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DefCon CtF Quals 2014 writeup – hackertool
hey, we need to check that your connection works, torrent this file and md5 it
http://services.2014.shallweplayaga.me/hackertool.torrent_fe3b8b75e9639d35e8ac1d9809726ee2
The torrent file when loaded into Vuze showed that the file name was every_ip_address.txt. So I downloaded some of the file and observed the format. The format of the file was “0.0.0.1\n0.0.0.2\n…. “.
So I wrote a quick python script to calculate the md5:
#!/bin/python
import hashlib
m = hashlib.md5()
fsize = 0
a = ''
for i in xrange(256):
for j in xrange(256):
for k in xrange(256):
for l in xrange(256):
a = str(i)+'.'+str(j)+'.'+str(k)+'.'+str(l)+'\n'
fsize += len(a)
m.update( a )
print m.hexdigest()
The flag was “1a97f624cc74e4944350c04f5ae1fe8d”.