def compose_transaction(args, message_name, param_names): args = prepare_args(args, message_name) common_params = common_args(args) params = extract_args(args, param_names) params.update(common_params) # Get provided pubkeys from params. pubkeys = [] for address_name in ['source', 'destination']: if address_name in params: address = params[address_name] if not script.is_p2sh(address) and (script.is_multisig(address) or address_name != 'destination'): # We don’t need the pubkey for a mono‐sig destination. pubkeys += get_pubkeys(address) params['pubkey'] = pubkeys method = 'create_{}'.format(message_name) unsigned_tx_hex = util.api(method, params) # check_transaction(method, params, unsigned_tx_hex) return unsigned_tx_hex
def construct (db, tx_info, encoding='auto', fee_per_kb=config.DEFAULT_FEE_PER_KB, estimate_fee_per_kb=None, estimate_fee_per_kb_nblocks=config.ESTIMATE_FEE_NBLOCKS, regular_dust_size=config.DEFAULT_REGULAR_DUST_SIZE, multisig_dust_size=config.DEFAULT_MULTISIG_DUST_SIZE, op_return_value=config.DEFAULT_OP_RETURN_VALUE, exact_fee=None, fee_provided=0, provided_pubkeys=None, dust_return_pubkey=None, allow_unconfirmed_inputs=False, unspent_tx_hash=None, custom_inputs=None, disable_utxo_locks=False): if estimate_fee_per_kb is None: estimate_fee_per_kb = config.ESTIMATE_FEE_PER_KB global UTXO_LOCKS desired_encoding = encoding (source, destination_outputs, data) = tx_info if dust_return_pubkey: dust_return_pubkey = binascii.unhexlify(dust_return_pubkey) # Source. # If public key is necessary for construction of (unsigned) # transaction, use the public key provided, or find it from the # blockchain. if source: script.validate(source) source_is_p2sh = script.is_p2sh(source) # Sanity checks. if exact_fee and not isinstance(exact_fee, int): raise exceptions.TransactionError('Exact fees must be in satoshis.') if not isinstance(fee_provided, int): raise exceptions.TransactionError('Fee provided must be in satoshis.') if UTXO_LOCKS is None and config.UTXO_LOCKS_MAX_ADDRESSES > 0: # initialize if configured UTXO_LOCKS = util.DictCache(size=config.UTXO_LOCKS_MAX_ADDRESSES) '''Destinations''' # Destination outputs. # Replace multi‐sig addresses with multi‐sig pubkeys. Check that the # destination output isn’t a dust output. Set null values to dust size. destination_outputs_new = [] for (address, value) in destination_outputs: # Value. if script.is_multisig(address): dust_size = multisig_dust_size else: dust_size = regular_dust_size if value == None: value = dust_size elif value < dust_size: raise exceptions.TransactionError('Destination output is dust.') # Address. script.validate(address) if script.is_multisig(address): destination_outputs_new.append((backend.multisig_pubkeyhashes_to_pubkeys(address, provided_pubkeys), value)) else: destination_outputs_new.append((address, value)) destination_outputs = destination_outputs_new destination_btc_out = sum([value for address, value in destination_outputs]) '''Data''' if data: # Data encoding methods (choose and validate). if encoding == 'auto': if len(data) + len(config.PREFIX) <= config.OP_RETURN_MAX_SIZE: encoding = 'opreturn' else: encoding = 'multisig' elif encoding not in ('pubkeyhash', 'multisig', 'opreturn'): raise exceptions.TransactionError('Unknown encoding‐scheme.') if encoding == 'multisig': # dust_return_pubkey should be set or explicitly set to False to use the default configured for the node # the default for the node is optional so could fail if (source_is_p2sh and dust_return_pubkey is None) or (dust_return_pubkey is False and config.P2SH_DUST_RETURN_PUBKEY is None): raise exceptions.TransactionError("Can't use multisig encoding when source is P2SH and no dust_return_pubkey is provided.") elif dust_return_pubkey is False: dust_return_pubkey = binascii.unhexlify(config.P2SH_DUST_RETURN_PUBKEY) # Divide data into chunks. if encoding == 'pubkeyhash': # Prefix is also a suffix here. chunk_size = 20 - 1 - 8 elif encoding == 'multisig': # Two pubkeys, minus length byte, minus prefix, minus two nonces, # minus two sign bytes. chunk_size = (33 * 2) - 1 - 8 - 2 - 2 elif encoding == 'opreturn': chunk_size = config.OP_RETURN_MAX_SIZE if len(data) + len(config.PREFIX) > chunk_size: raise exceptions.TransactionError('One `OP_RETURN` output per transaction.') data_array = list(chunks(data, chunk_size)) # Data outputs. if