ó Bd\Rc@s‘dZdZddlmZddlmZdejfd„ƒYZd„ZdZd Z d Z d Z d Z d Z dZdZed dƒZdS(sñBlowfish symmetric cipher Blowfish_ is a symmetric block cipher designed by Bruce Schneier. It has a fixed data block size of 8 bytes and its keys can vary in length from 32 to 448 bits (4 to 56 bytes). Blowfish is deemed secure and it is fast. However, its keys should be chosen to be big enough to withstand a brute force attack (e.g. at least 16 bytes). As an example, encryption can be done as follows: >>> from Crypto.Cipher import Blowfish >>> from Crypto import Random >>> from struct import pack >>> >>> bs = Blowfish.block_size >>> key = b'An arbitrarily long key' >>> iv = Random.new().read(bs) >>> cipher = Blowfish.new(key, Blowfish.MODE_CBC, iv) >>> plaintext = b'docendo discimus ' >>> plen = bs - divmod(len(plaintext),bs)[1] >>> padding = [plen]*plen >>> padding = pack('b'*plen, *padding) >>> msg = iv + cipher.encrypt(plaintext + padding) .. _Blowfish: http://www.schneier.com/blowfish.html :undocumented: __revision__, __package__ s$Id$iÿÿÿÿ(t blockalgo(t _BlowfishtBlowfishCiphercBseZdZd„ZRS(sBlowfish cipher objectcOs tjj|t|||ŽdS(sZInitialize a Blowfish cipher object See also `new()` at the module level.N(Rt BlockAlgot__init__R(tselftkeytargstkwargs((s</usr/lib64/python2.7/site-packages/Crypto/Cipher/Blowfish.pyR=s(t__name__t __module__t__doc__R(((s</usr/lib64/python2.7/site-packages/Crypto/Cipher/Blowfish.pyR:scOst|||ŽS(seCreate a new Blowfish cipher :Parameters: key : byte string The secret key to use in the symmetric cipher. Its length can vary from 4 to 56 bytes. :Keywords: mode : a *MODE_** constant The chaining mode to use for encryption or decryption. Default is `MODE_ECB`. IV : byte string The initialization vector to use for encryption or decryption. It is ignored for `MODE_ECB` and `MODE_CTR`. For `MODE_OPENPGP`, IV must be `block_size` bytes long for encryption and `block_size` +2 bytes for decryption (in the latter case, it is actually the *encrypted* IV which was prefixed to the ciphertext). It is mandatory. For all other modes, it must be `block_size` bytes longs. It is optional and when not present it will be given a default value of all zeroes. counter : callable (*Only* `MODE_CTR`). A stateful function that returns the next *counter block*, which is a byte string of `block_size` bytes. For better performance, use `Crypto.Util.Counter`. segment_size : integer (*Only* `MODE_CFB`).The number of bits the plaintext and ciphertext are segmented in. It must be a multiple of 8. If 0 or not specified, it will be assumed to be 8. :Return: a `BlowfishCipher` object (R(RRR((s</usr/lib64/python2.7/site-packages/Crypto/Cipher/Blowfish.pytnewCs"iiiiiiiii8Ni9(R t __revision__t Crypto.CipherRRRRR tMODE_ECBtMODE_CBCtMODE_CFBtMODE_PGPtMODE_OFBtMODE_CTRt MODE_OPENPGPt block_sizetxrangetkey_size(((s</usr/lib64/python2.7/site-packages/Crypto/Cipher/Blowfish.pyt3s %