# -*- encoding:utf-8 -*-
"""
Advanced signature manipulation. It is the recomended module to manually issue
signatures for ark blockchain and forks.
Variables:
- ``privateKey`` (:class:`str`): hexlified private key
- ``publicKey`` (:class:`str`): hexlified compressed - encoded public key
- ``message`` (:class:`str`): message to sign as string
"""
from dposlib.ark import secp256k1
from dposlib.ark.secp256k1 import ecdsa, schnorr
from dposlib.util.bin import unhexlify
[docs]class Signature(list):
r = property(
lambda cls: list.__getitem__(cls, 0),
None, None, "Signature part #1"
)
s = property(
lambda cls: list.__getitem__(cls, 1),
None, None, "Signature part #2"
)
der = property(
lambda cls: cls._der_getter(),
lambda cls, v: setattr(cls, "_der", v),
None, "Return DER encoded signature as bytes sequence"
)
raw = property(
lambda cls: cls._raw_getter(),
lambda cls, v: setattr(cls, "_raw", v),
None, "Return RAW Encode signature as bytes sequence"
)
def __init__(self, *rs):
list.__init__(self, [int(e) for e in rs])
def __repr__(self):
return "<secp256k1 signature:\n r:%064x\n s:%064x\n>" % tuple(self)
def _der_getter(cls):
if not hasattr(cls, "_der"):
setattr(cls, "_der", secp256k1.der_from_sig(*cls))
return getattr(cls, "_der")
def _raw_getter(cls):
if not hasattr(cls, "_raw"):
setattr(
cls, "_raw",
secp256k1.bytes_from_int(cls[0]) +
secp256k1.bytes_from_int(cls[1])
)
return getattr(cls, "_raw")
[docs] def ecdsa_verify(self, message, publicKey):
"""
Check if public key match message signature according to ``ECDSA``
scheme.
Args:
message (:class:`str`): message to verify
publicKey (:class:`str`): public key
Returns:
:class:`bool`: True if match
"""
return ecdsa.verify(
secp256k1.hash_sha256(message),
secp256k1.Point.decode(unhexlify(publicKey)).encode(),
self.der
)
[docs] def b410_schnorr_verify(self, message, publicKey):
"""
Check if public key match message signature according to
`Bcrypto 4.10 schnorr <https://github.com/bcoin-org/bcrypto/blob/v4.1.\
0/lib/js/schnorr.js>`_ scheme.
Args:
message (:class:`str`): message to verify
publicKey (:class:`str`): public key
Returns:
:class:`bool`: True if match
"""
return schnorr.bcrypto410_verify(
secp256k1.hash_sha256(message),
secp256k1.Point.decode(unhexlify(publicKey)).encode(),
self.raw
)
[docs] def schnorr_verify(self, message, publicKey):
"""
Check if public key match message signature according to
`BIP schnorr <https://github.com/sipa/bips/blob/bip-schnorr/bip-schnor\
r.mediawiki>`_ scheme.
Args:
message (:class:`str`): message to verify
publicKey (:class:`str`): public key
Returns:
:class:`bool`: True if match
"""
return schnorr.verify(
secp256k1.hash_sha256(message),
schnorr.bytes_from_point(
secp256k1.Point.decode(unhexlify(publicKey))
),
self.raw
)
[docs] @staticmethod
def from_raw(raw):
"""
Decode signature from RAW encoded bytes sequence.
Arguments:
raw (:class:`bytes`): encoded signature
Returns:
:class:`Signature`: signature
"""
length = len(raw) // 2
sig = Signature(
secp256k1.int_from_bytes(raw[:length]),
secp256k1.int_from_bytes(raw[length:]),
)
sig._raw = raw
return sig
[docs] @staticmethod
def from_der(der):
"""
Decode signature from DER encoded bytes sequence.
Arguments:
der (:class:`bytes`): encoded signature
Returns:
:class:`Signature`: signature
"""
sig = Signature(*secp256k1.sig_from_der(der))
sig._der = der
return sig
[docs] @staticmethod
def ecdsa_sign(message, privateKey, canonical=True):
"""
Generate message signature according to ``ECDSA`` scheme using a random
nonce.
Args:
message (:class:`str`): message to verify
privateKey (:class:`str`): private key
canonical (:class:`bool`): canonalize signature
Returns:
:class:`Signature`: signature
"""
return Signature.from_der(
ecdsa.sign(
secp256k1.hash_sha256(message), unhexlify(privateKey),
canonical=canonical
)
)
[docs] @staticmethod
def ecdsa_rfc6979_sign(message, privateKey, canonical=True):
"""
Generate message signature according to ``ECDSA`` scheme using a
deterministic nonce (RFC-6976).
Args:
message (:class:`str`): message to verify
privateKey (:class:`str`): private key
canonical (:class:`bool`): canonalize signature
Returns:
:class:`Signature`: signature
"""
return Signature.from_der(
ecdsa.rfc6979_sign(
secp256k1.hash_sha256(message), unhexlify(privateKey),
canonical=canonical
)
)
[docs] @staticmethod
def b410_schnorr_sign(message, privateKey):
"""
Generate message signature according to
`Bcrypto 4.10 schnorr <https://github.com/bcoin-org/bcrypto/blob/v4.1.\
0/lib/js/schnorr.js>`_ scheme.
Args:
message (:class:`str`): message to verify
privateKey (:class:`str`): private key
Returns:
:class:`Signature`: signature
"""
return Signature.from_raw(
schnorr.bcrypto410_sign(
secp256k1.hash_sha256(message), unhexlify(privateKey)
)
)
[docs] @staticmethod
def schnorr_sign(message, privateKey):
"""
Generate message signature according to
`BIP schnorr <https://github.com/sipa/bips/blob/bip-schnorr/bip-schnor\
r.mediawiki>`_ scheme.
Args:
message (:class:`str`): message to verify
privateKey (:class:`str`): private key
Returns:
:class:`Signature`: signature
"""
return Signature.from_raw(
schnorr.sign(
secp256k1.hash_sha256(message), unhexlify(privateKey)
)
)
