diff --git a/tools/sbom/generate-sbom.py b/tools/sbom/generate-sbom.py
new file mode 100755
index 0000000..0c5deb2
--- /dev/null
+++ b/tools/sbom/generate-sbom.py
@@ -0,0 +1,536 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2023 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.
+
+"""
+Generate the SBOM of the current target product in SPDX format.
+Usage example:
+  generate-sbom.py --output_file out/target/product/vsoc_x86_64/sbom.spdx \
+                   --metadata out/target/product/vsoc_x86_64/sbom-metadata.csv \
+                   --product_out_dir=out/target/product/vsoc_x86_64 \
+                   --build_version $(cat out/target/product/vsoc_x86_64/build_fingerprint.txt) \
+                   --product_mfr=Google
+"""
+
+import argparse
+import csv
+import datetime
+import google.protobuf.text_format as text_format
+import hashlib
+import os
+import metadata_file_pb2
+import sbom_data
+import sbom_writers
+
+
+# Package type
+PKG_SOURCE = 'SOURCE'
+PKG_UPSTREAM = 'UPSTREAM'
+PKG_PREBUILT = 'PREBUILT'
+
+# Security tag
+NVD_CPE23 = 'NVD-CPE2.3:'
+
+# Report
+ISSUE_NO_METADATA = 'No metadata generated in Make for installed files:'
+ISSUE_NO_METADATA_FILE = 'No METADATA file found for installed file:'
+ISSUE_METADATA_FILE_INCOMPLETE = 'METADATA file incomplete:'
+ISSUE_UNKNOWN_SECURITY_TAG_TYPE = 'Unknown security tag type:'
+ISSUE_INSTALLED_FILE_NOT_EXIST = 'Non-exist installed files:'
+INFO_METADATA_FOUND_FOR_PACKAGE = 'METADATA file found for packages:'
+
+
+def get_args():
+  parser = argparse.ArgumentParser()
+  parser.add_argument('-v', '--verbose', action='store_true', default=False, help='Print more information.')
+  parser.add_argument('--output_file', required=True, help='The generated SBOM file in SPDX format.')
+  parser.add_argument('--metadata', required=True, help='The SBOM metadata file path.')
+  parser.add_argument('--product_out_dir', required=True, help='The parent directory of all the installed files.')
+  parser.add_argument('--build_version', required=True, help='The build version.')
+  parser.add_argument('--product_mfr', required=True, help='The product manufacturer.')
+  parser.add_argument('--json', action='store_true', default=False, help='Generated SBOM file in SPDX JSON format')
+  parser.add_argument('--unbundled', action='store_true', default=False, help='Generate SBOM file for unbundled module')
+
+  return parser.parse_args()
+
+
+def log(*info):
+  if args.verbose:
+    for i in info:
+      print(i)
+
+
+def encode_for_spdxid(s):
+  """Simple encode for string values used in SPDXID which uses the charset of A-Za-Z0-9.-"""
+  result = ''
+  for c in s:
+    if c.isalnum() or c in '.-':
+      result += c
+    elif c in '_@/':
+      result += '-'
+    else:
+      result += '0x' + c.encode('utf-8').hex()
+
+  return result.lstrip('-')
+
+
+def new_package_id(package_name, type):
+  return f'SPDXRef-{type}-{encode_for_spdxid(package_name)}'
+
+
+def new_file_id(file_path):
+  return f'SPDXRef-{encode_for_spdxid(file_path)}'
+
+
+def checksum(file_path):
+  file_path = args.product_out_dir + '/' + file_path
+  h = hashlib.sha1()
+  if os.path.islink(file_path):
+    h.update(os.readlink(file_path).encode('utf-8'))
+  else:
+    with open(file_path, 'rb') as f:
+      h.update(f.read())
+  return f'SHA1: {h.hexdigest()}'
+
+
+def is_soong_prebuilt_module(file_metadata):
+  return file_metadata['soong_module_type'] and file_metadata['soong_module_type'] in [
+      'android_app_import', 'android_library_import', 'cc_prebuilt_binary', 'cc_prebuilt_library',
+      'cc_prebuilt_library_headers', 'cc_prebuilt_library_shared', 'cc_prebuilt_library_static', 'cc_prebuilt_object',
+      'dex_import', 'java_import', 'java_sdk_library_import', 'java_system_modules_import',
+      'libclang_rt_prebuilt_library_static', 'libclang_rt_prebuilt_library_shared', 'llvm_prebuilt_library_static',
