Adds proper key generation and exchange

This change adds proper key generation and exchange to Session::new()
and removes the garbage key.

Signed-off-by: Dhanuka Warusadura <dhanuka@gnome.org>

server/src/daemon/session.rs

@@ -35,8 +35,14 @@ impl Session {
         manager: Arc<Mutex<ServiceManager>>,
         sessions_counter: i32,
     ) -> (Self, Option<Key>) {
-        // make use of the keys
-        let service_key = vec![0];
+        let service_key = if client_public_key.is_none() {
+            Some(Key::new(vec![0]))
+        } else {
+            let private_key = Key::generate_private_key();
+            let public_key = Key::generate_public_key(&private_key);
+            Some(Key::from(public_key))
+        };
+
         let instance = Self {
             client_public_key: Arc::new(client_public_key),
             path: OwnedObjectPath::try_from(format!(
@@ -47,7 +53,7 @@ impl Session {
             manager,
         };
 
-        (instance, Some(Key::new(service_key)))
+        (instance, service_key)
     }
 
     pub fn path(&self) -> ObjectPath<'_> {