feat(tmpfiles): defer per-service file permissions to reduce boot time

modules/lib.nix

@@ -155,5 +155,28 @@ inputs.nixpkgs.lib.extend (
         #  }
         #];
       };
+
+    serviceFilePerms =
+      serviceName: tmpfilesRules:
+      { pkgs, ... }:
+      let
+        confFile = pkgs.writeText "${serviceName}-file-perms.conf" (lib.concatStringsSep "\n" tmpfilesRules);
+      in
+      {
+        systemd.services."${serviceName}-file-perms" = {
+          after = [ "${serviceName}-mounts.service" ];
+          before = [ "${serviceName}.service" ];
+          serviceConfig = {
+            Type = "oneshot";
+            RemainAfterExit = true;
+            ExecStart = "${pkgs.systemd}/bin/systemd-tmpfiles --create ${confFile}";
+          };
+        };
+
+        systemd.services.${serviceName} = {
+          wants = [ "${serviceName}-file-perms.service" ];
+          after = [ "${serviceName}-file-perms.service" ];
+        };
+      };
   }
 )

services/bitwarden.nix

@@ -15,6 +15,10 @@
       service_configs.vaultwarden.path
       config.services.vaultwarden.backupDir
     ])
+    (lib.serviceFilePerms "vaultwarden" [
+      "Z ${service_configs.vaultwarden.path} 0700 vaultwarden vaultwarden"
+      "Z ${config.services.vaultwarden.backupDir} 0700 vaultwarden vaultwarden"
+    ])
   ];
 
   services.vaultwarden = {
@@ -39,11 +43,6 @@
     }
   '';
 
-  systemd.tmpfiles.rules = [
-    "Z ${service_configs.vaultwarden.path} 0700 vaultwarden vaultwarden"
-    "Z ${config.services.vaultwarden.backupDir} 0700 vaultwarden vaultwarden"
-  ];
-
   # Protect Vaultwarden login from brute force attacks
   services.fail2ban.jails.vaultwarden = {
     enabled = true;

services/gitea.nix

@@ -8,6 +8,9 @@
 {
   imports = [
     (lib.serviceMountWithZpool "gitea" service_configs.zpool_ssds [ config.services.gitea.stateDir ])
+    (lib.serviceFilePerms "gitea" [
+      "Z ${config.services.gitea.stateDir} 0700 ${config.services.gitea.user} ${config.services.gitea.group}"
+    ])
   ];
 
   services.gitea = {
@@ -41,11 +44,6 @@
     reverse_proxy :${builtins.toString config.services.gitea.settings.server.HTTP_PORT}
   '';
 
-  systemd.tmpfiles.rules = [
-    # 0700 for ssh permission reasons
-    "Z ${config.services.gitea.stateDir} 0700 ${config.services.gitea.user} ${config.services.gitea.group}"
-  ];
-
   services.postgresql = {
     ensureDatabases = [ config.services.gitea.user ];
     ensureUsers = [

services/immich.nix

@@ -13,6 +13,9 @@
     (lib.serviceMountWithZpool "immich-machine-learning" service_configs.zpool_ssds [
       config.services.immich.mediaLocation
     ])
+    (lib.serviceFilePerms "immich-server" [
+      "Z ${config.services.immich.mediaLocation} 0770 ${config.services.immich.user} ${config.services.immich.group}"
+    ])
   ];
 
   services.immich = {
@@ -30,10 +33,6 @@
     reverse_proxy :${builtins.toString config.services.immich.port}
   '';
 
-  systemd.tmpfiles.rules = [
-    "Z ${config.services.immich.mediaLocation} 0770 ${config.services.immich.user} ${config.services.immich.group}"
-  ];
-
   environment.systemPackages = with pkgs; [
     immich-go
   ];

services/jellyfin.nix

@@ -11,6 +11,10 @@
       config.services.jellyfin.dataDir
       config.services.jellyfin.cacheDir
     ])
+    (lib.serviceFilePerms "jellyfin" [
+      "Z ${config.services.jellyfin.dataDir} 0700 ${config.services.jellyfin.user} ${config.services.jellyfin.group}"
+      "Z ${config.services.jellyfin.cacheDir} 0700 ${config.services.jellyfin.user} ${config.services.jellyfin.group}"
+    ])
   ];
 
   services.jellyfin = {
@@ -33,11 +37,6 @@
     }
   '';
 
