ALAS Decryptor

This Python 3 script decrypts ALAS files from the Wii's Region Select channel (rgnsel). Thanks to Larsenv from RiiConnect24 for figuring out the keys, the format and creating the initial script!

Usage

1. Install PyCryptodome
2. Put your encrypted ALAS files in the subdirectory "address" of this script
3. Run decryptor.py
4. Your decrypted ALAS files are in the "address/decrypted" directory!

And after that?

1. Decompress the LZ77 U8 archive with DSDecmp (dsdecmp ALAS_FILE)
2. Extract the U8 archive with ShowMiiWads, U8Tool or Wiimms SZS Tools (wszst x ALAS_FILE)

Technical stuff

1. Remove the first 320 bytes (the RSA signature) from the ALAS file
2. Decrypt it with AES-256-CBC mode and the key FF4C1AE3D4FFD236712E258A1F0B91E72C9125B0DF94C1691BCEF13011F16C0F with 862D7D8676A630A82972AB9735E1A5CE as initialization vector
3. Remove the first 32 bytes from the decrypted data and you get an LZ77-compressed U8 archive

More?

• Check out the WiiDatabase Wiki (German)!
• Use WiiConnect24 again with RiiConnect24!