[gnome-settings-daemon] smartcard: Wait until smartcards are inspected before locking screen

[Benjamin Berg <bberg src gnome org>]

commit cfad586b1eb9d3b0f743edb47b458eabd4522906
Author: Ray Strode <rstrode redhat com>
Date:   Fri Feb 9 16:39:12 2018 -0500

    smartcard: Wait until smartcards are inspected before locking screen
    
    There's a race condition in the code where we check if the screen should
    be locked (because the smartcard is removed) before we necessarly check
    the smartcard's insertion status.
    
    This commit fixes the race by iterating through all smartcards at
    startup and checking their status explicitly.

 plugins/smartcard/gsd-smartcard-manager.c | 61 +++++++++++++++++++++++++------
 1 file changed, 49 insertions(+), 12 deletions(-)
---
diff --git a/plugins/smartcard/gsd-smartcard-manager.c b/plugins/smartcard/gsd-smartcard-manager.c
index a6245425..94ffdd90 100644
--- a/plugins/smartcard/gsd-smartcard-manager.c
+++ b/plugins/smartcard/gsd-smartcard-manager.c
@@ -64,10 +64,19 @@ static void     gsd_smartcard_manager_init        (GsdSmartcardManager      *sel
 static void     gsd_smartcard_manager_finalize    (GObject                  *object);
 static void     lock_screen                       (GsdSmartcardManager *self);
 static void     log_out                           (GsdSmartcardManager *self);
+static void     on_smartcards_from_driver_watched (GsdSmartcardManager *self,
+                                                   GAsyncResult        *result,
+                                                   GTask               *task);
 G_DEFINE_TYPE (GsdSmartcardManager, gsd_smartcard_manager, G_TYPE_OBJECT)
 G_DEFINE_QUARK (gsd-smartcard-manager-error, gsd_smartcard_manager_error)
 G_LOCK_DEFINE_STATIC (gsd_smartcards_watch_tasks);
 
+typedef struct {
+        SECMODModule *driver;
+        guint         idle_id;
+        GError       *error;
+} DriverRegistrationOperation;
+
 static gpointer manager_object = NULL;
 
 static void
@@ -318,6 +327,34 @@ on_smartcards_watch_task_destroyed (GsdSmartcardManager *self,
         G_UNLOCK (gsd_smartcards_watch_tasks);
 }
 
+static void
+sync_initial_tokens_from_driver (GsdSmartcardManager *self,
+                                 SECMODModule        *driver,
+                                 GHashTable          *smartcards,
+                                 GCancellable        *cancellable)
+{
+        GsdSmartcardManagerPrivate *priv = self->priv;
+        int i;
+
+        for (i = 0; i < driver->slotCount; i++) {
+                PK11SlotInfo *card;
+
+                card = driver->slots[i];
+
+                if (PK11_IsPresent (card)) {
+                        CK_SLOT_ID slot_id;
+                        slot_id = PK11_GetSlotID (card);
+
+                        g_debug ("Detected smartcard in slot %d at start up", (int) slot_id);
+
+                        g_hash_table_replace (smartcards,
+                                              GINT_TO_POINTER ((int) slot_id),
+                                              PK11_ReferenceSlot (card));
+                        gsd_smartcard_service_sync_token (priv->service, card, cancellable);
+                }
+        }
+}
+
 static void
 watch_smartcards_from_driver_async (GsdSmartcardManager *self,
                                     SECMODModule        *driver,
@@ -350,6 +387,8 @@ watch_smartcards_from_driver_async (GsdSmartcardManager *self,
                            self);
         G_UNLOCK (gsd_smartcards_watch_tasks);
 
+        sync_initial_tokens_from_driver (self, driver, operation->smartcards, cancellable);
+
         g_task_run_in_thread (task, (GTaskThreadFunc) watch_smartcards_from_driver);
 }
 
@@ -367,6 +406,10 @@ on_driver_registered (GsdSmartcardManager *self,
                       GTask               *task)
 {
         GError *error = NULL;
+        DriverRegistrationOperation *operation;
+        GsdSmartcardManagerPrivate *priv = self->priv;
+
+        operation = g_task_get_task_data (G_TASK (result));
 
         if (!register_driver_finish (self, result, &error)) {
                 g_task_return_error (task, error);
@@ -374,8 +417,13 @@ on_driver_registered (GsdSmartcardManager *self,
                 return;
         }
 
-        g_task_return_boolean (task, TRUE);
+        watch_smartcards_from_driver_async (self,
+                                            operation->driver,
+                                            priv->cancellable,
+                                            (GAsyncReadyCallback) on_smartcards_from_driver_watched,
+                                            task);
 
+        g_task_return_boolean (task, TRUE);
         g_object_unref (task);
 }
 
@@ -387,12 +435,6 @@ on_smartcards_from_driver_watched (GsdSmartcardManager *self,
         g_debug ("Done watching smartcards from driver");
 }
 
-typedef struct {
-        SECMODModule *driver;
-        guint         idle_id;
-        GError       *error;
-} DriverRegistrationOperation;
-
 static void
 destroy_driver_registration_operation (DriverRegistrationOperation *operation)
 {
@@ -477,11 +519,6 @@ activate_driver (GsdSmartcardManager *self,
                          cancellable,
                          (GAsyncReadyCallback) on_driver_registered,
                          task);
-        watch_smartcards_from_driver_async (self,
-                                            driver,
-                                            cancellable,
-                                            (GAsyncReadyCallback) on_smartcards_from_driver_watched,
-                                            task);
 }
 
 typedef struct