-  systemd.tmpfiles.rules = [
-    "Z ${config.services.jellyfin.dataDir} 0700 ${config.services.jellyfin.user} ${config.services.jellyfin.group}"
-    "Z ${config.services.jellyfin.cacheDir} 0700 ${config.services.jellyfin.user} ${config.services.jellyfin.group}"
-  ];
-
   users.users.${config.services.jellyfin.user}.extraGroups = [
     "video"
     "render"

services/matrix.nix

@@ -9,6 +9,9 @@
     (lib.serviceMountWithZpool "continuwuity" service_configs.zpool_ssds [
       "/var/lib/private/continuwuity"
     ])
+    (lib.serviceFilePerms "continuwuity" [
+      "Z /var/lib/private/continuwuity 0770 ${config.services.matrix-continuwuity.user} ${config.services.matrix-continuwuity.group}"
+    ])
   ];
 
   services.matrix-continuwuity = {
@@ -58,10 +61,6 @@
   services.caddy.virtualHosts."${service_configs.matrix.domain}:${builtins.toString service_configs.ports.matrix_federation}".extraConfig =
     config.services.caddy.virtualHosts."${service_configs.matrix.domain}".extraConfig;
 
-  systemd.tmpfiles.rules = [
-    "Z /var/lib/private/continuwuity 0770 ${config.services.matrix-continuwuity.user} ${config.services.matrix-continuwuity.group}"
-  ];
-
   # for federation
   networking.firewall.allowedTCPPorts = [
     service_configs.ports.matrix_federation

services/minecraft.nix

@@ -15,6 +15,10 @@
       ]
     )
     inputs.nix-minecraft.nixosModules.minecraft-servers
+    (lib.serviceFilePerms "minecraft-server-${service_configs.minecraft.server_name}" [
+      "Z ${service_configs.minecraft.parent_dir}/${service_configs.minecraft.server_name} 700 ${config.services.minecraft-servers.user} ${config.services.minecraft-servers.group}"
+      "Z ${service_configs.minecraft.parent_dir}/${service_configs.minecraft.server_name}/squaremap/web 750 ${config.services.minecraft-servers.user} ${config.services.minecraft-servers.group}"
+    ])
   ];
 
   services.minecraft-servers = {
@@ -132,10 +136,8 @@
   };
 
   systemd.tmpfiles.rules = [
-    "Z ${service_configs.minecraft.parent_dir}/${service_configs.minecraft.server_name} 700 ${config.services.minecraft-servers.user} ${config.services.minecraft-servers.group}"
     # Allow caddy (in minecraft group) to traverse to squaremap/web for map.gardling.com
     "z ${service_configs.minecraft.parent_dir}/${service_configs.minecraft.server_name} 710 ${config.services.minecraft-servers.user} ${config.services.minecraft-servers.group}"
     "z ${service_configs.minecraft.parent_dir}/${service_configs.minecraft.server_name}/squaremap 710 ${config.services.minecraft-servers.user} ${config.services.minecraft-servers.group}"
-    "Z ${service_configs.minecraft.parent_dir}/${service_configs.minecraft.server_name}/squaremap/web 750 ${config.services.minecraft-servers.user} ${config.services.minecraft-servers.group}"
   ];
 }

services/monero.nix

@@ -8,6 +8,9 @@
     (lib.serviceMountWithZpool "monero" service_configs.zpool_hdds [
       service_configs.monero.dataDir
     ])
+    (lib.serviceFilePerms "monero" [
+      "Z ${service_configs.monero.dataDir} 0700 monero monero"
+    ])
   ];
 
   services.monero = {
@@ -18,7 +21,4 @@
     };
   };
 
-  systemd.tmpfiles.rules = [
-    "Z ${service_configs.monero.dataDir} 0700 monero monero"
-  ];
 }

services/ntfy.nix

@@ -9,6 +9,9 @@
     (lib.serviceMountWithZpool "ntfy-sh" service_configs.zpool_ssds [
       "/var/lib/private/ntfy-sh"
     ])
+    (lib.serviceFilePerms "ntfy-sh" [
+      "Z /var/lib/private/ntfy-sh 0700 ${config.services.ntfy-sh.user} ${config.services.ntfy-sh.group}"
+    ])
   ];
 
   services.ntfy-sh = {
@@ -28,7 +31,4 @@
     reverse_proxy :${builtins.toString service_configs.ports.ntfy}
   '';
 
