Python实现的Blowfish加解密详解编程语言

Blowfish加解密字符串    

# 
# blowfish.py 
# Copyright (C) 2002 Michael Gilfix <[email protected]> 
# 
# This module is open source; you can redistribute it and/or 
# modify it under the terms of the GPL or Artistic License. 
# These licenses are available at http://www.opensource.org 
# 
# This software must be used and distributed in accordance 
# with the law. The author claims no liability for its 
# misuse. 
# 
# This program is distributed in the hope that it will be useful, 
# but WITHOUT ANY WARRANTY; without even the implied warranty of 
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
# 
 
# This software was modified by Ivan Voras: CTR cipher mode of 
# operation was added, together with testing and example code. 
# These changes are (c) 2007./08. Ivan Voras <[email protected]> 
# These changes can be used, modified ad distributed under the 
# GPL or Artistic License, the same as the original module. 
# All disclaimers of warranty from the original module also 
# apply to these changes. 
 
# CBC mode contributed by Joel Edwards <[email protected]>, 
# under the same license conditions. 
 
""" 
Blowfish Encryption 
 
This module is a pure python implementation of Bruce Schneier's 
encryption scheme 'Blowfish'. Blowish is a 16-round Feistel Network 
cipher and offers substantial speed gains over DES. 
 
The key is a string of length anywhere between 64 and 448 bits, or 
equivalently 8 and 56 bytes. The encryption and decryption functions operate 
on 64-bit blocks, or 8 byte strings. 
 
Send questions, comments, bugs my way: 
    Michael Gilfix <[email protected]> 
     
The module has been expanded to include CTR stream encryption/decryption 
mode, built from the primitives from the orignal module. This change 
did not alter any of the base Blowfish code from the original author. 
 
The author of CTR changes is: 
    Ivan Voras <[email protected]> 
""" 
 
import struct, types 
 
__author__ = "Michael Gilfix <[email protected]>" 
 
class Blowfish: 
 
    """Blowfish encryption Scheme 
 
    This class implements the encryption and decryption 
    functionality of the Blowfish cipher. 
 
    Public functions: 
 
        def __init__ (self, key) 
            Creates an instance of blowfish using 'key' 
            as the encryption key. Key is a string of 
            length ranging from 8 to 56 bytes (64 to 448 
            bits). Once the instance of the object is 
            created, the key is no longer necessary. 
 
        def encrypt (self, data): 
            Encrypt an 8 byte (64-bit) block of text 
            where 'data' is an 8 byte string. Returns an 
            8-byte encrypted string. 
 
        def decrypt (self, data): 
            Decrypt an 8 byte (64-bit) encrypted block 
            of text, where 'data' is the 8 byte encrypted 
            string. Returns an 8-byte string of plaintext. 
 
        def cipher (self, xl, xr, direction): 
            Encrypts a 64-bit block of data where xl is 
            the upper 32-bits and xr is the lower 32-bits. 
            'direction' is the direction to apply the 
            cipher, either ENCRYPT or DECRYPT constants. 
            returns a tuple of either encrypted or decrypted 
            data of the left half and right half of the 
            64-bit block. 
 
        def initCTR(self): 
            Initializes CTR engine for encryption or decryption. 
             
        def encryptCTR(self, data): 
            Encrypts an arbitrary string and returns the 
            encrypted string. The method can be called successively 
            for multiple string blocks. 
             
        def decryptCTR(self, data): 
            Decrypts a string encrypted with encryptCTR() and 
            returns the decrypted string. 
             
    Private members: 
 
        def __round_func (self, xl) 
            Performs an obscuring function on the 32-bit 
            block of data 'xl', which is the left half of 
            the 64-bit block of data. Returns the 32-bit 
            result as a long integer. 
 
    """ 
 
    # Cipher directions 
    ENCRYPT = 0 
    DECRYPT = 1 
 
    # For the __round_func 
    modulus = long (2) ** 32 
 
    def __init__ (self, key): 
 
        if not key or len (key) < 8 or len (key) > 56: 
            raise RuntimeError, "Attempted to initialize Blowfish cipher with key of invalid length: %s" % len (key) 
 
        self.p_boxes = [ 
            0x243F6A88, 0x85A308D3, 0x13198A2E, 0x03707344, 
            0xA4093822, 0x299F31D0, 0x082EFA98, 0xEC4E6C89, 
            0x452821E6, 0x38D01377, 0xBE5466CF, 0x34E90C6C, 
            0xC0AC29B7, 0xC97C50DD, 0x3F84D5B5, 0xB5470917, 
            0x9216D5D9, 0x8979FB1B 
        ] 
 
