南京郵電大學CTF-密碼學-mixed_base64
阿新 • • 發佈:2019-01-30
題目如下:
1.先把code.txt儲存為一個檔案
2.加密過程:
十次加密,每一次在base16,32,64中隨機選擇一種加密
3.解密過程:
用python直接嘗試爆破
解密程式碼:
#*****題目:多重base64加密 #*****python破解程式碼 import base64 def decode_mix_base64(b): a = b # print a i = 0 while True: i = i+1 print i #base16 try: c = base64.b16decode(a) a = c print('using base16 decode sucess.....') continue except: print ('using base16 decode failuer.....') pass #base32 try: c = base64.b32decode(a) a = c print('using base32 decode sucess.....') continue except: print ('using base32 decode failuer.....') pass #base64 try: c = base64.b64decode(a) a = c print('using base64 decode sucess.....') continue except: print ('using base64 decode failuer.....') pass break print a def main(): a = open('ctf_code_base64.txt') try: b = a.read() finally: a.close() #while True: try: #b = base64.b64decode(b) decode_mix_base64(b) except: print ('Finish!*********') #break if __name__ == '__main__': main()
執行程式破解flag
ok,完成,拿到flag