-  systemd.tmpfiles.rules = [
-    "Z /var/lib/private/ntfy-sh 0700 ${config.services.ntfy-sh.user} ${config.services.ntfy-sh.group}"
-  ];
 }

services/postgresql.nix

@@ -10,6 +10,9 @@
     (lib.serviceMountWithZpool "postgresql" service_configs.zpool_ssds [
       config.services.postgresql.dataDir
     ])
+    (lib.serviceFilePerms "postgresql" [
+      "Z ${config.services.postgresql.dataDir} 0700 postgres postgres"
+    ])
   ];
 
   services.postgresql = {
@@ -18,8 +21,4 @@
     dataDir = service_configs.postgres.dataDir;
   };
 
-  systemd.tmpfiles.rules = [
-    # postgresql requires 0700
-    "Z ${config.services.postgresql.dataDir} 0700 postgresql postgresql"
-  ];
 }

services/qbittorrent.nix

@@ -17,6 +17,11 @@
       "${config.services.qbittorrent.profileDir}/qBittorrent"
     ])
     (lib.vpnNamespaceOpenPort config.services.qbittorrent.webuiPort "qbittorrent")
+    (lib.serviceFilePerms "qbittorrent" [
+      "Z ${config.services.qbittorrent.serverConfig.Preferences.Downloads.SavePath} 0750 ${config.services.qbittorrent.user} ${service_configs.media_group}"
+      "Z ${config.services.qbittorrent.serverConfig.Preferences.Downloads.TempPath} 0700 ${config.services.qbittorrent.user} ${config.services.qbittorrent.group}"
+      "Z ${config.services.qbittorrent.profileDir} 0700 ${config.services.qbittorrent.user} ${config.services.qbittorrent.group}"
+    ])
   ];
 
   services.qbittorrent = {
@@ -96,12 +101,6 @@
 
   systemd.services.qbittorrent.serviceConfig.TimeoutStopSec = lib.mkForce 10;
 
-  systemd.tmpfiles.rules = [
-    "Z ${config.services.qbittorrent.serverConfig.Preferences.Downloads.SavePath} 0750 ${config.services.qbittorrent.user} ${service_configs.media_group}"
-    "Z ${config.services.qbittorrent.serverConfig.Preferences.Downloads.TempPath} 0700 ${config.services.qbittorrent.user} ${config.services.qbittorrent.group}"
-    "Z ${config.services.qbittorrent.profileDir} 0700 ${config.services.qbittorrent.user} ${config.services.qbittorrent.group}"
-  ];
-
   services.caddy.virtualHosts."torrent.${service_configs.https.domain}".extraConfig = ''
     import ${config.age.secrets.caddy_auth.path}
     reverse_proxy ${config.vpnNamespaces.wg.namespaceAddress}:${builtins.toString config.services.qbittorrent.webuiPort}

services/soulseek.nix

@@ -16,6 +16,12 @@ in
       service_configs.slskd.downloads
       service_configs.slskd.incomplete
     ])
+    (lib.serviceFilePerms "slskd" [
+      "Z ${service_configs.music_dir} 0750 ${username} music"
+      "Z ${service_configs.slskd.base} 0750 ${config.services.slskd.user} ${config.services.slskd.group}"
+      "Z ${service_configs.slskd.downloads} 0750 ${config.services.slskd.user} music"
+      "Z ${service_configs.slskd.incomplete} 0750 ${config.services.slskd.user} music"
+    ])
   ];
 
   users.groups."music" = { };
@@ -65,13 +71,6 @@ in
   users.users.${config.services.jellyfin.user}.extraGroups = [ "music" ];
   users.users.${username}.extraGroups = [ "music" ];
 
-  systemd.tmpfiles.rules = [
-    "Z ${service_configs.music_dir} 0750 ${username} music"
-    "Z ${service_configs.slskd.base} 0750 ${config.services.slskd.user} ${config.services.slskd.group}"
-    "Z ${service_configs.slskd.downloads} 0750 ${config.services.slskd.user} music"
-    "Z ${service_configs.slskd.incomplete} 0750 ${config.services.slskd.user} music"
-  ];
-
   # doesn't work with auth????
   services.caddy.virtualHosts."soulseek.${service_configs.https.domain}".extraConfig = ''
     reverse_proxy :${builtins.toString config.services.slskd.settings.web.port}

services/syncthing.nix

@@ -12,6 +12,11 @@
       service_configs.syncthing.signalBackupDir
       service_configs.syncthing.grayjayBackupDir
     ])
+    (lib.serviceFilePerms "syncthing" [
+      "Z ${service_configs.syncthing.dataDir} 0750 ${config.services.syncthing.user} ${config.services.syncthing.group}"
+      "Z ${service_configs.syncthing.signalBackupDir} 0750 ${config.services.syncthing.user} ${config.services.syncthing.group}"
+      "Z ${service_configs.syncthing.grayjayBackupDir} 0750 ${config.services.syncthing.user} ${config.services.syncthing.group}"
+    ])
   ];
 
   services.syncthing = {
@@ -46,9 +51,4 @@
     reverse_proxy :${toString service_configs.ports.syncthing_gui}
   '';
 
