diff --git a/core/Makefile b/core/Makefile
index 517410a..2df67e9 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -3045,33 +3045,42 @@
 # -----------------------------------------------------------------
 # host tools needed to build dist and OTA packages
 
-build_ota_package := true
-ifeq ($(TARGET_SKIP_OTA_PACKAGE),true)
-build_ota_package := false
-endif
 ifeq ($(BUILD_OS),darwin)
-build_ota_package := false
-endif
-ifneq ($(strip $(SANITIZE_TARGET)),)
-build_ota_package := false
-endif
-ifeq ($(TARGET_PRODUCT),sdk)
-build_ota_package := false
-endif
-ifneq ($(filter generic%,$(TARGET_DEVICE)),)
-build_ota_package := false
-endif
-ifeq ($(TARGET_NO_KERNEL),true)
-build_ota_package := false
-endif
-ifeq ($(recovery_fstab),)
-build_ota_package := false
-endif
-ifeq ($(TARGET_BUILD_PDK),true)
-build_ota_package := false
+  build_ota_package := false
+  build_otatools_package := false
+else
+  # set build_ota_package, and allow opt-out below
+  build_ota_package := true
+  ifeq ($(TARGET_SKIP_OTA_PACKAGE),true)
+    build_ota_package := false
+  endif
+  ifneq ($(strip $(SANITIZE_TARGET)),)
+    build_ota_package := false
+  endif
+  ifeq ($(TARGET_PRODUCT),sdk)
+    build_ota_package := false
+  endif
+  ifneq ($(filter generic%,$(TARGET_DEVICE)),)
+    build_ota_package := false
+  endif
+  ifeq ($(TARGET_NO_KERNEL),true)
+    build_ota_package := false
+  endif
+  ifeq ($(recovery_fstab),)
+    build_ota_package := false
+  endif
+  ifeq ($(TARGET_BUILD_PDK),true)
+    build_ota_package := false
+  endif
+
+  # set build_otatools_package, and allow opt-out below
+  build_otatools_package := true
+  ifeq ($(TARGET_SKIP_OTATOOLS_PACKAGE),true)
+    build_otatools_package := false
+  endif
 endif
 
-ifeq ($(build_ota_package),true)
+ifeq ($(build_otatools_package),true)
 OTATOOLS :=  $(HOST_OUT_EXECUTABLES)/minigzip \
   $(HOST_OUT_EXECUTABLES)/aapt \
   $(HOST_OUT_EXECUTABLES)/checkvintf \
@@ -3160,13 +3169,23 @@
 
 OTATOOLS_DEPS := \
   system/extras/ext4_utils/mke2fs.conf \
-  $(sort $(shell find external/avb/test/data -type f -name "testkey_*.pem" -o \
-      -name "atx_metadata.bin")) \
-  $(sort $(shell find system/update_engine/scripts -name "*.pyc" -prune -o -type f -print)) \
   $(sort $(shell find build/target/product/security -type f -name "*.x509.pem" -o -name "*.pk8" -o \
-      -name verity_key)) \
+      -name verity_key))
+
+ifneq (,$(wildcard device))
+OTATOOLS_DEPS += \
   $(sort $(shell find device $(wildcard vendor) -type f -name "*.pk8" -o -name "verifiedboot*" -o \
       -name "*.x509.pem" -o -name "oem*.prop"))
+endif
+ifneq (,$(wildcard external/avb))
+OTATOOLS_DEPS += \
+  $(sort $(shell find external/avb/test/data -type f -name "testkey_*.pem" -o \
+      -name "atx_metadata.bin"))
+endif
+ifneq (,$(wildcard system/update_engine))
+OTATOOLS_DEPS += \
+  $(sort $(shell find system/update_engine/scripts -name "*.pyc" -prune -o -type f -print))
+endif
 
 OTATOOLS_RELEASETOOLS := \
   $(sort $(shell find build/make/tools/releasetools -name "*.pyc" -prune -o -type f))
@@ -3189,7 +3208,7 @@
 .PHONY: otatools-package
 otatools-package: $(BUILT_OTATOOLS_PACKAGE)
 
-endif # build_ota_package
+endif # build_otatools_package
 
 # -----------------------------------------------------------------
 # A zip of the directories that map to the target filesystem.
diff --git a/core/config_sanitizers.mk b/core/config_sanitizers.mk
index e58f676..be1b124 100644
--- a/core/config_sanitizers.mk
+++ b/core/config_sanitizers.mk
@@ -212,10 +212,6 @@
   my_sanitize := $(filter-out scudo,$(my_sanitize))
 endif
 
