nixos: explicitely set security.wrappers ownership

This is slightly more verbose and inconvenient, but it forces you
to think about what the wrapper ownership and permissions will be.

nixos/modules/programs/bandwhich.nix

···
   config = mkIf cfg.enable {
     environment.systemPackages = with pkgs; [ bandwhich ];
     security.wrappers.bandwhich = {
-      source = "${pkgs.bandwhich}/bin/bandwhich";
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_raw,cap_net_admin+ep";
+      source = "${pkgs.bandwhich}/bin/bandwhich";
     };
   };
 }

nixos/modules/programs/captive-browser.nix

···
       );
 
     security.wrappers.udhcpc = {
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_raw+p";
       source = "${pkgs.busybox}/bin/udhcpc";
     };
 
     security.wrappers.captive-browser = {
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_raw+p";
       source = pkgs.writeShellScript "captive-browser" ''
         export PREV_CONFIG_HOME="$XDG_CONFIG_HOME"

nixos/modules/programs/firejail.nix

···
   };
 
   config = mkIf cfg.enable {
-    security.wrappers.firejail.source = "${lib.getBin pkgs.firejail}/bin/firejail";
+    security.wrappers.firejail =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${lib.getBin pkgs.firejail}/bin/firejail";
+      };
 
     environment.systemPackages = [ pkgs.firejail ] ++ [ wrappedBins ];
   };

nixos/modules/programs/gamemode.nix

···
       polkit.enable = true;
       wrappers = mkIf cfg.enableRenice {
         gamemoded = {
+          owner = "root";
+          group = "root";
           source = "${pkgs.gamemode}/bin/gamemoded";
           capabilities = "cap_sys_nice+ep";
         };

nixos/modules/programs/iftop.nix

···
   config = mkIf cfg.enable {
     environment.systemPackages = [ pkgs.iftop ];
     security.wrappers.iftop = {
-      source = "${pkgs.iftop}/bin/iftop";
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_raw+p";
+      source = "${pkgs.iftop}/bin/iftop";
     };
   };
 }

nixos/modules/programs/iotop.nix

···
   };
   config = mkIf cfg.enable {
     security.wrappers.iotop = {
-      source = "${pkgs.iotop}/bin/iotop";
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_admin+p";
+      source = "${pkgs.iotop}/bin/iotop";
     };
   };
 }

nixos/modules/programs/kbdlight.nix

···
 
   config = mkIf cfg.enable {
     environment.systemPackages = [ pkgs.kbdlight ];
-    security.wrappers.kbdlight.source = "${pkgs.kbdlight.out}/bin/kbdlight";
+    security.wrappers.kbdlight =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${pkgs.kbdlight.out}/bin/kbdlight";
+      };
   };
 }

nixos/modules/programs/liboping.nix

···
     security.wrappers = mkMerge (map (
       exec: {
         "${exec}" = {
-          source = "${pkgs.liboping}/bin/${exec}";
+          owner = "root";
+          group = "root";
           capabilities = "cap_net_raw+p";
+          source = "${pkgs.liboping}/bin/${exec}";
         };
       }
     ) [ "oping" "noping" ]);

nixos/modules/programs/mtr.nix

···
     environment.systemPackages = with pkgs; [ cfg.package ];
 
     security.wrappers.mtr-packet = {
-      source = "${cfg.package}/bin/mtr-packet";
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_raw+p";
+      source = "${cfg.package}/bin/mtr-packet";
     };
   };
 }

nixos/modules/programs/noisetorch.nix

···
 
   config = mkIf cfg.enable {
     security.wrappers.noisetorch = {
-      source = "${cfg.package}/bin/noisetorch";
+      owner = "root";
+      group = "root";
       capabilities = "cap_sys_resource=+ep";
+      source = "${cfg.package}/bin/noisetorch";
     };
   };
 }

nixos/modules/programs/shadow.nix

···
 
     '';
 
+  mkSetuidRoot = source:
+    { setuid = true;
+      owner = "root";
+      group = "root";
+      inherit source;
+    };
+
 in
 
