diff --git a/tools/releasetools/apex_utils.py b/tools/releasetools/apex_utils.py
new file mode 100644
index 0000000..d14c94f
--- /dev/null
+++ b/tools/releasetools/apex_utils.py
@@ -0,0 +1,147 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2019 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+import os.path
+import re
+import shlex
+import sys
+
+import common
+
+logger = logging.getLogger(__name__)
+
+
+class ApexInfoError(Exception):
+  """An Exception raised during Apex Information command."""
+
+  def __init__(self, message):
+    Exception.__init__(self, message)
+
+
+class ApexSigningError(Exception):
+  """An Exception raised during Apex Payload signing."""
+
+  def __init__(self, message):
+    Exception.__init__(self, message)
+
+
+def SignApexPayload(payload_file, payload_key_path, payload_key_name, algorithm,
+                    salt, signing_args=None):
+  """Signs a given payload_file with the payload key."""
+  # Add the new footer. Old footer, if any, will be replaced by avbtool.
+  cmd = ['avbtool', 'add_hashtree_footer',
+         '--do_not_generate_fec',
+         '--algorithm', algorithm,
+         '--key', payload_key_path,
+         '--prop', 'apex.key:{}'.format(payload_key_name),
+         '--image', payload_file,
+         '--salt', salt]
+  if signing_args:
+    cmd.extend(shlex.split(signing_args))
+
+  try:
+    common.RunAndCheckOutput(cmd)
+  except common.ExternalError as e:
+    raise ApexSigningError, \
+        'Failed to sign APEX payload {} with {}:\n{}'.format(
+            payload_file, payload_key_path, e), sys.exc_info()[2]
+
+  # Verify the signed payload image with specified public key.
+  logger.info('Verifying %s', payload_file)
+  VerifyApexPayload(payload_file, payload_key_path)
+
+
+def VerifyApexPayload(payload_file, payload_key):
+  """Verifies the APEX payload signature with the given key."""
+  cmd = ['avbtool', 'verify_image', '--image', payload_file,
+         '--key', payload_key]
+  try:
+    common.RunAndCheckOutput(cmd)
+  except common.ExternalError as e:
+    raise ApexSigningError, \
+        'Failed to validate payload signing for {} with {}:\n{}'.format(
+            payload_file, payload_key, e), sys.exc_info()[2]
+
+
+def ParseApexPayloadInfo(payload_path):
+  """Parses the APEX payload info.
+
+  Args:
+    payload_path: The path to the payload image.
+
+  Raises:
+    ApexInfoError on parsing errors.
+
+  Returns:
+    A dict that contains payload property-value pairs. The dict should at least
+    contain Algorithm, Salt and apex.key.
+  """
+  if not os.path.exists(payload_path):
+    raise ApexInfoError('Failed to find image: {}'.format(payload_path))
+
+  cmd = ['avbtool', 'info_image', '--image', payload_path]
+  try:
+    output = common.RunAndCheckOutput(cmd)
+  except common.ExternalError as e:
+    raise ApexInfoError, \
+        'Failed to get APEX payload info for {}:\n{}'.format(
+            payload_path, e), sys.exc_info()[2]
+
+  # Extract the Algorithm / Salt / Prop info from payload (i.e. an image signed
+  # with avbtool). For example,
+  # Algorithm:                SHA256_RSA4096
+  PAYLOAD_INFO_PATTERN = (
+      r'^\s*(?P<key>Algorithm|Salt|Prop)\:\s*(?P<value>.*?)$')
+  payload_info_matcher = re.compile(PAYLOAD_INFO_PATTERN)
+
+  payload_info = {}
+  for line in output.split('\n'):
+    line_info = payload_info_matcher.match(line)
+    if not line_info:
+      continue
+
+    key, value = line_info.group('key'), line_info.group('value')
+
+    if key == 'Prop':
+      # Further extract the property key-value pair, from a 'Prop:' line. For
+      # example,
+      #   Prop: apex.key -> 'com.android.runtime'
+      # Note that avbtool writes single or double quotes around values.
+      PROPERTY_DESCRIPTOR_PATTERN = r'^\s*(?P<key>.*?)\s->\s*(?P<value>.*?)$'
+
+      prop_matcher = re.compile(PROPERTY_DESCRIPTOR_PATTERN)
+      prop = prop_matcher.match(value)
+      if not prop:
+        raise ApexInfoError(
+            'Failed to parse prop string {}'.format(value))
+
+      prop_key, prop_value = prop.group('key'), prop.group('value')
+      if prop_key == 'apex.key':
+        # avbtool dumps the prop value with repr(), which contains single /
+        # double quotes that we don't want.
+        payload_info[prop_key] = prop_value.strip('\"\'')
+
+    else:
+      payload_info[key] = value
+
+  # Sanity check.
+  for key in ('Algorithm', 'Salt', 'apex.key'):
+    if key not in payload_info:
+      raise ApexInfoError(
+          'Failed to find {} prop in {}'.format(key, payload_path))
+
+  return payload_info