3.3 KiB
nix-openwrt-imagebuilder
Generate OpenWRT images from Nix derivations using the official ImageBuilders that are provided upstream.
For OpenWRT releases since 19.07 there is profile helper functionality that helps you find the proper image specification (target, variant) according to your hardware's profile name.
Background
In an ideal world, OpenWRT would be built from source in many fine-grained Nix derivations. Until someone implements that (please do!), this project exists to reuse the binary ImageBuilders that are included in every OpenWRT release. They are only available for x86_64-linux hosts.
The ImageBuilder can generate new sysupgrade images with a customized set of packages and included files. Caveat: It cannot build factory images for a first-time installation on the vendor firmware.
Usage with vanilla Nix
let
openwrt-imagebuilder = ../nix-openwrt-imagebuilder;
openwrtSystem = import (openwrt-imagebuilder + "/lib/openwrt-system.nix");
sys = openwrtSystem {
pkgs = import <nixpkgs> { };
modules = [
({ pkgs, ... }: {
# find target/variant for an old Fritzbox
system.profile = "avm_fritz7412";
# add package to include in the image, ie. packages that you don't
# want to install manually later
packages = [ "tcpdump" ];
services.disabled = [ "dnsmasq" ];
# include files in the images.
# to set UCI configuration, create a uci-defauts scripts as per
# official OpenWRT ImageBuilder recommendation.
files = pkgs.runCommandNoCC "image-files" { } ''
mkdir -p $out/etc/uci-defaults
cat > $out/etc/uci-defaults/99-custom <<EOF
uci -q batch << EOI
set system.@system[0].hostname='testap'
commit
EOI
EOF
'';
})
];
};
# actually build the image
in sys.config.system.build.image
Usage with Nix Flakes
{
inputs = {
openwrt-imagebuilder.url = "github:astro/nix-openwrt-imagebuilder";
};
outputs = { self, nixpkgs, openwrt-imagebuilder }: {
packages.x86_64-linux.my-router = let
sys = openwrt-imagebuilder.lib.openwrtSystem {
pkgs = nixpkgs.legacyPackages.x86_64-linux;
modules = [
({ pkgs, ... }: {
system.profile = "avm_fritz7412";
# add package to include in the image, ie. packages that you don't
# want to install manually later
packages = [ "tcpdump" ];
services.disabled = [ "dnsmasq" ];
# include files in the images.
# to set UCI configuration, create a uci-defauts scripts as per
# official OpenWRT ImageBuilder recommendation.
files = pkgs.runCommandNoCC "image-files" { } ''
mkdir -p $out/etc/uci-defaults
cat > $out/etc/uci-defaults/99-custom <<EOF
uci -q batch << EOI
set system.@system[0].hostname='testap'
commit
EOI
EOF
'';
})
];
};
in sys.config.system.build.image;
};
}
Refreshing hashes
Checksums of the sha256sums
files on downloads.openwrt.org are added
to this repository for a few recent releases. To update them, run:
nix-shell -p nixFlakes
nix run .#generate-hashes 21.02.3 # for example
git add hashes/*.nix