diff options
Diffstat (limited to 'lib/Python/Lib/beaker/crypto')
| -rw-r--r-- | lib/Python/Lib/beaker/crypto/__init__.py | 40 | ||||
| -rw-r--r-- | lib/Python/Lib/beaker/crypto/jcecrypto.py | 30 | ||||
| -rw-r--r-- | lib/Python/Lib/beaker/crypto/pbkdf2.py | 342 | ||||
| -rw-r--r-- | lib/Python/Lib/beaker/crypto/pycrypto.py | 31 | ||||
| -rw-r--r-- | lib/Python/Lib/beaker/crypto/util.py | 30 |
5 files changed, 473 insertions, 0 deletions
diff --git a/lib/Python/Lib/beaker/crypto/__init__.py b/lib/Python/Lib/beaker/crypto/__init__.py new file mode 100644 index 000000000..3e26b0c13 --- /dev/null +++ b/lib/Python/Lib/beaker/crypto/__init__.py @@ -0,0 +1,40 @@ +from warnings import warn + +from beaker.crypto.pbkdf2 import PBKDF2, strxor +from beaker.crypto.util import hmac, sha1, hmac_sha1, md5 +from beaker import util + +keyLength = None + +if util.jython: + try: + from beaker.crypto.jcecrypto import getKeyLength, aesEncrypt + keyLength = getKeyLength() + except ImportError: + pass +else: + try: + from beaker.crypto.pycrypto import getKeyLength, aesEncrypt, aesDecrypt + keyLength = getKeyLength() + except ImportError: + pass + +if not keyLength: + has_aes = False +else: + has_aes = True + +if has_aes and keyLength < 32: + warn('Crypto implementation only supports key lengths up to %d bits. ' + 'Generated session cookies may be incompatible with other ' + 'environments' % (keyLength * 8)) + + +def generateCryptoKeys(master_key, salt, iterations): + # NB: We XOR parts of the keystream into the randomly-generated parts, just + # in case os.urandom() isn't as random as it should be. Note that if + # os.urandom() returns truly random data, this will have no effect on the + # overall security. + keystream = PBKDF2(master_key, salt, iterations=iterations) + cipher_key = keystream.read(keyLength) + return cipher_key diff --git a/lib/Python/Lib/beaker/crypto/jcecrypto.py b/lib/Python/Lib/beaker/crypto/jcecrypto.py new file mode 100644 index 000000000..4062d513e --- /dev/null +++ b/lib/Python/Lib/beaker/crypto/jcecrypto.py @@ -0,0 +1,30 @@ +""" +Encryption module that uses the Java Cryptography Extensions (JCE). + +Note that in default installations of the Java Runtime Environment, the +maximum key length is limited to 128 bits due to US export +restrictions. This makes the generated keys incompatible with the ones +generated by pycryptopp, which has no such restrictions. To fix this, +download the "Unlimited Strength Jurisdiction Policy Files" from Sun, +which will allow encryption using 256 bit AES keys. +""" +from javax.crypto import Cipher +from javax.crypto.spec import SecretKeySpec, IvParameterSpec + +import jarray + +# Initialization vector filled with zeros +_iv = IvParameterSpec(jarray.zeros(16, 'b')) + +def aesEncrypt(data, key): + cipher = Cipher.getInstance('AES/CTR/NoPadding') + skeySpec = SecretKeySpec(key, 'AES') + cipher.init(Cipher.ENCRYPT_MODE, skeySpec, _iv) + return cipher.doFinal(data).tostring() + +# magic. +aesDecrypt = aesEncrypt + +def getKeyLength(): + maxlen = Cipher.getMaxAllowedKeyLength('AES/CTR/NoPadding') + return min(maxlen, 256) / 8 diff --git a/lib/Python/Lib/beaker/crypto/pbkdf2.py b/lib/Python/Lib/beaker/crypto/pbkdf2.py new file mode 100644 index 000000000..96dc5fbb2 --- /dev/null +++ b/lib/Python/Lib/beaker/crypto/pbkdf2.py @@ -0,0 +1,342 @@ +#!