes(v, have_ext=False):
|
|
ext = 0
|
|
if have_ext:
|
|
ext = 1
|
|
return ((v.bit_length() + 7) // 8) + ext
|
|
|
|
|
|
def bn2bin(v):
|
|
s = bytearray()
|
|
i = bn_bytes(v)
|
|
while i > 0:
|
|
s.append((v >> ((i - 1) * 8)) & 0xff)
|
|
i -= 1
|
|
return s
|
|
|
|
|
|
def bin2bn(s):
|
|
l = 0
|
|
for ch in s:
|
|
l = (l << 8) | ch
|
|
return l
|
|
|
|
|
|
def bn2mpi(v):
|
|
have_ext = False
|
|
if v.bit_length() > 0:
|
|
have_ext = (v.bit_length() & 0x07) == 0
|
|
|
|
neg = False
|
|
if v < 0:
|
|
neg = True
|
|
v = -v
|
|
|
|
s = struct.pack(b">I", bn_bytes(v, have_ext))
|
|
ext = bytearray()
|
|
if have_ext:
|
|
ext.append(0)
|
|
v_bin = bn2bin(v)
|
|
if neg:
|
|
if have_ext:
|
|
ext[0] |= 0x80
|
|
else:
|
|
v_bin[0] |= 0x80
|
|
return s + ext + v_bin
|
|
|
|
|
|
def mpi2bn(s):
|
|
if len(s) < 4:
|
|
return None
|
|
s_size = bytes(s[:4])
|
|
v_len = struct.unpack(b">I", s_size)[0]
|
|
if len(s) != (v_len + 4):
|
|
return None
|
|
if v_len == 0:
|
|
return 0
|
|
|
|
v_str = bytearray(s[4:])
|
|
neg = False
|
|
i = v_str[0]
|
|
if i & 0x80:
|
|
neg = True
|
|
i &= ~0x80
|
|
v_str[0] = i
|
|
|
|
v = bin2bn(v_str)
|
|
|
|
if neg:
|
|
return -v
|
|
return v
|
|
|
|
# bitcoin-specific little endian format, with implicit size
|
|
|
|
|
|
def mpi2vch(s):
|
|
r = s[4:] # strip size
|
|
# if r:
|
|
r = r[::-1] # reverse string, converting BE->LE
|
|
# else: r=b'\x00'
|
|
return r
|
|
|
|
|
|
def bn2vch(v):
|
|
return bytes(mpi2vch(bn2mpi(v)))
|
|
|
|
|
|
def vch2mpi(s):
|
|
r = struct.pack(b">I", len(s)) # size
|
|
r += s[::-1] # reverse string, converting LE->BE
|
|
return r
|
|
|
|
|
|
def vch2bn(s):
|
|
return mpi2bn(vch2mpi(s))
|
|
|
|
|
|
def i2b(i): return bn2vch(i)
|
|
|
|
|
|
def b2i(b): return vch2bn(b)
|
|
|
|
|
|
|
|
|
|
|