1 files changed, 36 insertions, 0 deletions
diff --git a/lib/libavb/avb_footer.c b/lib/libavb/avb_footer.c
new file mode 100644
index 0000000000..f8b6873942
--- /dev/null
+++ b/lib/libavb/avb_footer.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * SPDX-License-Identifier:	MIT
+ */
+
+#include "avb_footer.h"
+#include "avb_util.h"
+
+bool avb_footer_validate_and_byteswap(const AvbFooter* src, AvbFooter* dest) {
+  avb_memcpy(dest, src, sizeof(AvbFooter));
+
+  dest->version_major = avb_be32toh(dest->version_major);
+  dest->version_minor = avb_be32toh(dest->version_minor);
+
+  dest->original_image_size = avb_be64toh(dest->original_image_size);
+  dest->vbmeta_offset = avb_be64toh(dest->vbmeta_offset);
+  dest->vbmeta_size = avb_be64toh(dest->vbmeta_size);
+
+  /* Check that magic is correct. */
+  if (avb_safe_memcmp(dest->magic, AVB_FOOTER_MAGIC, AVB_FOOTER_MAGIC_LEN) !=
+      0) {
+    avb_error("Footer magic is incorrect.\n");
+    return false;
+  }
+
+  /* Ensure we don't attempt to access any fields if the footer major
+   * version is not supported.
+   */
+  if (dest->version_major > AVB_FOOTER_VERSION_MAJOR) {
+    avb_error("No support for footer version.\n");
+    return false;
+  }
+
+  return true;
+}