encoding == 'multisig': data_value = multisig_dust_size elif encoding == 'opreturn': data_value = op_return_value else: # Pay‐to‐PubKeyHash, e.g. data_value = regular_dust_size data_output = (data_array, data_value) if not dust_return_pubkey: if encoding == 'multisig': dust_return_pubkey = get_dust_return_pubkey(source, provided_pubkeys, encoding) else: dust_return_pubkey = None else: data_array = [] data_output = None dust_return_pubkey = None data_btc_out = sum([data_value for data_chunk in data_array]) '''Inputs''' # Calculate collective size of outputs, for fee calculation. p2pkhsize = 25 + 9 if encoding == 'multisig': data_output_size = 81 # 71 for the data elif encoding == 'opreturn': data_output_size = 90 # 80 for the data else: data_output_size = p2pkhsize # Pay‐to‐PubKeyHash (25 for the data?) outputs_size = (p2pkhsize * len(destination_outputs)) + (len(data_array) * data_output_size) # Get inputs. multisig_inputs = not data use_inputs = custom_inputs # Array of UTXOs, as retrieved by listunspent function from bitcoind if custom_inputs is None: if unspent_tx_hash is not None: unspent = backend.get_unspent_txouts(source, unconfirmed=allow_unconfirmed_inputs, unspent_tx_hash=unspent_tx_hash, multisig_inputs=multisig_inputs) else: unspent = backend.get_unspent_txouts(source, unconfirmed=allow_unconfirmed_inputs, multisig_inputs=multisig_inputs) # filter out any locked UTXOs to prevent creating transactions that spend the same UTXO when they're created at the same time if UTXO_LOCKS is not None and source in UTXO_LOCKS: unspentkeys = {make_outkey(output) for output in unspent} filtered_unspentkeys = unspentkeys - UTXO_LOCKS[source].keys() unspent = [output for output in unspent if make_outkey(output) in filtered_unspentkeys] unspent = backend.sort_unspent_txouts(unspent) logger.debug('Sorted candidate UTXOs: {}'.format([print_coin(coin) for coin in unspent])) use_inputs = unspent # use backend estimated fee_per_kb if estimate_fee_per_kb: estimated_fee_per_kb = backend.fee_per_kb(estimate_fee_per_kb_nblocks) if estimated_fee_per_kb is not None: fee_per_kb = max(estimated_fee_per_kb, fee_per_kb) # never drop below the default fee_per_kb logger.debug('Fee/KB {:.8f}'.format(fee_per_kb / config.UNIT)) inputs = [] btc_in = 0 change_quantity = 0 sufficient_funds = False final_fee = fee_per_kb desired_input_count = 1 if encoding == 'multisig' and data_array and util.enabled('bytespersigop'): desired_input_count = len(data_array) * 2 for coin in use_inputs: logger.debug('New input: {}'.format(print_coin(coin))) inputs.append(coin) btc_in += round(coin['amount'] * config.UNIT) size = 181 * len(inputs) + outputs_size + 10 necessary_fee = int(size / 1000 * fee_per_kb) # If exact fee is specified, use that. Otherwise, calculate size of tx # and base fee on that (plus provide a minimum fee for selling BTC). if exact_fee: final_fee = exact_fee else: final_fee = max(fee_provided, necessary_fee) # Check if good. btc_out = destination_btc_out + data_btc_out change_quantity = btc_in - (btc_out + final_fee) logger.debug('Size: {} Fee: {:.8f} Change quantity: {:.8f} BTC'.format(size, final_fee / config.UNIT, change_quantity / config.UNIT)) # If change is necessary, must not be a dust output. if change_quantity == 0 or change_quantity >= regular_dust_size: sufficient_funds = True if len(inputs) >= desired_input_count: break if not sufficient_funds: # Approximate needed change, fee by with most recently calculated # quantities. btc_out = destination_btc_out + data_btc_out total_btc_out = btc_out + max(change_quantity, 0) + final_fee raise exceptions.BalanceError('Insufficient {} at address {}. (Need approximately {} {}.) To spend unconfirmed coins, use the flag `--unconfirmed`. (Unconfirmed coins cannot be spent from multi‐sig addresses.)'