Example #1
0
 def check(self,s):
   txt = c16.cbcdecrypt(s,self.iv,self.key)
   for c in txt:
     if ord(c) > 126 or ord(c) < 32:
       raise Exception(txt)
   return True
Example #2
0
 def check(self, s):
     txt = c16.cbcdecrypt(s, self.iv, self.key)  #这个是cbc模式的解密函数
     for c in txt:
         if ord(c) > 126 or ord(c) < 32:
             raise Exception(txt)
     return True
Example #3
0
  def myinput(self,s):
    s = s.replace(";","\;").replace("=","\=")

    return c16.cbcencrypt(self.prefix+s+self.suffix,self.iv,self.key)

  def check(self,s):
    txt = c16.cbcdecrypt(s,self.iv,self.key)
    for c in txt:
      if ord(c) > 126 or ord(c) < 32:
        raise Exception(txt)
    return True

if __name__ == "__main__":

  t = c27()
  enc = list(t.myinput(""))
  test = "".join(enc[:16]+["\x00"]*16+enc[:16]+enc[16:])

  dec = ""
  try:
    out = t.check(test)
    print "no exception, try one more time"
    sys.exit(1)
  except Exception, e:
    dec = str(e)

  key = [chr(ord(c1)^ord(c2)) for c1,c2 in zip(dec[:16],dec[32:48])]

  txt = c16.cbcdecrypt("".join(enc),"".join(key),"".join(key))
  print txt.encode('string_escape')
Example #4
0
        txt = c16.cbcdecrypt(s, self.iv, self.key)  #这个是cbc模式的解密函数
        for c in txt:
            if ord(c) > 126 or ord(c) < 32:
                raise Exception(txt)
        return True
        #这个函数是检测每个字节是否在ascii允许的范围内(32-126)


if __name__ == "__main__":

    t = c27()
    enc = list(t.myinput("hahahah"))  #加密信息并且用list形式保存
    print 'enc is :' + "".join(enc) + '\n'  #这是加密之后的信息
    test = "".join(enc[:16] + ["\x00"] * 16 + enc[:16] +
                   enc[16:])  #这个地方把加密之后的信息故意填充把密文信息改变之后作为测试
    print 'change enc is :' + test + '\n'  #这个是把密文篡改之后的信息
    dec = ""
    try:
        out = t.check(test)  #这个函数是检测每个字节是否在ascii允许的范围内(32-126)
        print "no exception, try one more time"
        sys.exit(1)
    except Exception, e:
        dec = str(e)
        print 'error msg:' + dec + '\n'  #这里是报错信息,报错信息会泄露key

    key = [chr(ord(c1) ^ ord(c2))
           for c1, c2 in zip(dec[:16], dec[32:48])]  #通过泄露信息还原出key
    print 'recover key :' + "".join(key) + '\n'
    txt = c16.cbcdecrypt("".join(enc), "".join(key), "".join(key))  #解密
    print txt.encode('string_escape')  #还原出消息