 {
···
       };
 
     security.wrappers = {
-      su.source        = "${pkgs.shadow.su}/bin/su";
-      sg.source        = "${pkgs.shadow.out}/bin/sg";
-      newgrp.source    = "${pkgs.shadow.out}/bin/newgrp";
-      newuidmap.source = "${pkgs.shadow.out}/bin/newuidmap";
-      newgidmap.source = "${pkgs.shadow.out}/bin/newgidmap";
+      su        = mkSetuidRoot "${pkgs.shadow.su}/bin/su";
+      sg        = mkSetuidRoot "${pkgs.shadow.out}/bin/sg";
+      newgrp    = mkSetuidRoot "${pkgs.shadow.out}/bin/newgrp";
+      newuidmap = mkSetuidRoot "${pkgs.shadow.out}/bin/newuidmap";
+      newgidmap = mkSetuidRoot "${pkgs.shadow.out}/bin/newgidmap";
     } // lib.optionalAttrs config.users.mutableUsers {
-      chsh.source      = "${pkgs.shadow.out}/bin/chsh";
-      passwd.source    = "${pkgs.shadow.out}/bin/passwd";
+      chsh   = mkSetuidRoot "${pkgs.shadow.out}/bin/chsh";
+      passwd = mkSetuidRoot "${pkgs.shadow.out}/bin/passwd";
     };
   };
 }

nixos/modules/programs/singularity.nix

···
 
   config = mkIf cfg.enable {
       environment.systemPackages = [ singularity ];
-      security.wrappers.singularity-suid.source = "${singularity}/libexec/singularity/bin/starter-suid.orig";
+      security.wrappers.singularity-suid =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${singularity}/libexec/singularity/bin/starter-suid.orig";
+      };
       systemd.tmpfiles.rules = [
         "d /var/singularity/mnt/session 0770 root root -"
         "d /var/singularity/mnt/final 0770 root root -"

nixos/modules/programs/slock.nix

···
 
   config = mkIf cfg.enable {
     environment.systemPackages = [ pkgs.slock ];
-    security.wrappers.slock.source = "${pkgs.slock.out}/bin/slock";
+    security.wrappers.slock =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${pkgs.slock.out}/bin/slock";
+      };
   };
 }

nixos/modules/programs/traceroute.nix

···
 
   config = mkIf cfg.enable {
     security.wrappers.traceroute = {
-      source = "${pkgs.traceroute}/bin/traceroute";
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_raw+p";
+      source = "${pkgs.traceroute}/bin/traceroute";
     };
   };
 }

nixos/modules/programs/udevil.nix

···
   options.programs.udevil.enable = mkEnableOption "udevil";
 
   config = mkIf cfg.enable {
-    security.wrappers.udevil.source = "${lib.getBin pkgs.udevil}/bin/udevil";
+    security.wrappers.udevil =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${lib.getBin pkgs.udevil}/bin/udevil";
+      };
   };
 }

nixos/modules/programs/wavemon.nix

···
   config = mkIf cfg.enable {
     environment.systemPackages = with pkgs; [ wavemon ];
     security.wrappers.wavemon = {
-      source = "${pkgs.wavemon}/bin/wavemon";
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_admin+ep";
+      source = "${pkgs.wavemon}/bin/wavemon";
     };
   };
 }

nixos/modules/programs/wshowkeys.nix

···
   };
 
   config = mkIf cfg.enable {
-    security.wrappers.wshowkeys.source = "${pkgs.wshowkeys}/bin/wshowkeys";
+    security.wrappers.wshowkeys =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${pkgs.wshowkeys}/bin/wshowkeys";
+      };
   };
 }

nixos/modules/security/chromium-suid-sandbox.nix

···
 
   config = mkIf cfg.enable {
     environment.systemPackages = [ sandbox ];
-    security.wrappers.${sandbox.passthru.sandboxExecutableName}.source = "${sandbox}/bin/${sandbox.passthru.sandboxExecutableName}";
+    security.wrappers.${sandbox.passthru.sandboxExecutableName} =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${sandbox}/bin/${sandbox.passthru.sandboxExecutableName}";
+      };
   };
 }

nixos/modules/security/doas.nix

···
       }
     ];
 
-    security.wrappers = {
-      doas.source = "${doas}/bin/doas";
-    };
+    security.wrappers.doas =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${doas}/bin/doas";
+      };
 
     environment.systemPackages = [
       doas

nixos/modules/security/duosec.nix

···
   config = mkIf (cfg.ssh.enable || cfg.pam.enable) {
     environment.systemPackages = [ pkgs.duo-unix ];
 