-ifneq ($(filter scudo,$(my_sanitize)),)
-  my_shared_libraries += $($(LOCAL_2ND_ARCH_VAR_PREFIX)SCUDO_RUNTIME_LIBRARY)
-endif
-
 # Undefined symbols can occur if a non-sanitized library links
 # sanitized static libraries. That's OK, because the executable
 # always depends on the ASan runtime library, which defines these
@@ -375,7 +371,7 @@
     endif
   endif
   ifneq ($(filter unsigned-integer-overflow signed-integer-overflow integer,$(my_sanitize)),)
-    ifeq ($(filter unsigned-integer-overflow signed-integer overflow integer,$(my_sanitize_diag)),)
+    ifeq ($(filter unsigned-integer-overflow signed-integer-overflow integer,$(my_sanitize_diag)),)
       ifeq ($(filter cfi,$(my_sanitize_diag)),)
         ifeq ($(filter address hwaddress,$(my_sanitize)),)
           my_cflags += -fsanitize-minimal-runtime
@@ -387,6 +383,18 @@
   endif
 endif
 
+# For Scudo, we opt for the minimal runtime, unless some diagnostics are enabled.
+ifneq ($(filter scudo,$(my_sanitize)),)
+  ifeq ($(filter unsigned-integer-overflow signed-integer-overflow integer cfi,$(my_sanitize_diag)),)
+    my_cflags += -fsanitize-minimal-runtime
+  endif
+  ifneq ($(filter -fsanitize-minimal-runtime,$(my_cflags)),)
+    my_shared_libraries += $($(LOCAL_2ND_ARCH_VAR_PREFIX)SCUDO_MINIMAL_RUNTIME_LIBRARY)
+  else
+    my_shared_libraries += $($(LOCAL_2ND_ARCH_VAR_PREFIX)SCUDO_RUNTIME_LIBRARY)
+  endif
+endif
+
 ifneq ($(strip $(LOCAL_SANITIZE_RECOVER)),)
   recover_arg := $(subst $(space),$(comma),$(LOCAL_SANITIZE_RECOVER)),
   my_cflags += -fsanitize-recover=$(recover_arg)
diff --git a/core/dex_preopt_libart_boot.mk b/core/dex_preopt_libart_boot.mk
index a56fd5e..14955f0 100644
--- a/core/dex_preopt_libart_boot.mk
+++ b/core/dex_preopt_libart_boot.mk
@@ -108,7 +108,7 @@
 		--instruction-set-variant=$($(PRIVATE_2ND_ARCH_VAR_PREFIX)DEX2OAT_TARGET_CPU_VARIANT) \
 		--instruction-set-features=$($(PRIVATE_2ND_ARCH_VAR_PREFIX)DEX2OAT_TARGET_INSTRUCTION_SET_FEATURES) \
 		--android-root=$(PRODUCT_OUT)/system \
-		--multi-image --no-inline-from=core-oj.jar \
+		--no-inline-from=core-oj.jar \
 		--abort-on-hard-verifier-error \
 		--abort-on-soft-verifier-error \
 		$(PRODUCT_DEX_PREOPT_BOOT_FLAGS) $(GLOBAL_DEXPREOPT_FLAGS) $(ART_BOOT_IMAGE_EXTRA_ARGS) \
diff --git a/tools/releasetools/build_image.py b/tools/releasetools/build_image.py
index 42f05a7..43c91da 100755
--- a/tools/releasetools/build_image.py
+++ b/tools/releasetools/build_image.py
@@ -29,18 +29,14 @@
 import os
 import os.path
 import re
-import shlex
 import shutil
 import sys
 
 import common
-import sparse_img
-
+import verity_utils
 
 OPTIONS = common.OPTIONS
-
-FIXED_SALT = "aee087a5be3b982978c923f566a94613496b417f2af592639bc80d141e34dfe7"
-BLOCK_SIZE = 4096
+BLOCK_SIZE = common.BLOCK_SIZE
 BYTES_IN_MB = 1024 * 1024
 
 
@@ -51,34 +47,6 @@
     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 GetDiskUsage(path):
   """Returns the number of bytes that "path" occupies on host.
 