+      'ndk_prebuilt_object', 'ndk_prebuilt_shared_stl', 'nkd_prebuilt_static_stl', 'prebuilt_apex',
+      'prebuilt_bootclasspath_fragment', 'prebuilt_dsp', 'prebuilt_firmware', 'prebuilt_kernel_modules',
+      'prebuilt_rfsa', 'prebuilt_root', 'rust_prebuilt_dylib', 'rust_prebuilt_library', 'rust_prebuilt_rlib',
+      'vndk_prebuilt_shared',
+
+      # 'android_test_import',
+      # 'cc_prebuilt_test_library_shared',
+      # 'java_import_host',
+      # 'java_test_import',
+      # 'llvm_host_prebuilt_library_shared',
+      # 'prebuilt_apis',
+      # 'prebuilt_build_tool',
+      # 'prebuilt_defaults',
+      # 'prebuilt_etc',
+      # 'prebuilt_etc_host',
+      # 'prebuilt_etc_xml',
+      # 'prebuilt_font',
+      # 'prebuilt_hidl_interfaces',
+      # 'prebuilt_platform_compat_config',
+      # 'prebuilt_stubs_sources',
+      # 'prebuilt_usr_share',
+      # 'prebuilt_usr_share_host',
+      # 'soong_config_module_type_import',
+  ]
+
+
+def is_source_package(file_metadata):
+  module_path = file_metadata['module_path']
+  return module_path.startswith('external/') and not is_prebuilt_package(file_metadata)
+
+
+def is_prebuilt_package(file_metadata):
+  module_path = file_metadata['module_path']
+  if module_path:
+    return (module_path.startswith('prebuilts/') or
+            is_soong_prebuilt_module(file_metadata) or
+            file_metadata['is_prebuilt_make_module'])
+
+  kernel_module_copy_files = file_metadata['kernel_module_copy_files']
+  if kernel_module_copy_files and not kernel_module_copy_files.startswith('ANDROID-GEN:'):
+    return True
+
+  return False
+
+
+def get_source_package_info(file_metadata, metadata_file_path):
+  """Return source package info exists in its METADATA file, currently including name, security tag
+  and external SBOM reference.
+
+  See go/android-spdx and go/android-sbom-gen for more details.
+  """
+  if not metadata_file_path:
+    return file_metadata['module_path'], []
+
+  metadata_proto = metadata_file_protos[metadata_file_path]
+  external_refs = []
+  for tag in metadata_proto.third_party.security.tag:
+    if tag.lower().startswith((NVD_CPE23 + 'cpe:2.3:').lower()):
+      external_refs.append(
+        sbom_data.PackageExternalRef(category=sbom_data.PackageExternalRefCategory.SECURITY,
+                                     type=sbom_data.PackageExternalRefType.cpe23Type,
+                                     locator=tag.removeprefix(NVD_CPE23)))
+    elif tag.lower().startswith((NVD_CPE23 + 'cpe:/').lower()):
+      external_refs.append(
+        sbom_data.PackageExternalRef(category=sbom_data.PackageExternalRefCategory.SECURITY,
+                                     type=sbom_data.PackageExternalRefType.cpe22Type,
+                                     locator=tag.removeprefix(NVD_CPE23)))
+
+  if metadata_proto.name:
+    return metadata_proto.name, external_refs
+  else:
+    return os.path.basename(metadata_file_path), external_refs  # return the directory name only as package name
+
+
+def get_prebuilt_package_name(file_metadata, metadata_file_path):
+  """Return name of a prebuilt package, which can be from the METADATA file, metadata file path,
+  module path or kernel module's source path if the installed file is a kernel module.
+
+  See go/android-spdx and go/android-sbom-gen for more details.
+  """
+  name = None
+  if metadata_file_path:
+    metadata_proto = metadata_file_protos[metadata_file_path]
+    if metadata_proto.name:
+      name = metadata_proto.name
+    else:
+      name = metadata_file_path
+  elif file_metadata['module_path']:
+    name = file_metadata['module_path']
+  elif file_metadata['kernel_module_copy_files']:
+    src_path = file_metadata['kernel_module_copy_files'].split(':')[0]
+    name = os.path.dirname(src_path)
+
+  return name.removeprefix('prebuilts/').replace('/', '-')
+
+
+def get_metadata_file_path(file_metadata):
+  """Search for METADATA file of a package and return its path."""
