import base64,re,sys
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]
IP_re_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]
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],
]
#key
PC_1 = [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]
PC_2 = [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]
#秘钥左移的位数
SHIFT = [1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1]
def write_in_file(str_mess):
try:
f = open(‘DES.txt’,’w’,encoding=’utf-8′)
f.write(str_mess)
f.close()
print(“文件输出成功！”)
except IOError:
print(‘文件加解密出错！！！’)
def read_out_file():
try:
f = open(‘DES.txt’,’r’,encoding = ‘utf-8’)
mess = f.read()
f.close()
print(“文件读取成功！”)
return mess
except IOError:
print(‘文件加解密出错！！！’)
#字符串转化为二进制
def str2bin(message):
res = “”
for i in message: #对每个字符进行二进制转化
tmp = bin(ord(i))[2:] #字符转成ascii，再转成二进制，并去掉前面的0b
for j in range(0,8-len(tmp)): #补齐8位
tmp = ‘0’+ tmp #把输出的b给去掉
res += tmp
return res
#二进制转化为字符串
def bin2str(bin_str):
res = “”
tmp = re.findall(r’.{8}’,bin_str) #每8位表示一个字符
for i in tmp:
res += chr(int(i,2)) #base参数的意思，将该字符串视作2进制转化为10进制
print(“未经过编码的加密结果:”+res)
print(“经过base64编码:”+str(base64.b64encode(res.encode(‘utf-8′)),’utf-8’))
return res
#IP盒处理
def ip_change(bin_str):
res = “”
for i in IP_table:
res += bin_str[i-1] #数组下标i-1
return res
#IP逆盒处理
def ip_re_change(bin_str):
res = “”
for i in IP_re_table:
res += bin_str[i-1]
return res
#E盒置换
def e_str(bin_str):
res = “”
for i in E:
res += bin_str[i-1]
return res
#字符串异或操作
def str_xor(my_str1,my_str2): #str，key
res = “”
for i in range(0,len(my_str1)):
xor_res = int(my_str1[i],10)^int(my_str2[i],10) #变成10进制是转化成字符串 2进制与10进制异或结果一样，都是1,0
if xor_res == 1:
res += ‘1’
if xor_res == 0:
res += ‘0’
return res
#循环左移操作
def left_turn(my_str,num):
left_res = my_str[num:len(my_str)]
#left_res = my_str[0:num]+left_res
left_res = left_res+my_str[0:num]
return left_res
#秘钥的PC-1置换
def change_key1(my_key):
res = “”
for i in PC_1: #PC_1盒上的元素表示位置 只循环64次
res += my_key[i-1] #将密钥按照PC_1的位置顺序排列，
return res
#秘钥的PC-2置换
def change_key2(my_key):
res = “”
for i in PC_2:
res += my_key[i-1]
return res
# S盒过程
def s_box(my_str):
res = “”
c = 0
for i in range(0,len(my_str),6):#步长为6 表示分6为一组
now_str = my_str[i:i+6] #第i个分组
row = int(now_str[0]+now_str[5],2) #b1b6 =r 第r行
col = int(now_str[1:5],2) #第c列
#第几个s盒的第row*16+col个位置的元素
num = bin(S[c][row*16 + col])[2:] #利用了bin输出有可能不是4位str类型的值，所以才有下面的循环并且加上字符0
for gz in range(0,4-len(num)):
num = ‘0’+ num
res += num
c += 1
return res
#P盒置换
def p_box(bin_str):
res = “”
for i in P:
res += bin_str[i-1]
return res
# F函数的实现
def fun_f(bin_str,key):
first_output = e_str(bin_str) #位选择函数将32位待加密str拓展位48位
second_output = str_xor(first_output,key) #将48位结果与子密钥Ki按位模2加 得到的结果分为8组（6*8）
third_output = s_box(second_output) #每组6位缩减位4位 S盒置换
