nixpkgs/modules/services/hardware/udev.nix

206 lines
6.1 KiB
Nix

{ config, pkgs, ... }:
with pkgs.lib;
let
inherit (pkgs) stdenv writeText procps;
udev = config.system.build.systemd;
cfg = config.services.udev;
extraUdevRules = pkgs.writeTextFile {
name = "extra-udev-rules";
text = cfg.extraRules;
destination = "/etc/udev/rules.d/10-local.rules";
};
nixosRules = ''
# Miscellaneous devices.
KERNEL=="kvm", MODE="0666"
KERNEL=="kqemu", MODE="0666"
'';
# Perform substitutions in all udev rules files.
udevRules = stdenv.mkDerivation {
name = "udev-rules";
buildCommand = ''
mkdir -p $out
shopt -s nullglob
# Set a reasonable $PATH for programs called by udev rules.
echo 'ENV{PATH}="${udevPath}/bin:${udevPath}/sbin"' > $out/00-path.rules
# Add the udev rules from other packages.
for i in ${toString cfg.packages}; do
echo "Adding rules for package $i"
for j in $i/{etc,lib}/udev/rules.d/*; do
echo "Copying $j to $out/$(basename $j)"
echo "# Copied from $j" > $out/$(basename $j)
cat $j >> $out/$(basename $j)
done
done
# Fix some paths in the standard udev rules. Hacky.
for i in $out/*.rules; do
substituteInPlace $i \
--replace \"/sbin/modprobe \"${config.system.sbin.modprobe}/sbin/modprobe \
--replace \"/sbin/mdadm \"${pkgs.mdadm}/sbin/mdadm \
--replace \"/sbin/blkid \"${pkgs.utillinux}/sbin/blkid \
--replace \"/bin/mount \"${pkgs.utillinux}/bin/mount
done
echo -n "Checking that all programs called by relative paths in udev rules exist in ${udev}/lib/udev... "
import_progs=$(grep 'IMPORT{program}="[^/$]' $out/* |
sed -e 's/.*IMPORT{program}="\([^ "]*\)[ "].*/\1/' | uniq)
run_progs=$(grep -v '^[[:space:]]*#' $out/* | grep 'RUN+="[^/$]' |
sed -e 's/.*RUN+="\([^ "]*\)[ "].*/\1/' | uniq)
for i in $import_progs $run_progs; do
if [[ ! -x ${pkgs.udev}/lib/udev/$i && ! $i =~ socket:.* ]]; then
echo "FAIL"
echo "$i is called in udev rules but not installed by udev"
exit 1
fi
done
echo "OK"
echo -n "Checking that all programs called by absolute paths in udev rules exist... "
import_progs=$(grep 'IMPORT{program}="\/' $out/* |
sed -e 's/.*IMPORT{program}="\([^ "]*\)[ "].*/\1/' | uniq)
run_progs=$(grep -v '^[[:space:]]*#' $out/* | grep 'RUN+="/' |
sed -e 's/.*RUN+="\([^ "]*\)[ "].*/\1/' | uniq)
for i in $import_progs $run_progs; do
if [[ ! -x $i ]]; then
echo "FAIL"
echo "$i is called in udev rules but not installed by udev"
exit 1
fi
done
echo "OK"
echo "Consider fixing the following udev rules:"
for i in ${toString cfg.packages}; do
grep -l '\(RUN+\|IMPORT{program}\)="\(/usr\)\?/s\?bin' $i/*/udev/rules.d/* || true
done
''; # */
};
# Udev has a 512-character limit for ENV{PATH}, so create a symlink
# tree to work around this.
udevPath = pkgs.buildEnv {
name = "udev-path";
paths = cfg.path;
pathsToLink = [ "/bin" "/sbin" ];
ignoreCollisions = true;
};
in
{
###### interface
options = {
boot.hardwareScan = mkOption {
default = true;
description = ''
Whether to try to load kernel modules for all detected hardware.
Usually this does a good job of providing you with the modules
you need, but sometimes it can crash the system or cause other
nasty effects.
'';
};
services.udev = {
packages = mkOption {
default = [];
merge = mergeListOption;
description = ''
List of packages containing <command>udev</command> rules.
All files found in
<filename><replaceable>pkg</replaceable>/etc/udev/rules.d</filename> and
<filename><replaceable>pkg</replaceable>/lib/udev/rules.d</filename>
will be included.
'';
};
path = mkOption {
default = [];
merge = mergeListOption;
description = ''
Packages added to the <envar>PATH</envar> environment variable when
executing programs from Udev rules.
'';
};
extraRules = mkOption {
default = "";
example = ''
KERNEL=="eth*", ATTR{address}=="00:1D:60:B9:6D:4F", NAME="my_fast_network_card"
'';
type = with pkgs.lib.types; string;
description = ''
Additional <command>udev</command> rules. They'll be written
into file <filename>10-local.rules</filename>. Thus they are
read before all other rules.
'';
};
};
hardware.firmware = mkOption {
default = [];
example = [ "/root/my-firmware" ];
merge = mergeListOption;
description = ''
List of directories containing firmware files. Such files
will be loaded automatically if the kernel asks for them
(i.e., when it has detected specific hardware that requires
firmware to function). If more than one path contains a
firmware file with the same name, the first path in the list
takes precedence. Note that you must rebuild your system if
you add files to any of these directories. For quick testing,
put firmware files in /root/test-firmware and add that
directory to the list.
Note that you can also add firmware packages to this
list as these are directories in the nix store.
'';
apply = list: pkgs.buildEnv {
name = "firmware";
paths = list;
pathsToLink = [ "/" ];
ignoreCollisions = true;
};
};
};
###### implementation
config = {
services.udev.extraRules = nixosRules;
services.udev.packages = [ extraUdevRules ];
services.udev.path = [ pkgs.coreutils pkgs.gnused pkgs.gnugrep pkgs.utillinux udev ];
environment.etc =
[ { source = udevRules;
target = "udev/rules.d";
}
];
system.requiredKernelConfig = with config.lib.kernelConfig; [
(isEnabled "UNIX")
(isYes "INOTIFY_USER")
(isYes "NET")
];
};
}