def get_dust_return_pubkey(db, source, provided_pubkeys, encoding):
"""Return the pubkey to which dust from data outputs will be sent.
This pubkey is used in multi-sig data outputs (as the only real pubkey) to
make those the outputs spendable. It is derived from the source address, so
that the dust is spendable by the creator of the transaction.
"""
# Get hex dust return pubkey.
if script.is_multisig(source):
_, self_pubkeys, _ = script.extract_array(
backend.multisig_pubkeyhashes_to_pubkeys(source, provided_pubkeys))
dust_return_pubkey_hex = self_pubkeys[0]
else:
cursor = db.cursor()
sql = '''SELECT pubkey FROM pubkeys WHERE address = ? LIMIT 1'''
pubkeys = list(cursor.execute(sql, (source, )))
if len(pubkeys) == 0:
raise UnknownPubKeyError(
'Public key was neither provided nor published in blockchain.')
else:
dust_return_pubkey_hex = pubkeys[0]['pubkey']
# Convert hex public key into the (binary) dust return pubkey.
try:
dust_return_pubkey = binascii.unhexlify(dust_return_pubkey_hex)
except binascii.Error:
raise script.InputError('Invalid public key.')
return dust_return_pubkey
def get_dust_return_pubkey(source, provided_pubkeys, encoding):
"""Return the pubkey to which dust from data outputs will be sent.
This pubkey is used in multi-sig data outputs (as the only real pubkey) to
make those the outputs spendable. It is derived from the source address, so
that the dust is spendable by the creator of the transaction.
"""
# Get hex dust return pubkey.
if script.is_multisig(source):
a, self_pubkeys, b = script.extract_array(backend.multisig_pubkeyhashes_to_pubkeys(source, provided_pubkeys))
dust_return_pubkey_hex = self_pubkeys[0]
else:
dust_return_pubkey_hex = backend.pubkeyhash_to_pubkey(source, provided_pubkeys)
# Convert hex public key into the (binary) dust return pubkey.
try:
dust_return_pubkey = binascii.unhexlify(dust_return_pubkey_hex)
except binascii.Error:
raise script.InputError('Invalid private key.')
return dust_return_pubkey
def get_dust_return_pubkey(source, provided_pubkeys, encoding):
"""Return the pubkey to which dust from data outputs will be sent.
This pubkey is used in multi-sig data outputs (as the only real pubkey) to
make those the outputs spendable. It is derived from the source address, so
that the dust is spendable by the creator of the transaction.
"""
# Get hex dust return pubkey.
if script.is_multisig(source):
a, self_pubkeys, b = script.extract_array(
backend.multisig_pubkeyhashes_to_pubkeys(source, provided_pubkeys))
dust_return_pubkey_hex = self_pubkeys[0]
else:
dust_return_pubkey_hex = backend.pubkeyhash_to_pubkey(
source, provided_pubkeys)
# Convert hex public key into the (binary) dust return pubkey.
try:
dust_return_pubkey = binascii.unhexlify(dust_return_pubkey_hex)
except binascii.Error:
raise script.InputError('Invalid private key.')
return dust_return_pubkey
def get_dust_return_pubkey(source, provided_pubkeys, encoding):
# Get `dust_return_pubkey`, if necessary.
if encoding in ('multisig', 'pubkeyhash'):
# Get hex dust return pubkey.
if script.is_multisig(source):
a, self_pubkeys, b = script.extract_array(
backend.multisig_pubkeyhashes_to_pubkeys(
source, provided_pubkeys))
dust_return_pubkey_hex = self_pubkeys[0]
else:
dust_return_pubkey_hex = backend.pubkeyhash_to_pubkey(
source, provided_pubkeys)
# Convert hex public key into the (binary) dust return pubkey.
try:
dust_return_pubkey = binascii.unhexlify(dust_return_pubkey_hex)
except binascii.Error:
raise script.InputError('Invalid private key.')
else:
dust_return_pubkey = None
return dust_return_pubkey
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)
def construct (db, tx_info, encoding='auto',
fee_per_kb=config.DEFAULT_FEE_PER_KB,
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,
allow_unconfirmed_inputs=False):
(source, destination_outputs, data) = tx_info
# 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.')
'''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'''
# Data encoding methods (choose and validate).
if data:
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.')