-    security.wrappers.login_duo.source = "${pkgs.duo-unix.out}/bin/login_duo";
+    security.wrappers.login_duo =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${pkgs.duo-unix.out}/bin/login_duo";
+      };
 
     system.activationScripts = {
       login_duo = mkIf cfg.ssh.enable ''

nixos/modules/security/pam_usb.nix

···
 
     # Make sure pmount and pumount are setuid wrapped.
     security.wrappers = {
-      pmount.source = "${pkgs.pmount.out}/bin/pmount";
-      pumount.source = "${pkgs.pmount.out}/bin/pumount";
+      pmount =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.pmount.out}/bin/pmount";
+        };
+      pumount =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.pmount.out}/bin/pumount";
+        };
     };
 
     environment.systemPackages = [ pkgs.pmount ];

nixos/modules/security/polkit.nix

···
     security.pam.services.polkit-1 = {};
 
     security.wrappers = {
-      pkexec.source = "${pkgs.polkit.bin}/bin/pkexec";
-      polkit-agent-helper-1.source = "${pkgs.polkit.out}/lib/polkit-1/polkit-agent-helper-1";
+      pkexec =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.polkit.bin}/bin/pkexec";
+        };
+      polkit-agent-helper-1 =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.polkit.out}/lib/polkit-1/polkit-agent-helper-1";
+        };
     };
 
     systemd.tmpfiles.rules = [

nixos/modules/security/wrappers/default.nix

···
       };
     options.owner = lib.mkOption
       { type = lib.types.str;
-        default = "root";
         description = "The owner of the wrapper program.";
       };
     options.group = lib.mkOption
       { type = lib.types.str;
-        default = "root";
         description = "The group of the wrapper program.";
       };
     options.permissions = lib.mkOption
···
       };
     options.setuid = lib.mkOption
       { type = lib.types.bool;
-        default = true;
+        default = false;
         description = "Whether to add the setuid bit the wrapper program.";
       };
     options.setgid = lib.mkOption
···
       default = {};
       example = lib.literalExample
         ''
-          { sendmail.source = "/nix/store/.../bin/sendmail";
-            ping = {
-              source  = "${pkgs.iputils.out}/bin/ping";
-              owner   = "nobody";
-              group   = "nogroup";
-              capabilities = "cap_net_raw+ep";
-            };
+          {
+            # a setuid root program
+            doas =
+              { setuid = true;
+                owner = "root";
+                group = "root";
+                source = "''${pkgs.doas}/bin/doas";
+              };
+
+            # a setgid program
+            locate =
+              { setgid = true;
+                owner = "root";
+                group = "mlocate";
+                source = "''${pkgs.locate}/bin/locate";
+              };
+
+            # a program with the CAP_NET_RAW capability
+            ping =
+              { owner = "root";
+                group = "root";
+                capabilities = "cap_net_raw+ep";
+                source = "''${pkgs.iputils.out}/bin/ping";
+              };
           }
         '';
       description = ''
···
         }
       ) wrappers;
 
-    security.wrappers = {
-      # These are mount related wrappers that require the +s permission.
-      fusermount.source = "${pkgs.fuse}/bin/fusermount";
-      fusermount3.source = "${pkgs.fuse3}/bin/fusermount3";
-      mount.source = "${lib.getBin pkgs.util-linux}/bin/mount";
-      umount.source = "${lib.getBin pkgs.util-linux}/bin/umount";
-    };
+    security.wrappers =
+      let
+        mkSetuidRoot = source:
+          { setuid = true;
+            owner = "root";
+            group = "root";
+            inherit source;
+          };
+      in
+      { # These are mount related wrappers that require the +s permission.
+        fusermount  = mkSetuidRoot "${pkgs.fuse}/bin/fusermount";
+        fusermount3 = mkSetuidRoot "${pkgs.fuse3}/bin/fusermount3";
+        mount  = mkSetuidRoot "${lib.getBin pkgs.util-linux}/bin/mount";
+        umount = mkSetuidRoot "${lib.getBin pkgs.util-linux}/bin/umount";
+      };
 
     boot.specialFileSystems.${parentWrapperDir} = {
       fsType = "tmpfs";

nixos/modules/services/desktops/gnome/gnome-keyring.nix

···
     security.pam.services.login.enableGnomeKeyring = true;
 
     security.wrappers.gnome-keyring-daemon = {
-      source = "${pkgs.gnome.gnome-keyring}/bin/gnome-keyring-daemon";
+      owner = "root";
+      group = "root";
       capabilities = "cap_ipc_lock=ep";
+      source = "${pkgs.gnome.gnome-keyring}/bin/gnome-keyring-daemon";
     };
 
