Bioruebe / brunsdec

A simple decryptor for Bruns Engine encrypted files

brunsdec

A simple decryptor for Bruns Engine encrypted files (with magic number EENC)

Usage

brunsdec <input_file>|<input_dir> [<output_dir>]

• brunsdec supports either a single file or a whole folder as input. In folder mode only files with magic number EENC are processed. Subdirectories are ++ignored++.

Technical details

Bruns Engine games make use of two different file formats:

• EENZ: Files starting with the magic number 45 45 4E 5A are generally used for text content (configuration, level data) and fonts. This kind of encryption is not supported by brunsdec.
• EENC: Encrpyted PNG images start with the magic number 45 45 4E 43 and can be decrypted by brunsdec. The next 4 bytes can be used to derive the encryption key, which is different for each file. To do so, XOR the value with 0xDEADBEEF to get the decryption key. (Attention: the byte order is important! See code for details.) Then simply XOR the rest of the file with the decryption key and save as PNG.

Limitations

• Files with the magic number EENZ are not supported
• If you found a game, which is not supported, feel free to open an issue and send me a sample file.

Remarks

This is the result of analysing the file type itself, no reverse engineering has been used to write this tool.

I released it as a helper for artists to search games for unlicensed use of their assets. It is not meant to encourage extraction with the sole purpose of using assets in your own products without permission of the copyright holder.

Remember: don't steal assets from other people's games. Respect copyrights. And don't protect your own games - it's unnecessary effort.