nixos/boot: add postResumeCommands option

Adds a postResumeCommands option to the initramfs to allow inserting
code to execute after the device has attempted to resume, and before
filesystems are mounted. This allows to inject code for operations like
wiping the rootfs on boot; if those were instead put in
postDeviceCommands, on a hibernated device, they would execute before
the device resumes from hibernation.

3 files changed, 12 insertions, 1 deletions

diff --git a/nixos/modules/system/boot/stage-1-init.sh b/nixos/modules/system/boot/stage-1-init.sh
index bc2fc7f7b108..06b6aff23272 100644
--- a/nixos/modules/system/boot/stage-1-init.sh
+++ b/nixos/modules/system/boot/stage-1-init.sh
@@ -498,6 +498,8 @@ if test -e /sys/power/resume -a -e /sys/power/disk; then
     fi
 fi
 
+@postResumeCommands@
+
 # If we have a path to an iso file, find the iso and link it to /dev/root
 if [ -n "$isoPath" ]; then
   mkdir -p /findiso
diff --git a/nixos/modules/system/boot/stage-1.nix b/nixos/modules/system/boot/stage-1.nix
index a3551f68dbe8..f981b4c17aac 100644
--- a/nixos/modules/system/boot/stage-1.nix
+++ b/nixos/modules/system/boot/stage-1.nix
@@ -316,7 +316,7 @@ let
     inherit (config.system.build) earlyMountScript;
 
     inherit (config.boot.initrd) checkJournalingFS verbose
-      preLVMCommands preDeviceCommands postDeviceCommands postMountCommands preFailCommands kernelModules;
+      preLVMCommands preDeviceCommands postDeviceCommands postResumeCommands postMountCommands preFailCommands kernelModules;
 
     resumeDevices = map (sd: if sd ? device then sd.device else "/dev/disk/by-label/${sd.label}")
                     (filter (sd: hasPrefix "/dev/" sd.device && !sd.randomEncryption.enable
@@ -524,6 +524,14 @@ in
       '';
     };
 
+    boot.initrd.postResumeCommands = mkOption {
+      default = "";
+      type = types.lines;
+      description = lib.mdDoc ''
+        Shell commands to be executed immediately after attempting to resume.
+      '';
+    };
+
     boot.initrd.postMountCommands = mkOption {
       default = "";
       type = types.lines;
diff --git a/nixos/modules/system/boot/systemd/initrd.nix b/nixos/modules/system/boot/systemd/initrd.nix
index be40b8e969a1..e223451652b2 100644
--- a/nixos/modules/system/boot/systemd/initrd.nix
+++ b/nixos/modules/system/boot/systemd/initrd.nix
@@ -358,6 +358,7 @@ in {
       [ "preDeviceCommands" ]
       [ "preLVMCommands" ]
       [ "postDeviceCommands" ]
+      [ "postResumeCommands" ]
       [ "postMountCommands" ]
       [ "extraUdevRulesCommands" ]
       [ "extraUtilsCommands" ]