# Divide data into chunks.
if data:
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))
else:
data_array = []
# Data outputs.
if data:
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)
else:
data_output = None
data_btc_out = sum([data_value for data_chunk in data_array])
'''Inputs'''
# 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)
if encoding == 'multisig':
dust_return_pubkey = get_dust_return_pubkey(source, provided_pubkeys, encoding)
else:
dust_return_pubkey = None
# Calculate collective size of outputs, for fee calculation.
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 = 25 + 9 # Pay‐to‐PubKeyHash (25 for the data?)
outputs_size = ((25 + 9) * len(destination_outputs)) + (len(data_array) * data_output_size)
# Get inputs.
multisig_inputs = not data
unspent = backend.get_unspent_txouts(source, unconfirmed=allow_unconfirmed_inputs, multisig_inputs=multisig_inputs)
unspent = backend.sort_unspent_txouts(unspent)
logger.debug('Sorted UTXOs: {}'.format([print_coin(coin) for coin in unspent]))
inputs = []
btc_in = 0
change_quantity = 0
sufficient_funds = False
final_fee = fee_per_kb
for coin in unspent:
logger.debug('New input: {}'.format(print_coin(coin)))
inputs.append(coin)
btc_in += round(coin['amount'] * config.UNIT)
# 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:
size = 181 * len(inputs) + outputs_size + 10
necessary_fee = (int(size / 1000) + 1) * fee_per_kb
final_fee = max(fee_provided, necessary_fee)
assert final_fee >= 1 * fee_per_kb
# Check if good.
btc_out = destination_btc_out + data_btc_out
change_quantity = btc_in - (btc_out + final_fee)
logger.debug('Change quantity: {} BTC'.format(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
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))
'''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
# 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_info2(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:
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,
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,
allow_unconfirmed_inputs=False):
(source, destination_outputs, data) = tx_info
# 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.')
'''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'''
# Data encoding methods (choose and validate).
if data:
if encoding == 'auto':
if len(data) <= config.OP_RETURN_MAX_SIZE:
encoding = 'multisig' # BTCGuild isn’t mining `OP_RETURN`?!
else:
encoding = 'multisig'
elif encoding not in ('pubkeyhash', 'multisig', 'opreturn'):
raise exceptions.TransactionError('Unknown encoding‐scheme.')
# Divide data into chunks.
if data:
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) > chunk_size:
raise exceptions.TransactionError(
'One `OP_RETURN` output per transaction.')
data_array = list(chunks(data, chunk_size))
else:
data_array = []
# Data outputs.
if data:
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)
else:
data_output = None
data_btc_out = sum([data_value for data_chunk in data_array])
'''Inputs'''
# 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)
dust_return_pubkey = get_dust_return_pubkey(source, provided_pubkeys,
encoding)
# Calculate collective size of outputs, for fee calculation.
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 = 25 + 9 # Pay‐to‐PubKeyHash (25 for the data?)
outputs_size = ((25 + 9) * len(destination_outputs)) + (len(data_array) *
data_output_size)
# Get inputs.
unspent = backend.get_unspent_txouts(source)
unspent = backend.sort_unspent_txouts(unspent, allow_unconfirmed_inputs)
logger.debug('Sorted UTXOs: {}'.format(
[print_coin(coin) for coin in unspent]))
inputs = []
btc_in = 0
change_quantity = 0
sufficient_funds = False
final_fee = fee_per_kb
for coin in unspent:
logger.debug('New input: {}'.format(print_coin(coin)))
inputs.append(coin)
btc_in += round(coin['amount'] * config.UNIT)
# 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:
size = 181 * len(inputs) + outputs_size + 10
necessary_fee = (int(size / 1000) + 1) * fee_per_kb
final_fee = max(fee_provided, necessary_fee)
assert final_fee >= 1 * fee_per_kb
# Check if good.
btc_out = destination_btc_out + data_btc_out
change_quantity = btc_in - (btc_out + final_fee)
logger.debug('Change quantity: {} BTC'.format(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
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))
'''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
# 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_info2(
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.
if (desired_source, desired_destination,
desired_data) != (parsed_source, parsed_destination, parsed_data):
raise exceptions.TransactionError(
'constructed transaction does not parse correctly')
return unsigned_tx_hex
