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求关注公众号 lin先森

传统知识+古典密码 |?古典密码 栅栏 凯撒

https://www.jianshu.com/p/57c121948d74

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28 30 23 8 17 10 16 30
88 90 83 68 77 70 76 90
XZSDMFLZ
栅栏
XMZFSLDZ
凯撒
SHUANGYU

Rabbit | ?rabbit解码

https://www.sojson.com/encrypt_rabbit.html
在线解码

rsa | ?easy

import gmpy2
p=473398607161
q=4511491
e=17
d = gmpy2.invert(e,(q-1)*(p-1))
print d

Alice与Bob | ?分解n

$a='98554799767';
$a=floatval($a);

for((float)$i=2;$i<(float)$a;$i++){
        $num=fmod($a,$i);
        if($num==0){
                echo $i."\n";
                break;
        }
}
$j=$a/$i;
echo $j."\n";
echo md5($i.$j);
?>

篱笆墙的影子 | ?栅栏密码

栅栏密码

权限获得第一步

给的文件：Administrator:500:806EDC27AA52E314AAD3B435B51404EE:F4AD50F57683D4260DFD48AA351A17A8:::

这好像是Linux的shadow文件，密码是F4AD50F57683D4260DFD48AA351A17A8

用https://www.cmd5.com

rsa2 | easy

RSAROLL

import gmpy2
n = 920139713
q = 18443
p = 49891
e = 19
d = int(gmpy2.invert(e , (p-1) * (q-1)))  

c = '''704796792
752211152
274704164
18414022
368270835
483295235
263072905
459788476
483295235
459788476
663551792
475206804
459788476
428313374
475206804
459788476
425392137
704796792
458265677
341524652
483295235
534149509
425392137
428313374
425392137
341524652
458265677
263072905
483295235
828509797
341524652
425392137
475206804
428313374
483295235
475206804
459788476
306220148'''
falg = ''
for ii in c.split('\n'):
	falg += chr(pow(int(ii),d,n))
print falg

Dangerous RSA

import gmpy2
import libnum
c=
gmpy2.iroot(c,3)
libnum.n2s()

import binascii
import libnum
a = hex(13040004482819713819817340524563023159919305047824600478799740488797710355579494486728991357)
aa = a[2:-1]
print binascii.unhexlify(aa)

Windows系统密码

md5解码

RSA1 | easy

还原大师 | easy

爆破

异性相吸 | xor

#-*-coding:utf-8 -*-
with open('密文.txt'.decode('utf-8'),'rb') as a:
    a=a.read()
with open('key.txt','rb') as b:
    b=b.read()
d=''
print len(b)
print len(a)
for i in range(0,len(b)):
    c=chr(ord(a[i])^ord(b[i]))
    d+=c
print(d)

凯撒？替换？呵呵!

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