def secp256k1_compressed_pubkey_to_uncompressed_pubkey( pubkey ):
"""
convert a secp256k1 compressed public key into an uncompressed public key.
taken from https://bitcointalk.org/index.php?topic=644919.msg7205689#msg7205689
"""
pubk = ECPublicKey(pubkey).to_hex()
assert len(pubk) == 66, "Not a compressed hex public key"
def pow_mod(x, y, z):
"Calculate (x ** y) % z efficiently."
number = 1
while y:
if y & 1:
number = number * x % z
y >>= 1
x = x * x % z
return number
p = ecdsa.SECP256k1.curve.p()
b = ecdsa.SECP256k1.curve.b()
y_parity = int(pubk[:2]) - 2
x = int(pubk[2:], 16)
a = (pow_mod(x, 3, p) + b) % p
y = pow_mod(a, (p+1)//4, p)
if y % 2 != y_parity:
y = -y % p
uncompressed_pubk = '04{:x}{:x}'.format(x, y)
return uncompressed_pubk
def get_pubkey_addresses( pubkey ):
"""
Get the compressed and uncompressed addresses
for a public key. Useful for verifying
signatures by key address.
If we're running in testnet mode, then use
the testnet version byte.
Return (compressed address, uncompressed address)
"""
public_key_object = ECPublicKey(pubkey, version_byte=virtualchain.version_byte)
compressed_address = None
uncompressed_address = None
if public_key_object._type == PubkeyType.compressed:
compressed_address = public_key_object.address()
uncompressed_address = bin_hash160_to_address(
bin_hash160(
decompress(public_key_object.to_bin())
),
version_byte=virtualchain.version_byte
)
elif public_key_object._type == PubkeyType.uncompressed:
compressed_address = bin_hash160_to_address(
bin_hash160(
compress(public_key_object.to_bin())
),
version_byte=virtualchain.version_byte
)
uncompressed_address = public_key_object.address()
else:
raise Exception("Invalid public key")
return (compressed_address, uncompressed_address)
def get_pubkey_addresses(pubkey):
"""
Get the compressed and uncompressed addresses
for a public key. Useful for verifying
signatures by key address.
If we're running in testnet mode, then use
the testnet version byte.
Return (compressed address, uncompressed address)
"""
version_byte = virtualchain.version_byte
compressed_address, uncompressed_address = None, None
pubkey = ECPublicKey(pubkey, version_byte=version_byte)
pubkey_bin = pubkey.to_bin()
if pubkey._type == PubkeyType.compressed:
compressed_address = pubkey.address()
uncompressed_address = decompress(pubkey_bin)
hashed_address = bin_hash160(uncompressed_address)
uncompressed_address = bin_hash160_to_address(
hashed_address, version_byte=version_byte)
elif pubkey._type == PubkeyType.uncompressed:
uncompressed_address = pubkey.address()
compressed_address = compress(pubkey_bin)
hashed_address = bin_hash160(compressed_address)
compressed_address = bin_hash160_to_address(hashed_address,
version_byte=version_byte)
else:
raise Exception('Invalid public key')
return compressed_address, uncompressed_address
def load_verifying_key(verifying_key, crypto_backend=default_backend()):
""" Optional: crypto backend object from the "cryptography" python library
"""
if isinstance(verifying_key, EllipticCurvePublicKey):
return verifying_key
elif isinstance(verifying_key, (str, unicode)):
if is_hex(verifying_key):
try:
public_key_pem = ECPublicKey(verifying_key).to_pem()
except:
pass
else:
try:
return load_pem_public_key(public_key_pem,
backend=crypto_backend)
except Exception as e:
traceback.print_exc()
raise InvalidPublicKeyError()
try:
return load_der_public_key(verifying_key,
backend=crypto_backend)
except:
raise InvalidPublicKeyError()
else:
try:
return load_pem_public_key(verifying_key,
backend=crypto_backend)
except Exception as e:
raise InvalidPublicKeyError()
else:
raise ValueError('Verifying key must be in string or unicode format.')
def setUp(self):
self.reference = {
'hex_public_key':
'02068fd9d47283fb310e6dfb66b141dd78fbabc76d073d48cddc770ffb2bd262d7',
'bin_public_key':
'\x02\x06\x8f\xd9\xd4r\x83\xfb1\x0em\xfbf\xb1A\xddx\xfb\xab\xc7m\x07=H\xcd\xdcw\x0f\xfb+\xd2b\xd7',
'hex_hash160': '25488b0d3bb770d6e0ef07e1f19d33ab59931dee',
'bin_hash160':
'%H\x8b\r;\xb7p\xd6\xe0\xef\x07\xe1\xf1\x9d3\xabY\x93\x1d\xee',
'address': '14Q8uVAX29RUMvqPGXL5sg6NiwwMRFCm8C',
}
self.public_key = ECPublicKey(self.reference['hex_public_key'])
def verify_token(token, public_key_or_address, signing_algorithm="ES256K"):
""" A function for validating an individual token.
