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计算机安全DES算法实现
# coding=utf-8
"""
计算机安全DES算法实现
"""
# @Time: 2018/12/9 1:55
# @File: des.py
base = [str(x) for x in range(10)] + [chr(x) for x in range(ord('A'), ord('A') + 6)]
# bin2dec
# 二进制 to 十进制: int(str,n=10)
def bin2dec(string_num):
return str(int(string_num, 2))
# hex2dec
# 十六进制 to 十进制
def hex2dec(string_num):
return str(int(string_num.upper(), 16))
# dec2bin
# 十进制 to 二进制: bin()
def dec2bin(string_num):
num = int(string_num)
mid = []
while True:
if num == 0: break
num, rem = divmod(num, 2)
mid.append(base[rem])
return ''.join([str(x) for x in mid[::-1]])
# dec2hex
# 十进制 to 八进制: oct()
# 十进制 to 十六进制: hex()
def dec2hex(string_num):
num = int(string_num)
if num == 0:
return '0'
mid = []
while True:
if num == 0: break
num, rem = divmod(num, 16)
mid.append(base[rem])
return ''.join([str(x) for x in mid[::-1]])
# hex2tobin
# 十六进制 to 二进制: bin(int(str,16))
def hex2bin(string_num):
return dec2bin(hex2dec(string_num.upper()))
# bin2hex
# 二进制 to 十六进制: hex(int(str,2))
def bin2hex(string_num):
return dec2hex(bin2dec(string_num))
def intArr2ASC(arr):
return binary2ASC(intArr2Str(arr))
'''
/**
* PBOC3DES 加密算法
* @author Administrator
*
*/
'''
class PBOC_DES():
pass
'''
/** ***************************压缩替换S-Box************************************************* */
'''
subKey = [([0] * 48) for ll in range(16)]
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]]
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]
# 每次密钥循环左移位数
LS = [1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1]
'''
/**
* IP初始置换
* @param source
* @return
*/
'''
def changeIP(source):
dest = [0] * 64
global ip
for i in range(64):
dest[i] = source[ip[i] - 1]
return dest
def string2Binary(str):
le = len(str)
dest = [0] * le * 4
i = 0
for c in str:
i += 4
j = 0
s = hex2bin(c)
l = len(s)
for d in s:
dest[i - l + j] = int(d)
j += 1
return dest
'''
/**
* IP-1逆置
* @param source
* @return
*/
'''
def changeInverseIP(source):
dest = [0] * 64
global _ip
for i in range(64):
dest[i] = source[_ip[i] - 1]
return dest
'''
/**
*
* 获取轮子密钥(48bit)
*
* @param source
*
* @return
*
*/
'''
def setKey(source):
global subKey
# 装换4bit
print(u"(a)推导K_1")
temp = string2Binary(source)
# 6bit均分成两部分
left = [0] * 28
right = [0] * 28
# 经过PC-14bit转换6bit
temp1 = [0] * 56
temp1 = keyPC_1(temp)
print(u"PC1操作后 : {}".format(intArr2ASC(temp1)))
# printArr(temp1);
# 将经过转换的temp1均分成两部分
for i in range(28):
left[i] = temp1[i]
right[i] = temp1[i + 28]
# 经过16次循环左移,然后PC-2置换
pass # 分成两部分
print("C_1-1 : {v}".format(v=intArr2ASC(left)))
print("D_1-1 : {v}".format(v=intArr2ASC(right)))
for i in range(16):
left = keyLeftMove(left, LS[i])
right = keyLeftMove(right, LS[i])
pass # 左移后
if i==0:
print(u"经过第{i}次左移".format(i=i+1))
print("C_{i} : {v}".format(i=i+1,v=intArr2ASC(left)))
print("D_{i} : {v}".format(i=i+1,v=intArr2ASC(right)))
for j in range(28):
temp1[j] = left[j]
temp1[j + 28] = right[j]
subKey[i] = keyPC_2(temp1)
if i==0:
print("K_{i}:{v}".format(i=i+1, v=intArr2ASC(subKey[i])))
# print("其他密钥:")
# print("subKey[{i}]:{v}".format(i=i, v=intArr2ASC(subKey[i])))
# print(u"密钥经过16次循环左移PC-2置换")
# for i,v in enumerate(subKey):
# print("subKey[{i}]:{v}".format(i=i,v=intArr2ASC(v)))
pass
'''
/**
*
* 6bit的密钥转换成48bit
* @param source
* @return
*
*/
'''
def keyPC_2(source):
dest = [0] * 48
temp = [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]
for i in range(48):
dest[i] = source[temp[i] - 1]
return dest
'''
/**
*
* 将密钥循环左移i
* @param source 二进制密钥数
* @param i 循环左移位数
* @return
*
*/
'''
def keyLeftMove(source, i):
temp = 0
global LS
le = len(source)
ls = LS[i]
for k in range(ls):
temp = source[0]
for j in range(le - 1):
source[j] = source[j + 1]
source[le - 1] = temp
return source
'''
/**
*
* 4bit的密钥转换成56bit
* @param source
* @return
*
*/
'''
def keyPC_1(source):
dest = [0] * 56
