DES演算法 Python版本實現
阿新 • • 發佈:2019-01-07
#統一按照字串處理,輸入字串輸出也是字串。
def IP(Mingwen):
assert len(Mingwen)==64
IPtable=[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]
ret=""
for i in IPtable:
ret=ret+Mingwen[i-1 ]
return ret
#迴圈左移位數
def shift(a,s):
try:
if len(a)>28:
raise NameError
except TypeError:
pass
a=a[s:]+a[0:s]
return a
def createSubkey(key):
assert len(key)==64
Clist=[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]
Dlist=[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]
#初試生成
C0=""
D0=""
for i in Clist:
C0+=key[i-1]
for i in Dlist:
D0+=key[i-1]
assert len(C0)==28
assert len(D0)==28
Movetimes=[1,1,2,2,2,2,2,2,1,2,2,2,2,2 ,2,1]
retkey=[]
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]
for i in range(0,16):
C0=shift(C0,Movetimes[i])
D0=shift(D0,Movetimes[i])
temp=C0+D0
tempkey=""
for i in PC_2:
tempkey+=temp[i-1]
assert len(tempkey)==48
retkey.append(tempkey)
tempkey=""
return retkey
def Etuozhan(Rn):
Elist=[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]
retRn=""
for i in Elist:
retRn+=Rn[i-1]
assert len(retRn)==48
return retRn
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)]
Phezhihuan=[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 S_sub(Ln,Rn,subkey,oldRn):
tempresult=int(Rn,base=2)^int(subkey,base=2)
tempresult=bin(tempresult)[2:]
while len(tempresult)<48:
tempresult="0"+tempresult
index=0
retstr=""
for list in S:
hang=int(tempresult[index]+tempresult[index+5],base=2)
lie=int(tempresult[index+1:index+5],base=2)
a=bin(list[hang*16+lie])[2:]
while len(a)<4:
a="0"+a
retstr+=a
index+=6
assert len(retstr)==32
tmp=""
for i in Phezhihuan:
tmp+=retstr[i-1]
a=int(tmp, base=2) ^ int(Ln, base=2)
a=bin(a)[2:]
while len(a)<32:
a="0"+a
assert len(a)==32
(Ln,Rn)=(oldRn,a)
w5555555555=Ln+Rn
return (Ln,Rn)
def P_1(L16,R16):
tmp=L16+R16
list=[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]
retstr=""
for i in list:
retstr+=tmp[i-1]
assert len(retstr)==64
return retstr
if __name__=="__main__":
key="0001001000110100010101100111100010010001001000110100010101100111"
Mingwen= "1001100001110110010101000011001000010001010001110010010110000011"
Chushizhihuan=IP(Mingwen)
subkeylist=createSubkey(key)
Ln=Chushizhihuan[0:32]
Rn=Chushizhihuan[32:]
for subkey in subkeylist:
while len(Rn)<32:
Rn="0"+Rn
while len(Ln)<32:
Ln="0"+Ln
Rn_tuozhan=Etuozhan(Rn)
(Ln,Rn)=S_sub(Ln,Rn_tuozhan,subkey,Rn)
# print(hex(int(Ln+Rn,base=2))[2:].upper())
(Ln,Rn)=(Rn,Ln)
b=P_1(Ln,Rn)
print(hex(int(b,base=2)).upper())