python实现DES加密解密方法实例详解
本文实例讲述了python实现DES加密解密方法。分享给大家供大家参考。具体分析如下：
实现功能：加密中文等字符串
密钥与明文可以不等长
这里只贴代码，加密过程可以自己百度，此处python代码没有优化
1.desstruct.pyDES加密中要使用的结构体
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)
2.des.py加密文件
#_*_coding:utf-8_*_
#!/usr/bin/envpython
#Filename:des.py
fromdesstructimport*
importre
__all__=['desencode']
classDES():
'''des加密'''
def__init__(self):
pass
#加密
defcode(self,from_code,key,code_len,key_len):
output=""
trun_len=0
#将密文和密钥转换为二进制
code_string=self._functionCharToA(from_code,code_len)
code_key=self._functionCharToA(key,key_len)
#如果密钥长度不是16的整数倍则以增加0的方式变为16的整数倍
ifcode_len%16!=0:
real_len=(code_len/16)*16+16
else:
real_len=code_len
ifkey_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
foriinrange(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、密钥初始置换
run_code=self._codefirstchange(run_code)
run_key=self._keyfirstchange(run_key)
#16次迭代
forjinrange(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)
#获取本轮子密钥
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)
returnoutput
#异或
def_codeyihuo(self,code,key):
code_len=len(key)
return_list=''
foriinrange(code_len):
ifcode[i]==key[i]:
return_list+='0'
else:
return_list+='1'
returnreturn_list
#密文或明文初始置换
def_codefirstchange(self,code):
changed_code=''
foriinrange(64):
changed_code+=code[ip[i]-1]
returnchanged_code
#密钥初始置换
def_keyfirstchange(self,key):
changed_key=''
foriinrange(56):
changed_key+=key[pc1[i]-1]
returnchanged_key
#逆初始置换
def_functionCodeChange(self,code):
lens=len(code)/4
return_list=''
foriinrange(lens):
list=''
forjinrange(4):
list+=code[ip_1[i*4+j]-1]
return_list+="%x"%int(list,2)
returnreturn_list
#扩展置换
def_functionE(self,code):
return_list=''
foriinrange(48):
return_list+=code[e[i]-1]
returnreturn_list
#置换P
def_functionP(self,code):
return_list=''
foriinrange(32):
return_list+=code[p[i]-1]
returnreturn_list
#S盒代替选择置换
def_functionS(self,key):
return_list=''
foriinrange(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)
returnreturn_list
#密钥置换选择2
def_functionKeySecondChange(self,key):
return_list=''
foriinrange(48):
return_list+=key[pc2[i]-1]
returnreturn_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
forkeyincode:
code_ord=int(key,16)
return_code+=self._functionTos(code_ord,4)
iflens!=0:
return_code+='0'*(16-lens)*4
returnreturn_code
#二进制转换
def_functionTos(self,o,lens):
return_code=''
foriinrange(lens):
return_code=str(o>>i&1)+return_code
returnreturn_code
#将unicode字符转换为16进制
deftohex(string):
return_string=''
foriinstring:
return_string+="%02x"%ord(i)
returnreturn_string
deftounicode(string):
return_string=''
string_len=len(string)
foriinrange(0,string_len,2):
return_string+=chr(int(string[i:i+2],16))
returnreturn_string
#入口函数
defdesencode(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)
ifstring_len<1orkey_len<1:
print'errorinput'
returnFalse
key_code=des.code(from_code,key,string_len,key_len)
returnkey_code
#测试
if__name__=='__main__':
printdesencode('我是12345678刘就是我abcdwfd','0f1571c947刘')
#返回密文为:84148584371a6a1fe99e1da0ce1e34649b88ed15098e8aa4b8eb0bf24885c658
3.解密文件
#_*_coding:utf-8_*_
#!/usr/bin/envpython
#Filename:des.py
fromdesstructimport*
importre
__all__=['desdecode']
classDES():
'''解密函数，DES加密与解密的方法相差不大
只是在解密的时候所用的子密钥与加密的子密钥相反
'''
def__init__(self):
pass
defdecode(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)
#获取字密钥
code_key=self._getkey(key,key_len)
#如果密钥长度不是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)+1ifkey_len%16!=0elsekey_len/16
trun_len=string_len*4
#对每64位进行一次加密