+  metadata_path = ''
+  if file_metadata['module_path']:
+    metadata_path = file_metadata['module_path']
+  elif file_metadata['kernel_module_copy_files']:
+    metadata_path = os.path.dirname(file_metadata['kernel_module_copy_files'].split(':')[0])
+
+  while metadata_path and not os.path.exists(metadata_path + '/METADATA'):
+    metadata_path = os.path.dirname(metadata_path)
+
+  return metadata_path
+
+
+def get_package_version(metadata_file_path):
+  """Return a package's version in its METADATA file."""
+  if not metadata_file_path:
+    return None
+  metadata_proto = metadata_file_protos[metadata_file_path]
+  return metadata_proto.third_party.version
+
+
+def get_package_homepage(metadata_file_path):
+  """Return a package's homepage URL in its METADATA file."""
+  if not metadata_file_path:
+    return None
+  metadata_proto = metadata_file_protos[metadata_file_path]
+  if metadata_proto.third_party.homepage:
+    return metadata_proto.third_party.homepage
+  for url in metadata_proto.third_party.url:
+    if url.type == metadata_file_pb2.URL.Type.HOMEPAGE:
+      return url.value
+
+  return None
+
+
+def get_package_download_location(metadata_file_path):
+  """Return a package's code repository URL in its METADATA file."""
+  if not metadata_file_path:
+    return None
+  metadata_proto = metadata_file_protos[metadata_file_path]
+  if metadata_proto.third_party.url:
+    urls = sorted(metadata_proto.third_party.url, key=lambda url: url.type)
+    if urls[0].type != metadata_file_pb2.URL.Type.HOMEPAGE:
+      return urls[0].value
+    elif len(urls) > 1:
+      return urls[1].value
+
+  return None
+
+
+def get_sbom_fragments(installed_file_metadata, metadata_file_path):
+  """Return SPDX fragment of source/prebuilt packages, which usually contains a SOURCE/PREBUILT
+  package, a UPSTREAM package if it's a source package and a external SBOM document reference if
+  it's a prebuilt package with sbom_ref defined in its METADATA file.
+
+  See go/android-spdx and go/android-sbom-gen for more details.
+  """
+  external_doc_ref = None
+  packages = []
+  relationships = []
+
+  # Info from METADATA file
+  homepage = get_package_homepage(metadata_file_path)
+  version = get_package_version(metadata_file_path)
+  download_location = get_package_download_location(metadata_file_path)
+
+  if is_source_package(installed_file_metadata):
+    # Source fork packages
+    name, external_refs = get_source_package_info(installed_file_metadata, metadata_file_path)
+    source_package_id = new_package_id(name, PKG_SOURCE)
+    source_package = sbom_data.Package(id=source_package_id, name=name, version=args.build_version,
+                                       supplier='Organization: ' + args.product_mfr,
+                                       external_refs=external_refs)
+
+    upstream_package_id = new_package_id(name, PKG_UPSTREAM)
+    upstream_package = sbom_data.Package(id=upstream_package_id, name=name, version=version,
+                                         supplier='Organization: ' + homepage if homepage else None,
+                                         download_location=download_location)
+    packages += [source_package, upstream_package]
+    relationships.append(sbom_data.Relationship(id1=source_package_id,
+                                                relationship=sbom_data.RelationshipType.VARIANT_OF,
+                                                id2=upstream_package_id))
+  elif is_prebuilt_package(installed_file_metadata):
+    # Prebuilt fork packages
+    name = get_prebuilt_package_name(installed_file_metadata, metadata_file_path)
+    prebuilt_package_id = new_package_id(name, PKG_PREBUILT)
+    prebuilt_package = sbom_data.Package(id=prebuilt_package_id,
+                                         name=name,
+                                         version=args.build_version,
+                                         supplier='Organization: ' + args.product_mfr)
+    packages.append(prebuilt_package)
+
+    if metadata_file_path:
+      metadata_proto = metadata_file_protos[metadata_file_path]
+      if metadata_proto.third_party.WhichOneof('sbom') == 'sbom_ref':
+        sbom_url = metadata_proto.third_party.sbom_ref.url
