def evaluate(self, z):
# create a copy as we may need to add to this list if we have a
# RedeemScript
commands = self.commands[:]
stack = []
altstack = []
while len(commands) > 0:
command = commands.pop(0)
if type(command) == int:
# do what the op code says
operation = op_function(command)
if command in (99, 100):
# op_if/op_notif require the commands array
if not operation(stack, commands):
print(f'bad op: {op_name(command)}')
return False
elif command in (107, 108):
# op_toaltstack/op_fromaltstack require the altstack
if not operation(stack, altstack):
print(f'bad op: {op_name(command)}')
return False
elif command in (172, 173, 174, 175):
# these are signing operations, they need a sig_hash
# to check against
if not operation(stack, z):
print(f'bad op: {op_name(command)}')
return False
else:
if not operation(stack):
print(f'bad op: {op_name(command)}')
return False
else:
# add the command to the stack
stack.append(command)
if len(stack) == 0:
return False
if stack.pop() == b'':
return False
return True
def evaluate(self, z):
# create a copy as we may need to add to this list if we have a
# RedeemScript
commands = self.commands[:]
stack = []
altstack = []
while len(commands) > 0:
command = commands.pop(0)
if type(command) == int:
# do what the op code says
operation = op_function(command)
if command in (99, 100):
# op_if/op_notif require the commands array
if not operation(stack, commands):
print(f'bad op: {op_name(command)}')
return False
elif command in (107, 108):
# op_toaltstack/op_fromaltstack require the altstack
if not operation(stack, altstack):
print(f'bad op: {op_name(command)}')
return False
elif command in (172, 173, 174, 175):
# these are signing operations, they need a sig_hash
# to check against
if not operation(stack, z):
print(f'bad op: {op_name(command)}')
return False
else:
if not operation(stack):
print(f'bad op: {op_name(command)}')
return False
else:
# add the command to the stack
stack.append(command)
# p2sh rule. if the next three commands are:
# OP_HASH160 <20 byte hash> OP_EQUAL this is the RedeemScript
# OP_HASH160 == 0xa9 and OP_EQUAL == 0x87
if len(commands) == 3 and commands[0] == 0xa9 \
and type(commands[1]) == bytes and len(commands[1]) == 20 \
and commands[2] == 0x87:
redeem_script = encode_varint(len(command)) + command
# we execute the next three op codes
commands.pop()
h160 = commands.pop()
commands.pop()
if not op_hash160(stack):
return False
stack.append(h160)
if not op_equal(stack):
return False
# final result should be a 1
if not op_verify(stack):
print('bad p2sh h160')
return False
# hashes match! now add the RedeemScript
stream = BytesIO(redeem_script)
commands.extend(Script.parse(stream).commands)
if len(stack) == 0:
return False
if stack.pop() == b'':
return False
return True