def make_fully_valid(pubkey_start):
"""Take a too short data pubkey and make it look like a real pubkey.
Take an obfuscated chunk of data that is two bytes too short to be a pubkey and
add a sign byte to its beginning and a nonce byte to its end. Choose these
bytes so that the resulting sequence of bytes is a fully valid pubkey (i.e. on
the ECDSA curve). Find the correct bytes by guessing randomly until the check
passes. (In parsing, these two bytes are ignored.)
"""
assert type(pubkey_start) == bytes
assert len(pubkey_start) == 31 # One sign byte and one nonce byte required (for 33 bytes).
random_bytes = hashlib.sha256(pubkey_start).digest() # Deterministically generated, for unit tests.
sign = (random_bytes[0] & 0b1) + 2 # 0x02 or 0x03
nonce = initial_nonce = random_bytes[1]
pubkey = b''
while not script.is_fully_valid(pubkey):
# Increment nonce.
nonce += 1
assert nonce != initial_nonce
# Construct a possibly fully valid public key.
pubkey = bytes([sign]) + pubkey_start + bytes([nonce % 256])
assert len(pubkey) == 33
return pubkey
def compose_transaction(db, name, params,
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,
pubkey=None,
allow_unconfirmed_inputs=False,
fee=None,
fee_provided=0):
"""Create and return a transaction."""
# Get provided pubkeys.
if type(pubkey) == str:
provided_pubkeys = [pubkey]
elif type(pubkey) == list:
provided_pubkeys = pubkey
elif pubkey == None:
provided_pubkeys = []
else:
assert False
# Get additional pubkeys from `source` and `destination` params.
# Convert `source` and `destination` to pubkeyhash form.
for address_name in ['source', 'destination']:
if address_name in params:
address = params[address_name]
provided_pubkeys += script.extract_pubkeys(address)
params[address_name] = script.make_pubkeyhash(address)
# Check validity of collected pubkeys.
for pubkey in provided_pubkeys:
if not script.is_fully_valid(binascii.unhexlify(pubkey)):
raise script.AddressError('invalid public key: {}'.format(pubkey))
compose_method = sys.modules['shellpartylib.lib.messages.{}'.format(name)].compose
compose_params = inspect.getargspec(compose_method)[0]
missing_params = [p for p in compose_params if p not in params and p != 'db']
for param in missing_params:
params[param] = None
# try: # NOTE: For debugging, e.g. with `Invalid Params` error.
tx_info = compose_method(db, **params)
return transaction.construct(db, tx_info, encoding=encoding,
fee_per_kb=fee_per_kb,
regular_dust_size=regular_dust_size,
multisig_dust_size=multisig_dust_size,
op_return_value=op_return_value,
provided_pubkeys=provided_pubkeys,
allow_unconfirmed_inputs=allow_unconfirmed_inputs,
exact_fee=fee,
fee_provided=fee_provided)
def get_pubkey_monosig(pubkeyhash, pubkey_resolver=input_pubkey):
if wallet.is_valid(pubkeyhash):
# If in wallet, get from wallet.
logging.debug('Looking for public key for `{}` in wallet.'.format(pubkeyhash))
if wallet.is_mine(pubkeyhash):
pubkey = wallet.get_pubkey(pubkeyhash)
if pubkey:
return pubkey
logging.debug('Public key for `{}` not found in wallet.'.format(pubkeyhash))
# If in blockchain (and not in wallet), get from blockchain.
logging.debug('Looking for public key for `{}` in blockchain.'.format(pubkeyhash))
try:
pubkey = util.api('search_pubkey', {'pubkeyhash': pubkeyhash, 'provided_pubkeys': None})
except util.RPCError as e:
pubkey = None
if pubkey:
return pubkey
logging.debug('Public key for `{}` not found in blockchain.'.format(pubkeyhash))
# If not in wallet and not in blockchain, get from user.
answer = pubkey_resolver(pubkeyhash)
if not answer:
return None
# Public Key or Private Key?
is_fully_valid_pubkey = True
try:
is_fully_valid_pubkey = script.is_fully_valid(binascii.unhexlify(answer))
except binascii.Error:
is_fully_valid_pubkey = False
if is_fully_valid_pubkey:
logging.debug('Answer was a fully valid public key.')
pubkey = answer
else:
logging.debug('Answer was not a fully valid public key. Assuming answer was a private key.')
private_key = answer
try:
pubkey = script.private_key_to_public_key(private_key)
except script.AltcoinSupportError:
raise InputError('invalid private key')
if pubkeyhash != script.pubkey_to_pubkeyhash(binascii.unhexlify(bytes(pubkey, 'utf-8'))):
raise InputError('provided public or private key does not match the source address')
return pubkey
return None
