/usr/lib/python3/dist-packages/pyelliptic/cipher.py is in python3-pyelliptic 1.5.7-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 | #!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright (c) 2014 Yann GUIBET <yannguibet@gmail.com>.
# All rights reserved.
#
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
# IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
from .openssl import OpenSSL
class Cipher:
"""
Symmetric encryption
import pyelliptic
iv = pyelliptic.Cipher.gen_IV('aes-256-cfb')
ctx = pyelliptic.Cipher("secretkey", iv, 1, ciphername='aes-256-cfb')
ciphertext = ctx.update('test1')
ciphertext += ctx.update('test2')
ciphertext += ctx.final()
ctx2 = pyelliptic.Cipher("secretkey", iv, 0, ciphername='aes-256-cfb')
print ctx2.ciphering(ciphertext)
"""
def __init__(self, key, iv, do, ciphername='aes-256-cbc'):
"""
do == 1 => Encrypt; do == 0 => Decrypt
"""
self.cipher = OpenSSL.get_cipher(ciphername)
self.ctx = OpenSSL.EVP_CIPHER_CTX_new()
if do == 1 or do == 0:
k = OpenSSL.malloc(key, len(key))
IV = OpenSSL.malloc(iv, len(iv))
OpenSSL.EVP_CipherInit_ex(
self.ctx, self.cipher.get_pointer(), 0, k, IV, do)
else:
raise Exception("RTFM ...")
@staticmethod
def get_all_cipher():
"""
static method, returns all ciphers available
"""
return OpenSSL.cipher_algo.keys()
@staticmethod
def get_blocksize(ciphername):
cipher = OpenSSL.get_cipher(ciphername)
return cipher.get_blocksize()
@staticmethod
def gen_IV(ciphername):
cipher = OpenSSL.get_cipher(ciphername)
return OpenSSL.rand(cipher.get_blocksize())
def update(self, input):
i = OpenSSL.c_int(0)
buffer = OpenSSL.malloc(b"", len(input) + self.cipher.get_blocksize())
inp = OpenSSL.malloc(input, len(input))
if OpenSSL.EVP_CipherUpdate(self.ctx, OpenSSL.byref(buffer),
OpenSSL.byref(i), inp, len(input)) == 0:
raise Exception("[OpenSSL] EVP_CipherUpdate FAIL ...")
return buffer.raw[0:i.value]
def final(self):
i = OpenSSL.c_int(0)
buffer = OpenSSL.malloc(b"", self.cipher.get_blocksize())
if (OpenSSL.EVP_CipherFinal_ex(self.ctx, OpenSSL.byref(buffer),
OpenSSL.byref(i))) == 0:
raise Exception("[OpenSSL] EVP_CipherFinal_ex FAIL ...")
return buffer.raw[0:i.value]
def ciphering(self, input):
"""
Do update and final in one method
"""
buff = self.update(input)
return buff + self.final()
def __del__(self):
OpenSSL.EVP_CIPHER_CTX_cleanup(self.ctx)
OpenSSL.EVP_CIPHER_CTX_free(self.ctx)
|