实现Des加密和解密的过程。
能处理16的倍数个16进制数(64bit)组成的明文和16个16进制数(64bit)组成的密钥的进行的加密解密。
ECB模式
from table import ip, ip_, pc1, pc2, table_e, table_p, s_box, left_rotations
def change_hex_to_bin(s):
a = bin(int(s, 16))[2:].upper().rjust(64, '0')
return a
def xor(left, right):
result = int(left, 2) ^ int(right, 2)
return bin(result)[2:].rjust(len(left), '0')
def translation(s, list_1):
result = ''
for i in list_1:
result += s[i-1]
return result
def move(lst, k):
k *= -1
len2 = len(lst)
ss = (lst[k:]+lst[:k]).rjust(len2, '0')
return str(ss)
def func_f(right, key):
result = translation(right, table_e)
result = xor(str(result), str(key))
result2 = ''
for i in range(0, len(result)-5, 6):
j = i // 6
r = int(result[i] + result[i + 5], 2)
n = int(result[i + 1] + result[i + 2] + result[i + 3] + result[i + 4], 2)
d = s_box[j][r * 16 + n]
result2 += bin(d)[2:].upper().rjust(4, '0')
result = translation(result2, table_p)
return str(result)
def generate_secret(key, r):
current_key_bin = bin(int(str(key), 16))[2:].rjust(64, '0')
current_key_bin = translation(current_key_bin, pc1)
key_left = current_key_bin[:28]
key_right = current_key_bin[28:]
for i in range(0, r):
key_left = move(key_left, -left_rotations[i])
key_right = move(key_right, -left_rotations[i])
key = translation(key_left + key_right, pc2)
secret_key.append(key)
def wheel_structure(left, right, current_round, types):
if types == 1:
key = secret_key[current_round]
else:
key = secret_key[-(current_round+1)]
temp2 = right
right = xor(left, func_f(right, key))
left = temp2
return left, right
def encode(plain_texts, rounds, key, types):
generate_secret(key, rounds)
plain_texts = change_hex_to_bin(plain_texts)
plain_texts = translation(plain_texts, ip)
cipher_text = ''
left = plain_texts[:32]
right = plain_texts[32:]
for i in range(0, rounds):
left, right = wheel_structure(left, right, i, types)
cipher_text += right + left
cipher_text = translation(cipher_text, ip_)
cipher_text = hex(int(cipher_text, 2))[2:].upper().rjust(16, '0')
return cipher_text
def main(texts, s_key, s_rounds, ty):
c_texts = ''
if ty == 1:
print('要加密的明文为：', texts)
for i in range(0, len(texts), 16):
c_texts += encode(texts[i:i+16].ljust(16, '0').upper(), int(s_rounds), s_key, ty)
print('密文：', c_texts)
else:
print('要解密的密文为：', texts)
for i in range(0, len(texts), 16):
c_texts += encode(texts[i:i+16].ljust(16, '0').upper(), int(s_rounds), s_key, ty)
print('明文：', c_texts)
return c_texts
if __name__ == '__main__':
secret_key = []
path = ''
types1 = int(input('加密or解密(加密:1,解密:2)'))
types2 = int(input('字符串or文件(字符串:1,文件:2)'))
if types2 == 1:
if types1 == 1:
plain_text = input('请输入要加密的明文(16的倍数个十六进制数字符串):')
else:
plain_text = input('请输入要解密的密文(16的倍数个十六进制数字符串):')
else:
path = input('请输入文件的路径(文件内容必须为16的倍数个十六进制数字符串):')
with open(path, 'r') as pl:
plain_text = pl.read()
if types1 == 1:
keys = input('请输入加密密钥(16个十六进制数字符串):')
else:
keys = input('请输入解密密钥(16个十六进制数字符串):')
round_s = 16
text = main(plain_text, keys, round_s, types1)
if types2 != 1:
with open(path, 'w') as pl:
pl.write(text)
在table.py里存取几个需要用到的表
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_ = [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]
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, 23, 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]
table_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]
table_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]
left_rotations = [
1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
]
s_box = [
# 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],
# 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],
# 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],
# 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],
# 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],
# 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],
# 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],
# 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],
]