We Chall-Training: Encodings I -Writeup

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We Chall-Training: Encodings I -Writeup

題目連接:http://www.wechall.net/challenge/training/encodings1/index.php

原題以下：
We intercepted this message from one challenger to another, maybe you can find out what they were talking about.
To help you on your progress I coded a small java application, called JPK.
Note: The message is most likely in english.

10101001101000110100111100110100
00011101001100101111100011101000
10000011010011110011010000001101
11010110111000101101001111010001
00000110010111011101100011110111
11100100110010111001000100000110
00011110011110001111010011101001
01011100100000101100111011111110
10111100100100000111000011000011
11001111100111110111110111111100
10110010001000001101001111001101
00000110010111000011110011111100
11110011111010011000011110010111
0100110010111100100101110

• 從01，in English以及提供的JPK等提示推測以上數字的編碼方式爲二進制；
• 利用提供的JPK或者本身下載的JPK處理以上的01編碼：
  
• 將01編碼粘貼到Bianry->Bianry To Ascii中，經過Bianry->Bianry Format化爲8位一組：
  

• Bianry->Bianry To Ascii，將編碼轉爲ASCII碼，發現爲亂碼，查緣由發現8位一組時，多了一位0：

• 嘗試將01編碼化爲7個一組，恰好分完，
  

• Bianry->Bianry To Ascii，出現了正確的ASCII字符串：This text is 7-bit encoded ascii. Your password is easystarter.
  

則正確的flag即爲easystarter
2017-2-5 20:49;00