ranchimallflo-api/py3.7/lib/python3.7/site-packages/secp256k1/__init__.py
2019-06-09 17:28:47 +05:30

623 lines
21 KiB
Python

import os
import hashlib
import binascii
from ._libsecp256k1 import ffi, lib
EC_COMPRESSED = lib.SECP256K1_EC_COMPRESSED
EC_UNCOMPRESSED = lib.SECP256K1_EC_UNCOMPRESSED
FLAG_SIGN = lib.SECP256K1_CONTEXT_SIGN
FLAG_VERIFY = lib.SECP256K1_CONTEXT_VERIFY
ALL_FLAGS = FLAG_SIGN | FLAG_VERIFY
NO_FLAGS = lib.SECP256K1_CONTEXT_NONE
HAS_RECOVERABLE = hasattr(lib, 'secp256k1_ecdsa_sign_recoverable')
HAS_SCHNORR = hasattr(lib, 'secp256k1_schnorr_sign')
HAS_ECDH = hasattr(lib, 'secp256k1_ecdh')
class Base(object):
def __init__(self, ctx, flags):
self._destroy = None
if ctx is None:
assert flags in (NO_FLAGS, FLAG_SIGN, FLAG_VERIFY, ALL_FLAGS)
ctx = lib.secp256k1_context_create(flags)
self._destroy = lib.secp256k1_context_destroy
self.flags = flags
self.ctx = ctx
def __del__(self):
if not hasattr(self, '_destroy'):
return
if self._destroy and self.ctx:
self._destroy(self.ctx)
self.ctx = None
class ECDSA: # Use as a mixin; instance.ctx is assumed to exist.
def ecdsa_serialize(self, raw_sig):
len_sig = 74
output = ffi.new('unsigned char[%d]' % len_sig)
outputlen = ffi.new('size_t *', len_sig)
res = lib.secp256k1_ecdsa_signature_serialize_der(
self.ctx, output, outputlen, raw_sig)
assert res == 1
return bytes(ffi.buffer(output, outputlen[0]))
def ecdsa_deserialize(self, ser_sig):
raw_sig = ffi.new('secp256k1_ecdsa_signature *')
res = lib.secp256k1_ecdsa_signature_parse_der(
self.ctx, raw_sig, ser_sig, len(ser_sig))
assert res == 1
return raw_sig
def ecdsa_serialize_compact(self, raw_sig):
len_sig = 64
output = ffi.new('unsigned char[%d]' % len_sig)
res = lib.secp256k1_ecdsa_signature_serialize_compact(
self.ctx, output, raw_sig)
assert res == 1
return bytes(ffi.buffer(output, len_sig))
def ecdsa_deserialize_compact(self, ser_sig):
if len(ser_sig) != 64:
raise Exception("invalid signature length")
raw_sig = ffi.new('secp256k1_ecdsa_signature *')
res = lib.secp256k1_ecdsa_signature_parse_compact(
self.ctx, raw_sig, ser_sig)
assert res == 1
return raw_sig
def ecdsa_signature_normalize(self, raw_sig, check_only=False):
"""
Check and optionally convert a signature to a normalized lower-S form.
If check_only is True then the normalized signature is not returned.
This function always return a tuple containing a boolean (True if
not previously normalized or False if signature was already
normalized), and the normalized signature. When check_only is True,
the normalized signature returned is always None.
