# python中DES算法加密和解密实例介绍

python中DES算法加密和解密是如何来实现的呢？下面的内容将会通过具体的实例来演示python中DES算法加密和解密的实现方法及相关技巧：

 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180 #coding=utf-8 from functools import partial import base64 class DES(object):   """   DES加密算法   interface: input_key(s, base=10), encode(s), decode(s)   """   __ip = [     58,50,42,34,26,18,10,2,60,52,44,36,28,20,12,4,     62,54,46,38,30,22,14,6,64,56,48,40,32,24,16,8,     57,49,41,33,25,17, 9,1,59,51,43,35,27,19,11,3,     61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7,   ]   __ip1 = [     40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,     38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,     36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,     34,2,42,10,50,18,58,26,33,1,41, 9,49,17,57,25,   ]   __e = [     32, 1, 2, 3, 4, 5,     4 , 5, 6, 7, 8, 9,     8 , 9,10,11,12,13,     12,13,14,15,16,17,     16,17,18,19,20,21,     20,21,22,23,24,25,     24,25,26,27,28,29,     28,29,30,31,32, 1,   ]   __p = [     16, 7,20,21,29,12,28,17,     1 ,15,23,26, 5,18,31,10,     2 ,8 ,24,14,32,27, 3, 9,     19,13,30, 6,22,11, 4,25,   ]   __s = [     [     0xe,0x4,0xd,0x1,0x2,0xf,0xb,0x8,0x3,0xa,0x6,0xc,0x5,0x9,0x0,0x7,     0x0,0xf,0x7,0x4,0xe,0x2,0xd,0x1,0xa,0x6,0xc,0xb,0x9,0x5,0x3,0x8,     0x4,0x1,0xe,0x8,0xd,0x6,0x2,0xb,0xf,0xc,0x9,0x7,0x3,0xa,0x5,0x0,     0xf,0xc,0x8,0x2,0x4,0x9,0x1,0x7,0x5,0xb,0x3,0xe,0xa,0x0,0x6,0xd,     ],     [     0xf,0x1,0x8,0xe,0x6,0xb,0x3,0x4,0x9,0x7,0x2,0xd,0xc,0x0,0x5,0xa,     0x3,0xd,0x4,0x7,0xf,0x2,0x8,0xe,0xc,0x0,0x1,0xa,0x6,0x9,0xb,0x5,     0x0,0xe,0x7,0xb,0xa,0x4,0xd,0x1,0x5,0x8,0xc,0x6,0x9,0x3,0x2,0xf,     0xd,0x8,0xa,0x1,0x3,0xf,0x4,0x2,0xb,0x6,0x7,0xc,0x0,0x5,0xe,0x9,     ],     [     0xa,0x0,0x9,0xe,0x6,0x3,0xf,0x5,0x1,0xd,0xc,0x7,0xb,0x4,0x2,0x8,     0xd,0x7,0x0,0x9,0x3,0x4,0x6,0xa,0x2,0x8,0x5,0xe,0xc,0xb,0xf,0x1,     0xd,0x6,0x4,0x9,0x8,0xf,0x3,0x0,0xb,0x1,0x2,0xc,0x5,0xa,0xe,0x7,     0x1,0xa,0xd,0x0,0x6,0x9,0x8,0x7,0x4,0xf,0xe,0x3,0xb,0x5,0x2,0xc,     ],     [     0x7,0xd,0xe,0x3,0x0,0x6,0x9,0xa,0x1,0x2,0x8,0x5,0xb,0xc,0x4,0xf,     0xd,0x8,0xb,0x5,0x6,0xf,0x0,0x3,0x4,0x7,0x2,0xc,0x1,0xa,0xe,0x9,     0xa,0x6,0x9,0x0,0xc,0xb,0x7,0xd,0xf,0x1,0x3,0xe,0x5,0x2,0x8,0x4,     0x3,0xf,0x0,0x6,0xa,0x1,0xd,0x8,0x9,0x4,0x5,0xb,0xc,0x7,0x2,0xe,     ],     [     0x2,0xc,0x4,0x1,0x7,0xa,0xb,0x6,0x8,0x5,0x3,0xf,0xd,0x0,0xe,0x9,     0xe,0xb,0x2,0xc,0x4,0x7,0xd,0x1,0x5,0x0,0xf,0xa,0x3,0x9,0x8,0x6,     0x4,0x2,0x1,0xb,0xa,0xd,0x7,0x8,0xf,0x9,0xc,0x5,0x6,0x3,0x0,0xe,     0xb,0x8,0xc,0x7,0x1,0xe,0x2,0xd,0x6,0xf,0x0,0x9,0xa,0x4,0x5,0x3,     ],     [     0xc,0x1,0xa,0xf,0x9,0x2,0x6,0x8,0x0,0xd,0x3,0x4,0xe,0x7,0x5,0xb,     0xa,0xf,0x4,0x2,0x7,0xc,0x9,0x5,0x6,0x1,0xd,0xe,0x0,0xb,0x3,0x8,     0x9,0xe,0xf,0x5,0x2,0x8,0xc,0x3,0x7,0x0,0x4,0xa,0x1,0xd,0xb,0x6,     0x4,0x3,0x2,0xc,0x9,0x5,0xf,0xa,0xb,0xe,0x1,0x7,0x6,0x0,0x8,0xd,     ],     [     0x4,0xb,0x2,0xe,0xf,0x0,0x8,0xd,0x3,0xc,0x9,0x7,0x5,0xa,0x6,0x1,     0xd,0x0,0xb,0x7,0x4,0x9,0x1,0xa,0xe,0x3,0x5,0xc,0x2,0xf,0x8,0x6,     0x1,0x4,0xb,0xd,0xc,0x3,0x7,0xe,0xa,0xf,0x6,0x8,0x0,0x5,0x9,0x2,     0x6,0xb,0xd,0x8,0x1,0x4,0xa,0x7,0x9,0x5,0x0,0xf,0xe,0x2,0x3,0xc,     ],     [     