-  systemd.tmpfiles.rules = [
-    "Z ${service_configs.syncthing.dataDir} 0750 ${config.services.syncthing.user} ${config.services.syncthing.group}"
-    "Z ${service_configs.syncthing.signalBackupDir} 0750 ${config.services.syncthing.user} ${config.services.syncthing.group}"
-    "Z ${service_configs.syncthing.grayjayBackupDir} 0750 ${config.services.syncthing.user} ${config.services.syncthing.group}"
-  ];
 }

tests/fail2ban-gitea.nix

@@ -25,6 +25,10 @@ let
         serviceName: zpool: dirs:
         { ... }:
         { };
+      serviceFilePerms =
+        serviceName: tmpfilesRules:
+        { ... }:
+        { };
     }
   );
 

tests/fail2ban-immich.nix

@@ -24,6 +24,10 @@ let
         serviceName: zpool: dirs:
         { ... }:
         { };
+      serviceFilePerms =
+        serviceName: tmpfilesRules:
+        { ... }:
+        { };
     }
   );
 

tests/fail2ban-jellyfin.nix

@@ -26,6 +26,10 @@ let
         serviceName: zpool: dirs:
         { ... }:
         { };
+      serviceFilePerms =
+        serviceName: tmpfilesRules:
+        { ... }:
+        { };
       optimizePackage = pkg: pkg; # No-op for testing
     }
   );

tests/fail2ban-vaultwarden.nix

@@ -24,6 +24,10 @@ let
         serviceName: zpool: dirs:
         { ... }:
         { };
+      serviceFilePerms =
+        serviceName: tmpfilesRules:
+        { ... }:
+        { };
     }
   );
 

tests/file-perms.nix

@@ -0,0 +1,53 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  testPkgs = pkgs.appendOverlays [ (import ../modules/overlays.nix) ];
+in
+testPkgs.testers.runNixOSTest {
+  name = "file-perms test";
+
+  nodes.machine =
+    { pkgs, ... }:
+    {
+      imports = [
+        (lib.serviceFilePerms "test-service" [
+          "Z /tmp/test-perms-dir 0750 nobody nogroup"
+        ])
+      ];
+
+      systemd.services."test-service" = {
+        serviceConfig = {
+          Type = "oneshot";
+          RemainAfterExit = true;
+          ExecStart = lib.getExe pkgs.bash;
+        };
+      };
+    };
+
+  testScript = ''
+    start_all()
+    machine.wait_for_unit("multi-user.target")
+
+    # Create test directory with wrong permissions
+    machine.succeed("mkdir -p /tmp/test-perms-dir")
+    machine.succeed("chown root:root /tmp/test-perms-dir")
+    machine.succeed("chmod 700 /tmp/test-perms-dir")
+
+    # Start service -- this should pull in test-service-file-perms
+    machine.succeed("systemctl start test-service")
+
+    # Verify file-perms service ran and is active
+    machine.succeed("systemctl is-active test-service-file-perms.service")
+
+    # Verify permissions were fixed by tmpfiles
+    result = machine.succeed("stat -c '%U:%G' /tmp/test-perms-dir").strip()
+    assert result == "nobody:nogroup", f"Expected nobody:nogroup, got {result}"
+
+    result = machine.succeed("stat -c '%a' /tmp/test-perms-dir").strip()
+    assert result == "750", f"Expected 750, got {result}"
+  '';
+}

tests/tests.nix

@@ -12,6 +12,7 @@ in
   testTest = handleTest ./testTest.nix;
   minecraftTest = handleTest ./minecraft.nix;
   jellyfinQbittorrentMonitorTest = handleTest ./jellyfin-qbittorrent-monitor.nix;
+  filePermsTest = handleTest ./file-perms.nix;
 
   # fail2ban tests
   fail2banSshTest = handleTest ./fail2ban-ssh.nix;