"""
if check_only:
sigout = ffi.NULL
else:
sigout = ffi.new('secp256k1_ecdsa_signature *')
result = lib.secp256k1_ecdsa_signature_normalize(
self.ctx, sigout, raw_sig)
return (bool(result), sigout if sigout != ffi.NULL else None)
def ecdsa_recover(self, msg, recover_sig, raw=False, digest=hashlib.sha256):
if not HAS_RECOVERABLE:
raise Exception("secp256k1_recovery not enabled")
if self.flags & ALL_FLAGS != ALL_FLAGS:
raise Exception("instance not configured for ecdsa recover")
msg32 = _hash32(msg, raw, digest)
pubkey = ffi.new('secp256k1_pubkey *')
recovered = lib.secp256k1_ecdsa_recover(
self.ctx, pubkey, recover_sig, msg32)
if recovered:
return pubkey
raise Exception('failed to recover ECDSA public key')
def ecdsa_recoverable_serialize(self, recover_sig):
if not HAS_RECOVERABLE:
raise Exception("secp256k1_recovery not enabled")
outputlen = 64
output = ffi.new('unsigned char[%d]' % outputlen)
recid = ffi.new('int *')
lib.secp256k1_ecdsa_recoverable_signature_serialize_compact(
self.ctx, output, recid, recover_sig)
return bytes(ffi.buffer(output, outputlen)), recid[0]
def ecdsa_recoverable_deserialize(self, ser_sig, rec_id):
if not HAS_RECOVERABLE:
raise Exception("secp256k1_recovery not enabled")
if rec_id < 0 or rec_id > 3:
raise Exception("invalid rec_id")
if len(ser_sig) != 64:
raise Exception("invalid signature length")
recover_sig = ffi.new('secp256k1_ecdsa_recoverable_signature *')
parsed = lib.secp256k1_ecdsa_recoverable_signature_parse_compact(
self.ctx, recover_sig, ser_sig, rec_id)
if parsed:
return recover_sig
else:
raise Exception('failed to parse ECDSA compact sig')
def ecdsa_recoverable_convert(self, recover_sig):
if not HAS_RECOVERABLE:
raise Exception("secp256k1_recovery not enabled")
normal_sig = ffi.new('secp256k1_ecdsa_signature *')
lib.secp256k1_ecdsa_recoverable_signature_convert(
self.ctx, normal_sig, recover_sig)
return normal_sig
class Schnorr: # Use as a mixin; instance.ctx is assumed to exist.
def schnorr_recover(self, msg, schnorr_sig, raw=False,
digest=hashlib.sha256):
if not HAS_SCHNORR:
raise Exception("secp256k1_schnorr not enabled")
if self.flags & FLAG_VERIFY != FLAG_VERIFY:
raise Exception("instance not configured for sig verification")
msg32 = _hash32(msg, raw, digest)
pubkey = ffi.new('secp256k1_pubkey *')
recovered = lib.secp256k1_schnorr_recover(
self.ctx, pubkey, schnorr_sig, msg32)
if recovered:
return pubkey
raise Exception('failed to recover public key')
def schnorr_partial_combine(self, schnorr_sigs):
"""Combine multiple Schnorr partial signatures."""
if not HAS_SCHNORR:
raise Exception("secp256k1_schnorr not enabled")
assert len(schnorr_sigs) > 0
sig64 = ffi.new('char [64]')
sig64sin = []
for sig in schnorr_sigs:
if not isinstance(sig, bytes):
raise TypeError('expected bytes, got {}'.format(type(sig)))
if len(sig) != 64:
raise Exception('invalid signature length')
sig64sin.append(ffi.new('char []', sig))
res = lib.secp256k1_schnorr_partial_combine(
self.ctx, sig64, sig64sin, len(sig64sin))
if res <= 0:
raise Exception('failed to combine signatures ({})'.format(res))
return bytes(ffi.buffer(sig64, 64))
class PublicKey(Base, ECDSA, Schnorr):
def __init__(self, pubkey=None, raw=False, flags=FLAG_VERIFY, ctx=None):
Base.__init__(self, ctx, flags)
if pubkey is not None:
if raw:
if not isinstance(pubkey, bytes):
raise TypeError('raw pubkey must be bytes')
self.public_key = self.deserialize(pubkey)
else:
if not isinstance(pubkey, ffi.CData):
raise TypeError('pubkey must be an internal object')
assert ffi.typeof(pubkey) is ffi.typeof('secp256k1_pubkey *')
self.public_key = pubkey
else:
self.public_key = None
def serialize(self, compressed=True):
assert self.public_key, "No public key defined"
len_compressed = 33 if compressed else 65
res_compressed = ffi.new('char [%d]' % len_compressed)
outlen = ffi.new('size_t *', len_compressed)
compflag = EC_COMPRESSED if compressed else EC_UNCOMPRESSED
serialized = lib.secp256k1_ec_pubkey_serialize(
self.ctx, res_compressed, outlen, self.public_key, compflag)
assert serialized == 1
return bytes(ffi.buffer(res_compressed, len_compressed))
def deserialize(self, pubkey_ser):
if len(pubkey_ser) not in (33, 65):
raise Exception("unknown public key size (expected 33 or 65)")
pubkey = ffi.new('secp256k1_pubkey *')
res = lib.secp256k1_ec_pubkey_parse(
self.ctx, pubkey, pubkey_ser, len(pubkey_ser))
if not res:
raise Exception("invalid public key")
self.public_key = pubkey
return pubkey
def combine(self, pubkeys):
"""Add a number of public keys together."""
