verify framework.

include/grub/file.h

@@ -170,7 +170,7 @@ extern grub_disk_read_hook_t EXPORT_VAR(grub_file_progress_hook);
 /* Filters with lower ID are executed first.  */
 typedef enum grub_file_filter_id
   {
-    GRUB_FILE_FILTER_PUBKEY,
+    GRUB_FILE_FILTER_VERIFY,
     GRUB_FILE_FILTER_GZIO,
     GRUB_FILE_FILTER_XZIO,
     GRUB_FILE_FILTER_LZOPIO,

include/grub/list.h

@@ -35,6 +35,7 @@ void EXPORT_FUNC(grub_list_push) (grub_list_t *head, grub_list_t item);
 void EXPORT_FUNC(grub_list_remove) (grub_list_t item);
 
 #define FOR_LIST_ELEMENTS(var, list) for ((var) = (list); (var); (var) = (var)->next)
+#define FOR_LIST_ELEMENTS_NEXT(var, list) for ((var) = (var)->next; (var); (var) = (var)->next)
 #define FOR_LIST_ELEMENTS_SAFE(var, nxt, list) for ((var) = (list), (nxt) = ((var) ? (var)->next : 0); (var); (var) = (nxt), ((nxt) = (var) ? (var)->next : 0))
 
 static inline void *

include/grub/verify.h

@@ -0,0 +1,42 @@
+#include <grub/file.h>
+#include <grub/list.h>
+
+enum grub_verify_flags
+  {
+    GRUB_VERIFY_FLAGS_SKIP_VERIFICATION = 1,
+    GRUB_VERIFY_FLAGS_SINGLE_CHUNK = 2,
+  };
+
+struct grub_file_verifier
+{
+  struct grub_file_verifier *next;
+  struct grub_file_verifier **prev;
+
+  const char *name;
+
+  /* Check if file needs to be verified and set up context.  */
+  /* init/read/fini is structured in the same way as hash interface.  */
+  grub_err_t (*init) (grub_file_t io, enum grub_file_type type,
+		      void **context, enum grub_verify_flags *verify_flags);
+  /* Right now we pass the whole file in one call but it
+     will change in the future. If you insist on single buffer we can
+     you need to set GRUB_VERIFY_FLAGS_SINGLE_CHUNK in verify_flags.
+  */
+  grub_err_t (*write) (void *context, void *buf, grub_size_t sz);
+  grub_err_t (*fini) (void *context);
+  void (*close) (void *context);
+};
+
+extern struct grub_file_verifier *grub_file_verifiers;
+
+static inline void
+grub_verifier_register (struct grub_file_verifier *ver)
+{
+  grub_list_push (GRUB_AS_LIST_P (&grub_file_verifiers), GRUB_AS_LIST (ver));
+}
+
+static inline void
+grub_verifier_unregister (struct grub_file_verifier *ver)
+{
+  grub_list_remove (GRUB_AS_LIST (ver));
+}