Fixed typo in parameter

[pygost.git] / pygost / gost3410_vko.py

diff --git a/pygost/gost3410_vko.py b/pygost/gost3410_vko.py
index 4bc2d4e9df85410c7d21d6f7ab88999e1a95b25d..f72a136fe94b41c8a28ee9555f9058687b1d3c89 100644 (file)
--- a/pygost/gost3410_vko.py
+++ b/pygost/gost3410_vko.py
@@ -1,6 +1,6 @@
 # coding: utf-8
 # PyGOST -- Pure Python GOST cryptographic functions library
-# Copyright (C) 2015-2020 Sergey Matveev <stargrave@stargrave.org>
+# Copyright (C) 2015-2024 Sergey Matveev <stargrave@stargrave.org>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -32,14 +32,18 @@ def ukm_unmarshal(ukm):
     return bytes2long(ukm[::-1])
 
 
-def kek(curve, prv, pub, ukm):
+def kek(curve, prv, pub, ukm, mask=None):
+    if not curve.contains(pub):
+        raise ValueError("pub is not on the curve")
     key = curve.exp(prv, pub[0], pub[1])
     key = curve.exp(curve.cofactor * ukm, key[0], key[1])
+    if mask is not None:
+        key = curve.exp(mask, key[0], key[1])
     return pub_marshal(key)
 
 
 def kek_34102001(curve, prv, pub, ukm):
-    """ Key agreement (34.10-2001, 34.11-94)
+    """Key agreement (34.10-2001, 34.11-94)
 
     :param GOST3410Curve curve: curve to use
     :param long prv: private key
@@ -60,7 +64,7 @@ def kek_34102001(curve, prv, pub, ukm):
 
 
 def kek_34102012256(curve, prv, pub, ukm=1):
-    """ Key agreement (34.10-2012, 34.11-2012 256 bit)
+    """Key agreement (34.10-2012, 34.11-2012 256 bit)
 
     :param GOST3410Curve curve: curve to use
     :param long prv: private key
@@ -77,7 +81,7 @@ def kek_34102012256(curve, prv, pub, ukm=1):
 
 
 def kek_34102012512(curve, prv, pub, ukm=1):
-    """ Key agreement (34.10-2012, 34.11-2012 512 bit)
+    """Key agreement (34.10-2012, 34.11-2012 512 bit)
 
     :param GOST3410Curve curve: curve to use
     :param long prv: private key