diff --git a/tools/releasetools/verity_utils.py b/tools/releasetools/verity_utils.py
index c512ef3..626a1dd 100644
--- a/tools/releasetools/verity_utils.py
+++ b/tools/releasetools/verity_utils.py
@@ -16,13 +16,354 @@
 
 from __future__ import print_function
 
+import os.path
+import shlex
 import struct
 
 import common
-from build_image import (AdjustPartitionSizeForVerity, GetVerityTreeSize,
-                         GetVerityMetadataSize, BuildVerityTree)
+import sparse_img
 from rangelib import RangeSet
 
+OPTIONS = common.OPTIONS
+BLOCK_SIZE = common.BLOCK_SIZE
+FIXED_SALT = "aee087a5be3b982978c923f566a94613496b417f2af592639bc80d141e34dfe7"
+
+
+class BuildVerityImageError(Exception):
+  """An Exception raised during verity image building."""
+
+  def __init__(self, message):
+    Exception.__init__(self, message)
+
+
+def GetVerityFECSize(partition_size):
+  cmd = ["fec", "-s", str(partition_size)]
+  output = common.RunAndCheckOutput(cmd, verbose=False)
+  return int(output)
+
+
+def GetVerityTreeSize(partition_size):
+  cmd = ["build_verity_tree", "-s", str(partition_size)]
+  output = common.RunAndCheckOutput(cmd, verbose=False)
+  return int(output)
+
+
+def GetVerityMetadataSize(partition_size):
+  cmd = ["build_verity_metadata.py", "size", str(partition_size)]
+  output = common.RunAndCheckOutput(cmd, verbose=False)
+  return int(output)
+
+
+def GetVeritySize(partition_size, fec_supported):
+  verity_tree_size = GetVerityTreeSize(partition_size)
+  verity_metadata_size = GetVerityMetadataSize(partition_size)
+  verity_size = verity_tree_size + verity_metadata_size
+  if fec_supported:
+    fec_size = GetVerityFECSize(partition_size + verity_size)
+    return verity_size + fec_size
+  return verity_size
+
+
+def GetSimgSize(image_file):
+  simg = sparse_img.SparseImage(image_file, build_map=False)
+  return simg.blocksize * simg.total_blocks
+
+
+def ZeroPadSimg(image_file, pad_size):
+  blocks = pad_size // BLOCK_SIZE
+  print("Padding %d blocks (%d bytes)" % (blocks, pad_size))
+  simg = sparse_img.SparseImage(image_file, mode="r+b", build_map=False)
+  simg.AppendFillChunk(0, blocks)
+
+
+def AdjustPartitionSizeForVerity(partition_size, fec_supported):
+  """Modifies the provided partition size to account for the verity metadata.
+
+  This information is used to size the created image appropriately.
+
+  Args:
+    partition_size: the size of the partition to be verified.
+
+  Returns:
+    A tuple of the size of the partition adjusted for verity metadata, and
+    the size of verity metadata.
+  """
+  key = "%d %d" % (partition_size, fec_supported)
+  if key in AdjustPartitionSizeForVerity.results:
+    return AdjustPartitionSizeForVerity.results[key]
+
+  hi = partition_size
+  if hi % BLOCK_SIZE != 0:
+    hi = (hi // BLOCK_SIZE) * BLOCK_SIZE
+
+  # verity tree and fec sizes depend on the partition size, which
+  # means this estimate is always going to be unnecessarily small
+  verity_size = GetVeritySize(hi, fec_supported)
+  lo = partition_size - verity_size
+  result = lo
+
+  # do a binary search for the optimal size
+  while lo < hi:
+    i = ((lo + hi) // (2 * BLOCK_SIZE)) * BLOCK_SIZE
+    v = GetVeritySize(i, fec_supported)
+    if i + v <= partition_size:
+      if result < i:
+        result = i
+        verity_size = v
+      lo = i + BLOCK_SIZE
+    else:
+      hi = i
+
+  if OPTIONS.verbose:
+    print("Adjusted partition size for verity, partition_size: {},"
+          " verity_size: {}".format(result, verity_size))
+  AdjustPartitionSizeForVerity.results[key] = (result, verity_size)
+  return (result, verity_size)
+
+
+AdjustPartitionSizeForVerity.results = {}
+
+
+def BuildVerityFEC(sparse_image_path, verity_path, verity_fec_path,
+                   padding_size):
+  cmd = ["fec", "-e", "-p", str(padding_size), sparse_image_path,
+         verity_path, verity_fec_path]
+  common.RunAndCheckOutput(cmd)
+
+
+def BuildVerityTree(sparse_image_path, verity_image_path):
+  cmd = ["build_verity_tree", "-A", FIXED_SALT, sparse_image_path,
