X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=pygost%2Fgost3413.py;h=3a539d2e4b1f9097e78774ea3cf263df648a9d5a;hb=54735617392b3988c2e24b59e0c552d74736e320;hp=c0201c97ae8d2947aaf149494d444463c6c83a90;hpb=07c62fdaf6ba22a611492ff9ce734d68b5e65a66;p=pygost.git

diff --git a/pygost/gost3413.py b/pygost/gost3413.py
index c0201c9..3a539d2 100644
--- a/pygost/gost3413.py
+++ b/pygost/gost3413.py
@@ -1,11 +1,10 @@
 # coding: utf-8
 # PyGOST -- Pure Python GOST cryptographic functions library
-# Copyright (C) 2015-2017 Sergey Matveev <stargrave@stargrave.org>
+# Copyright (C) 2015-2020 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
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
+# the Free Software Foundation, version 3 of the License.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -75,7 +74,7 @@ def pad3(data, blocksize):
 def ecb_encrypt(encrypter, bs, pt):
     """ECB encryption mode of operation
 
-    :param encrypter: Encrypting function, that takes block as an input
+    :param encrypter: encrypting function, that takes block as an input
     :param int bs: cipher's blocksize
     :param bytes pt: already padded plaintext
     """
@@ -105,7 +104,7 @@ def ecb_decrypt(decrypter, bs, ct):
 def ctr(encrypter, bs, data, iv):
     """Counter mode of operation
 
-    :param encrypter: Encrypting function, that takes block as an input
+    :param encrypter: encrypting function, that takes block as an input
     :param int bs: cipher's blocksize
     :param bytes data: plaintext/ciphertext
     :param bytes iv: half blocksize-sized initialization vector
@@ -125,34 +124,34 @@ def ctr(encrypter, bs, data, iv):
 def ofb(encrypter, bs, data, iv):
     """OFB mode of operation
 
-    :param encrypter: Encrypting function, that takes block as an input
+    :param encrypter: encrypting function, that takes block as an input
     :param int bs: cipher's blocksize
     :param bytes data: plaintext/ciphertext
-    :param bytes iv: double blocksize-sized initialization vector
+    :param bytes iv: blocksize-sized initialization vector
 
     For decryption you use the same function again.
     """
-    if len(iv) < 2 * bs or len(iv) % bs != 0:
+    if len(iv) < bs or len(iv) % bs != 0:
         raise ValueError("Invalid IV size")
     r = [iv[i:i + bs] for i in range(0, len(iv), bs)]
     result = []
     for i in xrange(0, len(data) + pad_size(len(data), bs), bs):
         r = r[1:] + [encrypter(r[0])]
-        result.append(strxor(r[1], data[i:i + bs]))
+        result.append(strxor(r[-1], data[i:i + bs]))
     return b"".join(result)
 
 
 def cbc_encrypt(encrypter, bs, pt, iv):
     """CBC encryption mode of operation
 
-    :param encrypter: Encrypting function, that takes block as an input
+    :param encrypter: encrypting function, that takes block as an input
     :param int bs: cipher's blocksize
     :param bytes pt: already padded plaintext
-    :param bytes iv: double blocksize-sized initialization vector
+    :param bytes iv: blocksize-sized initialization vector
     """
     if not pt or len(pt) % bs != 0:
         raise ValueError("Plaintext is not blocksize aligned")
-    if len(iv) < 2 * bs or len(iv) % bs != 0:
+    if len(iv) < bs or len(iv) % bs != 0:
         raise ValueError("Invalid IV size")
     r = [iv[i:i + bs] for i in range(0, len(iv), bs)]
     ct = []
@@ -168,11 +167,11 @@ def cbc_decrypt(decrypter, bs, ct, iv):
     :param decrypter: Decrypting function, that takes block as an input
     :param int bs: cipher's blocksize
     :param bytes ct: ciphertext
-    :param bytes iv: double blocksize-sized initialization vector
+    :param bytes iv: blocksize-sized initialization vector
     """
     if not ct or len(ct) % bs != 0:
         raise ValueError("Ciphertext is not blocksize aligned")
-    if len(iv) < 2 * bs or len(iv) % bs != 0:
+    if len(iv) < bs or len(iv) % bs != 0:
         raise ValueError("Invalid IV size")
     r = [iv[i:i + bs] for i in range(0, len(iv), bs)]
     pt = []
@@ -186,12 +185,12 @@ def cbc_decrypt(decrypter, bs, ct, iv):
 def cfb_encrypt(encrypter, bs, pt, iv):
     """CFB encryption mode of operation
 
-    :param encrypter: Encrypting function, that takes block as an input
+    :param encrypter: encrypting function, that takes block as an input
     :param int bs: cipher's blocksize
     :param bytes pt: plaintext
-    :param bytes iv: double blocksize-sized initialization vector
+    :param bytes iv: blocksize-sized initialization vector
     """
-    if len(iv) < 2 * bs or len(iv) % bs != 0:
+    if len(iv) < bs or len(iv) % bs != 0:
         raise ValueError("Invalid IV size")
     r = [iv[i:i + bs] for i in range(0, len(iv), bs)]
     ct = []
@@ -204,12 +203,12 @@ def cfb_encrypt(encrypter, bs, pt, iv):
 def cfb_decrypt(encrypter, bs, ct, iv):
     """CFB decryption mode of operation
 
-    :param encrypter: Encrypting function, that takes block as an input
+    :param encrypter: encrypting function, that takes block as an input
     :param int bs: cipher's blocksize
     :param bytes ct: ciphertext
-    :param bytes iv: double blocksize-sized initialization vector
+    :param bytes iv: blocksize-sized initialization vector
     """
-    if len(iv) < 2 * bs or len(iv) % bs != 0:
+    if len(iv) < bs or len(iv) % bs != 0:
         raise ValueError("Invalid IV size")
     r = [iv[i:i + bs] for i in range(0, len(iv), bs)]
     pt = []
@@ -236,7 +235,7 @@ def _mac_ks(encrypter, bs):
 def mac(encrypter, bs, data):
     """MAC (known here as CMAC, OMAC1) mode of operation
 
-    :param encrypter: Encrypting function, that takes block as an input
+    :param encrypter: encrypting function, that takes block as an input
     :param int bs: cipher's blocksize
     :param bytes data: data to authenticate