0xd,0x2,0x8,0x4,0x6,0xf,0xb,0x1,0xa,0x9,0x3,0xe,0x5,0x0,0xc,0x7,     0x1,0xf,0xd,0x8,0xa,0x3,0x7,0x4,0xc,0x5,0x6,0xb,0x0,0xe,0x9,0x2,     0x7,0xb,0x4,0x1,0x9,0xc,0xe,0x2,0x0,0x6,0xa,0xd,0xf,0x3,0x5,0x8,     0x2,0x1,0xe,0x7,0x4,0xa,0x8,0xd,0xf,0xc,0x9,0x0,0x3,0x5,0x6,0xb,     ],   ]   __k1 = [     57,49,41,33,25,17, 9,     1 ,58,50,42,34,26,18,     10, 2,59,51,43,35,27,     19,11, 3,60,52,44,36,     63,55,47,39,31,23,15,     7 ,62,54,46,38,30,22,     14, 6,61,53,45,37,29,     21,13, 5,28,20,12, 4,   ]   __k2 = [     14,17,11,24, 1, 5, 3,28,     15, 6,21,10,23,19,12, 4,     26, 8,16, 7,27,20,13, 2,     41,52,31,37,47,55,30,40,     51,45,33,48,44,49,39,56,     34,53,46,42,50,36,29,32,   ]   __k0 = [     1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1,   ]   __hex_bin = {     '0':'0000','1':'0001','2':'0010','3':'0011',     '4':'0100','5':'0101','6':'0110','7':'0111',     '8':'1000','9':'1001','a':'1010','b':'1011',     'c':'1100','d':'1101','e':'1110','f':'1111',     ' ':'0000'   }   __re = lambda t, s: ''.join(s[i-1] for i in t)   __IP = partial(__re, __ip)   __IP1 = partial(__re, __ip1)   __E = partial(__re, __e)   __P = partial(__re, __p)   __K1 = partial(__re, __k1)   __K2 = partial(__re, __k2)   __B = partial( lambda hex_bin, s: ''.join(hex_bin[w]     for w in ''.join('%2x' % ord(w) for w in s))     , __hex_bin)   __DB = partial( lambda s: ''.join(chr(int(s[i:i+8], 2)) for i in range(0, len(s), 8)))   __S = partial( lambda hex_bin, __s, s: ''.join(hex_bin['%x' % __s[i][     int(s[i*6]+s[i*6+5], 2)*16 + int(s[i*6+1:i*6+5], 2)]] for i in range(8))     , __hex_bin, __s)   __F = partial( lambda s, k: ''.join('0' if s[i]==k[i] else '1' for i in range(len(s))))   __K0 = partial( lambda k0, K2, k: map(K2,     (k[k0[i]:28]+k[0:k0[i]] + k[k0[i]+28:56]+k[28:k0[i]+28] for i in range(16)))     , __k0, __K2)   __K = partial( lambda K1, K0, k: K0(K1(k))     , __K1, __K0)   def __init__(self):     pass   def input_key(self, key, base=10):     if base == 2:       pass     elif base == 16:       key = ''.join(self.__class__.__hex_bin[w] for w in key)     else:       key = self.__class__.__B(key)     self.__k = self.__class__.__K(key)   def __code(self, s, k):     s = self.__IP(s)     l, r = s[0:32], s[32:64]     for i in range(16):       r_t = r       r = self.__E(r)       r = self.__F(r, k[i])       r = self.__S(r)       r = self.__P(r)       r = self.__F(r, l)       l = r_t     return self.__class__.__IP1(r+l)   def encode(self, s):     a = ''     s += ' ' * ((8-len(s)%8)%8)     for i in range(0, len(s), 8):       before = self.__class__.__B(s[i:i+8])       after = self.__code(before, self.__k)       a += '%16x' % int(after, 2)     return ''.join(w if w!=' ' else '0' for w in a)   def decode(self, s):     a = ''     s.lower()     for i in range(0, len(s), 16):       before = ''.join(self.__class__.__hex_bin[s[j]] for j in range(i, i+16))       after = self.__code(before, self.__k[::-1])       a += self.__class__.__DB(after)     return a.rstrip().decode('utf-8') if __name__ == '__main__':   d = DES()   d.input_key('123456789')   s = '再来一段中文'   a = d.encode(s)   print a   b = d.decode(a)   print b

python中DES算法加密和解密就是这样，欢迎大家参考。。。。