python之加密解密模块pycrypto

以你之姓@ 2021-12-15 15:39 277阅读 0赞

This is a collection of both secure hash functions (such as SHA256 and RIPEMD160), and various encryption algorithms (AES, DES, RSA, ElGamal, etc.). The package is structured to make adding new modules easy. This section is essentially complete, and the software interface will almost certainly not change in an incompatible way in the future; all that remains to be done is to fix any bugs that show up. If you encounter a bug, please report it in the Launchpad bug tracker at

An example usage of the SHA256 module is:

>>> from Crypto.Hash import SHA256
    >>> hash = SHA256.new()
    >>> hash.update('message')
    >>> hash.digest()
    '\xabS\n\x13\xe4Y\x14\x98+y\xf9\xb7\xe3\xfb\xa9\x94\xcf\xd1\xf3\xfb"\xf7\x1c\xea\x1a\xfb\xf0+F\x0cm\x1d'

An example usage of an encryption algorithm (AES, in this case) is:

>>> from Crypto.Cipher import AES
    >>> obj = AES.new('This is a key123', AES.MODE_CBC, 'This is an IV456')
    >>> message = "The answer is no"
    >>> ciphertext = obj.encrypt(message)
    >>> ciphertext
    '\xd6\x83\x8dd!VT\x92\xaa`A\x05\xe0\x9b\x8b\xf1'
    >>> obj2 = AES.new('This is a key123', AES.MODE_CBC, 'This is an IV456')
    >>> obj2.decrypt(ciphertext)
    'The answer is no'

One possible application of the modules is writing secure administration tools. Another application is in writing daemons and servers. Clients and servers can encrypt the data being exchanged and mutually authenticate themselves; daemons can encrypt private data for added security. Python also provides a pleasant framework for prototyping and experimentation with cryptographic algorithms; thanks to its arbitrary-length integers, public key algorithms are easily implemented.

As of PyCrypto 2.1.0, PyCrypto provides an easy-to-use random number generator:

>>> from Crypto import Random
    >>> rndfile = Random.new()
    >>> rndfile.read(16)
    '\xf7.\x838{\x85\xa0\xd3>#}\xc6\xc2jJU'

A stronger version of Python's standard "random" module is also provided:

>>> from Crypto.Random import random
    >>> random.choice(['dogs', 'cats', 'bears'])
    'bears'

Caveat: For the random number generator to work correctly, you must call Random.atfork() in both the parent and child processes after using os.fork()