This is a Rust re-implementation of [extract-ikconfig] from Linux kernel, to extract the .config file from a kernel image.
This will only work when the kernel was compiled with CONFIG_IKCONFIG.
This crate requires liblzma being present in the system before installation.
sudo pacman -S xz
sudo apt install liblzma-dev
Please refer to system manuals for other distributions. You can check if liblzma is installed by using pkg-config:
$ pkg-config --libs liblzma
-llzma
This crate has been published onto crates.io, so you can use the following command to install ikconfig executable in ~/.cargo/bin directory:
cargo install ikconfig
ikconfig /boot/vmlinuz-linux
The extracted config file will be printed on standard output as the original shell script does. Please use output redirection to save as a file if needed:
ikconfig /boot/vmlinuz-linux > .config
I haven't managed to make LZO decompression working yet, so if the kernel is compiled with CONFIG_KERNEL_LZO, ikconfig won't work. Please use the shell script [extract-ikconfig] from Linux kernel for now.
Because Linux kernel uses legacy frame format, but the LZ4 decompression library I used (lz4_flex) doesn't support it yet.
I added the support of decoding legacy frames in my fork and used it for ikconfig, but crates.io still pull the original one, which is reasonable.
So for now, if you want to extract .config file from a kernel compiled with CONFIG_KERNEL_LZ4, you could either use the shell script [extract-ikconfig] from Linux kernel, or clone ikconfig source code and install from there:
git clone --recursive https://github.com/yestyle/extract-ikconfig-rs
cd extract-ikconfig-rs
cargo install --path .
Because crates.io has a upload size limit of 10 MiB, the test cases and data are moved to tests branch.
This project is licensed under GPL-3.0 or MIT license.