        self.s_boxes = [ 
            [ 
                0xD1310BA6, 0x98DFB5AC, 0x2FFD72DB, 0xD01ADFB7, 
                0xB8E1AFED, 0x6A267E96, 0xBA7C9045, 0xF12C7F99, 
                0x24A19947, 0xB3916CF7, 0x0801F2E2, 0x858EFC16, 
                0x636920D8, 0x71574E69, 0xA458FEA3, 0xF4933D7E, 
                0x0D95748F, 0x728EB658, 0x718BCD58, 0x82154AEE, 
                0x7B54A41D, 0xC25A59B5, 0x9C30D539, 0x2AF26013, 
                0xC5D1B023, 0x286085F0, 0xCA417918, 0xB8DB38EF, 
                0x8E79DCB0, 0x603A180E, 0x6C9E0E8B, 0xB01E8A3E, 
                0xD71577C1, 0xBD314B27, 0x78AF2FDA, 0x55605C60, 
                0xE65525F3, 0xAA55AB94, 0x57489862, 0x63E81440, 
                0x55CA396A, 0x2AAB10B6, 0xB4CC5C34, 0x1141E8CE, 
                0xA15486AF, 0x7C72E993, 0xB3EE1411, 0x636FBC2A, 
                0x2BA9C55D, 0x741831F6, 0xCE5C3E16, 0x9B87931E, 
                0xAFD6BA33, 0x6C24CF5C, 0x7A325381, 0x28958677, 
                0x3B8F4898, 0x6B4BB9AF, 0xC4BFE81B, 0x66282193, 
                0x61D809CC, 0xFB21A991, 0x487CAC60, 0x5DEC8032, 
                0xEF845D5D, 0xE98575B1, 0xDC262302, 0xEB651B88, 
                0x23893E81, 0xD396ACC5, 0x0F6D6FF3, 0x83F44239, 
                0x2E0B4482, 0xA4842004, 0x69C8F04A, 0x9E1F9B5E, 
                0x21C66842, 0xF6E96C9A, 0x670C9C61, 0xABD388F0, 
                0x6A51A0D2, 0xD8542F68, 0x960FA728, 0xAB5133A3, 
                0x6EEF0B6C, 0x137A3BE4, 0xBA3BF050, 0x7EFB2A98, 
                0xA1F1651D, 0x39AF0176, 0x66CA593E, 0x82430E88, 
                0x8CEE8619, 0x456F9FB4, 0x7D84A5C3, 0x3B8B5EBE, 
                0xE06F75D8, 0x85C12073, 0x401A449F, 0x56C16AA6, 
                0x4ED3AA62, 0x363F7706, 0x1BFEDF72, 0x429B023D, 
                0x37D0D724, 0xD00A1248, 0xDB0FEAD3, 0x49F1C09B, 
                0x075372C9, 0x80991B7B, 0x25D479D8, 0xF6E8DEF7, 
                0xE3FE501A, 0xB6794C3B, 0x976CE0BD, 0x04C006BA, 
                0xC1A94FB6, 0x409F60C4, 0x5E5C9EC2, 0x196A2463, 
                0x68FB6FAF, 0x3E6C53B5, 0x1339B2EB, 0x3B52EC6F, 
                0x6DFC511F, 0x9B30952C, 0xCC814544, 0xAF5EBD09, 
                0xBEE3D004, 0xDE334AFD, 0x660F2807, 0x192E4BB3, 
                0xC0CBA857, 0x45C8740F, 0xD20B5F39, 0xB9D3FBDB, 
                0x5579C0BD, 0x1A60320A, 0xD6A100C6, 0x402C7279, 
                0x679F25FE, 0xFB1FA3CC, 0x8EA5E9F8, 0xDB3222F8, 
                0x3C7516DF, 0xFD616B15, 0x2F501EC8, 0xAD0552AB, 
                0x323DB5FA, 0xFD238760, 0x53317B48, 0x3E00DF82, 
                0x9E5C57BB, 0xCA6F8CA0, 0x1A87562E, 0xDF1769DB, 
                0xD542A8F6, 0x287EFFC3, 0xAC6732C6, 0x8C4F5573, 
                0x695B27B0, 0xBBCA58C8, 0xE1FFA35D, 0xB8F011A0, 
                0x10FA3D98, 0xFD2183B8, 0x4AFCB56C, 0x2DD1D35B, 
                0x9A53E479, 0xB6F84565, 0xD28E49BC, 0x4BFB9790, 
                0xE1DDF2DA, 0xA4CB7E33, 0x62FB1341, 0xCEE4C6E8, 
                0xEF20CADA, 0x36774C01, 0xD07E9EFE, 0x2BF11FB4, 
                0x95DBDA4D, 0xAE909198, 0xEAAD8E71, 0x6B93D5A0, 
                0xD08ED1D0, 0xAFC725E0, 0x8E3C5B2F, 0x8E7594B7, 
                0x8FF6E2FB, 0xF2122B64, 0x8888B812, 0x900DF01C, 
                0x4FAD5EA0, 0x688FC31C, 0xD1CFF191, 0xB3A8C1AD, 
                0x2F2F2218, 0xBE0E1777, 0xEA752DFE, 0x8B021FA1, 
                0xE5A0CC0F, 0xB56F74E8, 0x18ACF3D6, 0xCE89E299, 
                0xB4A84FE0, 0xFD13E0B7, 0x7CC43B81, 0xD2ADA8D9, 
                0x165FA266, 0x80957705, 0x93CC7314, 0x211A1477, 
                0xE6AD2065, 0x77B5FA86, 0xC75442F5, 0xFB9D35CF, 
                0xEBCDAF0C, 0x7B3E89A0, 0xD6411BD3, 0xAE1E7E49, 
                0x00250E2D, 0x2071B35E, 0x226800BB, 0x57B8E0AF, 
                0x2464369B, 0xF009B91E, 0x5563911D, 0x59DFA6AA, 
                0x78C14389, 0xD95A537F, 0x207D5BA2, 0x02E5B9C5, 
                0x83260376, 0x6295CFA9, 0x11C81968, 0x4E734A41, 
                0xB3472DCA, 0x7B14A94A, 0x1B510052, 0x9A532915, 
                0xD60F573F, 0xBC9BC6E4, 0x2B60A476, 0x81E67400, 
                0x08BA6FB5, 0x571BE91F, 0xF296EC6B, 0x2A0DD915, 
                0xB6636521, 0xE7B9F9B6, 0xFF34052E, 0xC5855664, 
                0x53B02D5D, 0xA99F8FA1, 0x08BA4799, 0x6E85076A 