@@ -102,258 +70,6 @@
   return int(output.split()[0]) * 512
 
 
-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 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:
-    BuildImageError: 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 BuildImageError(
-        "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)
-
-
-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:
-    BuildImageError: On error.
-  """
-  cmd = ["append2simg", sparse_image_path, unsparse_image_path]
-  try:
-    common.RunAndCheckOutput(cmd)
-  except:
-    raise BuildImageError(error_message)
-
-
-def Append(target, file_to_append, error_message):
-  """Appends file_to_append to target.
-
-  Raises:
-    BuildImageError: 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 BuildImageError(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 UnsparseImage(sparse_image_path, replace=True):
   img_dir = os.path.dirname(sparse_image_path)
   unsparse_image_path = "unsparse_" + os.path.basename(sparse_image_path)
@@ -372,56 +88,6 @@
   return unsparse_image_path
 
 
-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.
-    BuildImageError: On other errors.
-  """
-  # 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 ConvertBlockMapToBaseFs(block_map_file):
   base_fs_file = common.MakeTempFile(prefix="script_gen_", suffix=".base_fs")
   convert_command = ["blk_alloc_to_base_fs", block_map_file, base_fs_file]
@@ -570,9 +236,9 @@
     # Adjust partition_size to add more space for AVB footer, to prevent
     # it from consuming partition_reserved_size.
     if avb_footer_type:
-      size = AVBCalcMinPartitionSize(
+      size = verity_utils.AVBCalcMinPartitionSize(
           size,
-          lambda x: AVBCalcMaxImageSize(
+          lambda x: verity_utils.AVBCalcMaxImageSize(
               avbtool, avb_footer_type, x, avb_signing_args))
     prop_dict["partition_size"] = str(size)
     if OPTIONS.verbose:
@@ -583,7 +249,7 @@
   # Adjust the image size to make room for the hashes if this is to be verified.
   if verity_supported and is_verity_partition:
     partition_size = int(prop_dict.get("partition_size"))
-    image_size, verity_size = AdjustPartitionSizeForVerity(
+    image_size, verity_size = verity_utils.AdjustPartitionSizeForVerity(
         partition_size, verity_fec_supported)
     prop_dict["image_size"] = str(image_size)
     prop_dict["verity_size"] = str(verity_size)
@@ -592,7 +258,7 @@
   if avb_footer_type:
     partition_size = prop_dict["partition_size"]
     # avb_add_hash_footer_args or avb_add_hashtree_footer_args.
-    max_image_size = AVBCalcMaxImageSize(
+    max_image_size = verity_utils.AVBCalcMaxImageSize(
         avbtool, avb_footer_type, partition_size, avb_signing_args)
     prop_dict["image_size"] = str(max_image_size)
 
@@ -709,17 +375,18 @@
   if not fs_spans_partition:
     mount_point = prop_dict.get("mount_point")
     image_size = int(prop_dict["image_size"])
-    sparse_image_size = GetSimgSize(out_file)
+    sparse_image_size = verity_utils.GetSimgSize(out_file)
     if sparse_image_size > image_size:
       raise BuildImageError(
           "Error: {} image size of {} is larger than partition size of "
           "{}".format(mount_point, sparse_image_size, image_size))
     if verity_supported and is_verity_partition:
-      ZeroPadSimg(out_file, image_size - sparse_image_size)
+      verity_utils.ZeroPadSimg(out_file, image_size - sparse_image_size)
 
   # Create the verified image if this is to be verified.
   if verity_supported and is_verity_partition:
-    MakeVerityEnabledImage(out_file, verity_fec_supported, prop_dict)
+    verity_utils.MakeVerityEnabledImage(
+        out_file, verity_fec_supported, prop_dict)
 
   # Add AVB HASH or HASHTREE footer (metadata).
   if avb_footer_type:
@@ -729,7 +396,7 @@
     key_path = prop_dict.get("avb_key_path")
     algorithm = prop_dict.get("avb_algorithm")
     salt = prop_dict.get("avb_salt")
-    AVBAddFooter(
+    verity_utils.AVBAddFooter(
         out_file, avbtool, avb_footer_type, partition_size, partition_name,
         key_path, algorithm, salt, avb_signing_args)
 
diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index d1bfc8f..7cca766 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -73,6 +73,9 @@
 
 OPTIONS = Options()
 
+# The block size that's used across the releasetools scripts.
+BLOCK_SIZE = 4096
+
 # Values for "certificate" in apkcerts that mean special things.
 SPECIAL_CERT_STRINGS = ("PRESIGNED", "EXTERNAL")
 
diff --git a/tools/releasetools/test_add_img_to_target_files.py b/tools/releasetools/test_add_img_to_target_files.py
index cc7b887..ad22b72 100644
--- a/tools/releasetools/test_add_img_to_target_files.py
+++ b/tools/releasetools/test_add_img_to_target_files.py
@@ -16,7 +16,6 @@
 
 import os
 import os.path
-import unittest
 import zipfile
 
 import common
@@ -30,14 +29,11 @@
 OPTIONS = common.OPTIONS
 
 
-class AddImagesToTargetFilesTest(unittest.TestCase):
+class AddImagesToTargetFilesTest(test_utils.ReleaseToolsTestCase):
 
   def setUp(self):
     OPTIONS.input_tmp = common.MakeTempDir()
 
