{ config, lib, pkgs, ... }:
with lib;
let
inherit (pkgs) stdenv writeText procps;
udev = config.systemd.package;
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"
# Needed for gpm.
SUBSYSTEM=="input", KERNEL=="mice", TAG+="systemd"
'';
# Perform substitutions in all udev rules files.
udevRules = stdenv.mkDerivation {
name = "udev-rules";
preferLocalBuild = true;
allowSubstitutes = false;
buildCommand = ''
mkdir -p $out
shopt -s nullglob
set +o pipefail
# 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)"
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
${optionalString config.networking.usePredictableInterfaceNames ''
cp ${./80-net-setup-link.rules} $out/80-net-setup-link.rules
''}
# If auto-configuration is disabled, then remove
# udev's 80-drivers.rules file, which contains rules for
# automatically calling modprobe.
${optionalString (!config.boot.hardwareScan) ''
ln -s /dev/null $out/80-drivers.rules
''}
''; # */
};
# 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 {
type = types.bool;
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 {
type = types.listOf types.path;
default = [];
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 {
type = types.listOf types.path;
default = [];
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 = types.lines;
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 {
type = types.listOf types.path;
default = [];
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 <filename>/root/test-firmware</filename>
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;
};
};
networking.usePredictableInterfaceNames = mkOption {
default = true;
type = types.bool;
description = ''
Whether to assign <link
xlink:href='http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames'>predictable
names to network interfaces</link>. If enabled, interfaces
are assigned names that contain topology information
(e.g. <literal>wlp3s0</literal>) and thus should be stable
across reboots. If disabled, names depend on the order in
which interfaces are discovered by the kernel, which may
change randomly across reboots; for instance, you may find
<literal>eth0</literal> and <literal>eth1</literal> flipping
unpredictably.
'';
};
};
###### implementation
config = mkIf (!config.boot.isContainer) {
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")
];
boot.extraModprobeConfig = "options firmware_class path=${config.hardware.firmware}";
system.activationScripts.udevd =
''
# The deprecated hotplug uevent helper is not used anymore
if [ -e /proc/sys/kernel/hotplug ]; then
echo "" > /proc/sys/kernel/hotplug
fi
# Regenerate the hardware database /var/lib/udev/hwdb.bin
# whenever systemd changes.
if [ ! -e /var/lib/udev/prev-systemd -o "$(readlink /var/lib/udev/prev-systemd)" != ${config.systemd.package} ]; then
echo "regenerating udev hardware database..."
${config.systemd.package}/bin/udevadm hwdb --update && ln -sfn ${config.systemd.package} /var/lib/udev/prev-systemd
fi
# Allow the kernel to find our firmware.
if [ -e /sys/module/firmware_class/parameters/path ]; then
echo -n "${config.hardware.firmware}" > /sys/module/firmware_class/parameters/path
fi
'';
systemd.services.systemd-udevd =
{ environment.MODULE_DIR = "/run/booted-system/kernel-modules/lib/modules";
};
};
}