def get_pubkeyhash(scriptpubkey):
asm = script.get_asm(scriptpubkey)
if len(asm) != 5 or asm[0] != 'OP_DUP' or asm[1] != 'OP_HASH160' or asm[3] != 'OP_EQUALVERIFY' or asm[4] != 'OP_CHECKSIG':
return False
return asm[2]
def get_tx_info2(tx_hex, block_parser=None):
"""Get multisig transaction info.
The destinations, if they exists, always comes before the data output; the
change, if it exists, always comes after.
"""
# Decode transaction binary.
ctx = backend.deserialize(tx_hex)
def arc4_decrypt(cyphertext):
'''Un‐obfuscate. Initialise key once per attempt.'''
key = ARC4.new(ctx.vin[0].prevout.hash[::-1])
return key.decrypt(cyphertext)
def get_opreturn(asm):
if len(asm) == 2 and asm[0] == 'OP_RETURN':
pubkeyhash = asm[1]
if type(pubkeyhash) == bytes:
return pubkeyhash
raise DecodeError('invalid OP_RETURN')
def decode_opreturn(asm):
chunk = get_opreturn(asm)
chunk = arc4_decrypt(chunk)
if chunk[:len(config.PREFIX)] == config.PREFIX: # Data
destination, data = None, chunk[len(config.PREFIX):]
else:
raise DecodeError('unrecognised OP_RETURN output')
return destination, data
def decode_checksig(asm):
pubkeyhash = script.get_checksig(asm)
chunk = arc4_decrypt(pubkeyhash)
if chunk[1:len(config.PREFIX) + 1] == config.PREFIX: # Data
# Padding byte in each output (instead of just in the last one) so that encoding methods may be mixed. Also, it’s just not very much data.
chunk_length = chunk[0]
chunk = chunk[1:chunk_length + 1]
destination, data = None, chunk[len(config.PREFIX):]
else: # Destination
pubkeyhash = binascii.hexlify(pubkeyhash).decode('utf-8')
destination, data = script.base58_check_encode(pubkeyhash, config.ADDRESSVERSION), None
return destination, data
def decode_checkmultisig(asm):
pubkeys, signatures_required = script.get_checkmultisig(asm)
chunk = b''
for pubkey in pubkeys[:-1]: # (No data in last pubkey.)
chunk += pubkey[1:-1] # Skip sign byte and nonce byte.
chunk = arc4_decrypt(chunk)
if chunk[1:len(config.PREFIX) + 1] == config.PREFIX: # Data
# Padding byte in each output (instead of just in the last one) so that encoding methods may be mixed. Also, it’s just not very much data.
chunk_length = chunk[0]
chunk = chunk[1:chunk_length + 1]
destination, data = None, chunk[len(config.PREFIX):]
else: # Destination
pubkeyhashes = [script.pubkey_to_pubkeyhash(pubkey) for pubkey in pubkeys]
destination, data = script.construct_array(signatures_required, pubkeyhashes, len(pubkeyhashes)), None
return destination, data
# Ignore coinbase transactions.
if ctx.is_coinbase():
raise DecodeError('coinbase transaction')
# Get destinations and data outputs.
destinations, shell_amount, fee, data = [], 0, 0, b''
for vout in ctx.vout:
# Fee is the input values minus output values.
output_value = vout.nValue
fee -= output_value
# Ignore transactions with invalid script.
try:
asm = script.get_asm(vout.scriptPubKey)
except CScriptInvalidError as e:
raise DecodeError(e)
if asm[0] == 'OP_RETURN':
new_destination, new_data = decode_opreturn(asm)
elif asm[-1] == 'OP_CHECKSIG':
new_destination, new_data = decode_checksig(asm)
elif asm[-1] == 'OP_CHECKMULTISIG':
new_destination, new_data = decode_checkmultisig(asm)
else:
raise DecodeError('unrecognised output type')
assert not (new_destination and new_data)
assert new_destination != None or new_data != None # `decode_*()` should never return `None, None`.
if util.enabled('null_data_check'):
if new_data == []:
raise DecodeError('new destination is `None`')
# All destinations come before all data.
if not data and not new_data and destinations != [config.UNSPENDABLE,]:
destinations.append(new_destination)
shell_amount += output_value
else:
if new_destination: # Change.
break
else: # Data.
data += new_data
# Only look for source if data were found or destination is `UNSPENDABLE`,
# for speed.
if not data and destinations != [config.UNSPENDABLE,]:
raise SCHOnlyError('no data and not unspendable')
# Collect all (unique) source addresses.
sources = []
for vin in ctx.vin[:]: # Loop through inputs.