temp = [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]
for i in range(56):
dest[i] = source[temp[i] - 1]
return dest
'''
/**
* 两个等长的数组做异或
* @param source1
* @param source2
* @return
*/
'''
def diffOr(source1, source2):
le = len(source1)
dest = [0] * le
for i in range(le):
dest[i] = source1[i] ^ source2[i]
return dest
'''
/**
*
* DES加密--->对称密钥
* D = Ln(32bit)+Rn(32bit)
* 经过16轮置
* @param D(16byte)明文
* @param K(16byte)轮子密钥
* @return (16byte)密文
*/
'''
def encryption(D, K):
setKey(K) # sub key ok
temp = [0] * 64
data = string2Binary(D)
# 第一步初始置
data = changeIP(data)
left = [([0] * 32) for i in range(17)]
right = [([0] * 32) for i in range(17)]
for j in range(32):
left[0][j] = data[j]
right[0][j] = data[j + 32]
print("(b)初始置换后")
print("L0: {}".format(intArr2ASC(left[0])))
print("R0: {}".format(intArr2ASC(right[0])))
for i in range(1, 17):
# 获取(48bit)的轮子密
key = subKey[i - 1]
print(u"**进行第{i}次加密,Key={v}".format(i=i, v=intArr2ASC(key)))
# L1 = R0
left[i] = right[i - 1]
# R1 = L0 ^ f(R0,K1)
fTemp = f(right[i - 1], key) # 32bit
right[i] = diffOr(left[i - 1], fTemp)
print(u"计算R{i}=P(B) XOR L0 -> {v}".format(i=i, v=intArr2ASC(right[i])))
# 组合的时候,左右调换
for i in range(32):
temp[i] = right[16][i]
temp[32 + i] = left[16][i]
temp = changeInverseIP(temp)
str = binary2ASC(intArr2Str(temp))
print(u"最终密文:{}".format(str))
return str
'''
/**
* 8bit压缩2bit
* @param source(48bit)
* @return R(32bit) B=E(R)⊕K,将48 位的B 分成8 个分组,B=B1B2B3B4B5B6B7B8
*/
'''
def press(source):
ret = [0] * 32
temp = [([0] * 6) for i in range(8)]
s = [s1, s2, s3, s4, s5, s6, s7, s8]
st = []
for i in range(8):
for j in range(6):
temp[i][j] = source[i * 6 + j]
# print(u"(e) 组合{i} : {v}".format(i=i,v=temp[i]))
for i in range(8):
# (16)
x = temp[i][0] * 2 + temp[i][5]
# (2345)
y = temp[i][1] * 8 + temp[i][2] * 4 + temp[i][3] * 2 + temp[i][4]
val = s[i][x][y]
ch = dec2hex(str(val))
# System.out.println("x=" + x + ",y=" + y + "-->" + ch);
# String ch = Integer.toBinaryString(val);
st.append(ch)
# print(u"(e)S替代后{i} : {v}".format(i=i,v=st[i]))
# System.out.println(str.toString());
print("(e) S盒替换")
for i in range(8):
s="".join([str(each) for each in temp[i]])
d="".join([str(each) for each in string2Binary(st[i])])
print(u"第{i}组:{s} -> {d}".format(i=i,s=s,d=d))
ret = string2Binary(st)
# printArr(ret);
# 置换P
print("(f)连接成32位整数B")
print("B : {v}".format(v=intArr2ASC(ret)))
ret = dataP(ret)
print("(g)P(B) : {v}".format(v=intArr2ASC(ret)))
return ret
'''
/**
* 置换P(32bit)
* @param source
* @return
*/
'''
def dataP(source):
dest = [0] * 32
temp = [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]
le = len(source)
for i in range(le):
dest[i] = source[temp[i] - 1]
return dest
'''
/**
* 2bit扩展8bit
* @param source
* @return
*/
'''
def expend(source):
ret = [0] * 48
temp = [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]
for i in range(48):
ret[i] = source[temp[i] - 1]
return ret
'''
/**
* @param R(2bit)
* @param K(48bit的轮子密
* @return 32bit
*/
'''
def f(R, K):
dest = [0] * 32
temp = [0] * 48
# 先将输入32bit扩展8bit
expendR = expend(R) # 48bit
print(u"(c) 扩展后:{v}".format(v=intArr2ASC(expendR)))
# 与轮子密钥进行异或运
temp = diffOr(expendR, K)
print(u"(d) 异或运算后{v}".format(v=intArr2ASC(temp)))
# 压缩2bit
dest = press(temp)
# print(u"(f) 压缩".format(v=intArr2ASC(dest)) )
return dest
'''
/**
* 将int类型数组拼接成字符串
* @param arr
* @return
*/
'''
def intArr2Str(arr):
sb = []
le = len(arr)
for i in range(le):
sb.append(str(arr[i]))
return ''.join(sb)
'''
/**
* 将二进制字符串转换成十六进制字符
* @param s
* @return
*/
'''
def binary2ASC(s):
st = ''
ii = 0
le = len(s)
# 不够4bit左补0
if le % 4 != 0:
while ii < (4 - len % 4):
s = "0" + s
le = le / 4
for i in range(le):
st += bin2hex(s[i * 4: i * 4 + 4])
return st
if __name__ == "__main__":
D = '0123456789ABCDEF'
K = '0123456789ABCDEF'
print encryption(D, K)
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