assert len(pubkeys) > 0
outpub = ffi.new('secp256k1_pubkey *')
for item in pubkeys:
assert ffi.typeof(item) is ffi.typeof('secp256k1_pubkey *')
res = lib.secp256k1_ec_pubkey_combine(
self.ctx, outpub, pubkeys, len(pubkeys))
if not res:
raise Exception('failed to combine public keys')
self.public_key = outpub
return outpub
def tweak_add(self, scalar):
"""
Tweak the current public key by adding a 32 byte scalar times
the generator to it and return a new PublicKey instance.
"""
return _tweak_public(self, lib.secp256k1_ec_pubkey_tweak_add, scalar)
def tweak_mul(self, scalar):
"""
Tweak the current public key by multiplying it by a 32 byte scalar
and return a new PublicKey instance.
"""
return _tweak_public(self, lib.secp256k1_ec_pubkey_tweak_mul, scalar)
def ecdsa_verify(self, msg, raw_sig, raw=False, digest=hashlib.sha256):
assert self.public_key, "No public key defined"
if self.flags & FLAG_VERIFY != FLAG_VERIFY:
raise Exception("instance not configured for sig verification")
msg32 = _hash32(msg, raw, digest)
verified = lib.secp256k1_ecdsa_verify(
self.ctx, raw_sig, msg32, self.public_key)
return bool(verified)
def schnorr_verify(self, msg, schnorr_sig, raw=False,
digest=hashlib.sha256):
assert self.public_key, "No public key defined"
if not HAS_SCHNORR:
raise Exception("secp256k1_schnorr not enabled")
if self.flags & FLAG_VERIFY != FLAG_VERIFY:
raise Exception("instance not configured for sig verification")
msg32 = _hash32(msg, raw, digest)
verified = lib.secp256k1_schnorr_verify(
self.ctx, schnorr_sig, msg32, self.public_key)
return bool(verified)
def ecdh(self, scalar):
assert self.public_key, "No public key defined"
if not HAS_ECDH:
raise Exception("secp256k1_ecdh not enabled")
if not isinstance(scalar, bytes) or len(scalar) != 32:
raise TypeError('scalar must be composed of 32 bytes')
result = ffi.new('char [32]')
res = lib.secp256k1_ecdh(self.ctx, result, self.public_key, scalar)
if not res:
raise Exception('invalid scalar ({})'.format(res))
return bytes(ffi.buffer(result, 32))
class PrivateKey(Base, ECDSA, Schnorr):
def __init__(self, privkey=None, raw=True, flags=ALL_FLAGS, ctx=None):
assert flags in (ALL_FLAGS, FLAG_SIGN)
Base.__init__(self, ctx, flags)
self.pubkey = None
self.private_key = None
if privkey is None:
self.set_raw_privkey(_gen_private_key())
else:
if raw:
if not isinstance(privkey, bytes) or len(privkey) != 32:
raise TypeError('privkey must be composed of 32 bytes')
self.set_raw_privkey(privkey)
else:
self.deserialize(privkey)
def _update_public_key(self):
public_key = self._gen_public_key(self.private_key)
self.pubkey = PublicKey(
public_key, raw=False, ctx=self.ctx, flags=self.flags)
def set_raw_privkey(self, privkey):
if not lib.secp256k1_ec_seckey_verify(self.ctx, privkey):
raise Exception("invalid private key")
self.private_key = privkey
self._update_public_key()
def serialize(self):
hexkey = binascii.hexlify(self.private_key)
return hexkey.decode('utf8')
def deserialize(self, privkey_ser):
if len(privkey_ser) != 64:
raise Exception("invalid private key")
rawkey = binascii.unhexlify(privkey_ser)
self.set_raw_privkey(rawkey)
return self.private_key
def _gen_public_key(self, privkey):
pubkey_ptr = ffi.new('secp256k1_pubkey *')
created = lib.secp256k1_ec_pubkey_create(self.ctx, pubkey_ptr, privkey)
assert created == 1
return pubkey_ptr
def tweak_add(self, scalar):
"""
Tweak the current private key by adding a 32 byte scalar
to it and return a new raw private key composed of 32 bytes.