foriinrange(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
forjinrange(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)
#获取本轮子密钥
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)
returnoutput
#获取子密钥
def_getkey(self,key,key_len):
#将密钥转换为二进制
code_key=self._functionCharToA(key,key_len)
a=['']*16
real_len=(key_len/16)*16+16ifkey_len%16!=0elsekey_len
b=['']*(real_len/16)
foriinrange(real_len/16):
b[i]=a[:]
num=0
trun_len=4*key_len
foriinrange(0,trun_len,64):
run_key=code_key[i:i+64]
run_key=self._keyfirstchange(run_key)
forjinrange(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
returnb
#异或
def_codeyihuo(self,code,key):
code_len=len(key)
return_list=''
foriinrange(code_len):
ifcode[i]==key[i]:
return_list+='0'
else:
return_list+='1'
returnreturn_list
#密文或明文初始置换
def_codefirstchange(self,code):
changed_code=''
foriinrange(64):
changed_code+=code[ip[i]-1]
returnchanged_code
#密钥初始置换
def_keyfirstchange(self,key):
changed_key=''
foriinrange(56):
changed_key+=key[pc1[i]-1]
returnchanged_key
#逆初始置换
def_functionCodeChange(self,code):
return_list=''
foriinrange(16):
list=''
forjinrange(4):
list+=code[ip_1[i*4+j]-1]
return_list+="%x"%int(list,2)
returnreturn_list
#扩展置换
def_functionE(self,code):
return_list=''
foriinrange(48):
return_list+=code[e[i]-1]
returnreturn_list
#置换P
def_functionP(self,code):
return_list=''
foriinrange(32):
return_list+=code[p[i]-1]
returnreturn_list
#S盒代替选择置换
def_functionS(self,key):
return_list=''
foriinrange(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)
returnreturn_list
#密钥置换选择2
def_functionKeySecondChange(self,key):
return_list=''
foriinrange(48):
return_list+=key[pc2[i]-1]
returnreturn_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
forkeyincode:
code_ord=int(key,16)
return_code+=self._functionTos(code_ord,4)
iflens!=0:
return_code+='0'*(16-lens)*4
returnreturn_code
#二进制转换
def_functionTos(self,o,lens):
return_code=''
foriinrange(lens):
return_code=str(o>>i&1)+return_code
returnreturn_code
#将unicode字符转换为16进制
deftohex(string):
return_string=''
foriinstring:
return_string+="%02x"%ord(i)
returnreturn_string
deftounicode(string):
return_string=''
string_len=len(string)
foriinrange(0,string_len,2):
return_string+=chr(int(string[i:i+2],16))
returnreturn_string
#入口函数
defdesdecode(from_code,key):
key=tohex(key)
des=DES()
key_len=len(key)
string_len=len(from_code)
ifstring_len%16!=0:
returnFalse
ifstring_len<1orkey_len<1:
returnFalse
key_code=des.decode(from_code,key,key_len,string_len)
returntounicode(key_code)
#测试
if__name__=='__main__':
printdesdecode('84148584371a6a1fe99e1da0ce1e34649b88ed15098e8aa4b8eb0bf24885c658','0f1571c947刘'
解密后为:我是12345678刘就是我abcdwfd
PythonDES加密解密，就是大家所谓想要的那个非常快速的方法
这个要借助Crypto.Cipher这个插件来实现的，引用后只需要写如下代码即可
fromCrypto.CipherimportDES
classMyDESCrypt:
key=chr(11)+chr(11)+chr(11)+chr(11)+chr(11)+chr(11)+chr(11)+chr(11)
iv=chr(22)+chr(22)+chr(22)+chr(22)+chr(22)+chr(22)+chr(22)+chr(22)
def__init__(self,key='',iv=''):
iflen(key)>0:
self.key=key
iflen(iv)>0:
self.iv=iv
defecrypt(self,ecryptText):
try:
cipherX=DES.new(self.key,DES.MODE_CBC,self.iv)
pad=8-len(ecryptText)%8
padStr=""
foriinrange(pad):
padStr=padStr+chr(pad)
ecryptText=ecryptText+padStr
x=cipherX.encrypt(ecryptText)
returnx.encode('hex_codec').upper()
except:
return""
defdecrypt(self,decryptText):
try:
cipherX=DES.new(self.key,DES.MODE_CBC,self.iv)
str=decryptText.decode('hex_codec')
y=cipherX.decrypt(str)
returny[0:ord(y[len(y)-1])*-1]
except:
return""
建议大家可以结合一些插件使用，更方便与快捷
希望本文所述对大家的Python程序设计有所帮助。