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{ lib, config, utils, pkgs, ... }:
with lib;
let
inherit (utils) systemdUtils escapeSystemdPath;
inherit (systemdUtils.lib)
generateUnits
pathToUnit
serviceToUnit
sliceToUnit
socketToUnit
targetToUnit
timerToUnit
mountToUnit
automountToUnit;
cfg = config.boot.initrd.systemd;
# Copied from fedora
upstreamUnits = [
"basic.target"
"ctrl-alt-del.target"
"emergency.service"
"emergency.target"
"final.target"
"halt.target"
"initrd-cleanup.service"
"initrd-fs.target"
"initrd-parse-etc.service"
"initrd-root-device.target"
"initrd-root-fs.target"
"initrd-switch-root.service"
"initrd-switch-root.target"
"initrd.target"
"initrd-udevadm-cleanup-db.service"
"kexec.target"
"kmod-static-nodes.service"
"local-fs-pre.target"
"local-fs.target"
"multi-user.target"
"paths.target"
"poweroff.target"
"reboot.target"
"rescue.service"
"rescue.target"
"rpcbind.target"
"shutdown.target"
"sigpwr.target"
"slices.target"
"sockets.target"
"swap.target"
"sysinit.target"
"sys-kernel-config.mount"
"syslog.socket"
"systemd-ask-password-console.path"
"systemd-ask-password-console.service"
"systemd-fsck@.service"
"systemd-halt.service"
"systemd-hibernate-resume@.service"
"systemd-journald-audit.socket"
"systemd-journald-dev-log.socket"
"systemd-journald.service"
"systemd-journald.socket"
"systemd-kexec.service"
"systemd-modules-load.service"
"systemd-poweroff.service"
"systemd-random-seed.service"
"systemd-reboot.service"
"systemd-sysctl.service"
"systemd-tmpfiles-setup-dev.service"
"systemd-tmpfiles-setup.service"
"systemd-udevd-control.socket"
"systemd-udevd-kernel.socket"
"systemd-udevd.service"
"systemd-udev-settle.service"
"systemd-udev-trigger.service"
"systemd-vconsole-setup.service"
"timers.target"
"umount.target"
# TODO: Networking
# "network-online.target"
# "network-pre.target"
# "network.target"
# "nss-lookup.target"
# "nss-user-lookup.target"
# "remote-fs-pre.target"
# "remote-fs.target"
] ++ cfg.additionalUpstreamUnits;
upstreamWants = [
"sysinit.target.wants"
];
enabledUpstreamUnits = filter (n: ! elem n cfg.suppressedUnits) upstreamUnits;
enabledUnits = filterAttrs (n: v: ! elem n cfg.suppressedUnits) cfg.units;
jobScripts = concatLists (mapAttrsToList (_: unit: unit.jobScripts or []) (filterAttrs (_: v: v.enable) cfg.services));
stage1Units = generateUnits {
type = "initrd";
units = enabledUnits;
upstreamUnits = enabledUpstreamUnits;
inherit upstreamWants;
inherit (cfg) packages package;
};
fileSystems = filter utils.fsNeededForBoot config.system.build.fileSystems;
fstab = pkgs.writeText "fstab" (lib.concatMapStringsSep "\n"
({ fsType, mountPoint, device, options, autoFormat, autoResize, ... }@fs: let
opts = options ++ optional autoFormat "x-systemd.makefs" ++ optional autoResize "x-systemd.growfs";
in "${device} /sysroot${mountPoint} ${fsType} ${lib.concatStringsSep "," opts}") fileSystems);
kernel-name = config.boot.kernelPackages.kernel.name or "kernel";
modulesTree = config.system.modulesTree.override { name = kernel-name + "-modules"; };
firmware = config.hardware.firmware;
# Determine the set of modules that we need to mount the root FS.
modulesClosure = pkgs.makeModulesClosure {
rootModules = config.boot.initrd.availableKernelModules ++ config.boot.initrd.kernelModules;
kernel = modulesTree;
firmware = firmware;
allowMissing = false;
};
initrdBinEnv = pkgs.buildEnv {
name = "initrd-emergency-env";
paths = map getBin cfg.initrdBin;
pathsToLink = ["/bin" "/sbin"];
# Make recovery easier
postBuild = ''
ln -s ${cfg.package.util-linux}/bin/mount $out/bin/
ln -s ${cfg.package.util-linux}/bin/umount $out/bin/
'';
};
initialRamdisk = pkgs.makeInitrdNG {
contents = map (path: { object = path; symlink = ""; }) (subtractLists cfg.suppressedStorePaths cfg.storePaths)
++ mapAttrsToList (_: v: { object = v.source; symlink = v.target; }) (filterAttrs (_: v: v.enable) cfg.contents);
};
in {
options.boot.initrd.systemd = {
enable = mkEnableOption ''systemd in initrd.
