def derive_pubkey(message: str, signature: bytes) -> Tuple[bool, bytes]:
"""Derive a public key from a message and signature.
Return a tuple (is_verified, public_key). The public key, is returned
as a compressed key.
If public_key is a null bytestring, it means deriving the public
key from the signature failed. In this case is_verified is expected
to be always False.
If is_verified is True, it only means that this function was able to
derive a public key from the message and signature. This public key
still needs to be checked against another key or bitcoin address.
"""
h = bitcoin.Hash(bitcoin.msg_magic(message.encode("utf-8")))
try:
public_key_from_sig, compressed = bitcoin.pubkey_from_signature(
signature, h)
except Exception:
return False, b""
try:
is_verified = public_key_from_sig.verify_digest(
signature[1:], h, sigdecode=ecdsa.util.sigdecode_string)
except Exception:
is_verified = False
return is_verified, public_key_from_sig.to_string(encoding="compressed")
def update(self, window):
wallet = window.wallet
state = window.cosigner_pool_state
if not state:
self.print_error("No cosigner pool state object for window",
window.diagnostic_name())
return
listener = state.listener
state.keys = []
state.cosigner_list = []
for key, keystore in wallet.keystores.items():
xpub = keystore.get_master_public_key()
K = bitcoin.deserialize_xpub(xpub)[-1]
_hash = bh2u(bitcoin.Hash(K))
if not keystore.is_watching_only():
state.keys.append((key, _hash))
else:
state.cosigner_list.append((xpub, K, _hash))
listener.set_keyhashes([t[1] for t in state.keys])
if not listener.is_running():
self.print_error("Starting listener for", window.diagnostic_name())
listener.start()
def update(self, window):
wallet = window.wallet
if type(wallet) != Multisig_Wallet:
return
if self.listener is None:
self.print_error("starting listener")
self.listener = Listener(self)
self.listener.start()
elif self.listener:
self.print_error("shutting down listener")
self.listener.stop()
self.listener = None
self.keys = []
self.cosigner_list = []
for key, keystore in wallet.keystores.items():
xpub = keystore.get_master_public_key()
K = bitcoin.deserialize_xpub(xpub)[-1].encode('hex')
_hash = bitcoin.Hash(K).encode('hex')
if not keystore.is_watching_only():
self.keys.append((key, _hash, window))
else:
self.cosigner_list.append((window, xpub, K, _hash))
if self.listener:
self.listener.set_keyhashes([t[1] for t in self.keys])