/usr/bin/python +# -*- coding: ascii -*- +########################################################################### +# PBKDF2.py - PKCS#5 v2.0 Password-Based Key Derivation +# +# Copyright (C) 2007 Dwayne C. Litzenberger <dlitz@dlitz.net> +# All rights reserved. +# +# Permission to use, copy, modify, and distribute this software and its +# documentation for any purpose and without fee is hereby granted, +# provided that the above copyright notice appear in all copies and that +# both that copyright notice and this permission notice appear in +# supporting documentation. +# +# THE AUTHOR PROVIDES THIS SOFTWARE ``AS IS'' AND ANY EXPRESSED 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 AUTHOR 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. +# +# Country of origin: Canada +# +########################################################################### +# Sample PBKDF2 usage: +# from Crypto.Cipher import AES +# from PBKDF2 import PBKDF2 +# import os +# +# salt = os.urandom(8) # 64-bit salt +# key = PBKDF2("This passphrase is a secret.", salt).read(32) # 256-bit key +# iv = os.urandom(16) # 128-bit IV +# cipher = AES.new(key, AES.MODE_CBC, iv) +# ... +# +# Sample crypt() usage: +# from PBKDF2 import crypt +# pwhash = crypt("secret") +# alleged_pw = raw_input("Enter password: ") +# if pwhash == crypt(alleged_pw, pwhash): +# print "Password good" +# else: +# print "Invalid password" +# +########################################################################### +# History: +# +# 2007-07-27 Dwayne C. Litzenberger <dlitz@dlitz.net> +# - Initial Release (v1.0) +# +# 2007-07-31 Dwayne C. Litzenberger <dlitz@dlitz.net> +# - Bugfix release (v1.1) +# - SECURITY: The PyCrypto XOR cipher (used, if available, in the _strxor +# function in the previous release) silently truncates all keys to 64 +# bytes. The way it was used in the previous release, this would only be +# problem if the pseudorandom function that returned values larger than +# 64 bytes (so SHA1, SHA256 and SHA512 are fine), but I don't like +# anything that silently reduces the security margin from what is +# expected. +# +########################################################################### + +__version__ = "1.1" + +from struct import pack +from binascii import b2a_hex +from random import randint + +from base64 import b64encode + +from beaker.crypto.util import hmac as HMAC, hmac_sha1 as SHA1 + +def strxor(a, b): + return "".join([chr(ord(x) ^ ord(y)) for (x, y) in zip(a, b)]) + +class PBKDF2(object): + """PBKDF2.py : PKCS#5 v2.0 Password-Based Key Derivation + + This implementation takes a passphrase and a salt (and optionally an + iteration count, a digest module, and a MAC module) and provides a + file-like object from which an arbitrarily-sized key can be read. + + If the passphrase and/or salt are unicode objects, they are encoded as + UTF-8 before they are processed. + + The idea behind PBKDF2 is to derive a cryptographic key from a + passphrase and a salt. + + PBKDF2 may also be used as a strong salted password hash. The + 'crypt' function is provided for that purpose. + + Remember: Keys generated using PBKDF2 are only as strong as the + passphrases they are derived from. + """ + + def __init__(self, passphrase, salt, iterations=1000, + digestmodule=SHA1, macmodule=HMAC): + if not callable(macmodule): + macmodule = macmodule.new + self.__macmodule = macmodule + self.__digestmodule = digestmodule + self._setup(passphrase, salt, iterations, self._pseudorandom) + + def _pseudorandom(self, key, msg): + """Pseudorandom function. e.g. HMAC-SHA1""" + return self.__macmodule(key=key, msg=msg, + digestmod=self.__digestmodule).digest() + + def read(self, bytes): + """Read the specified number of key bytes.""" + if self.closed: + raise ValueError("file-like object is closed") + + size = len(self.__buf) + blocks = [self.__buf] + i = self.__blockNum + while size < bytes: + i += 1 + if i > 0xffffffff: + # We could return "" here, but + raise OverflowError("derived key too long") + block = self.__f(i) + blocks.append(block) + size += len(block) + buf = "".join(blocks) + retval = buf[:bytes] + self.__buf = buf[bytes:] + self.__blockNum = i + return retval + + def __f(self, i): + # i must fit within 32 bits + assert (1 <= i <= 0xffffffff) + U = self.__prf(self.__passphrase, self.__salt + pack("!L", i)) + result = U + for j in xrange(2, 1+self.__iterations): + U = self.__prf(self.