# 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
from functools import partial
-from pygost.gost3413 import pad1
from pygost.gost3413 import pad2
+from pygost.gost3413 import pad_size
+from pygost.gost3413 import unpad2
from pygost.utils import hexdec
from pygost.utils import strxor
from pygost.utils import xrange # pylint: disable=redefined-builtin
(13, 14, 4, 1, 7, 0, 5, 10, 3, 12, 8, 15, 6, 2, 9, 11),
(1, 3, 10, 9, 5, 11, 4, 15, 8, 6, 7, 14, 13, 0, 2, 12),
),
- "AppliedCryptography": (
- (4, 10, 9, 2, 13, 8, 0, 14, 6, 11, 1, 12, 7, 15, 5, 3),
- (14, 11, 4, 12, 6, 13, 15, 10, 2, 3, 8, 1, 0, 7, 5, 9),
- (5, 8, 1, 13, 10, 3, 4, 2, 14, 15, 12, 7, 6, 0, 9, 11),
- (7, 13, 10, 1, 0, 8, 9, 15, 14, 4, 6, 12, 11, 2, 5, 3),
- (6, 12, 7, 1, 5, 15, 13, 8, 4, 10, 9, 14, 0, 3, 11, 2),
- (4, 11, 10, 0, 7, 2, 1, 13, 3, 6, 8, 5, 9, 12, 15, 14),
- (13, 11, 4, 1, 3, 15, 5, 9, 0, 10, 14, 7, 6, 8, 2, 12),
- (1, 15, 13, 0, 5, 7, 10, 4, 9, 2, 3, 14, 6, 11, 8, 12),
- ),
"Gost28147_tc26_ParamZ": (
(12, 4, 6, 2, 10, 5, 11, 9, 14, 8, 13, 7, 0, 3, 15, 1),
(6, 8, 2, 3, 9, 10, 5, 12, 1, 14, 4, 7, 11, 13, 0, 15),
(7, 14, 12, 13, 9, 4, 8, 15, 10, 2, 6, 0, 3, 11, 5, 1),
),
}
+SBOXES["AppliedCryptography"] = SBOXES["GostR3411_94_TestParamSet"]
def _K(s, _in):
:param bytes key: encryption key
:param bytes data: ciphertext
- :param iv: initialization vector
- :type iv: bytes, BLOCKSIZE length
:type bool pad: perform ISO/IEC 7816-4 unpadding after decryption
:param sbox: S-box parameters to use
:type sbox: str, SBOXES'es key
data[i - BLOCKSIZE:i],
))
if pad:
- last_block = bytearray(plaintext[-1])
- pad_index = last_block.rfind(b"\x80")
- if pad_index == -1:
- raise ValueError("Invalid padding")
- for c in last_block[pad_index + 1:]:
- if c != 0:
- raise ValueError("Invalid padding")
- plaintext[-1] = bytes(last_block[:pad_index])
+ plaintext[-1] = unpad2(plaintext[-1], BLOCKSIZE)
return b"".join(plaintext)
if not data:
raise ValueError("No data supplied")
n2, n1 = encrypt(sbox, key, block2ns(iv))
- size = len(data)
- data = pad1(data, BLOCKSIZE)
gamma = []
- for _ in xrange(0, len(data), BLOCKSIZE):
+ for _ in xrange(0, len(data) + pad_size(len(data), BLOCKSIZE), BLOCKSIZE):
n1 = addmod(n1, C2, 2 ** 32)
n2 = addmod(n2, C1, 2 ** 32 - 1)
gamma.append(ns2block(encrypt(sbox, key, (n1, n2))))
- return strxor(b"".join(gamma), data[:size])
+ return strxor(b"".join(gamma), data)
MESH_CONST = hexdec("6900722264C904238D3ADB9646E92AC418FEAC9400ED0712C086DCC2EF4CA92B")
validate_sbox(sbox)
if not data:
raise ValueError("No data supplied")
- size = len(data)
- data = pad1(data, BLOCKSIZE)
ciphertext = [iv]
- for i in xrange(0, len(data), BLOCKSIZE):
+ for i in xrange(0, len(data) + pad_size(len(data), BLOCKSIZE), BLOCKSIZE):
if mesh and i >= MESH_MAX_DATA and i % MESH_MAX_DATA == 0:
key, iv = meshing(key, ciphertext[-1], sbox=sbox)
ciphertext.append(strxor(
data[i:i + BLOCKSIZE],
ns2block(encrypt(sbox, key, block2ns(ciphertext[-1]))),
))
- return b"".join(ciphertext[1:])[:size]
+ return b"".join(ciphertext[1:])
def cfb_decrypt(key, data, iv=8 * b"\x00", sbox=DEFAULT_SBOX, mesh=False):
validate_sbox(sbox)
if not data:
raise ValueError("No data supplied")
- size = len(data)
- data = pad1(data, BLOCKSIZE)
plaintext = []
data = iv + data
- for i in xrange(BLOCKSIZE, len(data), BLOCKSIZE):
+ for i in xrange(BLOCKSIZE, len(data) + pad_size(len(data), BLOCKSIZE), BLOCKSIZE):
if (
mesh and
(i - BLOCKSIZE) >= MESH_MAX_DATA and
data[i:i + BLOCKSIZE],
ns2block(encrypt(sbox, key, block2ns(data[i - BLOCKSIZE:i]))),
))
- return b"".join(plaintext)[:size]
+ return b"".join(plaintext)