            ], 
            [ 
                0x4B7A70E9, 0xB5B32944, 0xDB75092E, 0xC4192623, 
                0xAD6EA6B0, 0x49A7DF7D, 0x9CEE60B8, 0x8FEDB266, 
                0xECAA8C71, 0x699A17FF, 0x5664526C, 0xC2B19EE1, 
                0x193602A5, 0x75094C29, 0xA0591340, 0xE4183A3E, 
                0x3F54989A, 0x5B429D65, 0x6B8FE4D6, 0x99F73FD6, 
                0xA1D29C07, 0xEFE830F5, 0x4D2D38E6, 0xF0255DC1, 
                0x4CDD2086, 0x8470EB26, 0x6382E9C6, 0x021ECC5E, 
                0x09686B3F, 0x3EBAEFC9, 0x3C971814, 0x6B6A70A1, 
                0x687F3584, 0x52A0E286, 0xB79C5305, 0xAA500737, 
                0x3E07841C, 0x7FDEAE5C, 0x8E7D44EC, 0x5716F2B8, 
                0xB03ADA37, 0xF0500C0D, 0xF01C1F04, 0x0200B3FF, 
                0xAE0CF51A, 0x3CB574B2, 0x25837A58, 0xDC0921BD, 
                0xD19113F9, 0x7CA92FF6, 0x94324773, 0x22F54701, 
                0x3AE5E581, 0x37C2DADC, 0xC8B57634, 0x9AF3DDA7, 
                0xA9446146, 0x0FD0030E, 0xECC8C73E, 0xA4751E41, 
                0xE238CD99, 0x3BEA0E2F, 0x3280BBA1, 0x183EB331, 
                0x4E548B38, 0x4F6DB908, 0x6F420D03, 0xF60A04BF, 
                0x2CB81290, 0x24977C79, 0x5679B072, 0xBCAF89AF, 
                0xDE9A771F, 0xD9930810, 0xB38BAE12, 0xDCCF3F2E, 
                0x5512721F, 0x2E6B7124, 0x501ADDE6, 0x9F84CD87, 
                0x7A584718, 0x7408DA17, 0xBC9F9ABC, 0xE94B7D8C, 
                0xEC7AEC3A, 0xDB851DFA, 0x63094366, 0xC464C3D2, 
                0xEF1C1847, 0x3215D908, 0xDD433B37, 0x24C2BA16, 
                0x12A14D43, 0x2A65C451, 0x50940002, 0x133AE4DD, 
                0x71DFF89E, 0x10314E55, 0x81AC77D6, 0x5F11199B, 
                0x043556F1, 0xD7A3C76B, 0x3C11183B, 0x5924A509, 
                0xF28FE6ED, 0x97F1FBFA, 0x9EBABF2C, 0x1E153C6E, 
                0x86E34570, 0xEAE96FB1, 0x860E5E0A, 0x5A3E2AB3, 
                0x771FE71C, 0x4E3D06FA, 0x2965DCB9, 0x99E71D0F, 
                0x803E89D6, 0x5266C825, 0x2E4CC978, 0x9C10B36A, 
                0xC6150EBA, 0x94E2EA78, 0xA5FC3C53, 0x1E0A2DF4, 
                0xF2F74EA7, 0x361D2B3D, 0x1939260F, 0x19C27960, 
                0x5223A708, 0xF71312B6, 0xEBADFE6E, 0xEAC31F66, 
                0xE3BC4595, 0xA67BC883, 0xB17F37D1, 0x018CFF28, 
                0xC332DDEF, 0xBE6C5AA5, 0x65582185, 0x68AB9802, 
                0xEECEA50F, 0xDB2F953B, 0x2AEF7DAD, 0x5B6E2F84, 
                0x1521B628, 0x29076170, 0xECDD4775, 0x619F1510, 
                0x13CCA830, 0xEB61BD96, 0x0334FE1E, 0xAA0363CF, 
                0xB5735C90, 0x4C70A239, 0xD59E9E0B, 0xCBAADE14, 
                0xEECC86BC, 0x60622CA7, 0x9CAB5CAB, 0xB2F3846E, 
                0x648B1EAF, 0x19BDF0CA, 0xA02369B9, 0x655ABB50, 
                0x40685A32, 0x3C2AB4B3, 0x319EE9D5, 0xC021B8F7, 
                0x9B540B19, 0x875FA099, 0x95F7997E, 0x623D7DA8, 
                0xF837889A, 0x97E32D77, 0x11ED935F, 0x16681281, 
                0x0E358829, 0xC7E61FD6, 0x96DEDFA1, 0x7858BA99, 
                0x57F584A5, 0x1B227263, 0x9B83C3FF, 0x1AC24696, 
                0xCDB30AEB, 0x532E3054, 0x8FD948E4, 0x6DBC3128, 
                0x58EBF2EF, 0x34C6FFEA, 0xFE28ED61, 0xEE7C3C73, 
                0x5D4A14D9, 0xE864B7E3, 0x42105D14, 0x203E13E0, 
                0x45EEE2B6, 0xA3AAABEA, 0xDB6C4F15, 0xFACB4FD0, 
                0xC742F442, 0xEF6ABBB5, 0x654F3B1D, 0x41CD2105, 
                0xD81E799E, 0x86854DC7, 0xE44B476A, 0x3D816250, 
                0xCF62A1F2, 0x5B8D2646, 0xFC8883A0, 0xC1C7B6A3, 
                0x7F1524C3, 0x69CB7492, 0x47848A0B, 0x5692B285, 
                0x095BBF00, 0xAD19489D, 0x1462B174, 0x23820E00, 
                0x58428D2A, 0x0C55F5EA, 0x1DADF43E, 0x233F7061, 
                0x3372F092, 0x8D937E41, 0xD65FECF1, 0x6C223BDB, 
                0x7CDE3759, 0xCBEE7460, 0x4085F2A7, 0xCE77326E, 
                0xA6078084, 0x19F8509E, 0xE8EFD855, 0x61D99735, 
                0xA969A7AA, 0xC50C06C2, 0x5A04ABFC, 0x800BCADC, 
                0x9E447A2E, 0xC3453484, 0xFDD56705, 0x0E1E9EC9, 
                0xDB73DBD3, 0x105588CD, 0x675FDA79, 0xE3674340, 
                0xC5C43465, 0x713E38D8, 0x3D28F89E, 0xF16DFF20, 
                0x153E21E7, 0x8FB03D4A, 0xE6E39F2B, 0xDB83ADF7 
            ], 
