Python DES加密、解密

码表：desstruct.py

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)
ip_1=(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=[ [[14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7],
   [0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8],
   [4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0],
   [15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13]],
   [[15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10],
   [3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5],
   [0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15],
   [13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9]],
   [[10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8],
   [13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1],
   [13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7],
   [1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12]],
  [[7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15],
   [13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14,9],
   [10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4],
   [3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14]],
  [[2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9],
   [14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6],
   [4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14],
   [11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3]],
  [[12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11],
   [10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8],
   [9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6],
   [4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13]],
  [[4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1],
   [13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6],
   [1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2],
   [6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12]],
  [[13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7],
   [1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2],
   [7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8],
   [2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11]]]
pc1=(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, 33, 15,
    7, 62, 54, 46, 38, 30, 22,
   14, 6, 61, 53, 45, 37, 29,
   21, 13, 5, 28, 20, 12, 4);
pc2= (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)
d = ( 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1)

加密：des.py

# _*_ coding:utf-8 _*_
# !/usr/bin/env python
# Filename:des.py
from desstruct import *
import re

__all__ = ['desencode']


class DES():
    '''des 加密'''

    def __init__(self):
        pass

    # 加密
    def code(self, from_code, key, code_len, key_len):
        output = ""
        trun_len = 0
        # 将密文和**转换为二进制
        code_string = self._functionCharToA(from_code, code_len)
        code_key = self._functionCharToA(key, key_len)
        # 如果**长度不是16的整数倍则以增加0的方式变为16的整数倍
        if code_len % 16 != 0:
            real_len = (code_len / 16) * 16 + 16
        else:
            real_len = code_len
        if key_len % 16 != 0:
            key_len = (key_len / 16) * 16 + 16
        key_len *= 4
        # 每个16进制占4位
        trun_len = 4 * real_len
        # 对每64位进行一次加密
        for i in range(0, trun_len, 64):
            run_code = code_string[i:i + 64]
            l = i % key_len
            run_key = code_key[l:l + 64]
            # 64位明文、**初始置换
            run_code = self._codefirstchange(run_code)
            run_key = self._keyfirstchange(run_key)
            # 16次迭代
            for j in range(16):
                # 取出明文左右32位
                code_r = run_code[32:64]
                code_l = run_code[0:32]
                # 64左右交换
                run_code = code_r
                # 右边32位扩展置换
                code_r = self._functionE(code_r)
                # 获取本***
                key_l = run_key[0:28]
                key_r = run_key[28:56]
                key_l = key_l[d[j]:28] + key_l[0:d[j]]
                key_r = key_r[d[j]:28] + key_r[0:d[j]]
                run_key = key_l + key_r
                key_y = self._functionKeySecondChange(run_key)
                # 异或
                code_r = self._codeyihuo(code_r, key_y)
                # S盒代替/选择
                code_r = self._functionS(code_r)
                # P转换
                code_r = self._functionP(code_r)
                # 异或
                code_r = self._codeyihuo(code_l, code_r)
                run_code += code_r
            # 32互换
            code_r = run_code[32:64]
            code_l = run_code[0:32]
            run_code = code_r + code_l
            # 将二进制转换为16进制、逆初始置换
            output += self._functionCodeChange(run_code)
        return output

    # 异或
    def _codeyihuo(self, code, key):
        code_len = len(key)
        return_list = ''
        for i in range(code_len):
            if code[i] == key[i]:
                return_list += '0'
            else:
                return_list += '1'
        return return_list

    # 密文或明文初始置换
    def _codefirstchange(self, code):
        changed_code = ''
        for i in range(64):
            changed_code += code[ip[i] - 1]
        return changed_code

    # **初始置换
    def _keyfirstchange(self, key):
        changed_key = ''
        for i in range(56):
            changed_key += key[pc1[i] - 1]
        return changed_key

    # 逆初始置换
    def _functionCodeChange(self, code):
        lens = len(code) / 4
        return_list = ''
        for i in range(lens):
            list = ''
            for j in range(4):
                list += code[ip_1[i * 4 + j] - 1]
            return_list += "%x" % int(list, 2)
        return return_list