.format(config.BTC, source, total_btc_out / config.UNIT, config.BTC)) # Lock the source's inputs (UTXOs) chosen for this transaction if UTXO_LOCKS is not None and not disable_utxo_locks: if source not in UTXO_LOCKS: UTXO_LOCKS[source] = cachetools.TTLCache( UTXO_LOCKS_PER_ADDRESS_MAXSIZE, config.UTXO_LOCKS_MAX_AGE) for input in inputs: UTXO_LOCKS[source][make_outkey(input)] = input logger.debug("UTXO locks: Potentials ({}): {}, Used: {}, locked UTXOs: {}".format( len(unspent), [make_outkey(coin) for coin in unspent], [make_outkey(input) for input in inputs], list(UTXO_LOCKS[source].keys()))) '''Finish''' # Change output. if change_quantity: if script.is_multisig(source): change_address = backend.multisig_pubkeyhashes_to_pubkeys(source, provided_pubkeys) else: change_address = source change_output = (change_address, change_quantity) else: change_output = None # in bitcoin core v0.12.1 a -bytespersigop was added that messes with bare multisig transactions, # as a safeguard we fall back to pubkeyhash encoding when unsure # when len(inputs) > len(data_outputs) there's more bytes:sigops ratio and we can safely continue if encoding == 'multisig' and inputs and data_output and len(inputs) < len(data_array) * 2 and util.enabled('bytespersigop'): # if auto encoding we can do pubkeyhash encoding instead if desired_encoding == 'auto': return construct(db, tx_info, encoding='pubkeyhash', fee_per_kb=fee_per_kb, regular_dust_size=regular_dust_size, multisig_dust_size=multisig_dust_size, op_return_value=op_return_value, exact_fee=exact_fee, fee_provided=fee_provided, provided_pubkeys=provided_pubkeys, allow_unconfirmed_inputs=allow_unconfirmed_inputs, unspent_tx_hash=unspent_tx_hash, custom_inputs=custom_inputs) # otherwise raise exception else: raise exceptions.EncodingError("multisig will be rejected by Bitcoin Core >= v0.12.1, you should use `encoding=auto` or `encoding=pubkeyhash`") # Serialise inputs and outputs. unsigned_tx = serialise(encoding, inputs, destination_outputs, data_output, change_output, dust_return_pubkey=dust_return_pubkey) unsigned_tx_hex = binascii.hexlify(unsigned_tx).decode('utf-8') '''Sanity Check''' from counterpartylib.lib import blocks # Desired transaction info. (desired_source, desired_destination_outputs, desired_data) = tx_info desired_source = script.make_canonical(desired_source) desired_destination = script.make_canonical(desired_destination_outputs[0][0]) if desired_destination_outputs else '' # NOTE: Include change in destinations for BTC transactions. # if change_output and not desired_data and desired_destination != config.UNSPENDABLE: # if desired_destination == '': # desired_destination = desired_source # else: # desired_destination += '-{}'.format(desired_source) # NOTE if desired_data == None: desired_data = b'' # Parsed transaction info. try: parsed_source, parsed_destination, x, y, parsed_data = blocks._get_tx_info(unsigned_tx_hex) except exceptions.BTCOnlyError: # Skip BTC‐only transactions. return unsigned_tx_hex desired_source = script.make_canonical(desired_source) # Check desired info against parsed info. desired = (desired_source, desired_destination, desired_data) parsed = (parsed_source, parsed_destination, parsed_data) if desired != parsed: # Unlock (revert) UTXO locks if UTXO_LOCKS is not None: for input in inputs: UTXO_LOCKS[source].pop(make_outkey(input), None) raise exceptions.TransactionError('Constructed transaction does not parse correctly: {} ≠ {}'.format(desired, parsed)) return unsigned_tx_hex
def construct(db, tx_info, encoding='auto', fee_per_kb=config.DEFAULT_FEE_PER_KB, estimate_fee_per_kb=None, estimate_fee_per_kb_nblocks=config.ESTIMATE_FEE_NBLOCKS, regular_dust_size=config.DEFAULT_REGULAR_DUST_SIZE, multisig_dust_size=config.DEFAULT_MULTISIG_DUST_SIZE, op_return_value=config.DEFAULT_OP_RETURN_VALUE, exact_fee=None, fee_provided=0, provided_pubkeys=None, dust_return_pubkey=None, allow_unconfirmed_inputs=False, unspent_tx_hash=None, custom_inputs=None, disable_utxo_locks=False): if estimate_fee_per_kb is None: estimate_fee_per_kb = config.ESTIMATE_FEE_PER_KB global UTXO_LOCKS desired_encoding = encoding (source, destination_outputs, data) = tx_info if dust_return_pubkey: dust_return_pubkey = binascii.unhexlify(dust_return_pubkey) # Source. # If public key is necessary for construction of (unsigned) # transaction, use the public key provided, or find it from the # blockchain. if source: script.validate(source) source_is_p2sh = script.is_p2sh(source) # Sanity checks. if exact_fee and not isinstance(exact_fee, int): raise exceptions.TransactionError('Exact fees must be in satoshis.') if not isinstance(fee_provided, int): raise exceptions.TransactionError('Fee provided must be in satoshis.') if UTXO_LOCKS is None and config.UTXO_LOCKS_MAX_ADDRESSES > 0: # initialize if configured UTXO_LOCKS = util.DictCache(size=config.UTXO_LOCKS_MAX_ADDRESSES) '''Destinations''' # Destination