__passphrase, U) + result = strxor(result, U) + return result + + def hexread(self, octets): + """Read the specified number of octets. Return them as hexadecimal. + + Note that len(obj.hexread(n)) == 2*n. + """ + return b2a_hex(self.read(octets)) + + def _setup(self, passphrase, salt, iterations, prf): + # Sanity checks: + + # passphrase and salt must be str or unicode (in the latter + # case, we convert to UTF-8) + if isinstance(passphrase, unicode): + passphrase = passphrase.encode("UTF-8") + if not isinstance(passphrase, str): + raise TypeError("passphrase must be str or unicode") + if isinstance(salt, unicode): + salt = salt.encode("UTF-8") + if not isinstance(salt, str): + raise TypeError("salt must be str or unicode") + + # iterations must be an integer >= 1 + if not isinstance(iterations, (int, long)): + raise TypeError("iterations must be an integer") + if iterations < 1: + raise ValueError("iterations must be at least 1") + + # prf must be callable + if not callable(prf): + raise TypeError("prf must be callable") + + self.__passphrase = passphrase + self.__salt = salt + self.__iterations = iterations + self.__prf = prf + self.__blockNum = 0 + self.__buf = "" + self.closed = False + + def close(self): + """Close the stream.""" + if not self.closed: + del self.__passphrase + del self.__salt + del self.__iterations + del self.__prf + del self.__blockNum + del self.__buf + self.closed = True + +def crypt(word, salt=None, iterations=None): + """PBKDF2-based unix crypt(3) replacement. + + The number of iterations specified in the salt overrides the 'iterations' + parameter. + + The effective hash length is 192 bits. + """ + + # Generate a (pseudo-)random salt if the user hasn't provided one. + if salt is None: + salt = _makesalt() + + # salt must be a string or the us-ascii subset of unicode + if isinstance(salt, unicode): + salt = salt.encode("us-ascii") + if not isinstance(salt, str): + raise TypeError("salt must be a string") + + # word must be a string or unicode (in the latter case, we convert to UTF-8) + if isinstance(word, unicode): + word = word.encode("UTF-8") + if not isinstance(word, str): + raise TypeError("word must be a string or unicode") + + # Try to extract the real salt and iteration count from the salt + if salt.startswith("$p5k2$"): + (iterations, salt, dummy) = salt.split("$")[2:5] + if iterations == "": + iterations = 400 + else: + converted = int(iterations, 16) + if iterations != "%x" % converted: # lowercase hex, minimum digits + raise ValueError("Invalid salt") + iterations = converted + if not (iterations >= 1): + raise ValueError("Invalid salt") + + # Make sure the salt matches the allowed character set + allowed = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789./" + for ch in salt: + if ch not in allowed: + raise ValueError("Illegal character %r in salt" % (ch,)) + + if iterations is None or iterations == 400: + iterations = 400 + salt = "$p5k2$$" + salt + else: + salt = "$p5k2$%x$%s" % (iterations, salt) + rawhash = PBKDF2(word, salt, iterations).read(24) + return salt + "$" + b64encode(rawhash, "./") + +# Add crypt as a static method of the PBKDF2 class +# This makes it easier to do "from PBKDF2 import PBKDF2" and still use +# crypt. +PBKDF2.crypt = staticmethod(crypt) + +def _makesalt(): + """Return a 48-bit pseudorandom salt for crypt(). + + This function is not suitable for generating cryptographic secrets. + """ + binarysalt = "".join([pack("@H", randint(0, 0xffff)) for i in range(3)]) + return b64encode(binarysalt, "./") + +def test_pbkdf2(): + """Module self-test""" + from binascii import a2b_hex + + # + # Test vectors from RFC 3962 + # + + # Test 1 + result = PBKDF2("password", "ATHENA.MIT.EDUraeburn", 1).read(16) + expected = a2b_hex("cdedb5281bb2f801565a1122b2563515") + if result != expected: + raise RuntimeError("self-test failed") + + # Test 2 + result = PBKDF2("password", "ATHENA.MIT.EDUraeburn", 