            [ 
                0xE93D5A68, 0x948140F7, 0xF64C261C, 0x94692934, 
                0x411520F7, 0x7602D4F7, 0xBCF46B2E, 0xD4A20068, 
                0xD4082471, 0x3320F46A, 0x43B7D4B7, 0x500061AF, 
                0x1E39F62E, 0x97244546, 0x14214F74, 0xBF8B8840, 
                0x4D95FC1D, 0x96B591AF, 0x70F4DDD3, 0x66A02F45, 
                0xBFBC09EC, 0x03BD9785, 0x7FAC6DD0, 0x31CB8504, 
                0x96EB27B3, 0x55FD3941, 0xDA2547E6, 0xABCA0A9A, 
                0x28507825, 0x530429F4, 0x0A2C86DA, 0xE9B66DFB, 
                0x68DC1462, 0xD7486900, 0x680EC0A4, 0x27A18DEE, 
                0x4F3FFEA2, 0xE887AD8C, 0xB58CE006, 0x7AF4D6B6, 
                0xAACE1E7C, 0xD3375FEC, 0xCE78A399, 0x406B2A42, 
                0x20FE9E35, 0xD9F385B9, 0xEE39D7AB, 0x3B124E8B, 
                0x1DC9FAF7, 0x4B6D1856, 0x26A36631, 0xEAE397B2, 
                0x3A6EFA74, 0xDD5B4332, 0x6841E7F7, 0xCA7820FB, 
                0xFB0AF54E, 0xD8FEB397, 0x454056AC, 0xBA489527, 
                0x55533A3A, 0x20838D87, 0xFE6BA9B7, 0xD096954B, 
                0x55A867BC, 0xA1159A58, 0xCCA92963, 0x99E1DB33, 
                0xA62A4A56, 0x3F3125F9, 0x5EF47E1C, 0x9029317C, 
                0xFDF8E802, 0x04272F70, 0x80BB155C, 0x05282CE3, 
                0x95C11548, 0xE4C66D22, 0x48C1133F, 0xC70F86DC, 
                0x07F9C9EE, 0x41041F0F, 0x404779A4, 0x5D886E17, 
                0x325F51EB, 0xD59BC0D1, 0xF2BCC18F, 0x41113564, 
                0x257B7834, 0x602A9C60, 0xDFF8E8A3, 0x1F636C1B, 
                0x0E12B4C2, 0x02E1329E, 0xAF664FD1, 0xCAD18115, 
                0x6B2395E0, 0x333E92E1, 0x3B240B62, 0xEEBEB922, 
                0x85B2A20E, 0xE6BA0D99, 0xDE720C8C, 0x2DA2F728, 
                0xD0127845, 0x95B794FD, 0x647D0862, 0xE7CCF5F0, 
                0x5449A36F, 0x877D48FA, 0xC39DFD27, 0xF33E8D1E, 
                0x0A476341, 0x992EFF74, 0x3A6F6EAB, 0xF4F8FD37, 
                0xA812DC60, 0xA1EBDDF8, 0x991BE14C, 0xDB6E6B0D, 
                0xC67B5510, 0x6D672C37, 0x2765D43B, 0xDCD0E804, 
                0xF1290DC7, 0xCC00FFA3, 0xB5390F92, 0x690FED0B, 
                0x667B9FFB, 0xCEDB7D9C, 0xA091CF0B, 0xD9155EA3, 
                0xBB132F88, 0x515BAD24, 0x7B9479BF, 0x763BD6EB, 
                0x37392EB3, 0xCC115979, 0x8026E297, 0xF42E312D, 
                0x6842ADA7, 0xC66A2B3B, 0x12754CCC, 0x782EF11C, 
                0x6A124237, 0xB79251E7, 0x06A1BBE6, 0x4BFB6350, 
                0x1A6B1018, 0x11CAEDFA, 0x3D25BDD8, 0xE2E1C3C9, 
                0x44421659, 0x0A121386, 0xD90CEC6E, 0xD5ABEA2A, 
                0x64AF674E, 0xDA86A85F, 0xBEBFE988, 0x64E4C3FE, 
                0x9DBC8057, 0xF0F7C086, 0x60787BF8, 0x6003604D, 
                0xD1FD8346, 0xF6381FB0, 0x7745AE04, 0xD736FCCC, 
                0x83426B33, 0xF01EAB71, 0xB0804187, 0x3C005E5F, 
                0x77A057BE, 0xBDE8AE24, 0x55464299, 0xBF582E61, 
                0x4E58F48F, 0xF2DDFDA2, 0xF474EF38, 0x8789BDC2, 
                0x5366F9C3, 0xC8B38E74, 0xB475F255, 0x46FCD9B9, 
                0x7AEB2661, 0x8B1DDF84, 0x846A0E79, 0x915F95E2, 
                0x466E598E, 0x20B45770, 0x8CD55591, 0xC902DE4C, 
                0xB90BACE1, 0xBB8205D0, 0x11A86248, 0x7574A99E, 
                0xB77F19B6, 0xE0A9DC09, 0x662D09A1, 0xC4324633, 
                0xE85A1F02, 0x09F0BE8C, 0x4A99A025, 0x1D6EFE10, 
                0x1AB93D1D, 0x0BA5A4DF, 0xA186F20F, 0x2868F169, 
                0xDCB7DA83, 0x573906FE, 0xA1E2CE9B, 0x4FCD7F52, 
                0x50115E01, 0xA70683FA, 0xA002B5C4, 0x0DE6D027, 
                0x9AF88C27, 0x773F8641, 0xC3604C06, 0x61A806B5, 
                0xF0177A28, 0xC0F586E0, 0x006058AA, 0x30DC7D62, 
                0x11E69ED7, 0x2338EA63, 0x53C2DD94, 0xC2C21634, 
                0xBBCBEE56, 0x90BCB6DE, 0xEBFC7DA1, 0xCE591D76, 
                0x6F05E409, 0x4B7C0188, 0x39720A3D, 0x7C927C24, 
                0x86E3725F, 0x724D9DB9, 0x1AC15BB4, 0xD39EB8FC, 
                0xED545578, 0x08FCA5B5, 0xD83D7CD3, 0x4DAD0FC4, 
                0x1E50EF5E, 0xB161E6F8, 0xA28514D9, 0x6C51133C, 
                0x6FD5C7E7, 0x56E14EC4, 0x362ABFCE, 0xDDC6C837, 
                0xD79A3234, 0x92638212, 0x670EFA8E, 0x406000E0 
            ], 
