rkimg

Minimal Rockchip image pack/unpack utility in C with a cross-platform CLI.

This implements a small, practical subset of Rockchip firmware image handling:

• unpack RKFW firmware images
• pack RKFW firmware images
• list RKFW and RKAF image contents as YAML without unpacking
• unpack standalone RKAF update images
• pack standalone RKAF update images
• unpack nested RKAF payloads found inside RKFW
• rebuild nested RKAF payloads during RKFW packing

It is intentionally narrow. Broader second-layer format handling is not implemented here.

Build

Linux or macOS

make

Cross-platform with CMake

cmake -S . -B build
cmake --build build

Releases

GitHub Actions builds release archives for Linux and Windows.

• pushes and pull requests run CI builds
• pushing a tag like v1.0.0 publishes a GitHub Release with packaged binaries

Usage

Linux or macOS:

./rkimg unpack input.img outdir
./rkimg pack outdir rebuilt.img
./rkimg list input.img

Windows:

.\build\Debug\rkimg.exe unpack input.img outdir
.\build\Debug\rkimg.exe pack outdir rebuilt.img
.\build\Debug\rkimg.exe list input.img

list prints YAML describing the container structure, headers, nested entries, and detected second-layer wrappers without extracting files.

Unpack Layout

For RKFW images:

outdir/
  manifest.ini
  loader.bin
  update.img
  update/
    manifest.ini
    files/...

For standalone RKAF images:

outdir/
  manifest.ini
  files/...

Manifest Notes

manifest.ini stores only the fields needed for minimal round-tripping.

• RKFW manifests include timestamp/header fields plus loader_file, update_file, append_md5, and optional update_dir when the payload was unpacked as nested RKAF.
• RKAF manifests include image metadata plus [entryN] sections for each file table entry.

Limitations

• SELF entries are rejected on pack. Those images need extra handling that this minimal utility does not currently replicate.
• RESERVED entries are preserved as metadata-only table entries.
• Extracted file payloads are written as stored in the image.
• Checksum mismatches during unpack are warnings, not hard failures.