   };

nixos/modules/services/mail/exim.nix

···
       gid = config.ids.gids.exim;
     };
 
-    security.wrappers.exim.source = "${cfg.package}/bin/exim";
+    security.wrappers.exim =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${cfg.package}/bin/exim";
+      };
 
     systemd.services.exim = {
       description = "Exim Mail Daemon";

nixos/modules/services/misc/mame.nix

···
     environment.systemPackages = [ pkgs.mame ];
 
     security.wrappers."${mame}" = {
-      source = "${pkgs.mame}/bin/${mame}";
+      owner = "root";
+      group = "root";
       capabilities = "cap_net_admin,cap_net_raw+eip";
+      source = "${pkgs.mame}/bin/${mame}";
     };
 
     systemd.services.mame = {

nixos/modules/services/misc/weechat.nix

···
       wants = [ "network.target" ];
     };
 
-    security.wrappers.screen.source = "${pkgs.screen}/bin/screen";
+    security.wrappers.screen =
+      { setuid = true;
+        owner = "root";
+        group = "root";
+        source = "${pkgs.screen}/bin/screen";
+      };
   };
 
   meta.doc = ./weechat.xml;

nixos/modules/services/monitoring/incron.nix

···
 
     environment.systemPackages = [ pkgs.incron ];
 
-    security.wrappers.incrontab.source = "${pkgs.incron}/bin/incrontab";
+    security.wrappers.incrontab =
+    { setuid = true;
+      owner = "root";
+      group = "root";
+      source = "${pkgs.incron}/bin/incrontab";
+    };
 
     # incron won't read symlinks
     environment.etc."incron.d/system" = {

nixos/modules/services/monitoring/zabbix-proxy.nix

···
     };
 
     security.wrappers = {
-      fping.source = "${pkgs.fping}/bin/fping";
+      fping =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.fping}/bin/fping";
+        };
     };
 
     systemd.services.zabbix-proxy = {

nixos/modules/services/networking/smokeping.nix

···
       }
     ];
     security.wrappers = {
-      fping.source = "${pkgs.fping}/bin/fping";
-      fping6.source = "${pkgs.fping}/bin/fping6";
+      fping =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.fping}/bin/fping";
+        };
+      fping6 =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.fping}/bin/fping6";
+        };
     };
     environment.systemPackages = [ pkgs.fping ];
     users.users.${cfg.user} = {

nixos/modules/services/scheduling/cron.nix

···
 
     { services.cron.enable = mkDefault (allFiles != []); }
     (mkIf (config.services.cron.enable) {
-      security.wrappers.crontab.source = "${cronNixosPkg}/bin/crontab";
+      security.wrappers.crontab =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${cronNixosPkg}/bin/crontab";
+        };
       environment.systemPackages = [ cronNixosPkg ];
       environment.etc.crontab =
         { source = pkgs.runCommand "crontabs" { inherit allFiles; preferLocalBuild = true; }

nixos/modules/services/scheduling/fcron.nix

···
         source = "${pkgs.fcron}/bin/fcronsighup";
         owner = "root";
         group = "fcron";
+        setuid = true;
       };
     };
     systemd.services.fcron = {

nixos/modules/services/video/replay-sorcery.nix

···
 
     security.wrappers = mkIf cfg.enableSysAdminCapability {
       replay-sorcery = {
-        source = "${pkgs.replay-sorcery}/bin/replay-sorcery";
+        owner = "root";
+        group = "root";
         capabilities = "cap_sys_admin+ep";
+        source = "${pkgs.replay-sorcery}/bin/replay-sorcery";
       };
     };
 

nixos/modules/services/x11/desktop-managers/enlightenment.nix

···
 
     # Wrappers for programs installed by enlightenment that should be setuid
     security.wrappers = {
-      enlightenment_ckpasswd.source = "${pkgs.enlightenment.enlightenment}/lib/enlightenment/utils/enlightenment_ckpasswd";
-      enlightenment_sys.source = "${pkgs.enlightenment.enlightenment}/lib/enlightenment/utils/enlightenment_sys";
-      enlightenment_system.source = "${pkgs.enlightenment.enlightenment}/lib/enlightenment/utils/enlightenment_system";
+      enlightenment_ckpasswd =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.enlightenment.enlightenment}/lib/enlightenment/utils/enlightenment_ckpasswd";
+        };
+      enlightenment_sys =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.enlightenment.enlightenment}/lib/enlightenment/utils/enlightenment_sys";
+        };
+      enlightenment_system =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.enlightenment.enlightenment}/lib/enlightenment/utils/enlightenment_system";
+        };
     };
 