-  def tearDown(self):
-    common.Cleanup()
-
   def _verifyCareMap(self, expected, file_name):
     """Parses the care_map.pb; and checks the content in plain text."""
     text_file = common.MakeTempFile(prefix="caremap-", suffix=".txt")
diff --git a/tools/releasetools/test_blockimgdiff.py b/tools/releasetools/test_blockimgdiff.py
index 124b4d5..857026e 100644
--- a/tools/releasetools/test_blockimgdiff.py
+++ b/tools/releasetools/test_blockimgdiff.py
@@ -14,17 +14,14 @@
 # limitations under the License.
 #
 
-from __future__ import print_function
-
-import unittest
-
 import common
-from blockimgdiff import (BlockImageDiff, EmptyImage, HeapItem, ImgdiffStats,
-                          Transfer)
+from blockimgdiff import (
+    BlockImageDiff, EmptyImage, HeapItem, ImgdiffStats, Transfer)
 from rangelib import RangeSet
+from test_utils import ReleaseToolsTestCase
 
 
-class HealpItemTest(unittest.TestCase):
+class HealpItemTest(ReleaseToolsTestCase):
 
   class Item(object):
     def __init__(self, score):
@@ -54,7 +51,7 @@
     self.assertFalse(item)
 
 
-class BlockImageDiffTest(unittest.TestCase):
+class BlockImageDiffTest(ReleaseToolsTestCase):
 
   def test_GenerateDigraphOrder(self):
     """Make sure GenerateDigraph preserves the order.
@@ -245,7 +242,7 @@
         block_image_diff.imgdiff_stats.stats)
 
 
-class ImgdiffStatsTest(unittest.TestCase):
+class ImgdiffStatsTest(ReleaseToolsTestCase):
 
   def test_Log(self):
     imgdiff_stats = ImgdiffStats()
diff --git a/tools/releasetools/test_build_image.py b/tools/releasetools/test_build_image.py
index a2df278..634c6b1 100644
--- a/tools/releasetools/test_build_image.py
+++ b/tools/releasetools/test_build_image.py
@@ -15,33 +15,20 @@
 #
 
 import filecmp
-import math
 import os.path
-import random
-import unittest
 
 import common
 from build_image import (
-    AVBCalcMinPartitionSize, BLOCK_SIZE, BuildImageError, CheckHeadroom,
-    SetUpInDirAndFsConfig)
+    BuildImageError, CheckHeadroom, SetUpInDirAndFsConfig)
+from test_utils import ReleaseToolsTestCase
 
 
-class BuildImageTest(unittest.TestCase):
+class BuildImageTest(ReleaseToolsTestCase):
 
   # Available: 1000 blocks.
   EXT4FS_OUTPUT = (
       "Created filesystem with 2777/129024 inodes and 515099/516099 blocks")
 