+         verity_image_path]
+  output = common.RunAndCheckOutput(cmd)
+  root, salt = output.split()
+  return root, salt
+
+
+def BuildVerityMetadata(image_size, verity_metadata_path, root_hash, salt,
+                        block_device, signer_path, key, signer_args,
+                        verity_disable):
+  cmd = ["build_verity_metadata.py", "build", str(image_size),
+         verity_metadata_path, root_hash, salt, block_device, signer_path, key]
+  if signer_args:
+    cmd.append("--signer_args=\"%s\"" % (' '.join(signer_args),))
+  if verity_disable:
+    cmd.append("--verity_disable")
+  common.RunAndCheckOutput(cmd)
+
+
+def Append2Simg(sparse_image_path, unsparse_image_path, error_message):
+  """Appends the unsparse image to the given sparse image.
+
+  Args:
+    sparse_image_path: the path to the (sparse) image
+    unsparse_image_path: the path to the (unsparse) image
+
+  Raises:
+    BuildVerityImageError: On error.
+  """
+  cmd = ["append2simg", sparse_image_path, unsparse_image_path]
+  try:
+    common.RunAndCheckOutput(cmd)
+  except:
+    raise BuildVerityImageError(error_message)
+
+
+def Append(target, file_to_append, error_message):
+  """Appends file_to_append to target.
+
+  Raises:
+    BuildVerityImageError: On error.
+  """
+  try:
+    with open(target, "a") as out_file, open(file_to_append, "r") as input_file:
+      for line in input_file:
+        out_file.write(line)
+  except IOError:
+    raise BuildVerityImageError(error_message)
+
+
+def BuildVerifiedImage(data_image_path, verity_image_path,
+                       verity_metadata_path, verity_fec_path,
+                       padding_size, fec_supported):
+  Append(
+      verity_image_path, verity_metadata_path,
+      "Could not append verity metadata!")
+
+  if fec_supported:
+    # Build FEC for the entire partition, including metadata.
+    BuildVerityFEC(
+        data_image_path, verity_image_path, verity_fec_path, padding_size)
+    Append(verity_image_path, verity_fec_path, "Could not append FEC!")
+
+  Append2Simg(
+      data_image_path, verity_image_path, "Could not append verity data!")
+
+
+def MakeVerityEnabledImage(out_file, fec_supported, prop_dict):
+  """Creates an image that is verifiable using dm-verity.
+
+  Args:
+    out_file: the location to write the verifiable image at
+    prop_dict: a dictionary of properties required for image creation and
+               verification
+
+  Raises:
+    AssertionError: On invalid partition sizes.
+  """
+  # get properties
+  image_size = int(prop_dict["image_size"])
+  block_dev = prop_dict["verity_block_device"]
+  signer_key = prop_dict["verity_key"] + ".pk8"
+  if OPTIONS.verity_signer_path is not None:
+    signer_path = OPTIONS.verity_signer_path
+  else:
+    signer_path = prop_dict["verity_signer_cmd"]
+  signer_args = OPTIONS.verity_signer_args
+
+  tempdir_name = common.MakeTempDir(suffix="_verity_images")
+
+  # Get partial image paths.
+  verity_image_path = os.path.join(tempdir_name, "verity.img")
+  verity_metadata_path = os.path.join(tempdir_name, "verity_metadata.img")
+  verity_fec_path = os.path.join(tempdir_name, "verity_fec.img")
+
+  # Build the verity tree and get the root hash and salt.
+  root_hash, salt = BuildVerityTree(out_file, verity_image_path)
+
+  # Build the metadata blocks.
+  verity_disable = "verity_disable" in prop_dict
+  BuildVerityMetadata(
+      image_size, verity_metadata_path, root_hash, salt, block_dev, signer_path,
+      signer_key, signer_args, verity_disable)
+
+  # Build the full verified image.
+  partition_size = int(prop_dict["partition_size"])
+  verity_size = int(prop_dict["verity_size"])
+
+  padding_size = partition_size - image_size - verity_size
+  assert padding_size >= 0
+
+  BuildVerifiedImage(
+      out_file, verity_image_path, verity_metadata_path, verity_fec_path,
+      padding_size, fec_supported)
+
+
+def AVBCalcMaxImageSize(avbtool, footer_type, partition_size, additional_args):
+  """Calculates max image size for a given partition size.
+
+  Args:
+    avbtool: String with path to avbtool.
+    footer_type: 'hash' or 'hashtree' for generating footer.
+    partition_size: The size of the partition in question.
+    additional_args: Additional arguments to pass to "avbtool add_hash_footer"
+        or "avbtool add_hashtree_footer".
+
+  Returns:
+    The maximum image size.
+
+  Raises:
+    BuildVerityImageError: On invalid image size.
+  """
+  cmd = [avbtool, "add_%s_footer" % footer_type,
+         "--partition_size", str(partition_size), "--calc_max_image_size"]
+  cmd.extend(shlex.split(additional_args))
+
+  output = common.RunAndCheckOutput(cmd)
+  image_size = int(output)
+  if image_size <= 0:
+    raise BuildVerityImageError(
+        "Invalid max image size: {}".format(output))
+  return image_size
+
+
+def AVBCalcMinPartitionSize(image_size, size_calculator):
+  """Calculates min partition size for a given image size.
+
+  Args:
+    image_size: The size of the image in question.
+    size_calculator: The function to calculate max image size
+        for a given partition size.
+
+  Returns:
+    The minimum partition size required to accommodate the image size.
+  """
+  # Use image size as partition size to approximate final partition size.
+  image_ratio = size_calculator(image_size) / float(image_size)
+
+  # Prepare a binary search for the optimal partition size.
+  lo = int(image_size / image_ratio) // BLOCK_SIZE * BLOCK_SIZE - BLOCK_SIZE
+
+  # Ensure lo is small enough: max_image_size should <= image_size.
+  delta = BLOCK_SIZE
+  max_image_size = size_calculator(lo)
+  while max_image_size > image_size:
+    image_ratio = max_image_size / float(lo)
+    lo = int(image_size / image_ratio) // BLOCK_SIZE * BLOCK_SIZE - delta
+    delta *= 2
+    max_image_size = size_calculator(lo)
+
+  hi = lo + BLOCK_SIZE
+
+  # Ensure hi is large enough: max_image_size should >= image_size.
+  delta = BLOCK_SIZE
+  max_image_size = size_calculator(hi)
+  while max_image_size < image_size:
+    image_ratio = max_image_size / float(hi)
+    hi = int(image_size / image_ratio) // BLOCK_SIZE * BLOCK_SIZE + delta
+    delta *= 2
+    max_image_size = size_calculator(hi)
+
+  partition_size = hi
+
+  # Start to binary search.
+  while lo < hi:
+    mid = ((lo + hi) // (2 * BLOCK_SIZE)) * BLOCK_SIZE
+    max_image_size = size_calculator(mid)
+    if max_image_size >= image_size:  # if mid can accommodate image_size
+      if mid < partition_size:  # if a smaller partition size is found
+        partition_size = mid
+      hi = mid
+    else:
+      lo = mid + BLOCK_SIZE
+
+  if OPTIONS.verbose:
+    print("AVBCalcMinPartitionSize({}): partition_size: {}.".format(
+        image_size, partition_size))
+
+  return partition_size
+
+
+def AVBAddFooter(image_path, avbtool, footer_type, partition_size,
+                 partition_name, key_path, algorithm, salt,
+                 additional_args):
+  """Adds dm-verity hashtree and AVB metadata to an image.
+
+  Args:
+    image_path: Path to image to modify.
+    avbtool: String with path to avbtool.
+    footer_type: 'hash' or 'hashtree' for generating footer.
+    partition_size: The size of the partition in question.
+    partition_name: The name of the partition - will be embedded in metadata.
+    key_path: Path to key to use or None.
+    algorithm: Name of algorithm to use or None.
+    salt: The salt to use (a hexadecimal string) or None.
+    additional_args: Additional arguments to pass to "avbtool add_hash_footer"
+        or "avbtool add_hashtree_footer".
+  """
+  cmd = [avbtool, "add_%s_footer" % footer_type,
+         "--partition_size", partition_size,
+         "--partition_name", partition_name,
+         "--image", image_path]
+
+  if key_path and algorithm:
+    cmd.extend(["--key", key_path, "--algorithm", algorithm])
+  if salt:
+    cmd.extend(["--salt", salt])
+
+  cmd.extend(shlex.split(additional_args))
+
+  common.RunAndCheckOutput(cmd)
+
 
 class HashtreeInfoGenerationError(Exception):
   """An Exception raised during hashtree info generation."""