            [ 
                0x3A39CE37, 0xD3FAF5CF, 0xABC27737, 0x5AC52D1B, 
                0x5CB0679E, 0x4FA33742, 0xD3822740, 0x99BC9BBE, 
                0xD5118E9D, 0xBF0F7315, 0xD62D1C7E, 0xC700C47B, 
                0xB78C1B6B, 0x21A19045, 0xB26EB1BE, 0x6A366EB4, 
                0x5748AB2F, 0xBC946E79, 0xC6A376D2, 0x6549C2C8, 
                0x530FF8EE, 0x468DDE7D, 0xD5730A1D, 0x4CD04DC6, 
                0x2939BBDB, 0xA9BA4650, 0xAC9526E8, 0xBE5EE304, 
                0xA1FAD5F0, 0x6A2D519A, 0x63EF8CE2, 0x9A86EE22, 
                0xC089C2B8, 0x43242EF6, 0xA51E03AA, 0x9CF2D0A4, 
                0x83C061BA, 0x9BE96A4D, 0x8FE51550, 0xBA645BD6, 
                0x2826A2F9, 0xA73A3AE1, 0x4BA99586, 0xEF5562E9, 
                0xC72FEFD3, 0xF752F7DA, 0x3F046F69, 0x77FA0A59, 
                0x80E4A915, 0x87B08601, 0x9B09E6AD, 0x3B3EE593, 
                0xE990FD5A, 0x9E34D797, 0x2CF0B7D9, 0x022B8B51, 
                0x96D5AC3A, 0x017DA67D, 0xD1CF3ED6, 0x7C7D2D28, 
                0x1F9F25CF, 0xADF2B89B, 0x5AD6B472, 0x5A88F54C, 
                0xE029AC71, 0xE019A5E6, 0x47B0ACFD, 0xED93FA9B, 
                0xE8D3C48D, 0x283B57CC, 0xF8D56629, 0x79132E28, 
                0x785F0191, 0xED756055, 0xF7960E44, 0xE3D35E8C, 
                0x15056DD4, 0x88F46DBA, 0x03A16125, 0x0564F0BD, 
                0xC3EB9E15, 0x3C9057A2, 0x97271AEC, 0xA93A072A, 
                0x1B3F6D9B, 0x1E6321F5, 0xF59C66FB, 0x26DCF319, 
                0x7533D928, 0xB155FDF5, 0x03563482, 0x8ABA3CBB, 
                0x28517711, 0xC20AD9F8, 0xABCC5167, 0xCCAD925F, 
                0x4DE81751, 0x3830DC8E, 0x379D5862, 0x9320F991, 
                0xEA7A90C2, 0xFB3E7BCE, 0x5121CE64, 0x774FBE32, 
                0xA8B6E37E, 0xC3293D46, 0x48DE5369, 0x6413E680, 
                0xA2AE0810, 0xDD6DB224, 0x69852DFD, 0x09072166, 
                0xB39A460A, 0x6445C0DD, 0x586CDECF, 0x1C20C8AE, 
                0x5BBEF7DD, 0x1B588D40, 0xCCD2017F, 0x6BB4E3BB, 
                0xDDA26A7E, 0x3A59FF45, 0x3E350A44, 0xBCB4CDD5, 
                0x72EACEA8, 0xFA6484BB, 0x8D6612AE, 0xBF3C6F47, 
                0xD29BE463, 0x542F5D9E, 0xAEC2771B, 0xF64E6370, 
                0x740E0D8D, 0xE75B1357, 0xF8721671, 0xAF537D5D, 
                0x4040CB08, 0x4EB4E2CC, 0x34D2466A, 0x0115AF84, 
                0xE1B00428, 0x95983A1D, 0x06B89FB4, 0xCE6EA048, 
                0x6F3F3B82, 0x3520AB82, 0x011A1D4B, 0x277227F8, 
                0x611560B1, 0xE7933FDC, 0xBB3A792B, 0x344525BD, 
                0xA08839E1, 0x51CE794B, 0x2F32C9B7, 0xA01FBAC9, 
                0xE01CC87E, 0xBCC7D1F6, 0xCF0111C3, 0xA1E8AAC7, 
                0x1A908749, 0xD44FBD9A, 0xD0DADECB, 0xD50ADA38, 
                0x0339C32A, 0xC6913667, 0x8DF9317C, 0xE0B12B4F, 
                0xF79E59B7, 0x43F5BB3A, 0xF2D519FF, 0x27D9459C, 
                0xBF97222C, 0x15E6FC2A, 0x0F91FC71, 0x9B941525, 
                0xFAE59361, 0xCEB69CEB, 0xC2A86459, 0x12BAA8D1, 
                0xB6C1075E, 0xE3056A0C, 0x10D25065, 0xCB03A442, 
                0xE0EC6E0E, 0x1698DB3B, 0x4C98A0BE, 0x3278E964, 
                0x9F1F9532, 0xE0D392DF, 0xD3A0342B, 0x8971F21E, 
                0x1B0A7441, 0x4BA3348C, 0xC5BE7120, 0xC37632D8, 
                0xDF359F8D, 0x9B992F2E, 0xE60B6F47, 0x0FE3F11D, 
                0xE54CDA54, 0x1EDAD891, 0xCE6279CF, 0xCD3E7E6F, 
                0x1618B166, 0xFD2C1D05, 0x848FD2C5, 0xF6FB2299, 
                0xF523F357, 0xA6327623, 0x93A83531, 0x56CCCD02, 
                0xACF08162, 0x5A75EBB5, 0x6E163697, 0x88D273CC, 
                0xDE966292, 0x81B949D0, 0x4C50901B, 0x71C65614, 
                0xE6C6C7BD, 0x327A140A, 0x45E1D006, 0xC3F27B9A, 
                0xC9AA53FD, 0x62A80F00, 0xBB25BFE2, 0x35BDD2F6, 
                0x71126905, 0xB2040222, 0xB6CBCF7C, 0xCD769C2B, 
                0x53113EC0, 0x1640E3D3, 0x38ABBD60, 0x2547ADF0, 
                0xBA38209C, 0xF746CE76, 0x77AFA1C5, 0x20756060, 
                0x85CBFE4E, 0x8AE88DD8, 0x7AAAF9B0, 0x4CF9AA7E, 
                0x1948C25C, 0x02FB8A8C, 0x01C36AE4, 0xD6EBE1F9, 
                0x90D4F869, 0xA65CDEA0, 0x3F09252D, 0xC208E69F, 
                0xB74E6132, 0xCE77E25B, 0x578FDFE3, 0x3AC372E6 
            ] 
        ] 
 