Note: This is in very early development and is highly
experimental. Most of the features NixOS supports in initrd are
not yet supported by the intrd generated with this option.
'';
package = (mkPackageOption pkgs "systemd" {
default = "systemdMinimal";
}) // {
visible = false;
};
contents = mkOption {
description = "Set of files that have to be linked into the initrd";
example = literalExpression ''
{
"/etc/hostname".text = "mymachine";
}
'';
visible = false;
default = {};
type = types.attrsOf (types.submodule ({ config, options, name, ... }: {
options = {
enable = mkEnableOption "copying of this file to initrd and symlinking it" // { default = true; };
target = mkOption {
type = types.path;
description = ''
Path of the symlink.
'';
default = name;
};
text = mkOption {
default = null;
type = types.nullOr types.lines;
description = "Text of the file.";
};
source = mkOption {
type = types.path;
description = "Path of the source file.";
};
};
config = {
source = mkIf (config.text != null) (
let name' = "initrd-" + baseNameOf name;
in mkDerivedConfig options.text (pkgs.writeText name')
);
};
}));
};
storePaths = mkOption {
description = ''
Store paths to copy into the initrd as well.
'';
type = types.listOf types.singleLineStr;
default = [];
};
suppressedStorePaths = mkOption {
description = ''
Store paths specified in the storePaths option that
should not be copied.
'';
type = types.listOf types.singleLineStr;
default = [];
};
emergencyAccess = mkOption {
type = with types; oneOf [ bool singleLineStr ];
visible = false;
description = ''
Set to true for unauthenticated emergency access, and false for
no emergency access.
Can also be set to a hashed super user password to allow
authenticated access to the emergency mode.
'';
default = false;
};
initrdBin = mkOption {
type = types.listOf types.package;
default = [];
visible = false;
description = ''
Packages to include in /bin for the stage 1 emergency shell.
'';
};
additionalUpstreamUnits = mkOption {
default = [ ];
type = types.listOf types.str;
visible = false;
example = [ "debug-shell.service" "systemd-quotacheck.service" ];
description = ''
Additional units shipped with systemd that shall be enabled.
'';
};
suppressedUnits = mkOption {
default = [ ];
type = types.listOf types.str;
example = [ "systemd-backlight@.service" ];
visible = false;
description = ''
A list of units to skip when generating system systemd configuration directory. This has
priority over upstream units, <option>boot.initrd.systemd.units</option>, and
<option>boot.initrd.systemd.additionalUpstreamUnits</option>. The main purpose of this is to
prevent a upstream systemd unit from being added to the initrd with any modifications made to it
by other NixOS modules.
'';
};
units = mkOption {
description = "Definition of systemd units.";
default = {};
visible = false;
type = systemdUtils.types.units;
};
packages = mkOption {
default = [];
visible = false;
type = types.listOf types.package;
example = literalExpression "[ pkgs.systemd-cryptsetup-generator ]";
description = "Packages providing systemd units and hooks.";
};
targets = mkOption {
default = {};
visible = false;
type = systemdUtils.types.initrdTargets;
description = "Definition of systemd target units.";
};
services = mkOption {
default = {};
type = systemdUtils.types.initrdServices;
visible = false;
description = "Definition of systemd service units.";
};
sockets = mkOption {
default = {};
type = systemdUtils.types.initrdSockets;
visible = false;
description = "Definition of systemd socket units.";
};
timers = mkOption {
default = {};
type = systemdUtils.types.initrdTimers;
visible = false;
description = "Definition of systemd timer units.";
};
paths = mkOption {
default = {};
type = systemdUtils.types.initrdPaths;
visible = false;
description = "Definition of systemd path units.";
};
mounts = mkOption {
default = [];
type = systemdUtils.types.initrdMounts;
visible = false;
description = ''
Definition of systemd mount units.