-  def setUp(self):
-    # To test AVBCalcMinPartitionSize(), by using 200MB to 2GB image size.
-    #   -  51200 = 200MB * 1024 * 1024 / 4096
-    #   - 524288 = 2GB * 1024 * 1024 * 1024 / 4096
-    self._image_sizes = [BLOCK_SIZE * random.randint(51200, 524288) + offset
-                         for offset in range(BLOCK_SIZE)]
-
-  def tearDown(self):
-    common.Cleanup()
-
   def test_CheckHeadroom_SizeUnderLimit(self):
     # Required headroom: 1000 blocks.
     prop_dict = {
@@ -189,51 +176,3 @@
     self.assertIn('fs-config-system\n', fs_config_data)
     self.assertIn('fs-config-root\n', fs_config_data)
     self.assertEqual('/', prop_dict['mount_point'])
-
-  def test_AVBCalcMinPartitionSize_LinearFooterSize(self):
-    """Tests with footer size which is linear to partition size."""
-    for image_size in self._image_sizes:
-      for ratio in 0.95, 0.56, 0.22:
-        expected_size = common.RoundUpTo4K(int(math.ceil(image_size / ratio)))
-        self.assertEqual(
-            expected_size,
-            AVBCalcMinPartitionSize(image_size, lambda x: int(x * ratio)))
-
-  def test_AVBCalcMinPartitionSize_SlowerGrowthFooterSize(self):
-    """Tests with footer size which grows slower than partition size."""
-
-    def _SizeCalculator(partition_size):
-      """Footer size is the power of 0.95 of partition size."""
-      # Minus footer size to return max image size.
-      return partition_size - int(math.pow(partition_size, 0.95))
-
-    for image_size in self._image_sizes:
-      min_partition_size = AVBCalcMinPartitionSize(image_size, _SizeCalculator)
-      # Checks min_partition_size can accommodate image_size.
-      self.assertGreaterEqual(
-          _SizeCalculator(min_partition_size),
-          image_size)
-      # Checks min_partition_size (round to BLOCK_SIZE) is the minimum.
-      self.assertLess(
-          _SizeCalculator(min_partition_size - BLOCK_SIZE),
-          image_size)
-
-  def test_AVBCalcMinPartitionSize_FasterGrowthFooterSize(self):
-    """Tests with footer size which grows faster than partition size."""
-
-    def _SizeCalculator(partition_size):
-      """Max image size is the power of 0.95 of partition size."""
-      # Max image size grows less than partition size, which means
-      # footer size grows faster than partition size.
-      return int(math.pow(partition_size, 0.95))
-
-    for image_size in self._image_sizes:
-      min_partition_size = AVBCalcMinPartitionSize(image_size, _SizeCalculator)
-      # Checks min_partition_size can accommodate image_size.
-      self.assertGreaterEqual(
-          _SizeCalculator(min_partition_size),
-          image_size)
-      # Checks min_partition_size (round to BLOCK_SIZE) is the minimum.
-      self.assertLess(
-          _SizeCalculator(min_partition_size - BLOCK_SIZE),
-          image_size)
diff --git a/tools/releasetools/test_common.py b/tools/releasetools/test_common.py
index ec86eb2..c99049a 100644
--- a/tools/releasetools/test_common.py
+++ b/tools/releasetools/test_common.py
@@ -19,7 +19,6 @@
 import subprocess
 import tempfile
 import time
-import unittest
 import zipfile
 from hashlib import sha1
 
@@ -44,7 +43,8 @@
     yield '\0' * (step_size - block_size)
 
 
-class CommonZipTest(unittest.TestCase):
+class CommonZipTest(test_utils.ReleaseToolsTestCase):
+
   def _verify(self, zip_file, zip_file_name, arcname, expected_hash,
               test_file_name=None, expected_stat=None, expected_mode=0o644,
               expected_compress_type=zipfile.ZIP_STORED):
@@ -359,7 +359,7 @@
       os.remove(zip_file.name)
 
 
-class CommonApkUtilsTest(unittest.TestCase):
+class CommonApkUtilsTest(test_utils.ReleaseToolsTestCase):
   """Tests the APK utils related functions."""
 
   APKCERTS_TXT1 = (
@@ -407,9 +407,6 @@
   def setUp(self):
     self.testdata_dir = test_utils.get_testdata_dir()
 
-  def tearDown(self):
-    common.Cleanup()
-
   @staticmethod
   def _write_apkcerts_txt(apkcerts_txt, additional=None):
     if additional is None:
@@ -523,14 +520,11 @@
         {})
 
 
-class CommonUtilsTest(unittest.TestCase):
+class CommonUtilsTest(test_utils.ReleaseToolsTestCase):
 
   def setUp(self):
     self.testdata_dir = test_utils.get_testdata_dir()
 
-  def tearDown(self):
-    common.Cleanup()
-
   def test_GetSparseImage_emptyBlockMapFile(self):
     target_files = common.MakeTempFile(prefix='target_files-', suffix='.zip')
     with zipfile.ZipFile(target_files, 'w') as target_files_zip:
@@ -935,7 +929,7 @@
           AssertionError, common.LoadInfoDict, target_files_zip, True)
 
 
-class InstallRecoveryScriptFormatTest(unittest.TestCase):
+class InstallRecoveryScriptFormatTest(test_utils.ReleaseToolsTestCase):
   """Checks the format of install-recovery.sh.
 