outputs. # Replace multi‐sig addresses with multi‐sig pubkeys. Check that the # destination output isn’t a dust output. Set null values to dust size. destination_outputs_new = [] for (address, value) in destination_outputs: # Value. if script.is_multisig(address): dust_size = multisig_dust_size else: dust_size = regular_dust_size if value == None: value = dust_size elif value < dust_size: raise exceptions.TransactionError('Destination output is dust.') # Address. script.validate(address) if script.is_multisig(address): destination_outputs_new.append( (backend.multisig_pubkeyhashes_to_pubkeys( address, provided_pubkeys), value)) else: destination_outputs_new.append((address, value)) destination_outputs = destination_outputs_new destination_btc_out = sum( [value for address, value in destination_outputs]) '''Data''' if data: # Data encoding methods (choose and validate). if encoding == 'auto': if len(data) + len(config.PREFIX) <= config.OP_RETURN_MAX_SIZE: encoding = 'opreturn' else: encoding = 'multisig' elif encoding not in ('pubkeyhash', 'multisig', 'opreturn'): raise exceptions.TransactionError('Unknown encoding‐scheme.') if encoding == 'multisig': # dust_return_pubkey should be set or explicitly set to False to use the default configured for the node # the default for the node is optional so could fail if (source_is_p2sh and dust_return_pubkey is None) or ( dust_return_pubkey is False and config.P2SH_DUST_RETURN_PUBKEY is None): raise exceptions.TransactionError( "Can't use multisig encoding when source is P2SH and no dust_return_pubkey is provided." ) elif dust_return_pubkey is False: dust_return_pubkey = binascii.unhexlify( config.P2SH_DUST_RETURN_PUBKEY) # Divide data into chunks. if encoding == 'pubkeyhash': # Prefix is also a suffix here. chunk_size = 20 - 1 - 8 elif encoding == 'multisig': # Two pubkeys, minus length byte, minus prefix, minus two nonces, # minus two sign bytes. chunk_size = (33 * 2) - 1 - 8 - 2 - 2 elif encoding == 'opreturn': chunk_size = config.OP_RETURN_MAX_SIZE if len(data) + len(config.PREFIX) > chunk_size: raise exceptions.TransactionError( 'One `OP_RETURN` output per transaction.') data_array = list(chunks(data, chunk_size)) # Data outputs. if encoding == 'multisig': data_value = multisig_dust_size elif encoding == 'opreturn': data_value = op_return_value else: # Pay‐to‐PubKeyHash, e.g. data_value = regular_dust_size data_output = (data_array, data_value) if not dust_return_pubkey: if encoding == 'multisig': dust_return_pubkey = get_dust_return_pubkey( source, provided_pubkeys, encoding) else: dust_return_pubkey = None else: data_array = [] data_output = None dust_return_pubkey = None data_btc_out = sum([data_value for data_chunk in data_array]) '''Inputs''' # Calculate collective size of outputs, for fee calculation. p2pkhsize = 25 + 9 if encoding == 'multisig': data_output_size = 81 # 71 for the data elif encoding == 'opreturn': data_output_size = 90 # 80 for the data else: data_output_size = p2pkhsize # Pay‐to‐PubKeyHash (25 for the data?) outputs_size = (p2pkhsize * len(destination_outputs)) + (len(data_array) * data_output_size) # Get inputs. multisig_inputs = not data use_inputs = custom_inputs # Array of UTXOs, as retrieved by listunspent function from bitcoind if custom_inputs is None: if unspent_tx_hash is not None: unspent = backend.get_unspent_txouts( source, unconfirmed=allow_unconfirmed_inputs, unspent_tx_hash=unspent_tx_hash, multisig_inputs=multisig_inputs) else: unspent = backend.get_unspent_txouts( source, unconfirmed=allow_unconfirmed_inputs, multisig_inputs=multisig_inputs) # filter out any locked UTXOs to prevent creating transactions that spend the same UTXO when they're created at the same time if UTXO_LOCKS is not None and source in UTXO_LOCKS: unspentkeys = {make_outkey(output) for output in unspent} filtered_unspentkeys = unspentkeys - UTXO_LOCKS[source].keys() unspent = [ output for output in unspent if make_outkey(output) in filtered_unspentkeys ] unspent = backend.sort_unspent_txouts(unspent) logger.debug('Sorted candidate UTXOs: {}'.format( [print_coin(coin) for coin in unspent])) use_inputs = unspent # use backend estimated fee_per_kb if estimate_fee_per_kb: estimated_fee_per_kb = backend.fee_per_kb(estimate_fee_per_kb_nblocks) if estimated_fee_per_kb is not None: fee_per_kb = max( estimated_fee_per_kb, fee_per_kb) # never