'전체 글'에 해당되는 글 22건

reference : https://www.hauri.co.kr/security/security_view.html?intSeq=15&page=1&keyfield=&key=

#-*-coding:utf-8 -*-

import base64

def Operator(key):
    result = []
    OPkey = [0x28, 0x4, 0x20, 0x20]
    idx = 0
   
    for a in key:
        result.append(a + OPkey[idx])
        idx += 1

    return result

   
with open('str_info.txt', mode='rt') as f:
    result = f.read()
    result_list = result.split()
   
    for b64_encStr in result_list:
        b64_decStr = base64.b64decode(b64_encStr)
        data = b64_decStr[4:]
        key = b64_decStr[:4]
      
        result = ""

        if len(data)%4:
            for padding in range(4-len(data)%4):
                data += b"0"

        for dataSplit in zip(*[list(data[z::4]) for z in range(4)]):
            overflow = 0
            for index in range(4):
                if overflow:
                    key[index] = int(key[index])+int(overflow)
                    overflow = 0
                
                if key[index] > 255:
                    overflow  = int(str(hex(key[index]))[-3])
                    key[index] = int(str(hex(key[index]))[-2:], 16)
                    key[index] = int(key[index])
                    
                result += chr(dataSplit[index]^key[index])
            key = Operator(key)
            
        print(result)