    # 扩展置换
    def _functionE(self, code):
        return_list = ''
        for i in range(48):
            return_list += code[e[i] - 1]
        return return_list
        # 置换P

    def _functionP(self, code):
        return_list = ''
        for i in range(32):
            return_list += code[p[i] - 1]
        return return_list

    # S盒代替选择置换
    def _functionS(self, key):
        return_list = ''
        for i in range(8):
            row = int(str(key[i * 6]) + str(key[i * 6 + 5]), 2)
            raw = int(str(key[i * 6 + 1]) + str(key[i * 6 + 2]) + str(key[i * 6 + 3]) + str(key[i * 6 + 4]), 2)
            return_list += self._functionTos(s[i][row][raw], 4)
        return return_list

    # **置换选择2
    def _functionKeySecondChange(self, key):
        return_list = ''
        for i in range(48):
            return_list += key[pc2[i] - 1]
        return return_list

    # 将十六进制转换为二进制字符串
    def _functionCharToA(self, code, lens):
        return_code = ''
        lens = lens % 16
        for key in code:
            code_ord = int(key, 16)
            return_code += self._functionTos(code_ord, 4)
        if lens != 0:
            return_code += '0' * (16 - lens) * 4
        return return_code

    # 二进制转换
    def _functionTos(self, o, lens):
        return_code = ''
        for i in range(lens):
            return_code = str(o >> i & 1) + return_code
        return return_code


# 将unicode字符转换为16进制
def tohex(string):
    return_string = ''
    for i in string:
        return_string += "%02x" % ord(i)
    return return_string


def tounicode(string):
    return_string = ''
    string_len = len(string)
    for i in range(0, string_len, 2):
        return_string += chr(int(string[i:i + 2], 16))
    return return_string


# 入口函数
def desencode(from_code, key):
    # 转换为16进制
    from_code = tohex(from_code)
    key = tohex(key)
    des = DES()
    key_len = len(key)
    string_len = len(from_code)
    if string_len < 1 or key_len < 1:
        print 'error input'
        return False
    key_code = des.code(from_code, key, string_len, key_len)
    return key_code



if __name__ == '__main__':
    print 'DES加密后结果为：',desencode('chenyongyan', '<L;*3Md7')

解密：undes.py

#_*_coding:utf-8_*_
#!/usr/bin/env python
#Filename:des.py
from desstruct import *
import re


__all__=['desdecode']


class DES():


    def __init__(self):
        pass

    def decode(self, string, key, key_len, string_len):
        output = ""
        trun_len = 0
        num = 0
        # 将密文转换为二进制
        code_string = self._functionCharToA(string, string_len)
        # 获取字**
        code_key = self._getkey(key, key_len)
        # 如果**长度不是16的整数倍则以增加0的方式变为16的整数倍
        real_len = (key_len / 16) + 1 if key_len % 16 != 0 else key_len / 16
        trun_len = string_len * 4
        # 对每64位进行一次加密
        for i in range(0, trun_len, 64):
            run_code = code_string[i:i + 64]
            run_key = code_key[num % real_len]
            # 64位明文初始置换
            run_code = self._codefirstchange(run_code)
            # 16次迭代
            for j in range(16):
                code_r = run_code[32:64]
                code_l = run_code[0:32]
                # 64左右交换
                run_code = code_r
                # 右边32位扩展置换
                code_r = self._functionE(code_r)
                # 获取本***
                key_y = run_key[15 - j]
                # 异或
                code_r = self._codeyihuo(code_r, key_y)
                # S盒代替/选择
                code_r = self._functionS(code_r)
                # P转换
                code_r = self._functionP(code_r)
                # 异或
                code_r = self._codeyihuo(code_l, code_r)
                run_code += code_r
            num += 1
            # 32互换
            code_r = run_code[32:64]
            code_l = run_code[0:32]
            run_code = code_r + code_l
            # 将二进制转换为16进制、逆初始置换
            output += self._functionCodeChange(run_code)
        return output