drop below the default fee_per_kb logger.debug('Fee/KB {:.8f}'.format(fee_per_kb / config.UNIT)) inputs = [] btc_in = 0 change_quantity = 0 sufficient_funds = False final_fee = fee_per_kb desired_input_count = 1 if encoding == 'multisig' and data_array and util.enabled('bytespersigop'): desired_input_count = len(data_array) * 2 for coin in use_inputs: logger.debug('New input: {}'.format(print_coin(coin))) inputs.append(coin) btc_in += round(coin['amount'] * config.UNIT) size = 181 * len(inputs) + outputs_size + 10 necessary_fee = int(size / 1000 * fee_per_kb) # If exact fee is specified, use that. Otherwise, calculate size of tx # and base fee on that (plus provide a minimum fee for selling BTC). if exact_fee: final_fee = exact_fee else: final_fee = max(fee_provided, necessary_fee) # Check if good. btc_out = destination_btc_out + data_btc_out change_quantity = btc_in - (btc_out + final_fee) logger.debug('Size: {} Fee: {:.8f} Change quantity: {:.8f} BTC'.format( size, final_fee / config.UNIT, change_quantity / config.UNIT)) # If change is necessary, must not be a dust output. if change_quantity == 0 or change_quantity >= regular_dust_size: sufficient_funds = True if len(inputs) >= desired_input_count: break if not sufficient_funds: # Approximate needed change, fee by with most recently calculated # quantities. btc_out = destination_btc_out + data_btc_out total_btc_out = btc_out + max(change_quantity, 0) + final_fee raise exceptions.BalanceError( 'Insufficient {} at address {}. (Need approximately {} {}.) To spend unconfirmed coins, use the flag `--unconfirmed`. (Unconfirmed coins cannot be spent from multi‐sig addresses.)' .format(config.BTC, source, total_btc_out / config.UNIT, config.BTC)) # Lock the source's inputs (UTXOs) chosen for this transaction if UTXO_LOCKS is not None and not disable_utxo_locks: if source not in UTXO_LOCKS: UTXO_LOCKS[source] = cachetools.TTLCache( UTXO_LOCKS_PER_ADDRESS_MAXSIZE, config.UTXO_LOCKS_MAX_AGE) for input in inputs: UTXO_LOCKS[source][make_outkey(input)] = input logger.debug( "UTXO locks: Potentials ({}): {}, Used: {}, locked UTXOs: {}". format(len(unspent), [make_outkey(coin) for coin in unspent], [make_outkey(input) for input in inputs], list(UTXO_LOCKS[source].keys()))) '''Finish''' # Change output. if change_quantity: if script.is_multisig(source): change_address = backend.multisig_pubkeyhashes_to_pubkeys( source, provided_pubkeys) else: change_address = source change_output = (change_address, change_quantity) else: change_output = None # in bitcoin core v0.12.1 a -bytespersigop was added that messes with bare multisig transactions, # as a safeguard we fall back to pubkeyhash encoding when unsure # when len(inputs) > len(data_outputs) there's more bytes:sigops ratio and we can safely continue if encoding == 'multisig' and inputs and data_output and len( inputs) < len(data_array) * 2 and util.enabled('bytespersigop'): # if auto encoding we can do pubkeyhash encoding instead if desired_encoding == 'auto': return construct(db, tx_info, encoding='pubkeyhash', fee_per_kb=fee_per_kb, regular_dust_size=regular_dust_size, multisig_dust_size=multisig_dust_size, op_return_value=op_return_value, exact_fee=exact_fee, fee_provided=fee_provided, provided_pubkeys=provided_pubkeys, allow_unconfirmed_inputs=allow_unconfirmed_inputs, unspent_tx_hash=unspent_tx_hash, custom_inputs=custom_inputs) # otherwise raise exception else: raise exceptions.EncodingError( "multisig will be rejected by Bitcoin Core >= v0.12.1, you should use `encoding=auto` or `encoding=pubkeyhash`" ) # Serialise inputs and outputs. unsigned_tx = serialise(encoding, inputs, destination_outputs, data_output, change_output, dust_return_pubkey=dust_return_pubkey) unsigned_tx_hex = binascii.hexlify(unsigned_tx).decode('utf-8') '''Sanity Check''' from counterpartylib.lib import blocks # Desired transaction info. (desired_source, desired_destination_outputs, desired_data) = tx_info desired_source = script.make_canonical(desired_source) desired_destination = script.make_canonical( desired_destination_outputs[0] [0]) if desired_destination_outputs else '' # NOTE: Include change in destinations for BTC transactions. # if change_output and not desired_data and desired_destination != config.UNSPENDABLE: # if desired_destination == '': # desired_destination = desired_source # else: # desired_destination += '-{}'.format(desired_source) # NOTE if desired_data == None: desired_data = b'' # Parsed transaction info. try: parsed_source, parsed_destination, x, y, parsed_data = blocks._get_tx_info( unsigned_tx_hex) except exceptions.BTCOnlyError: # Skip BTC‐only transactions. return unsigned_tx_hex desired_source = script.make_canonical(desired_source) # Check desired info against parsed info. desired = (desired_source, desired_destination, desired_data) parsed = (parsed_source, parsed_destination, parsed_data) if desired != parsed: # Unlock (revert) UTXO locks if UTXO_LOCKS is not None: for input in inputs: UTXO_LOCKS[source].pop(make_outkey(input), None) raise exceptions.TransactionError( 'Constructed transaction does not parse correctly: {} ≠ {}'.format( desired, parsed)) return unsigned_tx_hex
def construct( db, tx_info, encoding='auto', fee_per_kb=config.DEFAULT_FEE_PER_KB, estimate_fee_per_kb=None, estimate_fee_per_kb_conf_target=config.ESTIMATE_FEE_CONF_TARGET, estimate_fee_per_kb_mode=config.ESTIMATE_FEE_MODE, estimate_fee_per_kb_nblocks=config.ESTIMATE_FEE_CONF_TARGET, regular_dust_size=config.DEFAULT_REGULAR_DUST_SIZE, multisig_dust_size=config.DEFAULT_MULTISIG_DUST_SIZE, op_return_value=config.DEFAULT_OP_RETURN_VALUE, exact_fee=None, fee_provided=0, provided_pubkeys=None, dust_return_pubkey=None, allow_unconfirmed_inputs=False, unspent_tx_hash=None, custom_inputs=None, disable_utxo_locks=False, extended_tx_info=False, old_style_api=None, segwit=False, p2sh_source_multisig_pubkeys=None, p2sh_source_multisig_pubkeys_required=None, p2sh_pretx_txid=None, ): if estimate_fee_per_kb is None: estimate_fee_per_kb = config.ESTIMATE_FEE_PER_KB global UTXO_LOCKS, UTXO_P2SH_ENCODING_LOCKS # lazy assign from config, because when set as default it's evaluated before it's configured if old_style_api is None: old_style_api = config.OLD_STYLE_API (source, destination_outputs, data) = tx_info if dust_return_pubkey: dust_return_pubkey = binascii.unhexlify(dust_return_pubkey) if p2sh_source_multisig_pubkeys: p2sh_source_multisig_pubkeys = [ binascii.unhexlify(p) for p in p2sh_source_multisig_pubkeys ] # Source. # If public key is necessary for construction of (unsigned) # transaction, use the public key provided, or find it from the # blockchain. if source: script.validate(source) source_is_p2sh = script.is_p2sh(source) # Normalize source if script.is_multisig(source): source_address = backend.multisig_pubkeyhashes_to_pubkeys( source, provided_pubkeys) else: source_address = source # Sanity checks. if exact_fee and not isinstance(exact_fee, int): raise exceptions.TransactionError('Exact fees must be in satoshis.') if not isinstance(fee_provided, int): raise exceptions.TransactionError('Fee provided must be in satoshis.') '''Determine encoding method''' if data: desired_encoding = encoding # Data encoding methods (choose and validate). if desired_encoding == 'auto': if len(data) + len(config.PREFIX) <= config.OP_RETURN_MAX_SIZE: encoding = 'opreturn' else: encoding = 'p2sh' if not old_style_api and util.enabled( 'p2sh_encoding' ) else 'multisig' # p2sh is not possible with old_style_api elif desired_encoding == 'p2sh' and not util.enabled('p2sh_encoding'): raise exceptions.TransactionError('P2SH encoding not enabled yet') elif encoding not in ('pubkeyhash', 'multisig', 'opreturn', 'p2sh'): raise exceptions.TransactionError('Unknown encoding‐scheme.') else: # no data encoding = None '''Destinations''' # Destination outputs. # Replace multi‐sig addresses with multi‐sig pubkeys. Check that the # destination output isn’t a dust output. Set null values to dust size. destination_outputs_new = [] if encoding != 'p2sh': for (address, value) in destination_outputs: # Value. if script.is_multisig(address): dust_size = multisig_dust_size else: dust_size = regular_dust_size if value == None: value = dust_size elif value < dust_size: raise exceptions.TransactionError( 'Destination output is dust.') # Address. script.validate(address) if script.is_multisig(address): destination_outputs_new.append( (backend.multisig_pubkeyhashes_to_pubkeys( address, provided_pubkeys), value)) else: destination_outputs_new.append((address, value)) destination_outputs = destination_outputs_new destination_btc_out = sum( [value for address, value in destination_outputs]) '''Data''' if data: # @TODO: