resleriana_tools

Tool to play around with Atelier Resleriana ( レスレリアーナのアトリエ ) encrypted AssetBundle files

File Format

Header

Name	Size	Type	Default	Comment
Magic Number	4	[]byte	"Aktk"
Version	2	uint16	0x01
Reserved	2	uint16	0x00	Why does the game checks it must be 0, what's the purpose
Encryption	4	enum	0x01	0x00 => None, 0x01 => Encrypted
MD5 Checksum	16	[]byte		Hash of the rest of the file whether the file encrypted or not

Encryption

A modified version of HChaCha which generates 512-bytes xor block. Each block generation do 8 normal HChaCha block generation with chained initial state.
I'll explain details of the format later, you can check out ./encryptor/keygen.go for details.

Caution

Unsafe zero-copy type conversion is used to improve performance

Load from resleriana_tools_config.json and compatible with linux and windows

First time execute will jump error：

FetchCatalog data: AccessDenied... ...... Unmarshal error: invalid character '<' looking for beginning of value ...... Failed to fetch catalog: invalid character '<' looking for beginning of value

Bacause resleriana_tools_config.json file will content: { "fetch_url": "https://asset.resleriana.com/asset/AssetsVersion/Android/" }

You need replace AssetsVersion to found version string by yourself. Then execute again without compile.