Decompetition

Calling all reverse engineers! Test your reversing skills against the systems languages of the twenty-first century: C, C++, Go, Rust, and Swift. Given only a binary, can you recreate the original source code?

Your candidate source code will be compiled, and the resulting binary will be tested and disassembled. The majority of your score will come from the intersection over union of your disassembly versus the target disassembly. How close can you get to a perfect reconstruction?

The Details

Playing

Anyone with an internet connection and a web browser can play. Access to a reverse engineering program is recommended but not required. If you don't have any reversing software installed, check out Binary Ninja Cloud.

This is a team competition. There's no team size limit.

Scoring

Your candidate source code will be compiled, and the resulting binary will be tested and disassembled. Your score on any challenge is made up of:

• 20% unit tests. Pass (hidden) test cases to get these points.
• 60% binary diff. Match the target disassembly to get these points.
• 20% perfect match. Bonus points for a perfect binary match.

The test case points and the binary diff points can be partial—you'll get more and more points as you improve your source code—but the final 20% bonus for a perfect match is all-or-nothing.

Prizes

The top three teams will win themselves some Amazon gift cards. In the case of a tie, the team that achieved the high score first wins. All prizes are in USD:

• $500 for first place.
• $300 for second place.
• $200 for third place.

Additionally, Vector 35 is donating Binary Ninja licenses—personal edition, one license per team—for the first and second place teams!

Environment

All challenges were built for x86-64 and run on Ubuntu 20.04. Compilers are:

• gcc 9.3.0
• g++ 9.3.0 -std=c++17
• go 1.13.8
• rustc 1.43.0
• swiftc 5.2.4

Disclaimer

Decompetition is part of a research project on the process of reverse engineering. Our research is mainly exploratory:

• We're interested in following the full reversing process, to see how reversers work as they go from nothing to fully equivalent source code.
• We're interested to see how a fast compile-disassemble-diff feedback loop affects the ease and confidence of reversing.

We'll record your source code submissions so we can follow the reversing process. So don't upload any private information in your source. Not that you were going to do that, right?