p2sh encoding require signable dust key if encoding == 'multisig': # dust_return_pubkey should be set or explicitly set to False to use the default configured for the node # the default for the node is optional so could fail if (source_is_p2sh and dust_return_pubkey is None) or ( dust_return_pubkey is False and config.P2SH_DUST_RETURN_PUBKEY is None): raise exceptions.TransactionError( "Can't use multisig encoding when source is P2SH and no dust_return_pubkey is provided." ) elif dust_return_pubkey is False: dust_return_pubkey = binascii.unhexlify( config.P2SH_DUST_RETURN_PUBKEY) # Divide data into chunks. if encoding == 'pubkeyhash': # Prefix is also a suffix here. chunk_size = 20 - 1 - 8 elif encoding == 'multisig': # Two pubkeys, minus length byte, minus prefix, minus two nonces, # minus two sign bytes. chunk_size = (33 * 2) - 1 - 8 - 2 - 2 elif encoding == 'p2sh': chunk_size = p2sh_encoding.maximum_data_chunk_size() elif encoding == 'opreturn': chunk_size = config.OP_RETURN_MAX_SIZE if len(data) + len(config.PREFIX) > chunk_size: raise exceptions.TransactionError( 'One `OP_RETURN` output per transaction.') data_array = list(chunks(data, chunk_size)) # Data outputs. if encoding == 'multisig': data_value = multisig_dust_size elif encoding == 'p2sh': data_value = 0 # this will be calculated later elif encoding == 'opreturn': data_value = op_return_value else: # Pay‐to‐PubKeyHash, e.g. data_value = regular_dust_size data_output = (data_array, data_value) if not dust_return_pubkey: if encoding == 'multisig' or encoding == 'p2sh' and not source_is_p2sh: dust_return_pubkey = get_dust_return_pubkey( source, provided_pubkeys, encoding) else: dust_return_pubkey = None else: data_value = 0 data_array = [] data_output = None dust_return_pubkey = None data_btc_out = data_value * len(data_array) logger.getChild('p2shdebug').debug( 'data_btc_out=%s (data_value=%d len(data_array)=%d)' % (data_btc_out, data_value, len(data_array))) '''Inputs''' btc_in = 0 final_fee = 0 # Calculate collective size of outputs, for fee calculation. p2pkhsize = 25 + 9 if encoding == 'multisig': data_output_size = 81 # 71 for the data elif encoding == 'opreturn': # prefix + data + 10 bytes script overhead data_output_size = len(config.PREFIX) + 10 if data is not None: data_output_size = data_output_size + len(data) else: data_output_size = p2pkhsize # Pay‐to‐PubKeyHash (25 for the data?) outputs_size = (p2pkhsize * len(destination_outputs)) + (len(data_array) * data_output_size) if encoding == 'p2sh': # calculate all the p2sh outputs size_for_fee, datatx_necessary_fee, data_value, data_btc_out = p2sh_encoding.calculate_outputs( destination_outputs, data_array, fee_per_kb) # replace the data value data_output = (data_array, data_value) else: sum_data_output_size = len(data_array) * data_output_size size_for_fee = ( (25 + 9) * len(destination_outputs)) + sum_data_output_size if not (encoding == 'p2sh' and p2sh_pretx_txid): inputs, change_quantity, n_btc_in, n_final_fee = construct_coin_selection( encoding, data_array, source, allow_unconfirmed_inputs, unspent_tx_hash, custom_inputs, fee_per_kb, estimate_fee_per_kb, estimate_fee_per_kb_nblocks, exact_fee, size_for_fee, fee_provided, destination_btc_out, data_btc_out, regular_dust_size, disable_utxo_locks) btc_in = n_btc_in final_fee = n_final_fee else: # when encoding is P2SH and the pretx txid is passed we can skip coinselection inputs, change_quantity = None, None '''Finish''' if change_quantity: change_output = (source_address, change_quantity) else: change_output = None unsigned_pretx_hex = None unsigned_tx_hex = None pretx_txid = None if encoding == 'p2sh': assert not (segwit and p2sh_pretx_txid ) # shouldn't do old style with segwit enabled if p2sh_pretx_txid: pretx_txid = p2sh_pretx_txid if isinstance( p2sh_pretx_txid, bytes) else binascii.unhexlify(p2sh_pretx_txid) unsigned_pretx = None else: destination_value_sum = sum( [value for (destination, value) in destination_outputs]) source_value = destination_value_sum if change_output: # add the difference between source and destination to the change change_value = change_output[1] + (destination_value_sum - source_value) change_output = (change_output[0], change_value) unsigned_pretx = serializer.serialise_p2sh_pretx( inputs, source=source_address, source_value=source_value, data_output=data_output, change_output=change_output, pubkey=dust_return_pubkey, multisig_pubkeys=p2sh_source_multisig_pubkeys, multisig_pubkeys_required=p2sh_source_multisig_pubkeys_required ) unsigned_pretx_hex = binascii.hexlify(unsigned_pretx).decode( 'utf-8') # with segwit we already know the txid and can return both if segwit: #pretx_txid = hashlib.sha256(unsigned_pretx).digest() # this should be segwit txid ptx = CTransaction.stream_deserialize( io.BytesIO(unsigned_pretx)) # could be a non-segwit tx anyways txid_ba = bytearray(ptx.GetTxid()) txid_ba.reverse() pretx_txid = bytes( txid_ba) # gonna leave the malleability problem to upstream logger.getChild('p2shdebug').debug('pretx_txid %s' % pretx_txid) print('pretx txid:', binascii.hexlify(pretx_txid)) if unsigned_pretx: # we set a long lock on this, don't want other TXs to spend from it UTXO_P2SH_ENCODING_LOCKS[make_outkey_vin(unsigned_pretx, 0)] = True # only generate the data TX if we have the pretx txId if pretx_txid: source_input = None if script.is_p2sh(source): source_input = select_any_coin_from_source(source) if not source_input: raise exceptions.TransactionError( 'Unable to select source input for p2sh source address' ) unsigned_datatx = serializer.serialise_p2sh_datatx( pretx_txid, source=source_address, source_input=source_input, destination_outputs=destination_outputs, data_output=data_output, pubkey=dust_return_pubkey, multisig_pubkeys=p2sh_source_multisig_pubkeys, multisig_pubkeys_required=p2sh_source_multisig_pubkeys_required ) unsigned_datatx_hex = binascii.hexlify(unsigned_datatx).decode( 'utf-8') # let the rest of the code work it's magic on the data tx unsigned_tx_hex = unsigned_datatx_hex else: # we're just gonna return the pretx, it doesn't require any of the further checks logger.warn('old_style_api = %s' % old_style_api) return return_result([unsigned_pretx_hex], old_style_api=old_style_api) else: # Serialise inputs and outputs. unsigned_tx = serializer.serialise( encoding, inputs, destination_outputs, data_output, change_output, dust_return_pubkey=dust_return_pubkey) unsigned_tx_hex = binascii.hexlify(unsigned_tx).decode('utf-8') '''Sanity Check''' # Desired transaction info. (desired_source, desired_destination_outputs, desired_data) = tx_info desired_source = script.make_canonical(desired_source) desired_destination = script.make_canonical( desired_destination_outputs[0] [0]) if desired_destination_outputs else '' # NOTE: Include change in destinations for BTC transactions. # if change_output and not desired_data and desired_destination != config.UNSPENDABLE: # if desired_destination == '': # desired_destination = desired_source # else: # desired_destination += '-{}'.format(desired_source) # NOTE if desired_data == None: desired_data = b'' # Parsed transaction info. try: if pretx_txid and unsigned_pretx: backend.cache_pretx(pretx_txid, unsigned_pretx) parsed_source, parsed_destination, x, y, parsed_data, extra = blocks._get_tx_info( unsigned_tx_hex, p2sh_is_segwit=script.is_bech32(desired_source)) if encoding == 'p2sh': # make_canonical can't determine the address, so we blindly change the desired to the parsed desired_source = parsed_source if pretx_txid and unsigned_pretx: backend.clear_pretx(pretx_txid) except exceptions.BTCOnlyError: # Skip BTC‐only transactions. if extended_tx_info: return { 'btc_in': btc_in, 'btc_out': destination_btc_out + data_btc_out, 'btc_change': change_quantity, 'btc_fee': final_fee, 'tx_hex': unsigned_tx_hex, } logger.getChild('p2shdebug').debug('BTC-ONLY') return return_result([unsigned_pretx_hex, unsigned_tx_hex], old_style_api=old_style_api) desired_source = script.make_canonical(desired_source) # Check desired info against parsed info. desired = (desired_source, desired_destination, desired_data) parsed = (parsed_source, parsed_destination, parsed_data) if desired != parsed: # Unlock (revert) UTXO locks if UTXO_LOCKS is not None and inputs: for input in inputs: UTXO_LOCKS[source].pop(make_outkey(input), None) raise exceptions.TransactionError( 'Constructed transaction does not parse correctly: {} ≠ {}'.format( desired, parsed)) if extended_tx_info: return { 'btc_in': btc_in, 'btc_out': destination_btc_out + data_btc_out, 'btc_change': change_quantity, 'btc_fee': final_fee, 'tx_hex': unsigned_tx_hex, } return return_result([unsigned_pretx_hex, unsigned_tx_hex], old_style_api=old_style_api)