1200).hexread(32) + expected = ("5c08eb61fdf71e4e4ec3cf6ba1f5512b" + "a7e52ddbc5e5142f708a31e2e62b1e13") + if result != expected: + raise RuntimeError("self-test failed") + + # Test 3 + result = PBKDF2("X"*64, "pass phrase equals block size", 1200).hexread(32) + expected = ("139c30c0966bc32ba55fdbf212530ac9" + "c5ec59f1a452f5cc9ad940fea0598ed1") + if result != expected: + raise RuntimeError("self-test failed") + + # Test 4 + result = PBKDF2("X"*65, "pass phrase exceeds block size", 1200).hexread(32) + expected = ("9ccad6d468770cd51b10e6a68721be61" + "1a8b4d282601db3b36be9246915ec82a") + if result != expected: + raise RuntimeError("self-test failed") + + # + # Other test vectors + # + + # Chunked read + f = PBKDF2("kickstart", "workbench", 256) + result = f.read(17) + result += f.read(17) + result += f.read(1) + result += f.read(2) + result += f.read(3) + expected = PBKDF2("kickstart", "workbench", 256).read(40) + if result != expected: + raise RuntimeError("self-test failed") + + # + # crypt() test vectors + # + + # crypt 1 + result = crypt("cloadm", "exec") + expected = '$p5k2$$exec$r1EWMCMk7Rlv3L/RNcFXviDefYa0hlql' + if result != expected: + raise RuntimeError("self-test failed") + + # crypt 2 + result = crypt("gnu", '$p5k2$c$u9HvcT4d$.....') + expected = '$p5k2$c$u9HvcT4d$Sd1gwSVCLZYAuqZ25piRnbBEoAesaa/g' + if result != expected: + raise RuntimeError("self-test failed") + + # crypt 3 + result = crypt("dcl", "tUsch7fU", iterations=13) + expected = "$p5k2$d$tUsch7fU$nqDkaxMDOFBeJsTSfABsyn.PYUXilHwL" + if result != expected: + raise RuntimeError("self-test failed") + + # crypt 4 (unicode) + result = crypt(u'\u0399\u03c9\u03b1\u03bd\u03bd\u03b7\u03c2', + '$p5k2$$KosHgqNo$9mjN8gqjt02hDoP0c2J0ABtLIwtot8cQ') + expected = '$p5k2$$KosHgqNo$9mjN8gqjt02hDoP0c2J0ABtLIwtot8cQ' + if result != expected: + raise RuntimeError("self-test failed") + +if __name__ == '__main__': + test_pbkdf2() + +# vim:set ts=4 sw=4 sts=4 expandtab: diff --git a/lib/Python/Lib/beaker/crypto/pycrypto.py b/lib/Python/Lib/beaker/crypto/pycrypto.py new file mode 100644 index 000000000..a3eb4d9db --- /dev/null +++ b/lib/Python/Lib/beaker/crypto/pycrypto.py @@ -0,0 +1,31 @@ +"""Encryption module that uses pycryptopp or pycrypto""" +try: + # Pycryptopp is preferred over Crypto because Crypto has had + # various periods of not being maintained, and pycryptopp uses + # the Crypto++ library which is generally considered the 'gold standard' + # of crypto implementations + from pycryptopp.cipher import aes + + def aesEncrypt(data, key): + cipher = aes.AES(key) + return cipher.process(data) + + # magic. + aesDecrypt = aesEncrypt + +except ImportError: + from Crypto.Cipher import AES + + def aesEncrypt(data, key): + cipher = AES.new(key) + + data = data + (" " * (16 - (len(data) % 16))) + return cipher.encrypt(data) + + def aesDecrypt(data, key): + cipher = AES.new(key) + + return cipher.decrypt(data).rstrip() + +def getKeyLength(): + return 32 diff --git a/lib/Python/Lib/beaker/crypto/util.py b/lib/Python/Lib/beaker/crypto/util.py new file mode 100644 index 000000000..d97e8ce6f --- /dev/null +++ b/lib/Python/Lib/beaker/crypto/util.py @@ -0,0 +1,30 @@ +from warnings import warn +from beaker import util + + +try: + # Use PyCrypto (if available) + from Crypto.Hash import HMAC as hmac, SHA as hmac_sha1 + sha1 = hmac_sha1.new + +except ImportError: + + # PyCrypto not available. Use the Python standard library. + import hmac + + # When using the stdlib, we have to make sure the hmac version and sha + # version are compatible + if util.py24: + from sha import sha as sha1 + import sha as hmac_sha1 + else: + # NOTE: We have to use the callable with hashlib (hashlib.sha1), + # otherwise hmac only accepts the sha module object itself + from hashlib import sha1 + hmac_sha1 = sha1 + + +if util.py24: + from md5 import md5 +else: + from hashlib import md5 |