GFAC files are archive files.

File Format

Header

Offset Size Type Description
0x00 4 char[4] Magic Word 'GFAC'
0x04 4 uint32 Version?
0x08 4 uint32 Always 1
0x0C 4 uint32 Absolut offset of file table
0x10 4 uint32 Size of file table
0x14 4 uint32 Absolut offset of file data
0x18 4 uint32 Size of file data
0x1C 16 Padding/Unknown

File Table

Offset Size Type Description
0x00 4 uint32 Entry count / Number of files
Entry
4 uint32 CRC-32 ?
4 uint32 Absolut offset of file name
4 uint32 file size
4 uint32 file offset

The file offset refers to the raw file data. If a container like GFCP is used the data has to be decompressed and must replace the whole container.