Sonic Galactic (Demo 2) .hatch file

[Bobblox21]

There's this archive made with an open-source game engine called Hatch from Github which uses OpenMania (Sonic Mania mod stuff e.t.c) source code and i can't get to open it using RetroED nor extracting it using RSDK_v5 extracting tools cause it uses the "HATCH" header instead of "RSDK"

Sample file:
Data.hatch

is there a way to decompress these files for dumping the resources like (image, sprites, sound and models e.t.c) cause i found some references here:
https://github.com/Axanery/HatchGameEngine
https://github.com/Axanery/OpenMania


 

[ikskoks]

Hi. File format looks like this:
 

// header
5 bytes (char) - signature // "HATCH"
3 bytes - version  // 01 00 00

// index
2 bytes (uint16) - file count
// for each file
  4 bytes (uint32) - filename CRC32
  8 bytes (uint64) - file offset
  8 bytes (uint64) - file uncompressed size
  4 bytes (uint32) - data flag  // 2 - encrypted, 0 - not encrypted
  8 bytes (uint64) - file compressed size

// data
// for each file
  x bytes - file data

And here's a script to dump and decompress file data.

https://github.com/bartlomiejduda/Tools/blob/master/NEW Tools/Hatch Engine/Hatch_Engine_HATCH_script.bms

 

Unfortunately all files with dataFlag=2 are encrypted. If I understand engine's source code corretly, you need original filenames and original file sizes to properly decrypt data.
Here's the algorithm to decrypt:
https://github.com/Axanery/HatchGameEngine/blob/master/source/Engine/ResourceTypes/ResourceManager.cpp#L172-L232

You can probably hook the game with Frida to get the filenames.

[ikskoks]

Luckily this "Sonic Galactic" game had debug symbols in "demo 2" release 😄 
So it was very easy to create frida hook

https://github.com/bartlomiejduda/Tools/blob/master/NEW Tools/Hatch Engine/hatch_engine_frida_script.js

And I have 574 filenames already:
 

sonic_galactic_filenames_FINAL.zip

[ikskoks]

It's possible to get some assets after making use of the filenames I shared above:

 

Here's my implementation of the decryption algorithm:
https://github.com/bartlomiejduda/ReverseBox/blob/main/reversebox/encryption/encryption_hatch_engine.py

I'm also working on a extractor for this game, but I'll share it when it will be more user friendly 😄 

[ikskoks]

Currently 1394 filenames are known

2025-01-05 01:41:02 - __main__ - line 109 - INFO - ####### SUMMARY #######
2025-01-05 01:41:02 - __main__ - line 112 - INFO - Known filenames: 1394 (61.76%)
2025-01-05 01:41:02 - __main__ - line 113 - INFO - Unknown filenames: 863 (38.24%)
2025-01-05 01:41:02 - __main__ - line 114 - INFO - All filenames: 2257

Full list available here:

https://github.com/bartlomiejduda/Tools/blob/master/NEW Tools/Hatch Engine/Hatch Engine Archive Tool/filelists/sonic_galactic_demo2_filenames.txt

[ikskoks]

Extractor for data.hatch archive is available here:

https://github.com/bartlomiejduda/Tools/tree/master/NEW Tools/Hatch Engine/Hatch Engine Archive Tool

 

[ikskoks]

Thanks to anonymous user we have now over 90% of the filenames. 😉 
 

2025-01-05 21:17:54 - __main__ - line 109 - INFO - ####### SUMMARY #######
2025-01-05 21:17:54 - __main__ - line 112 - INFO - Known filenames: 2039 (90.34%)
2025-01-05 21:17:54 - __main__ - line 113 - INFO - Unknown filenames: 218 (9.66%)
2025-01-05 21:17:54 - __main__ - line 114 - INFO - All filenames: 2257