"""
return _tweak_private(self, lib.secp256k1_ec_privkey_tweak_add, scalar)
def tweak_mul(self, scalar):
"""
Tweak the current private key by multiplying it by a 32 byte scalar
and return a new raw private key composed of 32 bytes.
"""
return _tweak_private(self, lib.secp256k1_ec_privkey_tweak_mul, scalar)
def ecdsa_sign(self, msg, raw=False, digest=hashlib.sha256, custom_nonce=None):
msg32 = _hash32(msg, raw, digest)
raw_sig = ffi.new('secp256k1_ecdsa_signature *')
nonce_fn = ffi.NULL
nonce_data = ffi.NULL
if custom_nonce:
nonce_fn, nonce_data = custom_nonce
signed = lib.secp256k1_ecdsa_sign(
self.ctx, raw_sig, msg32, self.private_key, nonce_fn, nonce_data)
assert signed == 1
return raw_sig
def ecdsa_sign_recoverable(self, msg, raw=False, digest=hashlib.sha256):
if not HAS_RECOVERABLE:
raise Exception("secp256k1_recovery not enabled")
msg32 = _hash32(msg, raw, digest)
raw_sig = ffi.new('secp256k1_ecdsa_recoverable_signature *')
signed = lib.secp256k1_ecdsa_sign_recoverable(
self.ctx, raw_sig, msg32, self.private_key, ffi.NULL, ffi.NULL)
assert signed == 1
return raw_sig
def schnorr_sign(self, msg, raw=False, digest=hashlib.sha256):
if not HAS_SCHNORR:
raise Exception("secp256k1_schnorr not enabled")
msg32 = _hash32(msg, raw, digest)
sig64 = ffi.new('char [64]')
signed = lib.secp256k1_schnorr_sign(
self.ctx, sig64, msg32, self.private_key, ffi.NULL, ffi.NULL)
assert signed == 1
return bytes(ffi.buffer(sig64, 64))
def schnorr_generate_nonce_pair(self, msg, raw=False,
digest=hashlib.sha256):
"""
Generate a nonce pair deterministically for use with
schnorr_partial_sign.
"""
if not HAS_SCHNORR:
raise Exception("secp256k1_schnorr not enabled")
msg32 = _hash32(msg, raw, digest)
pubnonce = ffi.new('secp256k1_pubkey *')
privnonce = ffi.new('char [32]')
valid = lib.secp256k1_schnorr_generate_nonce_pair(
self.ctx, pubnonce, privnonce, msg32, self.private_key,
ffi.NULL, ffi.NULL)
assert valid == 1
return pubnonce, privnonce
def schnorr_partial_sign(self, msg, privnonce, pubnonce_others,
raw=False, digest=hashlib.sha256):
"""
Produce a partial Schnorr signature, which can be combined using
schnorr_partial_combine to end up with a full signature that is
verifiable using PublicKey.schnorr_verify.
To combine pubnonces, use PublicKey.combine.
Do not pass the pubnonce produced for the respective privnonce;
combine the pubnonces from other signers and pass that instead.
"""
if not HAS_SCHNORR:
raise Exception("secp256k1_schnorr not enabled")
msg32 = _hash32(msg, raw, digest)
sig64 = ffi.new('char [64]')
res = lib.secp256k1_schnorr_partial_sign(
self.ctx, sig64, msg32, self.private_key,
pubnonce_others, privnonce)
if res <= 0:
raise Exception('failed to partially sign ({})'.format(res))
return bytes(ffi.buffer(sig64, 64))
def _hash32(msg, raw, digest):
if not raw:
msg32 = digest(msg).digest()
else:
msg32 = msg
if len(msg32) * 8 != 256:
raise Exception("digest function must produce 256 bits")
return msg32
def _gen_private_key():
key = os.urandom(32)
return key
def _tweak_public(inst, func, scalar):
if not isinstance(scalar, bytes) or len(scalar) != 32:
raise TypeError('scalar must be composed of 32 bytes')
assert inst.public_key, "No public key defined."