        # Cycle through the p-boxes and round-robin XOR the 
        # key with the p-boxes 
        key_len = len (key) 
        index = 0 
        for i in range (len (self.p_boxes)): 
            val = (ord (key[index % key_len]) << 24) + / 
                  (ord (key[(index + 1) % key_len]) << 16) + / 
                  (ord (key[(index + 2) % key_len]) << 8) + / 
                   ord (key[(index + 3) % key_len]) 
            self.p_boxes[i] = self.p_boxes[i] ^ val 
            index = index + 4 
 
        # For the chaining process 
        l, r = 0, 0 
 
        # Begin chain replacing the p-boxes 
        for i in range (0, len (self.p_boxes), 2): 
            l, r = self.cipher (l, r, self.ENCRYPT) 
            self.p_boxes[i] = l 
            self.p_boxes[i + 1] = r 
 
        # Chain replace the s-boxes 
        for i in range (len (self.s_boxes)): 
            for j in range (0, len (self.s_boxes[i]), 2): 
                l, r = self.cipher (l, r, self.ENCRYPT) 
                self.s_boxes[i][j] = l 
                self.s_boxes[i][j + 1] = r 
 
        self.initCTR() 
 
 
    def cipher (self, xl, xr, direction): 
        """Encryption primitive""" 
        if direction == self.ENCRYPT: 
            for i in range (16): 
                xl = xl ^ self.p_boxes[i] 
                xr = self.__round_func (xl) ^ xr 
                xl, xr = xr, xl 
            xl, xr = xr, xl 
            xr = xr ^ self.p_boxes[16] 
            xl = xl ^ self.p_boxes[17] 
        else: 
            for i in range (17, 1, -1): 
                xl = xl ^ self.p_boxes[i] 
                xr = self.__round_func (xl) ^ xr 
                xl, xr = xr, xl 
            xl, xr = xr, xl 
            xr = xr ^ self.p_boxes[1] 
            xl = xl ^ self.p_boxes[0] 
        return xl, xr 
 
 
    def __round_func (self, xl): 
        a = (xl & 0xFF000000) >> 24 
        b = (xl & 0x00FF0000) >> 16 
        c = (xl & 0x0000FF00) >> 8 
        d = xl & 0x000000FF 
 
