Bugku-CTF加密篇之進制轉換（二進制、八進制、十進制、十六進制，你能分的清嗎？）

進制轉換

 

二進制、八進制、十進制、十六進制，你能分的清嗎？

 

 

本題要點：進制轉換、常用進制類型

 

 

內容如下：

 

d87 x65 x6c x63 o157 d109 o145 b100000 d116 b1101111 o40 x6b b1100101 b1101100 o141 d105 x62 d101 b1101001 d46 o40 d71 x69 d118 x65 x20 b1111001 o157 b1110101 d32 o141 d32 d102 o154 x61 x67 b100000 o141 d115 b100000 b1100001 d32 x67 o151 x66 d116 b101110 b100000 d32 d102 d108 d97 o147 d123 x31 b1100101 b110100 d98 d102 b111000 d49 b1100001 d54 b110011 x39 o64 o144 o145 d53 x61 b1100010 b1100011 o60 d48 o65 b1100001 x63 b110110 d101 o63 b111001 d97 d51 o70 d55 b1100010 d125 x20 b101110 x20 b1001000 d97 d118 o145 x20 d97 o40 d103 d111 d111 x64 d32 o164 b1101001 x6d o145 x7e

 

 

 

 

從這一串進制編碼來看，分別有  d、x、o、b 。

 

八進制（逢八進一），Octal，縮寫OCT或O，一種以8為基數的計數法，用O表示，為了不與數字0混淆，有時也用Q來表示八進制數。

十進制（逢十進一），英文為Decimal System，縮寫Dec或D，來源於希臘文Decem，用D表示。

十六進制（逢十六進一），英文名稱：Hexadecimal，是計算機中數據的一種表示方法。它由0-9，A-F組成，字母不區分大小寫，前綴用0x表示。

二進制（逢二進一），Binary，用b表示。

 

所以簡單的來說：

D：十進制數Decima

B：二進制數Binary

0x（H）：十六進制數Hexadecimal

O：八進制數Octal 

 

因此，我們將這些統一轉化為十六進制表示，然后轉為字符串就可以得到答案啦~

 

貼上大佬的進制轉換代碼腳本~

 

注：需要python2的環境哈~

       python3.8會報錯~

#! /usr/bin/env python
#coding=utf-8
s=["d87","x65","x6c","x63","o157","d109","o145","b100000","d116","b1101111","o40","x6b","b1100101","b1101100","o141","d105","x62","d101","b1101001","d46","o40","d71","x69","d118","x65","x20","b1111001","o157","b1110101","d32","o141","d32","d102","o154","x61","x67","b100000","o141","d115","b100000","b1100001","d32","x67","o151","x66","d116","b101110","b100000","d32","d102","d108","d97","o147","d123","x31","b1100101","b110100","d98","d102","b111000","d49","b1100001","d54","b110011","x39","o64","o144","o145","d53","x61","b1100010","b1100011","o60","d48","o65","b1100001","x63","b110110","d101","o63","b111001","d97","d51","o70","d55","b1100010","d125","x20","b101110","x20","b1001000","d97","d118","o145","x20","d97","o40","d103","d111","d111","x64","d32","o164","b1101001","x6d","o145","x7e"]
s1=""
t=""
t1=""
for i in s:
    s1=i
    for j in range(1):
        if s1[0:1]=='d':
            t=str(hex(int(s1[1:])))
            t=t[2:]+" "
            t1=t1+t
        if s1[0:1]=='x':
            t=s1[1:]+" "
            t1=t1+t
        if s1[0:1]=='o':
            t=str(hex(int(s1[1:],8)))
            t=t[2:]+" "
            t1=t1+t            
        if s1[0:1]=='b':
            t=str(hex(int(s1[1:],2)))
            t=t[2:]+" "
            t1=t1+t
print t1     
 

 

這里用到的是菜鳥工具的python2在線運行網站：

  https://c.runoob.com/compile/6 

 

 

 

我們將這一串十六進制數轉換成字符串的形式~

 

16進制到文本字符串轉換在線網站：

  https://www.bejson.com/convert/ox2str/ 

 

 

 

  Welcome to kelaibei. Give you a flag as a gift. flag{1e4bf81a6394de5abc005ac6e39a387b} . Have a good time~ 

 

 

得到答案啦~

 

  flag{1e4bf81a6394de5abc005ac6e39a387b} 

 

bingo~

 

 

 

 

 

參考資料：

https://blog.csdn.net/An_Mei_Ying/article/details/89683709

https://baike.baidu.com/item/進制轉換/3117222?fr=aladdin