"""
decoded_token = decode_token(token)
decoded_token_payload = decoded_token["payload"]
if "subject" not in decoded_token_payload:
raise ValueError("Token doesn't have a subject")
if "publicKey" not in decoded_token_payload["subject"]:
raise ValueError("Token doesn't have a subject public key")
if "issuer" not in decoded_token_payload:
raise ValueError("Token doesn't have an issuer")
if "publicKey" not in decoded_token_payload["issuer"]:
raise ValueError("Token doesn't have an issuer public key")
if "claim" not in decoded_token_payload:
raise ValueError("Token doesn't have a claim")
issuer_public_key = str(decoded_token_payload["issuer"]["publicKey"])
public_key_object = ECPublicKey(issuer_public_key)
compressed_public_key = compress(issuer_public_key)
decompressed_public_key = decompress(issuer_public_key)
if public_key_object._type == PubkeyType.compressed:
compressed_address = public_key_object.address()
uncompressed_address = bin_hash160_to_address(
bin_hash160(decompress(public_key_object.to_bin())))
elif public_key_object._type == PubkeyType.uncompressed:
compressed_address = bin_hash160_to_address(
bin_hash160(compress(public_key_object.to_bin())))
uncompressed_address = public_key_object.address()
else:
raise ValueError("Invalid issuer public key format")
if public_key_or_address == compressed_public_key:
pass
elif public_key_or_address == decompressed_public_key:
pass
elif public_key_or_address == compressed_address:
pass
elif public_key_or_address == uncompressed_address:
pass
else:
raise ValueError("Token public key doesn't match the verifying value")
token_verifier = TokenVerifier()
if not token_verifier.verify(token, public_key_object.to_pem()):
raise ValueError("Token was not signed by the issuer public key")
return decoded_token
def verify_raw_data(raw_data, pubkey, sigb64):
"""
Verify the signature over a string, given the public key
and base64-encode signature.
Return True on success.
Return False on error.
"""
data_hash = get_data_hash(raw_data)
pubk = ECPublicKey(pubkey).to_hex()
if len(pubk) == 66:
pubk = secp256k1_compressed_pubkey_to_uncompressed_pubkey( pubkey )
sig_bin = base64.b64decode(sigb64)
vk = ecdsa.VerifyingKey.from_string( pubk[2:].decode('hex'), curve=ecdsa.SECP256k1 )
return vk.verify_digest(sig_bin, data_hash.decode('hex'), sigdecode=ecdsa.util.sigdecode_der)
def setUp(self):
self.ref = _compressed_info_2
self.public_key = ECPublicKey(self.ref['hex_public_key'])
def setUp(self):
self.public_key = ECPublicKey(self.ref['hex_public_key'])
def test_create_pubkey_from_bin_compressed_format(self):
public_key_string = self.ref['bin_public_key_compressed']
self.assertEqual(self.address_compressed, ECPublicKey(
public_key_string).address())
def test_create_pubkey_from_hex_ecdsa_format(self):
public_key_string = self.ref['hex_public_key_raw_ecdsa']
self.assertEqual(self.address_uncompressed, ECPublicKey(
public_key_string).address())
def test_create_pubkey_from_bin_ecdsa_format(self):
public_key_string = '\x06\x8f\xd9\xd4r\x83\xfb1\x0em\xfbf\xb1A\xddx\xfb\xab\xc7m\x07=H\xcd\xdcw\x0f\xfb+\xd2b\xd7\xb2\x83/\x87\xf6\x83\x10\x0b\x89\xc2\xe9S\x14\xde\xee\xac\xbcd\t\xaf\x1e6\xc3\xae?\xd8\xc5\xf2\xf2C\xcf\xec'
self.assertEqual(self.address_uncompressed,
ECPublicKey(public_key_string).address())
def test_create_pubkey_from_hex_ecdsa_format(self):
public_key_string = '068fd9d47283fb310e6dfb66b141dd78fbabc76d073d48cddc770ffb2bd262d7b2832f87f683100b89c2e95314deeeacbc6409af1e36c3ae3fd8c5f2f243cfec'
self.assertEqual(self.address_uncompressed,
ECPublicKey(public_key_string).address())
def test_create_pubkey_from_bin_compressed_format(self):
public_key_string = '\x02\x06\x8f\xd9\xd4r\x83\xfb1\x0em\xfbf\xb1A\xddx\xfb\xab\xc7m\x07=H\xcd\xdcw\x0f\xfb+\xd2b\xd7'
self.assertEqual(self.address_compressed,
ECPublicKey(public_key_string).address())
def test_create_pubkey_from_hex_compressed_format(self):
public_key_string = '02068fd9d47283fb310e6dfb66b141dd78fbabc76d073d48cddc770ffb2bd262d7'
self.assertEqual(self.address_compressed,
ECPublicKey(public_key_string).address())