This is a list instead of an attrSet, because systemd mandates the names to be derived from
the 'where' attribute.
'';
};
automounts = mkOption {
default = [];
type = systemdUtils.types.automounts;
visible = false;
description = ''
Definition of systemd automount units.
This is a list instead of an attrSet, because systemd mandates the names to be derived from
the 'where' attribute.
'';
};
slices = mkOption {
default = {};
type = systemdUtils.types.slices;
visible = false;
description = "Definition of slice configurations.";
};
};
config = mkIf (config.boot.initrd.enable && cfg.enable) {
system.build = { inherit initialRamdisk; };
boot.initrd.systemd = {
initrdBin = [pkgs.bash pkgs.coreutils pkgs.kmod cfg.package] ++ config.system.fsPackages;
contents = {
"/init".source = "${cfg.package}/lib/systemd/systemd";
"/etc/systemd/system".source = stage1Units;
"/etc/systemd/system.conf".text = ''
[Manager]
DefaultEnvironment=PATH=/bin:/sbin
'';
"/etc/fstab".source = fstab;
"/lib/modules".source = "${modulesClosure}/lib/modules";
"/etc/modules-load.d/nixos.conf".text = concatStringsSep "\n" config.boot.initrd.kernelModules;
"/etc/passwd".source = "${pkgs.fakeNss}/etc/passwd";
"/etc/shadow".text = "root:${if isBool cfg.emergencyAccess then "!" else cfg.emergencyAccess}:::::::";
"/bin".source = "${initrdBinEnv}/bin";
"/sbin".source = "${initrdBinEnv}/sbin";
"/etc/sysctl.d/nixos.conf".text = "kernel.modprobe = /sbin/modprobe";
};
storePaths = [
# TODO: Limit this to the bare necessities
"${cfg.package}/lib"
"${cfg.package.util-linux}/bin/mount"
"${cfg.package.util-linux}/bin/umount"
"${cfg.package.util-linux}/bin/sulogin"
# so NSS can look up usernames
"${pkgs.glibc}/lib/libnss_files.so"
] ++ jobScripts;
targets.initrd.aliases = ["default.target"];
units =
mapAttrs' (n: v: nameValuePair "${n}.path" (pathToUnit n v)) cfg.paths
// mapAttrs' (n: v: nameValuePair "${n}.service" (serviceToUnit n v)) cfg.services
// mapAttrs' (n: v: nameValuePair "${n}.slice" (sliceToUnit n v)) cfg.slices
// mapAttrs' (n: v: nameValuePair "${n}.socket" (socketToUnit n v)) cfg.sockets
// mapAttrs' (n: v: nameValuePair "${n}.target" (targetToUnit n v)) cfg.targets
// mapAttrs' (n: v: nameValuePair "${n}.timer" (timerToUnit n v)) cfg.timers
// listToAttrs (map
(v: let n = escapeSystemdPath v.where;
in nameValuePair "${n}.mount" (mountToUnit n v)) cfg.mounts)
// listToAttrs (map
(v: let n = escapeSystemdPath v.where;
in nameValuePair "${n}.automount" (automountToUnit n v)) cfg.automounts);
services.emergency = mkIf (isBool cfg.emergencyAccess && cfg.emergencyAccess) {
environment.SYSTEMD_SULOGIN_FORCE = "1";
};
# The unit in /run/systemd/generator shadows the unit in
# /etc/systemd/system, but will still apply drop-ins from
# /etc/systemd/system/foo.service.d/
#
# We need IgnoreOnIsolate, otherwise the Requires dependency of
# a mount unit on its makefs unit causes it to be unmounted when
# we isolate for switch-root. Use a dummy package so that
# generateUnits will generate drop-ins instead of unit files.
packages = [(pkgs.runCommand "dummy" {} ''
mkdir -p $out/etc/systemd/system
touch $out/etc/systemd/system/systemd-{makefs,growfs}@.service
'')];
services."systemd-makefs@".unitConfig.IgnoreOnIsolate = true;
services."systemd-growfs@".unitConfig.IgnoreOnIsolate = true;
};
};
}
|