+        sbom_checksum = metadata_proto.third_party.sbom_ref.checksum
+        upstream_element_id = metadata_proto.third_party.sbom_ref.element_id
+        if sbom_url and sbom_checksum and upstream_element_id:
+          doc_ref_id = f'DocumentRef-{PKG_UPSTREAM}-{encode_for_spdxid(name)}'
+          external_doc_ref = sbom_data.DocumentExternalReference(id=doc_ref_id,
+                                                                 uri=sbom_url,
+                                                                 checksum=sbom_checksum)
+          relationships.append(
+            sbom_data.Relationship(id1=prebuilt_package_id,
+                                   relationship=sbom_data.RelationshipType.VARIANT_OF,
+                                   id2=doc_ref_id + ':' + upstream_element_id))
+
+  return external_doc_ref, packages, relationships
+
+
+def generate_package_verification_code(files):
+  checksums = [file.checksum for file in files]
+  checksums.sort()
+  h = hashlib.sha1()
+  h.update(''.join(checksums).encode(encoding='utf-8'))
+  return h.hexdigest()
+
+
+def save_report(report):
+  prefix, _ = os.path.splitext(args.output_file)
+  with open(prefix + '-gen-report.txt', 'w', encoding='utf-8') as report_file:
+    for type, issues in report.items():
+      report_file.write(type + '\n')
+      for issue in issues:
+        report_file.write('\t' + issue + '\n')
+      report_file.write('\n')
+
+
+# Validate the metadata generated by Make for installed files and report if there is no metadata.
+def installed_file_has_metadata(installed_file_metadata, report):
+  installed_file = installed_file_metadata['installed_file']
+  module_path = installed_file_metadata['module_path']
+  product_copy_files = installed_file_metadata['product_copy_files']
+  kernel_module_copy_files = installed_file_metadata['kernel_module_copy_files']
+  is_platform_generated = installed_file_metadata['is_platform_generated']
+
+  if (not module_path and
+      not product_copy_files and
+      not kernel_module_copy_files and
+      not is_platform_generated and
+      not installed_file.endswith('.fsv_meta')):
+    report[ISSUE_NO_METADATA].append(installed_file)
+    return False
+
+  return True
+
+
+def report_metadata_file(metadata_file_path, installed_file_metadata, report):
+  if metadata_file_path:
+    report[INFO_METADATA_FOUND_FOR_PACKAGE].append(
+        'installed_file: {}, module_path: {}, METADATA file: {}'.format(
+            installed_file_metadata['installed_file'],
+            installed_file_metadata['module_path'],
+            metadata_file_path + '/METADATA'))
+
+    package_metadata = metadata_file_pb2.Metadata()
+    with open(metadata_file_path + '/METADATA', 'rt') as f:
+      text_format.Parse(f.read(), package_metadata)
+
+    if not metadata_file_path in metadata_file_protos:
+      metadata_file_protos[metadata_file_path] = package_metadata
+      if not package_metadata.name:
+        report[ISSUE_METADATA_FILE_INCOMPLETE].append(f'{metadata_file_path}/METADATA does not has "name"')
+
+      if not package_metadata.third_party.version:
+        report[ISSUE_METADATA_FILE_INCOMPLETE].append(
+            f'{metadata_file_path}/METADATA does not has "third_party.version"')
+
+      for tag in package_metadata.third_party.security.tag:
+        if not tag.startswith(NVD_CPE23):
+          report[ISSUE_UNKNOWN_SECURITY_TAG_TYPE].append(
+              f'Unknown security tag type: {tag} in {metadata_file_path}/METADATA')
+  else:
+    report[ISSUE_NO_METADATA_FILE].append(
+        "installed_file: {}, module_path: {}".format(
+            installed_file_metadata['installed_file'], installed_file_metadata['module_path']))
+
+
+def generate_sbom_for_unbundled():
+  with open(args.metadata, newline='') as sbom_metadata_file:
+    reader = csv.DictReader(sbom_metadata_file)
+    doc = sbom_data.Document(name=args.build_version,
+                             namespace=f'https://www.google.com/sbom/spdx/android/{args.build_version}',
+                             creators=['Organization: ' + args.product_mfr])
+    for installed_file_metadata in reader:
+      installed_file = installed_file_metadata['installed_file']
+      if args.output_file != args.product_out_dir + installed_file + ".spdx":