        # Perform all ops as longs then and out the last 32-bits to 
        # obtain the integer 
        f = (long (self.s_boxes[0][a]) + long (self.s_boxes[1][b])) % self.modulus 
        f = f ^ long (self.s_boxes[2][c]) 
        f = f + long (self.s_boxes[3][d]) 
        f = (f % self.modulus) & 0xFFFFFFFF 
 
        return f 
 
 
    def encrypt (self, data): 
        if not len (data) == 8: 
            raise RuntimeError, "Attempted to encrypt data of invalid block length: %s" % len(data) 
 
        # Use big endianess since that's what everyone else uses 
        xl = ord (data[3]) | (ord (data[2]) << 8) | (ord (data[1]) << 16) | (ord (data[0]) << 24) 
        xr = ord (data[7]) | (ord (data[6]) << 8) | (ord (data[5]) << 16) | (ord (data[4]) << 24) 
 
        cl, cr = self.cipher (xl, xr, self.ENCRYPT) 
        chars = ''.join ([ 
            chr ((cl >> 24) & 0xFF), chr ((cl >> 16) & 0xFF), chr ((cl >> 8) & 0xFF), chr (cl & 0xFF), 
            chr ((cr >> 24) & 0xFF), chr ((cr >> 16) & 0xFF), chr ((cr >> 8) & 0xFF), chr (cr & 0xFF) 
        ]) 
        return chars 
 
 
    def decrypt (self, data): 
        if not len (data) == 8: 
            raise RuntimeError, "Attempted to encrypt data of invalid block length: %s" % len(data) 
 
        # Use big endianess since that's what everyone else uses 
        cl = ord (data[3]) | (ord (data[2]) << 8) | (ord (data[1]) << 16) | (ord (data[0]) << 24) 
        cr = ord (data[7]) | (ord (data[6]) << 8) | (ord (data[5]) << 16) | (ord (data[4]) << 24) 
 
        xl, xr = self.cipher (cl, cr, self.DECRYPT) 
        chars = ''.join ([ 
            chr ((xl >> 24) & 0xFF), chr ((xl >> 16) & 0xFF), chr ((xl >> 8) & 0xFF), chr (xl & 0xFF), 
            chr ((xr >> 24) & 0xFF), chr ((xr >> 16) & 0xFF), chr ((xr >> 8) & 0xFF), chr (xr & 0xFF) 
        ]) 
        return chars 
 
 
    # ==== CBC Mode ==== 
    def initCBC(self, iv=0): 
        """Initializes CBC mode of the cypher""" 
        assert struct.calcsize("Q") == self.block_size() 
        self.cbc_iv = struct.pack("Q", iv) 
 
 
    def encryptCBC(self, data): 
        """ 
        Encrypts a buffer of data using CBC mode. Multiple successive buffers 
        (belonging to the same logical stream of buffers) can be encrypted 
        with this method one after the other without any intermediate work. 
        Each buffer must be a multiple of 8-octets (64-bits) in length. 
        """ 
        if type(data) != types.StringType: 
            raise RuntimeError, "Can only work on 8-bit strings" 
        if (len(data) % 8) != 0: 
            raise RuntimeError, "Can only work with data in 64-bit multiples in CBC mode" 
 
        xor = lambda t: ord(t[0]) ^ ord(t[1]) 
        result = '' 
        block_size = self.block_size() 
        for i in range(0, len(data), block_size): 
            p_block = data[i:i+block_size] 
            pair = zip(p_block, self.cbc_iv) 
            j_block = ''.join(map(chr, map(xor, pair))) 
            c_block = self.encrypt(j_block) 
            result += c_block 
            self.cbc_iv = c_block 
        return result 
 
 
    def decryptCBC(self, data): 
        if type(data) != types.StringType: 
            raise RuntimeError, "Can only work on 8-bit strings" 
        if (len(data) % 8) != 0: 
            raise RuntimeError, "Can only work with data in 64-bit multiples in CBC mode" 
 
        xor = lambda t: ord(t[0]) ^ ord(t[1]) 
        result = '' 
        block_size = self.block_size() 
        for i in range(0, len(data), block_size): 
            c_block = data[i:i+block_size] 
            j_block = self.decrypt(c_block) 
            pair = zip(j_block, self.cbc_iv) 
            p_block = ''.join(map(chr, map(xor, pair))) 
            result += p_block 
            self.cbc_iv = c_block 
        return result 
 
