def generate_key_ecdsa(ecdsa_curve):
curve = ec.get_curve_for_oid(get_curve_by_hex_oid(ecdsa_curve))
assert not(curve is None)
PrivateKey = ec.generate_private_key(curve(), default_backend())
PublicKey = PrivateKey.public_key()
return PublicKey, PrivateKey
def ecdh(ecdsa_curve, PrivateKey, PublicKey):
curve = ec.get_curve_for_oid(get_curve_by_hex_oid(ecdsa_curve))
assert not(curve is None)
pub = ec.EllipticCurvePublicKey.from_encoded_point(curve(), PublicKey)
prv = ec.derive_private_key(int(hexlify(PrivateKey), 16), curve(), default_backend())
shared_secret = prv.exchange(ec.ECDH(), pub)
return shared_secret
def verify_signature_ecdsa(pk_info, digest, sig, ecdsa_curve):
curve = ec.get_curve_for_oid(get_curve_by_hex_oid(ecdsa_curve))
assert not(curve is None)
pub = ec.EllipticCurvePublicKey.from_encoded_point(curve(), pk_info)
sig = fill_sign(sig)
try:
pub.verify(sig, digest, ec.ECDSA(utils.Prehashed(hashes.SHA256())))
return True
except InvalidSignature:
return False
def ECDSACheckPublicKey(curve_oid, public_key):
assert len(public_key) > 2
assert public_key[0] == 0x04
curve = ec.get_curve_for_oid(ecdsa_keys.get_curve_by_hex_oid(curve_oid))
assert not (curve is None)
assert ecdsa_keys.curve_keysize_bytes(curve) * 2 + 1 == len(public_key)
length = (len(public_key) - 1) // 2
x = public_key[1:length + 1]
y = public_key[length + 1:]
assert len(x) == len(y)
pub = ec.EllipticCurvePublicKey.from_encoded_point(curve(), public_key)
return not (pub is None)
def test_get_curve_for_oid():
assert ec.get_curve_for_oid(ec.EllipticCurveOID.SECP256R1) == ec.SECP256R1
with pytest.raises(LookupError):
ec.get_curve_for_oid(x509.ObjectIdentifier("1.1.1.1"))
def test_get_curve_for_oid():
assert ec.get_curve_for_oid(ec.EllipticCurveOID.SECP256R1) == ec.SECP256R1
with pytest.raises(LookupError):
ec.get_curve_for_oid(x509.ObjectIdentifier("1.1.1.1"))
def lookup_ec_by_oid(service: IOService = Provide[Container.service]):
dotted_string = service.input(
"Give the Elliptic Curve's dotted string")
return ec.get_curve_for_oid(ObjectIdentifier(dotted_string))