last_output = p_box(third_output) #P盒换位处理 得到f函数的最终值
return last_output
def gen_key(key):
key_list = []
divide_output = change_key1(key)
key_C0 = divide_output[0:28]
key_D0 = divide_output[28:]
for i in SHIFT: #shift左移位数
key_c = left_turn(key_C0,i)
key_d = left_turn(key_D0,i)
key_output = change_key2(key_c + key_d)
key_list.append(key_output)
return key_list
def des_encrypt_one(bin_message,bin_key): #64位二进制加密的测试
#bin_message = deal_mess(str2bin(message))
mes_ip_bin = ip_change(bin_message) #ip转换
#bin_key = input_key_judge(str2bin(key))
key_lst = gen_key(bin_key) #生成子密钥
mes_left = mes_ip_bin[0:32]
mes_right = mes_ip_bin[32:]
for i in range(0,15):
mes_tmp = mes_right #暂存右边32位
f_result = fun_f(mes_tmp,key_lst[i]) #右32位与k的f函数值
mes_right = str_xor(f_result,mes_left) #f函数的结果与左边32位异或 作为下次右边32位
mes_left = mes_tmp #上一次的右边直接放到左边
f_result = fun_f(mes_right,key_lst[15]) #第16次不用换位，故不用暂存右边
mes_fin_left = str_xor(mes_left,f_result)
mes_fin_right = mes_right
fin_message = ip_re_change(mes_fin_left + mes_fin_right) #ip的逆
return fin_message #返回单字符的加密结果
##64位二进制解密的测试,注意秘钥反过来了，不要写错了
def des_decrypt_one(bin_mess,bin_key):
mes_ip_bin = ip_change(bin_mess)
#bin_key = input_key_judge(str2bin(key))
key_lst = gen_key(bin_key)
lst = range(1,16) #循环15次
cipher_left = mes_ip_bin[0:32]
cipher_right = mes_ip_bin[32:]
for i in lst[::-1]: #表示逆转列表调用
mes_tmp = cipher_right
cipher_right = str_xor(cipher_left,fun_f(cipher_right,key_lst[i]))
cipher_left = mes_tmp
fin_left = str_xor(cipher_left,fun_f(cipher_right,key_lst[0]))
fin_right = cipher_right
fin_output = fin_left + fin_right
bin_plain = ip_re_change(fin_output)
res = bin2str(bin_plain)
return res
#简单判断以及处理信息分组
def deal_mess(bin_mess):
“””
:param bin_mess: 二进制的信息流
:return: 补充的64位信息流
“””
ans = len(bin_mess)
if ans % 64 != 0:
for i in range( 64 – (ans%64)): #不够64位补充0
bin_mess += ‘0’
return bin_mess
#查看秘钥是否为64位
def input_key_judge(bin_key):
“””
全部秘钥以补0的方式实现长度不满足64位的
:param bin_key:
“””
ans = len(bin_key)
if len(bin_key) ‘)
if mode == ‘1’:
print(“请输入信息输入字符串不能为空：”)
message = input().replace(‘ ‘,”)
print(“请输入你的秘钥：”)
key = input().replace(‘ ‘,”)
s = all_message_encrypt(message,key)
out_mess = bin2str(s)
print(“加密过后的内容:”+ out_mess)
write_in_file(out_mess)
#print(type(out_mess))
# base_out_mess = base64.b64encode(out_mess.encode(‘utf-8’))
# print(“Base64编码过后:”+ base_out_mess.decode())
elif mode == ‘2’:
# print(“请输入信息输入字符串不能为空：”)
# message = input().replace(‘ ‘, ”)
print(“请输入你的秘钥：”)
key = input().replace(‘ ‘, ”)
message = read_out_file()
s = all_message_decrypt(message, key)
#out_mess = bin2str(s)
print(“解密后的信息：”+ s)
else:
print(“请重新输入！”)
if __name__ == ‘__main__’:
print(sys.getdefaultencoding())
while True:
get_mode()路虽远行则将至，事虽难做则必成！
