import six import logging from typing import List from collections import namedtuple from torba.basecoin import BaseCoin from torba.basescript import BaseInputScript, BaseOutputScript from torba.bcd_data_stream import BCDataStream from torba.hash import sha256 from torba.account import Account from torba.util import ReadOnlyList log = logging.getLogger() NULL_HASH = b'\x00'*32 class InputOutput(object): @property def size(self): """ Size of this input / output in bytes. """ stream = BCDataStream() self.serialize_to(stream) return len(stream.get_bytes()) def serialize_to(self, stream): raise NotImplemented class BaseInput(InputOutput): script_class = None NULL_SIGNATURE = b'\x00'*72 NULL_PUBLIC_KEY = b'\x00'*33 def __init__(self, output_or_txid_index, script, sequence=0xFFFFFFFF): if isinstance(output_or_txid_index, BaseOutput): self.output = output_or_txid_index # type: BaseOutput self.output_txid = self.output.transaction.hash self.output_index = self.output.index else: self.output = None # type: BaseOutput self.output_txid, self.output_index = output_or_txid_index self.sequence = sequence self.is_coinbase = self.output_txid == NULL_HASH self.coinbase = script if self.is_coinbase else None self.script = script if not self.is_coinbase else None # type: BaseInputScript def link_output(self, output): assert self.output is None assert self.output_txid == output.transaction.hash assert self.output_index == output.index self.output = output @classmethod def spend(cls, output): """ Create an input to spend the output.""" assert output.script.is_pay_pubkey_hash, 'Attempting to spend unsupported output.' script = cls.script_class.redeem_pubkey_hash(cls.NULL_SIGNATURE, cls.NULL_PUBLIC_KEY) return cls(output, script) @property def amount(self): """ Amount this input adds to the transaction. """ if self.output is None: raise ValueError('Cannot get input value without referenced output.') return self.output.amount @classmethod def deserialize_from(cls, stream): txid = stream.read(32) index = stream.read_uint32() script = stream.read_string() sequence = stream.read_uint32() return cls( (txid, index), cls.script_class(script) if not txid == NULL_HASH else script, sequence ) def serialize_to(self, stream, alternate_script=None): stream.write(self.output_txid) stream.write_uint32(self.output_index) if alternate_script is not None: stream.write_string(alternate_script) else: if self.is_coinbase: stream.write_string(self.coinbase) else: stream.write_string(self.script.source) stream.write_uint32(self.sequence) class BaseOutputAmountEstimator(object): __slots__ = 'coin', 'output', 'fee', 'effective_amount' def __init__(self, coin, txo): # type: (BaseCoin, BaseOutput) -> None self.coin = coin self.output = txo txi = coin.transaction_class.input_class.spend(txo) self.fee = coin.get_input_output_fee(txi) self.effective_amount = txo.amount - self.fee def __lt__(self, other): return self.effective_amount < other.effective_amount class BaseOutput(InputOutput): script_class = None estimator_class = BaseOutputAmountEstimator def __init__(self, amount, script): self.amount = amount # type: int self.script = script # type: BaseOutputScript self.transaction = None # type: BaseTransaction self.index = None # type: int def get_estimator(self, coin): return self.estimator_class(coin, self) @classmethod def pay_pubkey_hash(cls, amount, pubkey_hash): return cls(amount, cls.script_class.pay_pubkey_hash(pubkey_hash)) @classmethod def deserialize_from(cls, stream): return cls( amount=stream.read_uint64(), script=cls.script_class(stream.read_string()) ) def serialize_to(self, stream): stream.write_uint64(self.amount) stream.write_string(self.script.source) class BaseTransaction: input_class = None output_class = None def __init__(self, raw=None, version=1, locktime=0, height=None, is_saved=False): self._raw = raw self._hash = None self._id = None self.version = version # type: int self.locktime = locktime # type: int self.height = height # type: int self._inputs = [] # type: List[BaseInput] self._outputs = [] # type: List[BaseOutput] self.is_saved = is_saved # type: bool if raw is not None: self._deserialize() @property def id(self): if self._id is None: self._id = self.hash[::-1] return self._id @property def hash(self): if self._hash is None: self._hash = sha256(sha256(self.raw)) return self._hash @property def raw(self): if self._raw is None: self._raw = self._serialize() return self._raw def _reset(self): self._id = None self._hash = None self._raw = None @property def inputs(self): # type: () -> ReadOnlyList[BaseInput] return ReadOnlyList(self._inputs) @property def outputs(self): # type: () -> ReadOnlyList[BaseOutput] return ReadOnlyList(self._outputs) def add_inputs(self, inputs): self._inputs.extend(inputs) self._reset() return self def add_outputs(self, outputs): for txo in outputs: txo.transaction = self txo.index = len(self._outputs) self._outputs.append(txo) self._reset() return self @property def fee(self): """ Fee that will actually be paid.""" return self.input_sum - self.output_sum @property def size(self): """ Size in bytes of the entire transaction. """ return len(self.raw) @property def base_size(self): """ Size in bytes of transaction meta data and all outputs; without inputs. """ return len(self._serialize(with_inputs=False)) def _serialize(self, with_inputs=True): stream = BCDataStream() stream.write_uint32(self.version) if with_inputs: stream.write_compact_size(len(self._inputs)) for txin in self._inputs: txin.serialize_to(stream) stream.write_compact_size(len(self._outputs)) for txout in self._outputs: txout.serialize_to(stream) stream.write_uint32(self.locktime) return stream.get_bytes() def _serialize_for_signature(self, signing_input): stream = BCDataStream() stream.write_uint32(self.version) stream.write_compact_size(len(self._inputs)) for i, txin in enumerate(self._inputs): if signing_input == i: txin.serialize_to(stream, txin.output.script.source) else: txin.serialize_to(stream, b'') stream.write_compact_size(len(self._outputs)) for txout in self._outputs: txout.serialize_to(stream) stream.write_uint32(self.locktime) stream.write_uint32(1) # signature hash type: SIGHASH_ALL return stream.get_bytes() def _deserialize(self): if self._raw is not None: stream = BCDataStream(self._raw) self.version = stream.read_uint32() input_count = stream.read_compact_size() self.add_inputs([ self.input_class.deserialize_from(stream) for _ in range(input_count) ]) output_count = stream.read_compact_size() self.add_outputs([ self.output_class.deserialize_from(stream) for _ in range(output_count) ]) self.locktime = stream.read_uint32() def sign(self, account): # type: (Account) -> BaseTransaction for i, txi in enumerate(self._inputs): txo_script = txi.output.script if txo_script.is_pay_pubkey_hash: address = account.coin.hash160_to_address(txo_script.values['pubkey_hash']) private_key = account.get_private_key_for_address(address) tx = self._serialize_for_signature(i) txi.script.values['signature'] = private_key.sign(tx)+six.int2byte(1) txi.script.values['pubkey'] = private_key.public_key.pubkey_bytes txi.script.generate() self._reset() return self def sort(self): # See https://github.com/kristovatlas/rfc/blob/master/bips/bip-li01.mediawiki self._inputs.sort(key=lambda i: (i['prevout_hash'], i['prevout_n'])) self._outputs.sort(key=lambda o: (o[2], pay_script(o[0], o[1]))) @property def input_sum(self): return sum(i.amount for i in self._inputs) @property def output_sum(self): return sum(o.amount for o in self._outputs)