     environment.etc."X11/xkb".source = xcfg.xkbDir;

nixos/modules/services/x11/desktop-managers/plasma5.nix

···
       };
 
       security.wrappers = {
-        kcheckpass.source = "${lib.getBin libsForQt5.kscreenlocker}/libexec/kcheckpass";
-        start_kdeinit.source = "${lib.getBin libsForQt5.kinit}/libexec/kf5/start_kdeinit";
-        kwin_wayland = {
-          source = "${lib.getBin plasma5.kwin}/bin/kwin_wayland";
-          capabilities = "cap_sys_nice+ep";
-        };
+        kcheckpass =
+          { setuid = true;
+            owner = "root";
+            group = "root";
+            source = "${lib.getBin libsForQt5.kscreenlocker}/libexec/kcheckpass";
+          };
+        start_kdeinit =
+          { setuid = true;
+            owner = "root";
+            group = "root";
+            source = "${lib.getBin libsForQt5.kinit}/libexec/kf5/start_kdeinit";
+          };
+        kwin_wayland =
+          { owner = "root";
+            group = "root";
+            capabilities = "cap_sys_nice+ep";
+            source = "${lib.getBin plasma5.kwin}/bin/kwin_wayland";
+          };
       };
 
       # DDC support

nixos/modules/tasks/filesystems/ecryptfs.nix

···
   config = mkIf (any (fs: fs == "ecryptfs") config.boot.supportedFilesystems) {
     system.fsPackages = [ pkgs.ecryptfs ];
     security.wrappers = {
-      "mount.ecryptfs_private".source = "${pkgs.ecryptfs.out}/bin/mount.ecryptfs_private";
-      "umount.ecryptfs_private".source = "${pkgs.ecryptfs.out}/bin/umount.ecryptfs_private";
+      "mount.ecryptfs_private" =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.ecryptfs.out}/bin/mount.ecryptfs_private";
+        };
+      "umount.ecryptfs_private" =
+        { setuid = true;
+          owner = "root";
+          group = "root";
+          source = "${pkgs.ecryptfs.out}/bin/umount.ecryptfs_private";
+        };
     };
   };
 }

nixos/modules/tasks/network-interfaces.nix

···
     # kernel because we need the ambient capability
     security.wrappers = if (versionAtLeast (getVersion config.boot.kernelPackages.kernel) "4.3") then {
       ping = {
-        source  = "${pkgs.iputils.out}/bin/ping";
+        owner = "root";
+        group = "root";
         capabilities = "cap_net_raw+p";
+        source = "${pkgs.iputils.out}/bin/ping";
       };
     } else {
-      ping.source = "${pkgs.iputils.out}/bin/ping";
+      setuid = true;
+      owner = "root";
+      group = "root";
+      source = "${pkgs.iputils.out}/bin/ping";
     };
     security.apparmor.policies."bin.ping".profile = lib.mkIf config.security.apparmor.policies."bin.ping".enable (lib.mkAfter ''
       /run/wrappers/bin/ping {

nixos/modules/virtualisation/libvirtd.nix

···
     };
 
     security.wrappers.qemu-bridge-helper = {
+      setuid = true;
+      owner = "root";
+      group = "root";
       source = "/run/${dirName}/nix-helpers/qemu-bridge-helper";
     };
 

nixos/modules/virtualisation/spice-usb-redirection.nix

···
 
   config = lib.mkIf config.virtualisation.spiceUSBRedirection.enable {
     environment.systemPackages = [ pkgs.spice-gtk ]; # For polkit actions
-    security.wrappers.spice-client-glib-usb-acl-helper ={
-      source = "${pkgs.spice-gtk}/bin/spice-client-glib-usb-acl-helper";
+    security.wrappers.spice-client-glib-usb-acl-helper = {
+      owner = "root";
+      group = "root";
       capabilities = "cap_fowner+ep";
+      source = "${pkgs.spice-gtk}/bin/spice-client-glib-usb-acl-helper";
     };
   };