PAK (File Format)/RetroStudios

PAK is an archive file format used in games such as Donkey Kong Country Returns created by RetroStudios.

File Format

Header

The file starts with the following header:

Offset	Type	Description
0x00	UInt32	Unknown. Always 2, possibly a version number.
0x04	UInt32	Header size. Always 0x40.
0x08	Byte[0x10]	MD5 hash of the file data following the header.
0x18	Byte[0x18]	Padding.

Table Of Content

After the header, a table of content structure specify what sections are stored in the file. It has the following structure:

Offset	Type	Description
0x00	UInt32	Section count (N). In practice this will always be 3 with order STRG, RSHD, DATA.

N entries of the following structure follows.

Offset	Type	Description
0x00	Char[4]	Section magic.
0x04	UInt32	Section size in bytes.

Afterwards the section data is layout in the same order as they are specified above.

STRG

The STRG data starts with the following structure:

Offset	Type	Description
0x00	UInt32	Number of named resources (N).

Immediately afterwards N named resources follows.

Named Resource

Each resource has the following structure:

Offset	Type	Description
0x00	Char[N + 1]	Resource name stored as a null-terminated string of length N.
N + 1	Char[4]	Resource magic. File magic of the resource specifying file type.
N + 5	UInt64	Resource ID.

RSHD

The RSHD data starts with the following structure:

Offset	Type	Description
0x00	UInt32	Number of resources (N).

Immediately afterwards N resources follows.

Resource

Each resource has the following structure:

Offset	Type	Description
0x00	UInt32	Compression flag. Either 0 (uncompressed) or 1 (compressed).
0x04	Char[4]	Resource magic. File magic of the resource specifying file type.
0x08	UInt64	Resource ID.
0x10	UInt32	File data size in bytes.
0x14	UInt32	File data offset, relative to the start of the DATA section.

DATA

All file data is stored in the DATA section and references by each resource.

Tools

The following tools can handle PAK files:

• crPakTool by jellees