schema: Add setting allowing to use SDES

Key exchanges in SDES can only be done securely with TLS and the option
is disabled by default if not using TLS as the transport protocol.

This setting allows to override this behaviour if the user desires
it (f.e. if the user considers the network his packets go through to be trusted).

data/org.gnome.Calls.gschema.xml

@@ -26,5 +26,11 @@
       <description>The preferred audio codecs to use for VoIP calls (if available)</description>
     </key>
 
+    <key name="always-allow-sdes" type="b">
+      <default>false</default>
+      <summary>Whether to allow using SDES for SRTP without TLS as the transport</summary>
+      <description>Set to true if you want to allow with keys exchanged in cleartext.</description>
+    </key>
+
   </schema>
 </schemalist>

src/calls-settings.c

@@ -42,6 +42,7 @@ enum {
   PROP_COUNTRY_CODE,
   PROP_AUTOLOAD_PLUGINS,
   PROP_PREFERRED_AUDIO_CODECS,
+  PROP_ALWAYS_ALLOW_SDES,
   PROP_LAST_PROP
 };
 static GParamSpec *props[PROP_LAST_PROP];
@@ -53,6 +54,7 @@ struct _CallsSettings {
 
   GStrv      autoload_plugins;
   GStrv      preferred_audio_codecs;
+  gboolean   always_allow_sdes;
 };
 
 G_DEFINE_TYPE (CallsSettings, calls_settings, G_TYPE_OBJECT)
@@ -83,6 +85,10 @@ calls_settings_set_property (GObject      *object,
     calls_settings_set_preferred_audio_codecs (self, g_value_get_boxed (value));
     break;
 
+  case PROP_ALWAYS_ALLOW_SDES:
+    calls_settings_set_always_allow_sdes (self, g_value_get_boolean (value));
+    break;
+
   default:
     G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     break;
@@ -115,6 +121,10 @@ calls_settings_get_property (GObject    *object,
     g_value_take_boxed (value, calls_settings_get_preferred_audio_codecs (self));
     break;
 
+  case PROP_ALWAYS_ALLOW_SDES:
+    g_value_set_boolean (value, calls_settings_get_always_allow_sdes (self));
+    break;
+
   default:
     G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     break;
@@ -141,6 +151,8 @@ calls_settings_constructed (GObject *object)
                    self, "autoload-plugins", G_SETTINGS_BIND_DEFAULT);
   g_settings_bind (self->settings, "preferred-audio-codecs",
                    self, "preferred-audio-codecs", G_SETTINGS_BIND_DEFAULT);
+  g_settings_bind (self->settings, "always-allow-sdes",
+                   self, "always-allow-sdes", G_SETTINGS_BIND_DEFAULT);
 }
 
 
@@ -171,6 +183,7 @@ calls_settings_class_init (CallsSettingsClass *klass)
                           "Automatically use default origins",
                           TRUE,
                           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
   props[PROP_COUNTRY_CODE] =
     g_param_spec_string ("country-code",
                          "country code",
@@ -192,6 +205,13 @@ calls_settings_class_init (CallsSettingsClass *klass)
                         G_TYPE_STRV,
                         G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
 
+  props[PROP_ALWAYS_ALLOW_SDES] =
+    g_param_spec_boolean ("always-allow-sdes",
+                          "Always allow SDES",
+                          "Whether to always allow using key exchange (without TLS)",
+                          FALSE,
+                          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
   g_object_class_install_properties (object_class, PROP_LAST_PROP, props);
 }
 
@@ -212,9 +232,9 @@ calls_settings_get_default (void)
   static CallsSettings *instance = NULL;
 
   if (!instance) {
-      instance = g_object_new (CALLS_TYPE_SETTINGS, NULL);
+    instance = g_object_new (CALLS_TYPE_SETTINGS, NULL);
-      g_object_add_weak_pointer (G_OBJECT (instance), (gpointer *)&instance);
+    g_object_add_weak_pointer (G_OBJECT (instance), (gpointer *) &instance);
-    }
+  }
 
   return instance;
 }
@@ -374,3 +394,27 @@ calls_settings_set_preferred_audio_codecs (CallsSettings      *self,
   if (!initial)
     g_object_notify_by_pspec (G_OBJECT (self), props[PROP_PREFERRED_AUDIO_CODECS]);
 }
+
+
+gboolean
+calls_settings_get_always_allow_sdes (CallsSettings *self)
+{
+  g_return_val_if_fail (CALLS_IS_SETTINGS (self), FALSE);
+
+  return self->always_allow_sdes;
+}
+
+
+void
+calls_settings_set_always_allow_sdes (CallsSettings *self,
+                                      gboolean       allowed)
+{
+  g_return_if_fail (CALLS_IS_SETTINGS (self));
+
+  if (self->always_allow_sdes == allowed)
+    return;
+
+  self->always_allow_sdes = allowed;
+
+  g_object_notify_by_pspec (G_OBJECT (self), props[PROP_ALWAYS_ALLOW_SDES]);
+}

src/calls-settings.h

@@ -45,5 +45,8 @@ void           calls_settings_set_autoload_plugins           (CallsSettings
 char         **calls_settings_get_preferred_audio_codecs     (CallsSettings *self);
 void           calls_settings_set_preferred_audio_codecs     (CallsSettings      *self,
                                                               const char * const *codecs);
+gboolean       calls_settings_get_always_allow_sdes          (CallsSettings *self);
+void           calls_settings_set_always_allow_sdes          (CallsSettings *self,
+                                                              gboolean       enabled);
 
 G_END_DECLS