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Diffstat (limited to 'frozen_deps/Crypto/Protocol/KDF.py')
| -rw-r--r-- | frozen_deps/Crypto/Protocol/KDF.py | 123 |
1 files changed, 0 insertions, 123 deletions
diff --git a/frozen_deps/Crypto/Protocol/KDF.py b/frozen_deps/Crypto/Protocol/KDF.py deleted file mode 100644 index af4e2a6..0000000 --- a/frozen_deps/Crypto/Protocol/KDF.py +++ /dev/null @@ -1,123 +0,0 @@ -# -# KDF.py : a collection of Key Derivation Functions -# -# Part of the Python Cryptography Toolkit -# -# =================================================================== -# The contents of this file are dedicated to the public domain. To -# the extent that dedication to the public domain is not available, -# everyone is granted a worldwide, perpetual, royalty-free, -# non-exclusive license to exercise all rights associated with the -# contents of this file for any purpose whatsoever. -# No rights are reserved. -# -# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, -# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF -# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND -# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS -# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN -# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN -# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE -# SOFTWARE. -# =================================================================== - -"""This file contains a collection of standard key derivation functions. - -A key derivation function derives one or more secondary secret keys from -one primary secret (a master key or a pass phrase). - -This is typically done to insulate the secondary keys from each other, -to avoid that leakage of a secondary key compromises the security of the -master key, or to thwart attacks on pass phrases (e.g. via rainbow tables). - -:undocumented: __revision__ -""" - -__revision__ = "$Id$" - -import math -import struct - -from Crypto.Util.py3compat import * -from Crypto.Hash import SHA as SHA1, HMAC -from Crypto.Util.strxor import strxor - -def PBKDF1(password, salt, dkLen, count=1000, hashAlgo=None): - """Derive one key from a password (or passphrase). - - This function performs key derivation according an old version of - the PKCS#5 standard (v1.5). - - This algorithm is called ``PBKDF1``. Even though it is still described - in the latest version of the PKCS#5 standard (version 2, or RFC2898), - newer applications should use the more secure and versatile `PBKDF2` instead. - - :Parameters: - password : string - The secret password or pass phrase to generate the key from. - salt : byte string - An 8 byte string to use for better protection from dictionary attacks. - This value does not need to be kept secret, but it should be randomly - chosen for each derivation. - dkLen : integer - The length of the desired key. Default is 16 bytes, suitable for instance for `Crypto.Cipher.AES`. - count : integer - The number of iterations to carry out. It's recommended to use at least 1000. - hashAlgo : module - The hash algorithm to use, as a module or an object from the `Crypto.Hash` package. - The digest length must be no shorter than ``dkLen``. - The default algorithm is `SHA1`. - - :Return: A byte string of length `dkLen` that can be used as key. - """ - if not hashAlgo: - hashAlgo = SHA1 - password = tobytes(password) - pHash = hashAlgo.new(password+salt) - digest = pHash.digest_size - if dkLen>digest: - raise ValueError("Selected hash algorithm has a too short digest (%d bytes)." % digest) - if len(salt)!=8: - raise ValueError("Salt is not 8 bytes long.") - for i in range(count-1): - pHash = pHash.new(pHash.digest()) - return pHash.digest()[:dkLen] - -def PBKDF2(password, salt, dkLen=16, count=1000, prf=None): - """Derive one or more keys from a password (or passphrase). - - This performs key derivation according to the PKCS#5 standard (v2.0), - by means of the ``PBKDF2`` algorithm. - - :Parameters: - password : string - The secret password or pass phrase to generate the key from. - salt : string - A string to use for better protection from dictionary attacks. - This value does not need to be kept secret, but it should be randomly - chosen for each derivation. It is recommended to be at least 8 bytes long. - dkLen : integer - The cumulative length of the desired keys. Default is 16 bytes, suitable for instance for `Crypto.Cipher.AES`. - count : integer - The number of iterations to carry out. It's recommended to use at least 1000. - prf : callable - A pseudorandom function. It must be a function that returns a pseudorandom string - from two parameters: a secret and a salt. If not specified, HMAC-SHA1 is used. - - :Return: A byte string of length `dkLen` that can be used as key material. - If you wanted multiple keys, just break up this string into segments of the desired length. -""" - password = tobytes(password) - if prf is None: - prf = lambda p,s: HMAC.new(p,s,SHA1).digest() - key = b('') - i = 1 - while len(key)<dkLen: - U = previousU = prf(password,salt+struct.pack(">I", i)) - for j in range(count-1): - previousU = t = prf(password,previousU) - U = strxor(U,t) - key += U - i = i + 1 - return key[:dkLen] - |