# Create a copy of the current public key.
newpub = PublicKey(inst.serialize(), raw=True)
res = func(inst.ctx, newpub.public_key, scalar)
if not res:
raise Exception("Tweak is out of range")
return newpub
def _tweak_private(inst, func, scalar):
if not isinstance(scalar, bytes) or len(scalar) != 32:
raise TypeError('scalar must be composed of 32 bytes')
# Create a copy of the current private key.
key = ffi.new('char [32]', inst.private_key)
res = func(inst.ctx, key, scalar)
if not res:
raise Exception("Tweak is out of range")
return bytes(ffi.buffer(key, 32))
def _main_cli(args, out, encoding='utf-8'):
import binascii
def show_public(public_key):
rawp = public_key.serialize()
out.write(u"Public key: {}\n".format(
binascii.hexlify(rawp).decode(encoding)))
def sign(funcname, params):
raw = bytes(bytearray.fromhex(params.private_key))
priv = PrivateKey(raw)
func = getattr(priv, funcname)
sig = func(params.message)
return priv, sig
if args.action == 'privkey':
if args.private_key:
rawkey = bytes(bytearray.fromhex(args.private_key))
else:
rawkey = None
priv = PrivateKey(rawkey)
raw = priv.private_key
out.write(u"{}\n".format(binascii.hexlify(raw).decode(encoding)))
if args.show_pubkey:
show_public(priv.pubkey)
elif args.action == 'sign':
priv, sig_raw = sign('ecdsa_sign', args)
sig = priv.ecdsa_serialize(sig_raw)
out.write(u"{}\n".format(binascii.hexlify(sig).decode(encoding)))
if args.show_pubkey:
show_public(priv.pubkey)
elif args.action == 'checksig':
raw = bytes(bytearray.fromhex(args.public_key))
sig = bytes(bytearray.fromhex(args.signature))
pub = PublicKey(raw, raw=True)
try:
sig_raw = pub.ecdsa_deserialize(sig)
good = pub.ecdsa_verify(args.message, sig_raw)
except:
good = False
out.write(u"{}\n".format(good))
return 0 if good else 1
elif args.action == 'signrec':
priv, sig = sign('ecdsa_sign_recoverable', args)
sig, recid = priv.ecdsa_recoverable_serialize(sig)
out.write(u"{} {}\n".format(binascii.hexlify(sig).decode(encoding), recid))
if args.show_pubkey:
show_public(priv.pubkey)
elif args.action == 'recpub':
empty = PublicKey(flags=ALL_FLAGS)
sig_raw = bytes(bytearray.fromhex(args.signature))
sig = empty.ecdsa_recoverable_deserialize(sig_raw, args.recid)
pubkey = empty.ecdsa_recover(args.message, sig)
show_public(PublicKey(pubkey))
return 0
def _parse_cli():
import sys
from argparse import ArgumentParser
py2 = sys.version_info.major == 2
enc = sys.getfilesystemencoding()
def bytes_input(s):
return s if py2 else s.encode(enc)
parser = ArgumentParser(prog="secp256k1")
subparser = parser.add_subparsers(dest='action')
genparser = subparser.add_parser('privkey')
genparser.add_argument('-p', '--show-pubkey', action='store_true')
genparser.add_argument('-k', '--private_key')
sign = subparser.add_parser('sign')
sign.add_argument('-k', '--private-key', required=True)
sign.add_argument('-m', '--message', required=True, type=bytes_input)
sign.add_argument('-p', '--show-pubkey', action='store_true')
signrec = subparser.add_parser('signrec')
signrec.add_argument('-k', '--private-key', required=True)
signrec.add_argument('-m', '--message', required=True, type=bytes_input)
signrec.add_argument('-p', '--show-pubkey', action='store_true')
check = subparser.add_parser('checksig')
check.add_argument('-p', '--public-key', required=True)
check.add_argument('-m', '--message', required=True, type=bytes_input)
check.add_argument('-s', '--signature', required=True)
recpub = subparser.add_parser('recpub')
recpub.add_argument('-m', '--message', required=True, type=bytes_input)
recpub.add_argument('-i', '--recid', required=True, type=int)
recpub.add_argument('-s', '--signature', required=True)
return parser, enc
def main():
import sys
parser, enc = _parse_cli()
args = parser.parse_args(sys.argv[1:])
sys.exit(_main_cli(args, sys.stdout, enc))
if __name__ == '__main__':
main()