   Its format should match between common.py and validate_target_files.py.
@@ -994,6 +988,3 @@
                              recovery_image, boot_image, self._info)
     validate_target_files.ValidateInstallRecoveryScript(self._tempdir,
                                                         self._info)
-
-  def tearDown(self):
-    common.Cleanup()
diff --git a/tools/releasetools/test_ota_from_target_files.py b/tools/releasetools/test_ota_from_target_files.py
index 29e0d83..f75b3a7 100644
--- a/tools/releasetools/test_ota_from_target_files.py
+++ b/tools/releasetools/test_ota_from_target_files.py
@@ -17,7 +17,6 @@
 import copy
 import os
 import os.path
-import unittest
 import zipfile
 
 import common
@@ -104,7 +103,7 @@
     self.script.append(('AssertSomeThumbprint',) + args)
 
 
-class BuildInfoTest(unittest.TestCase):
+class BuildInfoTest(test_utils.ReleaseToolsTestCase):
 
   TEST_INFO_DICT = {
       'build.prop' : {
@@ -352,10 +351,7 @@
         script_writer.script)
 
 
-class LoadOemDictsTest(unittest.TestCase):
-
-  def tearDown(self):
-    common.Cleanup()
+class LoadOemDictsTest(test_utils.ReleaseToolsTestCase):
 
   def test_NoneDict(self):
     self.assertIsNone(_LoadOemDicts(None))
@@ -388,7 +384,7 @@
       self.assertEqual('{}'.format(i), oem_dict['ro.build.index'])
 
 
-class OtaFromTargetFilesTest(unittest.TestCase):
+class OtaFromTargetFilesTest(test_utils.ReleaseToolsTestCase):
 
   TEST_TARGET_INFO_DICT = {
       'build.prop' : {
@@ -430,9 +426,6 @@
     common.OPTIONS.search_path = test_utils.get_search_path()
     self.assertIsNotNone(common.OPTIONS.search_path)
 
-  def tearDown(self):
-    common.Cleanup()
-
   def test_GetPackageMetadata_abOta_full(self):
     target_info_dict = copy.deepcopy(self.TEST_TARGET_INFO_DICT)
     target_info_dict['ab_update'] = 'true'
@@ -720,14 +713,11 @@
     )
 
 
-class PropertyFilesTest(unittest.TestCase):
+class PropertyFilesTest(test_utils.ReleaseToolsTestCase):
 
   def setUp(self):
     common.OPTIONS.no_signing = False
 
-  def tearDown(self):
-    common.Cleanup()
-
   @staticmethod
   def construct_zip_package(entries):
     zip_file = common.MakeTempFile(suffix='.zip')
@@ -1151,7 +1141,7 @@
       property_files.Verify(zip_fp, raw_metadata)
 
 
-class PayloadSignerTest(unittest.TestCase):
+class PayloadSignerTest(test_utils.ReleaseToolsTestCase):
 
   SIGFILE = 'sigfile.bin'
   SIGNED_SIGFILE = 'signed-sigfile.bin'
@@ -1167,9 +1157,6 @@
         common.OPTIONS.package_key : None,
     }
 
-  def tearDown(self):
-    common.Cleanup()
-
   def _assertFilesEqual(self, file1, file2):
     with open(file1, 'rb') as fp1, open(file2, 'rb') as fp2:
       self.assertEqual(fp1.read(), fp2.read())
@@ -1230,7 +1217,7 @@
     self._assertFilesEqual(verify_file, signed_file)
 
 
-class PayloadTest(unittest.TestCase):
+class PayloadTest(test_utils.ReleaseToolsTestCase):
 
   def setUp(self):
     self.testdata_dir = test_utils.get_testdata_dir()
@@ -1244,9 +1231,6 @@
         common.OPTIONS.package_key : None,
     }
 
-  def tearDown(self):
-    common.Cleanup()
-
   @staticmethod
   def _create_payload_full(secondary=False):
     target_file = construct_target_files(secondary)
diff --git a/tools/releasetools/test_rangelib.py b/tools/releasetools/test_rangelib.py
index e181187..1251e11 100644
--- a/tools/releasetools/test_rangelib.py
+++ b/tools/releasetools/test_rangelib.py
@@ -14,11 +14,11 @@
 # limitations under the License.
 #
 
-import unittest
-
 from rangelib import RangeSet
+from test_utils import ReleaseToolsTestCase
 
-class RangeSetTest(unittest.TestCase):
+
+class RangeSetTest(ReleaseToolsTestCase):
 
   def test_union(self):
     self.assertEqual(RangeSet("10-19 30-34").union(RangeSet("18-29")),
@@ -129,8 +129,8 @@
     self.assertEqual(
         RangeSet.parse_raw(RangeSet("0-9").to_string_raw()),
         RangeSet("0-9"))
-    self.assertEqual(RangeSet.parse_raw(
-        RangeSet("2-10 12").to_string_raw()),
+    self.assertEqual(
+        RangeSet.parse_raw(RangeSet("2-10 12").to_string_raw()),
         RangeSet("2-10 12"))
     self.assertEqual(
         RangeSet.parse_raw(RangeSet("11 2-10 12 1 0").to_string_raw()),
diff --git a/tools/releasetools/test_sign_target_files_apks.py b/tools/releasetools/test_sign_target_files_apks.py
index ac1b567..18762ee 100644
--- a/tools/releasetools/test_sign_target_files_apks.py
+++ b/tools/releasetools/test_sign_target_files_apks.py
@@ -14,11 +14,8 @@
 # limitations under the License.
 #
 
