diff --git a/tools/releasetools/verity_utils.py b/tools/releasetools/verity_utils.py
index 8faa2d1..a08ddbe 100644
--- a/tools/releasetools/verity_utils.py
+++ b/tools/releasetools/verity_utils.py
@@ -26,6 +26,7 @@
 import os.path
 import shlex
 import struct
+import sys
 
 import common
 import sparse_img
@@ -739,6 +740,30 @@
   return int(output.split()[0]) * 1024
 
 
+def CalculateVbmetaDigest(extracted_dir, avbtool):
+  """Calculates the vbmeta digest of the images in the extracted target_file"""
+
+  images_dir = common.MakeTempDir()
+  for name in ("PREBUILT_IMAGES", "RADIO", "IMAGES"):
+    path = os.path.join(extracted_dir, name)
+    if not os.path.exists(path):
+      continue
+
+    # Create symlink for image files under PREBUILT_IMAGES, RADIO and IMAGES,
+    # and put them into one directory.
+    for filename in os.listdir(path):
+      if not filename.endswith(".img"):
+        continue
+      symlink_path = os.path.join(images_dir, filename)
+      # The files in latter directory overwrite the existing links
+      common.RunAndCheckOutput(
+        ['ln', '-sf', os.path.join(path, filename), symlink_path])
+
+  cmd = [avbtool, "calculate_vbmeta_digest", "--image",
+         os.path.join(images_dir, 'vbmeta.img')]
+  return common.RunAndCheckOutput(cmd)
+
+
 def main(argv):
   if len(argv) != 2:
     print(__doc__)