 
    # ==== CTR Mode ==== 
    def initCTR(self, iv=0): 
        """Initializes CTR mode of the cypher""" 
        assert struct.calcsize("Q") == self.block_size() 
        self.ctr_iv = iv 
        self._calcCTRBUF() 
 
 
    def _calcCTRBUF(self): 
        """Calculates one block of CTR keystream""" 
        self.ctr_cks = self.encrypt(struct.pack("Q", self.ctr_iv)) # keystream block 
        self.ctr_iv += 1 
        self.ctr_pos = 0 
 
 
    def _nextCTRByte(self): 
        """Returns one byte of CTR keystream""" 
        b = ord(self.ctr_cks[self.ctr_pos]) 
        self.ctr_pos += 1 
        if self.ctr_pos >= len(self.ctr_cks): 
            self._calcCTRBUF() 
        return b 
 
 
    def encryptCTR(self, data): 
        """ 
        Encrypts a buffer of data with CTR mode. Multiple successive buffers 
        (belonging to the same logical stream of buffers) can be encrypted 
        with this method one after the other without any intermediate work. 
        """ 
        if type(data) != types.StringType: 
            raise RuntimeException, "Can only work on 8-bit strings" 
        result = [] 
        for ch in data: 
            result.append(chr(ord(ch) ^ self._nextCTRByte())) 
        return "".join(result) 
 
 
    def decryptCTR(self, data): 
        return self.encryptCTR(data) 
 
 
    def block_size(self): 
        return 8 
 
 
    def key_length(self): 
        return 56 
 
 
    def key_bits(self): 
        return 56 * 8 
 
    @staticmethod 
    def testVectors(): 
        import binascii 
        # for more vectors see http://www.schneier.com/code/vectors.txt 
        vectors = ( 
            ('0000000000000000',        '0000000000000000',        '4EF997456198DD78'), 
            ('FFFFFFFFFFFFFFFF',        'FFFFFFFFFFFFFFFF',        '51866FD5B85ECB8A'), 
            ('3000000000000000',        '1000000000000001',        '7D856F9A613063F2'), 
            ('1111111111111111',        '1111111111111111',        '2466DD878B963C9D'), 
            ('49E95D6D4CA229BF',        '02FE55778117F12A',        'CF9C5D7A4986ADB5'), 
            ('E0FEE0FEF1FEF1FE',        '0123456789ABCDEF',        'C39E072D9FAC631D'), 
            ('07A7137045DA2A16',        '3BDD119049372802',        '2EEDDA93FFD39C79'), 
        ) 
        ok = True 
        for v in vectors: 
            c = Blowfish(binascii.a2b_hex(v[0])) 
            e = binascii.b2a_hex(c.encrypt(binascii.a2b_hex(v[1]))).upper() 
            if e != v[2]: 
                print "VECTOR TEST FAIL: expecting %s, got %s" % (repr(v), e) 
                ok = False 
        return ok 
 
         
 
############################################################## 
# Module testing 
 
if __name__ == '__main__': 
    if not Blowfish.testVectors(): 
        print "WARNING: The implementation doesn't pass algorithm test vectors!" 
    else: 
        print "The implementation passes algorithm test vectors (ECB)." 
 
    key = 'This is a test key' 
    cipher = Blowfish (key) 
 
    print "Testing encryption:" 
    xl = 123456 
    xr = 654321 
    print "/tPlain text: (%s, %s)" %(xl, xr) 
    cl, cr = cipher.cipher (xl, xr, cipher.ENCRYPT) 
    print "/tCrypted is: (%s, %s)" %(cl, cr) 
    dl, dr = cipher.cipher (cl, cr, cipher.DECRYPT) 
    print "/tUnencrypted is: (%s, %s)" %(dl, dr) 
 
    print "Testing block encrypt:" 
    text = 'testtest' 
    print "/tText:/t/t%s" %text 
    crypted = cipher.encrypt(text) 
    print "/tEncrypted:/t%s" % repr(crypted) 
    decrypted = cipher.decrypt(crypted) 
    print "/tDecrypted:/t%s" %decrypted 
     
    print "Testing CTR encrypt:" 
    cipher.initCTR() 
    text = "The quick brown fox jumps over the lazy dog" 
    print "/tText:/t/t", text 
    crypted = cipher.encryptCTR(text) 
    print "/tEncrypted:/t", repr(crypted) 
    cipher.initCTR() 
    decrypted = cipher.decryptCTR(crypted) 
    print "/tDecrypted:/t", decrypted 
 
    print "Testing CBC encrypt:" 
    cipher.initCBC() 
    text = "Owen's Ornery Old Oryx Obstructed Olga's Optics." 
    print "/tText:/t/t", text 
    crypted = cipher.encryptCBC(text) 
    print "/tEncrypted:/t", repr(crypted) 
    cipher.initCBC() 
    decrypted = cipher.decryptCBC(crypted) 
    print "/tDecrypted:/t", decrypted 
 
    print "Testing speed" 
    from time import time 
    t1 = time() 
    n = 0 
    tlen = 0 
    while True: 
        for i in xrange(1000): 
            tstr = "The quick brown fox jumps over the lazy dog %d" % i 
            enc = cipher.encryptCTR(tstr) 
            tlen += len(tstr) 
        n += 1000 
        t2 = time() 
        if t2 - t1 > 5: 
            break 
    t = t2 - t1 
    print "%d encryptions in %0.1f seconds: %0.1f enc/s, %0.1f bytes/s" % (n, t, n / t, tlen / t)

原创文章,作者:ItWorker,如若转载,请注明出处:https://blog.ytso.com/tech/pnotes/8081.html

(0)
上一篇 2021年7月18日 19:17
下一篇 2021年7月18日 19:17

相关推荐

发表回复

登录后才能评论