1、简述
1)、输入 64 位明文数据，并进行初始置换 IP；
2)、在初始置换 IP 后，明文数据再被分为左右两部分，每部分 32 位，以 L0，
R0 表示；
3)、在密钥的控制下，经过 16 轮运算(f)；
4)、16 轮后，左、右两部分交换，并连接再一起，再进行逆置换；
5)、输出 64 位密文。
以下时可能用到的参数：
key：8 个字节共 64 位的工作密钥
data：8 个字节共 64 位的需要被加密或被解密的数据
mode：DES 工作方式，加密或者解密
2、简单的python实现（非pyDES）
'''密钥K生成模块'''
MaxTime = 16
#生成子密钥的置换表1，将64位的密钥转换为56位
key_table1=[ 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 ]
#生成子密钥的置换表2，将56位的密钥转换为48位
key_table2=[ 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 ]
def Listmove(l, step): #将列表中的元素循环左移
return l[step:] + l[:step]
def Subkey(key): #生成子密钥
keyresult = []
key0 = [0 for i in range(56)]
for i in range(len(key_table1)):
key0[i] = key[key_table1[i]-1]
#生成16个密钥
for i in range(MaxTime):
key1 = [0 for i in range(48)]
#确定每次左移的步数
if (i == 0 or i == 1 or i == 8 or i == 15):
step = 1
else:
step = 2
#分成两组
tmp1 = key0[0:28]
tmp2 = key0[28:56]
#循环左移
tmp1 = Listmove(tmp1, step)
tmp2 = Listmove(tmp2, step)
#左右连接
key0 = tmp1 + tmp2
#置换选择
for i in range(len(key_table2)):
key1[i] = key0[key_table2[i]-1]
#生成密钥
keyresult.append(key1)
#返回的是一个集合包含了每次的密钥
return keyresult
import CreateSubkey as cs
import F_function as f
'''DES加密模块'''
# 十六进制转二进制比特串
def Hex2bin(text):
result = []
for i in range(len(text)):
result.extend(f.int2bit(int(text[i],16)))
return result
# 二进制比特串转十六进制
def bin2Hex(text):
result = []
q = len(text)//4
for i in range(q):
dec = int(text[4*i])*8 + int(text[4*i+1])*4 + int(text[4*i+2])*2 + int(text[4*i+3])*1
x = hex(dec)[2:].upper()
result.extend(x)
rs = ''.join(result)
return rs
# 按照DES算法的流程图进行运算
def Encryption(text, key):
keylist = cs.Subkey(keybit)
text1 = f.IP(text, 0) #IP置换
L = [text1[i] for i in range(32)]
R = [text1[i] for i in range(32,64)]
for i in range(16):
tmp = R
tmp = f.Extend(tmp)
tmp = f.Xor(tmp, keylist[i])
tmp = f.S_replace(tmp)
tmp = f.P_replace(tmp)
tmp = f.Xor(tmp, L)
L = R
R = tmp
L,R = R,L
ctext = L
ctext.extend(R)
ctext = f.IP(ctext, 1)
return bin2Hex(ctext)
if __name__ == '__main__':
plaintext = input('请输入用十六进制表示的明文：')
key = input('请输入用十六进制表示的密钥：')
ptext = Hex2bin(plaintext)
keybit = Hex2bin(key)
print('输出的密文为：' + Encryption(ptext, keybit))
import CreateSubkey as cs
import F_function as f
#十六进制转二进制比特串
def Hex2bin(text):
result = []
for i in range(len(text)):
result.extend(f.int2bit(int(text[i],16)))
return result
#二进制比特串转十六进制
def bin2Hex(text):
result = []
q = len(text)//4
for i in range(q):
dec = int(text[4*i])*8 + int(text[4*i+1])*4 + int(text[4*i+2])*2 + int(text[4*i+3])*1
x = hex(dec)[2:].upper()
result.extend(x)
rs = ''.join(result)
return rs
def Encryption(text, key):
keylist = cs.Subkey(keybit)
text1 = f.IP(text, 0) #IP置换
L = [text1[i] for i in range(32)]
R = [text1[i] for i in range(32,64)]
for i in range(16):
tmp = R
tmp = f.Extend(tmp)
tmp = f.Xor(tmp, keylist[15-i])
tmp = f.S_replace(tmp)
tmp = f.P_replace(tmp)
tmp = f.Xor(tmp, L)
L = R
R = tmp
L,R = R,L
ctext = L
ctext.extend(R)
ctext = f.IP(ctext, 1)
return bin2Hex(ctext)
if __name__ == '__main__':
plaintext = input('请输入用十六进制表示的密文：')
key = input('请输入用十六进制表示的密钥：')
ptext = Hex2bin(plaintext)
keybit = Hex2bin(key)
print('输出的明文为：' + Encryption(ptext, keybit))
'''F-function模块'''
MaxTime = 16
#IP置换表
IP_table=[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 ]
#逆IP置换表
Inv_IP_table=[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 ]
#S盒中的S1盒
S1=[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 ]
#S盒中的S2盒
S2=[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 ]
#S盒中的S3盒
S3=[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 ]
#S盒中的S4盒
S4=[ 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 ]
#S盒中的S5盒
S5=[ 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 ]
#S盒中的S6盒
S6=[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 ]
#S盒中的S7盒
S7=[ 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]
#S盒中的S8盒
S8=[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 ]
# S盒
S=[S1,S2,S3,S4,S5,S6,S7,S8]
#用于对数据进行扩展置换，将32bit数据扩展为48bit
extend_table=[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盒
P_table=[ 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 ]
def int2bit(n):#0~15整数转比特
a=[]
for i in range(0,4):
a.insert(0,str(n%2))
n=int(n/2)
return a
#IP置换部分，op为0表示正置换，op为1表示逆置换
def IP(text, op):
tmp = [0 for i in range(64)]
if op == 0:
for i in range(64):
tmp[i] = text[IP_table[i]-1]
return tmp
if op == 1:
for i in range(64):
tmp[i] = text[Inv_IP_table[i]-1]
return tmp
#进行扩展，将32位扩展为48位
def Extend(text):
extend = [0 for i in range(48)]
for i in range(48):
extend[i] = text[extend_table[i] - 1]
return extend
#S盒变换部分
def S_replace(text):
Sresult = [0 for k in range(32)]
for k in range(8):
row = 2*int(text[k*6]) + int(text[k*6+5])
column = 8*int(text[k*6+1]) + 4*int(text[k*6+2]) + 2*int(text[k*6+3]) + int(text[k*6+4])
tmp = S[k][row*16+column]
for i in range(4):
Sresult[4*k + i] = int2bit(tmp)[i]
return Sresult
#P置换部分
def P_replace(text):
Presult = [0 for i in range(32)]
for i in range(32):
Presult[i] = text[P_table[i]-1]
return Presult
#异或运算
def Xor(bit1, bit2):
Xorresult = [0 for i in range(len(bit1))]
for i in range(len(bit1)):
Xorresult[i] = str(int(bit1[i]) ^ int(bit2[i]))
return Xorresult
比较懒，先就这样了
