nthery/cxx-obfuscator

C/C++ code obfuscator

cxx-obfuscator is a filter that obfuscates a C/C++ source file or de-obfuscates a previously obfuscated file. The intended use case is reporting bugs to a compiler vendor without exposing confidential information.

cxx-obfuscator strikes a balance between protecting intellectual property and easing debugging of obfuscated code by not obfuscating standard identifiers by default.

The conceal subcommand obfuscates its standard input over its standard output. It maps identifiers (except whitelisted ones - see below) to words randomly selected from a pool. It removes comments. It leaves other tokens unchanged.

The whitelist contains identifiers that must not be obfuscated. It always contains C/C++ keywords (while, for...), identifiers starting with _ and some names with special meaning (begin(), end(), main()). The whitelist also contains by default all words in cxx-obfuscator.whitelist.txt if this file is found in the directory containing cxx-obfuscator. This default whitelist contains all identfiers found in /usr/include on a typical unix system. The -whitelist option specifies an alternative whitelist.

By default obfuscated identifiers are taken from a pool of words stored in cxx-obfuscator.pool.txt in the same directory as cxx-obfuscator. The -pool option specifies an alternative word pool.

The -map option specifies a file where the conceal subcommand writes the mapping between clear and obfuscated identifiers.

The reveal subcommand de-obfuscates its standard input over its standard output using the map file generated by the conceal subcommand.

The tokenize subcommand extracts tokens from its standard input. It is used both for generating pool and whitelist files.

To generate a whitelist file containing all tokens in files in /usr/include:

find /usr/include -type f -print | xargs cat | cxx-obfuscator tokenize > whitelist.txt

To generate a pool containing all words from Sherlock Holme's canon:

curl https://sherlock-holm.es/stories/plain-text/cano.txt | cxx-obfuscator tokenize > pool.txt