# Get the full transaction data for this input transaction.
if block_parser:
vin_tx = block_parser.read_raw_transaction(ib2h(vin.prevout.hash))
vin_ctx = backend.deserialize(vin_tx['__data__'])
else:
vin_tx = backend.getrawtransaction(ib2h(vin.prevout.hash))
vin_ctx = backend.deserialize(vin_tx)
vout = vin_ctx.vout[vin.prevout.n]
fee += vout.nValue
asm = script.get_asm(vout.scriptPubKey)
if asm[-1] == 'OP_CHECKSIG':
new_source, new_data = decode_checksig(asm)
if new_data or not new_source:
raise DecodeError('data in source')
elif asm[-1] == 'OP_CHECKMULTISIG':
new_source, new_data = decode_checkmultisig(asm)
if new_data or not new_source:
raise DecodeError('data in source')
else:
raise DecodeError('unrecognised source type')
# Collect unique sources.
if new_source not in sources:
sources.append(new_source)
sources = '-'.join(sources)
destinations = '-'.join(destinations)
return sources, destinations, shell_amount, round(fee), data
def get_tx_info1(tx_hex, block_index, block_parser=None):
"""Get singlesig transaction info.
The destination, if it exists, always comes before the data output; the
change, if it exists, always comes after.
"""
ctx = backend.deserialize(tx_hex)
def get_pubkeyhash(scriptpubkey):
asm = script.get_asm(scriptpubkey)
if len(asm) != 5 or asm[0] != 'OP_DUP' or asm[1] != 'OP_HASH160' or asm[3] != 'OP_EQUALVERIFY' or asm[4] != 'OP_CHECKSIG':
return False
return asm[2]
def get_address(scriptpubkey):
pubkeyhash = get_pubkeyhash(scriptpubkey)
if not pubkeyhash:
return False
pubkeyhash = binascii.hexlify(pubkeyhash).decode('utf-8')
address = script.base58_check_encode(pubkeyhash, config.ADDRESSVERSION)
# Test decoding of address.
if address != config.UNSPENDABLE and binascii.unhexlify(bytes(pubkeyhash, 'utf-8')) != script.base58_check_decode(address, config.ADDRESSVERSION):
return False
return address
# Fee is the input values minus output values.
fee = 0
# Get destination output and data output.
destination, shell_amount, data = None, None, b''
pubkeyhash_encoding = False
for vout in ctx.vout:
fee -= vout.nValue
# Sum data chunks to get data. (Can mix OP_RETURN and multi-sig.)
asm = script.get_asm(vout.scriptPubKey)
if len(asm) == 2 and asm[0] == 'OP_RETURN': # OP_RETURN
if type(asm[1]) != bytes:
continue
data_chunk = asm[1]
data += data_chunk
elif len(asm) == 5 and asm[0] == 1 and asm[3] == 2 and asm[4] == 'OP_CHECKMULTISIG': # Multi-sig
if type(asm[2]) != bytes:
continue
data_pubkey = asm[2]
data_chunk_length = data_pubkey[0] # No ord() necessary.
data_chunk = data_pubkey[1:data_chunk_length + 1]
data += data_chunk
elif len(asm) == 5 and (block_index >= 293000 or config.TESTNET): # Protocol change.
# Be strict.
pubkeyhash = get_pubkeyhash(vout.scriptPubKey)
if not pubkeyhash:
continue
if ctx.is_coinbase():
raise DecodeError('coinbase transaction')
obj1 = ARC4.new(ctx.vin[0].prevout.hash[::-1])
data_pubkey = obj1.decrypt(pubkeyhash)
if data_pubkey[1:9] == config.PREFIX or pubkeyhash_encoding:
pubkeyhash_encoding = True
data_chunk_length = data_pubkey[0] # No ord() necessary.
data_chunk = data_pubkey[1:data_chunk_length + 1]
if data_chunk[-8:] == config.PREFIX:
data += data_chunk[:-8]
break
else:
data += data_chunk
# Destination is the first output before the data.
if not destination and not shell_amount and not data:
address = get_address(vout.scriptPubKey)
if address:
destination = address
shell_amount = vout.nValue
# Check for, and strip away, prefix (except for burns).
if destination == config.UNSPENDABLE:
pass
elif data[:len(config.PREFIX)] == config.PREFIX:
data = data[len(config.PREFIX):]
else:
raise DecodeError('no prefix')
# Only look for source if data were found or destination is UNSPENDABLE, for speed.
if not data and destination != config.UNSPENDABLE:
raise SCHOnlyError('no data and not unspendable')
# Collect all possible source addresses; ignore coinbase transactions and anything but the simplest Pay‐to‐PubkeyHash inputs.
source_list = []
for vin in ctx.vin[:]: # Loop through input transactions.
if vin.prevout.is_null():
raise DecodeError('coinbase transaction')
# Get the full transaction data for this input transaction.
if block_parser:
vin_tx = block_parser.read_raw_transaction(ib2h(vin.prevout.hash))
vin_ctx = backend.deserialize(vin_tx['__data__'])
else:
vin_tx = backend.getrawtransaction(ib2h(vin.prevout.hash))
vin_ctx = backend.deserialize(vin_tx)
vout = vin_ctx.vout[vin.prevout.n]
fee += vout.nValue
address = get_address(vout.scriptPubKey)
if not address:
raise DecodeError('invalid scriptpubkey')
else:
source_list.append(address)
# Require that all possible source addresses be the same.
if all(x == source_list[0] for x in source_list):
source = source_list[0]
else:
source = None
return source, destination, shell_amount, fee, data