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A comment on Google CTF 2019. Parent comment

Re:Google CTF 2019 by archgoon on Monday June 24, 2019 @04:28AM (#20261503)
How did you implement the JUMP_TOP instruction? You need to jump to the x86_64 instructions that correspond to the given emoji index; did you implement a jump table?
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Re:Google CTF 2019 by tntn on Monday June 24, 2019 @12:06PM (#20264971)
Yeah, I put labels corresponding to the original IP throughout and used a jump table.
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Re:Google CTF 2019 by archgoon on Monday June 24, 2019 @03:00PM (#20267147)
That's pretty cool! I just transliterated the instructions into C macros; but i didn't bother with the jump tables. The nice thing with this approach is that you can mix vm instructions with c code freely; and get gdb support. I needed that because speeding up via C wasnt enough to decode the full URL and I still needed to do additional reversing.

Was your method fast enough to get all three parts of the URL?

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Re:Google CTF 2019 by tntn on Monday June 24, 2019 @03:15PM (#20267326)
It produces the full domain name (up to .com) in ~ 1 minute. If there is more to the url (a path, ?= parameters, etc) after the domain name, then no.
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