images: protobuf definitions for memfd_secret

Adds protobuf definitions needed to checkpoint and restore
memfd_secret fd.

Signed-off-by: Dhanuka Warusadura <[email protected]>

images/memfd-secret.proto

@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: MIT
+
+syntax = "proto2";
+
+import "opts.proto";
+import "fown.proto";
+
+message memfd_secret_file_entry {
+        required uint32		id		= 1;
+	required uint32		flags		= 2 [(criu).flags = "rfile.flags"];
+	required uint64		pos		= 3;
+	required fown_entry	fown		= 4;
+	required uint32		inode_id	= 5;
+};
+
+message memfd_secret_inode_entry {
+        required uint32 uid = 1;
+        required uint32 gid = 2;
+        required uint64 size = 3;
+        required uint32 secretmem_id = 4;
+        required uint64 inode_id = 5;
+};