Fix 34.10 degree sanitizing

[pygost.git] / pygost / gost3410.py

diff --git a/pygost/gost3410.py b/pygost/gost3410.py
index ed84f3efbd88d5895e10b6eb9c669b6cadf06449..f6089128d9571ce606ef518dc2c9885c56c86868 100644 (file)
--- a/pygost/gost3410.py
+++ b/pygost/gost3410.py
@@ -1,6 +1,6 @@
 # coding: utf-8
 # PyGOST -- Pure Python GOST cryptographic functions library
-# Copyright (C) 2015-2016 Sergey Matveev <stargrave@stargrave.org>
+# Copyright (C) 2015-2018 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
@@ -94,6 +94,7 @@ CURVE_PARAMS = {
         "0000000000000000000000000000000000000000000000000000000000000000",
         "41ECE55743711A8C3CBF3783CD08C0EE4D4DC440D4641A8F366E550DFDB3BB67",
     ),
+    # pylint: disable=line-too-long
     "GostR3410_2012_TC26_ParamSetA": (
         "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFDC7",
         "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF27E69532F48D89116FF22B8D4E0560609B4B38ABFAD2B85DCACDB1411F10B275",
@@ -110,6 +111,7 @@ CURVE_PARAMS = {
         "00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002",
         "1A8F7EDA389B094C2C071E3647A8940F3C123B697578C213BE6DD9E6C8EC7335DCB228FD1EDF4A39152CBCAAF8C0398828041055F94CEEEC7E21340780FE41BD"
     ),
+    # pylint: enable=line-too-long
 }
 for c, params in CURVE_PARAMS.items():
     CURVE_PARAMS[c] = [hexdec(param) for param in params]
@@ -162,9 +164,9 @@ class GOST3410Curve(object):
         y = y or self.y
         tx = x
         ty = y
-        degree -= 1
         if degree == 0:
             raise ValueError("Bad degree value")
+        degree -= 1
         while degree != 0:
             if degree & 1 == 1:
                 tx, ty = self._add(tx, ty, x, y)
@@ -173,25 +175,25 @@ class GOST3410Curve(object):
         return tx, ty
 
 
-def public_key(curve, private_key):
+def public_key(curve, prv):
     """ Generate public key from the private one
 
     :param GOST3410Curve curve: curve to use
-    :param long private_key: private key
-    :return: public key's parts, X and Y
+    :param long prv: private key
+    :returns: public key's parts, X and Y
     :rtype: (long, long)
     """
-    return curve.exp(private_key)
+    return curve.exp(prv)
 
 
-def sign(curve, private_key, digest, mode=2001):
+def sign(curve, prv, digest, mode=2001):
     """ Calculate signature for provided digest
 
     :param GOST3410Curve curve: curve to use
-    :param long private_key: private key
+    :param long prv: private key
     :param digest: digest for signing
     :type digest: bytes, 32 or 64 bytes
-    :return: signature
+    :returns: signature
     :rtype: bytes, 64 or 128 bytes
     """
     size = MODE2SIZE[mode]
@@ -207,7 +209,7 @@ def sign(curve, private_key, digest, mode=2001):
         r %= q
         if r == 0:
             continue
-        d = private_key * r
+        d = prv * r
         k *= e
         s = (d + k) % q
         if s == 0:
@@ -260,13 +262,13 @@ def verify(curve, pub, digest, signature, mode=2001):
     return lm == r
 
 
-def prv_unmarshal(private_key):
+def prv_unmarshal(prv):
     """Unmarshal private key
 
-    :param bytes private_key: serialized private key
+    :param bytes prv: serialized private key
     :rtype: long
     """
-    return bytes2long(private_key[::-1])
+    return bytes2long(prv[::-1])
 
 
 def pub_marshal(pub, mode=2001):