From 7ba690add6ca095f20c3f11ec25a2664a4b7219e Mon Sep 17 00:00:00 2001
From: Mathijs Kwik <mathijs@bluescreen303.nl>
Date: Sun, 1 Apr 2012 10:54:10 +0000
Subject: [PATCH] optionally allow normal users to control wpa_supplicant
 through wpa_gui or wpa_cli.

Comes with a default wpa_supplicant.conf, which gets updated through
aforementioned utilities.

svn path=/nixos/trunk/; revision=33510
---
 .../services/networking/wpa_supplicant.nix    | 98 +++++++++++++------
 1 file changed, 68 insertions(+), 30 deletions(-)

diff --git a/modules/services/networking/wpa_supplicant.nix b/modules/services/networking/wpa_supplicant.nix
index d2b57fb97d54..338a801f701f 100644
--- a/modules/services/networking/wpa_supplicant.nix
+++ b/modules/services/networking/wpa_supplicant.nix
@@ -4,10 +4,11 @@ with pkgs.lib;
 
 let
 
+  cfg = config.networking.wireless;
   configFile = "/etc/wpa_supplicant.conf";
 
   ifaces =
-    config.networking.wireless.interfaces ++
+    cfg.interfaces ++
     optional (config.networking.WLANInterface != "") config.networking.WLANInterface;
 
 in
@@ -18,40 +19,69 @@ in
 
   options = {
   
-    networking.wireless.enable = mkOption {
-      default = false;
-      description = ''
-        Whether to start <command>wpa_supplicant</command> to scan for
-        and associate with wireless networks.  Note: NixOS currently
-        does not generate <command>wpa_supplicant</command>'s
-        configuration file, <filename>${configFile}</filename>.  You
-        should edit this file yourself to define wireless networks,
-        WPA keys and so on (see
-        <citerefentry><refentrytitle>wpa_supplicant.conf</refentrytitle>
-        <manvolnum>5</manvolnum></citerefentry>).
-      '';
-    };
-
     networking.WLANInterface = mkOption {
       default = "";
       description = "Obsolete. Use <option>networking.wireless.interfaces</option> instead.";
     };
 
-    networking.wireless.interfaces = mkOption {
-      default = [];
-      example = [ "wlan0" "wlan1" ];
-      description = ''
-        The interfaces <command>wpa_supplicant</command> will use.  If empty, it will
-        automatically use all wireless interfaces.
-      '';
-    };
+    networking.wireless = {
+      enable = mkOption {
+        default = false;
+        description = ''
+          Whether to start <command>wpa_supplicant</command> to scan for
+          and associate with wireless networks.  Note: NixOS currently
+          does not generate <command>wpa_supplicant</command>'s
+          configuration file, <filename>${configFile}</filename>.  You
+          should edit this file yourself to define wireless networks,
+          WPA keys and so on (see
+          <citerefentry><refentrytitle>wpa_supplicant.conf</refentrytitle>
+          <manvolnum>5</manvolnum></citerefentry>).
+        '';
+      };
 
+      interfaces = mkOption {
+        default = [];
+        example = [ "wlan0" "wlan1" ];
+        description = ''
+          The interfaces <command>wpa_supplicant</command> will use.  If empty, it will
+          automatically use all wireless interfaces.
+        '';
+      };
+
+      driver = mkOption {
+        default = "";
+        example = "nl80211";
+        description = "force a specific wpa_supplicant driver";
+      };
+
+      userControlled = {
+        enable = mkOption {
+          default = false;
+          description = ''
+            Allow normal users to control wpa_supplicant through wpa_gui or wpa_cli.
+            This is useful for laptop users that switch networks a lot.
+
+            When you want to use this, make sure ${configFile} doesn't exist.
+            It will be created for you.
+
+            Currently it is also necesarry to explicitly specify networking.wireless.interfaces
+          '';
+        };
+
+        group = mkOption {
+          default = "wheel";
+          example = "network";
+          type = types.string;
+          description = "members of this group can control wpa_supplicant";
+        };
+      };
+    };
   };
 
 
   ###### implementation
   
-  config = mkIf config.networking.wireless.enable {
+  config = mkIf cfg.enable {
 
     environment.systemPackages =  [ pkgs.wpa_supplicant ];
 
@@ -63,11 +93,15 @@ in
 
         path = [ pkgs.wpa_supplicant ];
 
-        preStart =
-          ''
-            touch -a ${configFile}
-            chmod 600 ${configFile}
-          '';
+        preStart = ''
+          touch -a ${configFile}
+          chmod 600 ${configFile}
+        '' + optionalString cfg.userControlled.enable ''
+          if [ ! -s ${configFile} ]; then
+            echo "ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=${cfg.userControlled.group}" >> ${configFile}
+            echo "update_config=1" >> ${configFile}
+          fi
+        '';
 
         script =
           ''
@@ -80,7 +114,7 @@ in
             '' else ''
               ifaces="${concatStringsSep " -N " (map (i: "-i${i}") ifaces)}"
             ''}
-            exec wpa_supplicant -s -u -c ${configFile} $ifaces
+            exec wpa_supplicant -s -u ${optionalString (cfg.driver != "") "-D${cfg.driver}"} -c ${configFile} $ifaces
           '';
       };
   
@@ -89,6 +123,10 @@ in
         ${config.system.build.upstart}/sbin/restart wpa_supplicant
       '';
 
+    assertions = [{ assertion = !cfg.userControlled.enable || cfg.interfaces != []; 
+                    message = "user controlled wpa_supplicant needs explicit networking.wireless.interfaces";}];
+
+
   };
 
 }