    # 获取子**
    def _getkey(self, key, key_len):
        # 将**转换为二进制
        code_key = self._functionCharToA(key, key_len)
        a = [''] * 16
        real_len = (key_len / 16) * 16 + 16 if key_len % 16 != 0 else key_len
        b = [''] * (real_len / 16)
        for i in range(real_len / 16):
            b[i] = a[:]
        num = 0
        trun_len = 4 * key_len
        for i in range(0, trun_len, 64):
            run_key = code_key[i:i + 64]
            run_key = self._keyfirstchange(run_key)
            for j in range(16):
                key_l = run_key[0:28]
                key_r = run_key[28:56]
                key_l = key_l[d[j]:28] + key_l[0:d[j]]
                key_r = key_r[d[j]:28] + key_r[0:d[j]]
                run_key = key_l + key_r
                key_y = self._functionKeySecondChange(run_key)
                b[num][j] = key_y[:]
            num += 1
        return b
        # 异或

    def _codeyihuo(self, code, key):
        code_len = len(key)
        return_list = ''
        for i in range(code_len):
            if code[i] == key[i]:
                return_list += '0'
            else:
                return_list += '1'
        return return_list

    # 密文或明文初始置换
    def _codefirstchange(self, code):
        changed_code = ''
        for i in range(64):
            changed_code += code[ip[i] - 1]
        return changed_code

    # **初始置换
    def _keyfirstchange(self, key):
        changed_key = ''
        for i in range(56):
            changed_key += key[pc1[i] - 1]
        return changed_key

    # 逆初始置换
    def _functionCodeChange(self, code):
        return_list = ''
        for i in range(16):
            list = ''
            for j in range(4):
                list += code[ip_1[i * 4 + j] - 1]
            return_list += "%x" % int(list, 2)
        return return_list

    # 扩展置换
    def _functionE(self, code):
        return_list = ''
        for i in range(48):
            return_list += code[e[i] - 1]
        return return_list
        # 置换P

    def _functionP(self, code):
        return_list = ''
        for i in range(32):
            return_list += code[p[i] - 1]
        return return_list

    # S盒代替选择置换
    def _functionS(self, key):
        return_list = ''
        for i in range(8):
            row = int(str(key[i * 6]) + str(key[i * 6 + 5]), 2)
            raw = int(str(key[i * 6 + 1]) + str(key[i * 6 + 2]) + str(key[i * 6 + 3]) + str(key[i * 6 + 4]), 2)
            return_list += self._functionTos(s[i][row][raw], 4)
        return return_list

    # **置换选择2
    def _functionKeySecondChange(self, key):
        return_list = ''
        for i in range(48):
            return_list += key[pc2[i] - 1]
        return return_list

    # 将十六进制转换为二进制字符串
    def _functionCharToA(self, code, lens):
        return_code = ''
        lens = lens % 16
        for key in code:
            code_ord = int(key, 16)
            return_code += self._functionTos(code_ord, 4)
        if lens != 0:
            return_code += '0' * (16 - lens) * 4
        return return_code

    # 二进制转换
    def _functionTos(self, o, lens):
        return_code = ''
        for i in range(lens):
            return_code = str(o >> i & 1) + return_code
        return return_code
    # 将unicode字符转换为16进制


def tohex(string):
    return_string = ''
    for i in string:
        return_string += "%02x" % ord(i)
    return return_string


def tounicode(string):
    return_string = ''
    string_len = len(string)
    for i in range(0, string_len, 2):
        return_string += chr(int(string[i:i + 2], 16))
    return return_string
    # 入口函数


def desdecode(from_code, key):
    key = tohex(key)
    des = DES()
    key_len = len(key)
    string_len = len(from_code)
    if string_len % 16 != 0:
        return False
    if string_len < 1 or key_len < 1:
        return False
    key_code = des.decode(from_code, key, key_len, string_len)
    return tounicode(key_code)



if __name__ == '__main__':
    print 'DES解密后结果为：',desdecode('2b68df510e4059d538a849ca1c73da43','<L;*3Md7')