efi_loader: registration key in LocateProtocol()

In LocateProtocol() implement searching by the registration key returned by
RegisterNotifyProtocol().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index dd5f706..df57b3a 100644 (file)
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -2259,29 +2259,58 @@ static efi_status_t EFIAPI efi_locate_protocol(const efi_guid_t *protocol,
                                               void *registration,
                                               void **protocol_interface)
 {
-       struct list_head *lhandle;
+       struct efi_handler *handler;
        efi_status_t ret;
+       struct efi_object *efiobj;
 
        EFI_ENTRY("%pUl, %p, %p", protocol, registration, protocol_interface);
 
+       /*
+        * The UEFI spec explicitly requires a protocol even if a registration
+        * key is provided. This differs from the logic in LocateHandle().
+        */
        if (!protocol || !protocol_interface)
                return EFI_EXIT(EFI_INVALID_PARAMETER);
 
-       list_for_each(lhandle, &efi_obj_list) {
-               struct efi_object *efiobj;
-               struct efi_handler *handler;
-
-               efiobj = list_entry(lhandle, struct efi_object, link);
+       if (registration) {
+               struct efi_register_notify_event *event;
+               struct efi_protocol_notification *handle;
 
+               event = efi_check_register_notify_event(registration);
+               if (!event)
+                       return EFI_EXIT(EFI_INVALID_PARAMETER);
+               /*
+                * The UEFI spec requires to return EFI_NOT_FOUND if no
+                * protocol instance matches protocol and registration.
+                * So let's do the same for a mismatch between protocol and
+                * registration.
+                */
+               if (guidcmp(&event->protocol, protocol))
+                       goto not_found;
+               if (list_empty(&event->handles))
+                       goto not_found;
+               handle = list_first_entry(&event->handles,
+                                         struct efi_protocol_notification,
+                                         link);
+               efiobj = handle->handle;
+               list_del(&handle->link);
+               free(handle);
                ret = efi_search_protocol(efiobj, protocol, &handler);
-               if (ret == EFI_SUCCESS) {
-                       *protocol_interface = handler->protocol_interface;
-                       return EFI_EXIT(EFI_SUCCESS);
+               if (ret == EFI_SUCCESS)
+                       goto found;
+       } else {
+               list_for_each_entry(efiobj, &efi_obj_list, link) {
+                       ret = efi_search_protocol(efiobj, protocol, &handler);
+                       if (ret == EFI_SUCCESS)
+                               goto found;
                }
        }
+not_found:
        *protocol_interface = NULL;
-
        return EFI_EXIT(EFI_NOT_FOUND);
+found:
+       *protocol_interface = handler->protocol_interface;
+       return EFI_EXIT(EFI_SUCCESS);
 }
 
 /**