Kind of stuck on babyrev15

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Martin Petkov

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Jun 7, 2021, 7:24:24 PM6/7/21
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I'm kind of stuck on babyrev15 and would like a little help.

The way I approached babyrev15_teaching is by "dynamically" reverse-engineering it. I placed a breakpoint at interpret_cmp and deduced the correct bytes based on what was being compared.

However, for babyrev15_testing, that only worked up to some number of bytes, after which my input in no way affected what was being compared. It seems like it's always the same values, but my key input doesn't affect them in any way.

I'm planning to spend more time reversing the decompiled code and reaching enlightenment, but I also wanted to ask for a hint or some idea why my approach only worked partially.

Martin Petkov

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Jun 7, 2021, 7:40:16 PM6/7/21
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Actually I just realized I had a bug. I automated part of the process and did some of the math kind of wrong. I'm back on track!
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