-from __future__ import print_function
-
 import base64
 import os.path
-import unittest
 import zipfile
 
 import common
@@ -28,7 +25,7 @@
     ReplaceVerityKeyId, RewriteProps)
 
 
-class SignTargetFilesApksTest(unittest.TestCase):
+class SignTargetFilesApksTest(test_utils.ReleaseToolsTestCase):
 
   MAC_PERMISSIONS_XML = """<?xml version="1.0" encoding="iso-8859-1"?>
 <policy>
@@ -39,9 +36,6 @@
   def setUp(self):
     self.testdata_dir = test_utils.get_testdata_dir()
 
-  def tearDown(self):
-    common.Cleanup()
-
   def test_EditTags(self):
     self.assertEqual(EditTags('dev-keys'), ('release-keys'))
     self.assertEqual(EditTags('test-keys'), ('release-keys'))
diff --git a/tools/releasetools/test_utils.py b/tools/releasetools/test_utils.py
index a15ff5b..b9c8dc7 100644
--- a/tools/releasetools/test_utils.py
+++ b/tools/releasetools/test_utils.py
@@ -21,6 +21,7 @@
 import os
 import os.path
 import struct
+import unittest
 
 import common
 
@@ -110,3 +111,10 @@
         fp.write(os.urandom(data_size))
 
   return sparse_image
+
+
+class ReleaseToolsTestCase(unittest.TestCase):
+  """A common base class for all the releasetools unittests."""
+
+  def tearDown(self):
+    common.Cleanup()
diff --git a/tools/releasetools/test_validate_target_files.py b/tools/releasetools/test_validate_target_files.py
index ecb7fde..d778d11 100644
--- a/tools/releasetools/test_validate_target_files.py
+++ b/tools/releasetools/test_validate_target_files.py
@@ -16,27 +16,21 @@
 
 """Unittests for validate_target_files.py."""
 
-from __future__ import print_function
-
 import os
 import os.path
 import shutil
-import unittest
 
-import build_image
 import common
 import test_utils
+import verity_utils
 from validate_target_files import ValidateVerifiedBootImages
 
 
-class ValidateTargetFilesTest(unittest.TestCase):
+class ValidateTargetFilesTest(test_utils.ReleaseToolsTestCase):
 
   def setUp(self):
     self.testdata_dir = test_utils.get_testdata_dir()
 
-  def tearDown(self):
-    common.Cleanup()
-
   def _generate_boot_image(self, output_file):
     kernel = common.MakeTempFile(prefix='kernel-')
     with open(kernel, 'wb') as kernel_fp:
@@ -115,7 +109,7 @@
   def _generate_system_image(self, output_file):
     verity_fec = True
     partition_size = 1024 * 1024
-    image_size, verity_size = build_image.AdjustPartitionSizeForVerity(
+    image_size, verity_size = verity_utils.AdjustPartitionSizeForVerity(
         partition_size, verity_fec)
 
     # Use an empty root directory.
@@ -138,7 +132,7 @@
         'verity_signer_cmd' : 'verity_signer',
         'verity_size' : str(verity_size),
     }
-    build_image.MakeVerityEnabledImage(output_file, verity_fec, prop_dict)
+    verity_utils.MakeVerityEnabledImage(output_file, verity_fec, prop_dict)
 
   def test_ValidateVerifiedBootImages_systemImage(self):
     input_tmp = common.MakeTempDir()
diff --git a/tools/releasetools/test_verity_utils.py b/tools/releasetools/test_verity_utils.py
index f318b02..0988d8e 100644
--- a/tools/releasetools/test_verity_utils.py
+++ b/tools/releasetools/test_verity_utils.py
@@ -16,25 +16,24 @@
 
 """Unittests for verity_utils.py."""
 
