From d7535dd0430584ec9ce113f556f3bc97da48a4b5 Mon Sep 17 00:00:00 2001
From: rnhmjoj <rnhmjoj@inventati.org>
Date: Wed, 20 Aug 2025 18:56:24 +0200
Subject: [PATCH] nixos/networkmanager: fix for rootless wpa_supplicant

---
 .../services/networking/networkmanager.nix    | 19 ++++++++++++-------
 .../services/networking/wpa_supplicant.nix    | 19 +++++++++++++------
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/nixos/modules/services/networking/networkmanager.nix b/nixos/modules/services/networking/networkmanager.nix
index 9295157b793b..f76e649d75e9 100644
--- a/nixos/modules/services/networking/networkmanager.nix
+++ b/nixos/modules/services/networking/networkmanager.nix
@@ -11,7 +11,8 @@ let
   cfg = config.networking.networkmanager;
   ini = pkgs.formats.ini { };
 
-  delegateWireless = config.networking.wireless.enable == true && cfg.unmanaged != [ ];
+  # Whether wpa_supplicant is managed independently
+  delegateWireless = config.networking.wireless.networks != { } && cfg.unmanaged != [ ];
 
   enableIwd = cfg.wifi.backend == "iwd";
 
@@ -136,10 +137,7 @@ let
     cfg.package
   ]
   ++ cfg.plugins
-  ++ pluginRuntimeDeps
-  ++ lib.optionals (!delegateWireless && !enableIwd) [
-    pkgs.wpa_supplicant
-  ];
+  ++ pluginRuntimeDeps;
 in
 {
 
@@ -541,9 +539,9 @@ in
 
     assertions = [
       {
-        assertion = config.networking.wireless.enable == true -> cfg.unmanaged != [ ];
+        assertion = config.networking.wireless.networks != { } -> cfg.unmanaged != [ ];
         message = ''
-          You can not use networking.networkmanager with networking.wireless.
+          You can not use networking.networkmanager with networking.wireless.networks.
           Except if you mark some interfaces as <literal>unmanaged</literal> by NetworkManager.
         '';
       }
@@ -676,6 +674,13 @@ in
         useDHCP = false;
       })
 
+      (mkIf (!delegateWireless && !enableIwd) {
+        # Enable wpa_supplicant but fully control it over DBus
+        wireless.enable = true;
+        wireless.autoDetectInterfaces = false;
+        wireless.dbusControlled = true;
+      })
+
       (mkIf enableIwd {
         wireless.iwd.enable = true;
       })
diff --git a/nixos/modules/services/networking/wpa_supplicant.nix b/nixos/modules/services/networking/wpa_supplicant.nix
index 8fa11f9ef87e..124bd9c9eda0 100644
--- a/nixos/modules/services/networking/wpa_supplicant.nix
+++ b/nixos/modules/services/networking/wpa_supplicant.nix
@@ -199,7 +199,12 @@ let
       script = ''
         iface_args="-s ${optionalString cfg.dbusControlled "-u"} -D${cfg.driver} ${configStr}"
         ${
-          if iface == null then
+          if iface != null then
+            ''
+              # add known interface to the daemon arguments
+              args="-i${iface} $iface_args"
+            ''
+          else if cfg.autoDetectInterfaces then
             ''
               # detect interfaces automatically
 
@@ -222,10 +227,7 @@ let
               done
             ''
           else
-            ''
-              # add known interface to the daemon arguments
-              args="-i${iface} $iface_args"
-            ''
+            "args=$iface_args"
         }
 
         # finally start daemon
@@ -251,7 +253,8 @@ in
           "wlan1"
         ];
         description = ''
-          The interfaces {command}`wpa_supplicant` will use. If empty, it will
+          The interfaces {command}`wpa_supplicant` will use. If empty and
+          [](#opt-networking.wireless.autoDetectInterfaces) is true it will
           automatically use all wireless interfaces.
 
           ::: {.note}
@@ -260,6 +263,10 @@ in
         '';
       };
 
+      autoDetectInterfaces = mkEnableOption "automatic detection of wireless interfaces" // {
+        default = true;
+      };
+
       driver = mkOption {
         type = types.str;
         default = "nl80211,wext";