-from __future__ import print_function
-
+import math
 import os.path
-import unittest
+import random
 
-import build_image
 import common
 import sparse_img
-import test_utils
 from rangelib import RangeSet
+from test_utils import get_testdata_dir, ReleaseToolsTestCase
 from verity_utils import (
-    CreateHashtreeInfoGenerator, HashtreeInfo,
+    AdjustPartitionSizeForVerity, AVBCalcMinPartitionSize, BLOCK_SIZE,
+    CreateHashtreeInfoGenerator, HashtreeInfo, MakeVerityEnabledImage,
     VerifiedBootVersion1HashtreeInfoGenerator)
 
 
-class VerifiedBootVersion1HashtreeInfoGeneratorTest(unittest.TestCase):
+class VerifiedBootVersion1HashtreeInfoGeneratorTest(ReleaseToolsTestCase):
 
   def setUp(self):
-    self.testdata_dir = test_utils.get_testdata_dir()
+    self.testdata_dir = get_testdata_dir()
 
     self.partition_size = 1024 * 1024
     self.prop_dict = {
@@ -50,9 +49,6 @@
     self.expected_root_hash = \
         "0b7c4565e87b1026e11fbab91c0bc29e185c847a5b44d40e6e86e461e8adf80d"
 
-  def tearDown(self):
-    common.Cleanup()
-
   def _create_simg(self, raw_data):
     output_file = common.MakeTempFile()
     raw_image = common.MakeTempFile()
@@ -68,7 +64,7 @@
 
   def _generate_image(self):
     partition_size = 1024 * 1024
-    adjusted_size, verity_size = build_image.AdjustPartitionSizeForVerity(
+    adjusted_size, verity_size = AdjustPartitionSizeForVerity(
         partition_size, True)
 
     raw_image = ""
@@ -86,7 +82,7 @@
         'verity_signer_cmd': 'verity_signer',
         'verity_size': str(verity_size),
     }
-    build_image.MakeVerityEnabledImage(output_file, True, prop_dict)
+    MakeVerityEnabledImage(output_file, True, prop_dict)
 
     return output_file
 
@@ -165,3 +161,62 @@
     self.assertEqual(self.hash_algorithm, info.hash_algorithm)
     self.assertEqual(self.fixed_salt, info.salt)
     self.assertEqual(self.expected_root_hash, info.root_hash)
+
+
+class VerityUtilsTest(ReleaseToolsTestCase):
+
+  def setUp(self):
+    # To test AVBCalcMinPartitionSize(), by using 200MB to 2GB image size.
+    #   -  51200 = 200MB * 1024 * 1024 / 4096
+    #   - 524288 = 2GB * 1024 * 1024 * 1024 / 4096
+    self._image_sizes = [BLOCK_SIZE * random.randint(51200, 524288) + offset
+                         for offset in range(BLOCK_SIZE)]
+
+  def test_AVBCalcMinPartitionSize_LinearFooterSize(self):
+    """Tests with footer size which is linear to partition size."""
+    for image_size in self._image_sizes:
+      for ratio in 0.95, 0.56, 0.22:
+        expected_size = common.RoundUpTo4K(int(math.ceil(image_size / ratio)))
+        self.assertEqual(
+            expected_size,
+            AVBCalcMinPartitionSize(
+                image_size, lambda x, ratio=ratio: int(x * ratio)))
+
+  def test_AVBCalcMinPartitionSize_SlowerGrowthFooterSize(self):
+    """Tests with footer size which grows slower than partition size."""
+
+    def _SizeCalculator(partition_size):
+      """Footer size is the power of 0.95 of partition size."""
+      # Minus footer size to return max image size.
+      return partition_size - int(math.pow(partition_size, 0.95))
+
+    for image_size in self._image_sizes:
+      min_partition_size = AVBCalcMinPartitionSize(image_size, _SizeCalculator)
+      # Checks min_partition_size can accommodate image_size.
+      self.assertGreaterEqual(
+          _SizeCalculator(min_partition_size),
+          image_size)
+      # Checks min_partition_size (round to BLOCK_SIZE) is the minimum.
+      self.assertLess(
+          _SizeCalculator(min_partition_size - BLOCK_SIZE),
+          image_size)
+
+  def test_AVBCalcMinPartitionSize_FasterGrowthFooterSize(self):
+    """Tests with footer size which grows faster than partition size."""
+
+    def _SizeCalculator(partition_size):
+      """Max image size is the power of 0.95 of partition size."""
+      # Max image size grows less than partition size, which means
+      # footer size grows faster than partition size.
+      return int(math.pow(partition_size, 0.95))
+
+    for image_size in self._image_sizes:
+      min_partition_size = AVBCalcMinPartitionSize(image_size, _SizeCalculator)
+      # Checks min_partition_size can accommodate image_size.
+      self.assertGreaterEqual(
+          _SizeCalculator(min_partition_size),
+          image_size)
+      # Checks min_partition_size (round to BLOCK_SIZE) is the minimum.
+      self.assertLess(
+          _SizeCalculator(min_partition_size - BLOCK_SIZE),
+          image_size)
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."""