+        continue
+
+      module_path = installed_file_metadata['module_path']
+      package_id = new_package_id(module_path, PKG_PREBUILT)
+      package = sbom_data.Package(id=package_id,
+                                  name=module_path,
+                                  version=args.build_version,
+                                  supplier='Organization: ' + args.product_mfr)
+      file_id = new_file_id(installed_file)
+      file = sbom_data.File(id=file_id, name=installed_file, checksum=checksum(installed_file))
+      relationship = sbom_data.Relationship(id1=file_id,
+                                            relationship=sbom_data.RelationshipType.GENERATED_FROM,
+                                            id2=package_id)
+      doc.add_package(package)
+      doc.files.append(file)
+      doc.describes = file_id
+      doc.add_relationship(relationship)
+      doc.created = datetime.datetime.now(tz=datetime.timezone.utc).strftime('%Y-%m-%dT%H:%M:%SZ')
+      break
+
+  with open(args.output_file, 'w', encoding="utf-8") as file:
+    sbom_writers.TagValueWriter.write(doc, file, fragment=True)
+
+
+def main():
+  global args
+  args = get_args()
+  log('Args:', vars(args))
+
+  if args.unbundled:
+    generate_sbom_for_unbundled()
+    return
+
+  global metadata_file_protos
+  metadata_file_protos = {}
+
+  doc = sbom_data.Document(name=args.build_version,
+                           namespace=f'https://www.google.com/sbom/spdx/android/{args.build_version}',
+                           creators=['Organization: ' + args.product_mfr])
+
+  product_package = sbom_data.Package(id=sbom_data.SPDXID_PRODUCT,
+                                      name=sbom_data.PACKAGE_NAME_PRODUCT,
+                                      version=args.build_version,
+                                      supplier='Organization: ' + args.product_mfr,
+                                      files_analyzed=True)
+  doc.packages.append(product_package)
+
+  doc.packages.append(sbom_data.Package(id=sbom_data.SPDXID_PLATFORM,
+                                        name=sbom_data.PACKAGE_NAME_PLATFORM,
+                                        version=args.build_version,
+                                        supplier='Organization: ' + args.product_mfr))
+
+  # Report on some issues and information
+  report = {
+    ISSUE_NO_METADATA: [],
+    ISSUE_NO_METADATA_FILE: [],
+    ISSUE_METADATA_FILE_INCOMPLETE: [],
+    ISSUE_UNKNOWN_SECURITY_TAG_TYPE: [],
+    ISSUE_INSTALLED_FILE_NOT_EXIST: [],
+    INFO_METADATA_FOUND_FOR_PACKAGE: [],
+  }
+
+  # Scan the metadata in CSV file and create the corresponding package and file records in SPDX
+  with open(args.metadata, newline='') as sbom_metadata_file:
+    reader = csv.DictReader(sbom_metadata_file)
+    for installed_file_metadata in reader:
+      installed_file = installed_file_metadata['installed_file']
+      module_path = installed_file_metadata['module_path']
+      product_copy_files = installed_file_metadata['product_copy_files']
+      kernel_module_copy_files = installed_file_metadata['kernel_module_copy_files']
+
+      if not installed_file_has_metadata(installed_file_metadata, report):
+        continue
+      file_path = args.product_out_dir + '/' + installed_file
+      if not (os.path.islink(file_path) or os.path.isfile(file_path)):
+        report[ISSUE_INSTALLED_FILE_NOT_EXIST].append(installed_file)
+        continue
+
+      file_id = new_file_id(installed_file)
+      doc.files.append(
+        sbom_data.File(id=file_id, name=installed_file, checksum=checksum(installed_file)))
+      product_package.file_ids.append(file_id)
+
+      if is_source_package(installed_file_metadata) or is_prebuilt_package(installed_file_metadata):
+        metadata_file_path = get_metadata_file_path(installed_file_metadata)
+        report_metadata_file(metadata_file_path, installed_file_metadata, report)
+
+        # File from source fork packages or prebuilt fork packages
+        external_doc_ref, pkgs, rels = get_sbom_fragments(installed_file_metadata, metadata_file_path)
+        if len(pkgs) > 0:
+          if external_doc_ref:
+            doc.add_external_ref(external_doc_ref)
+          for p in pkgs:
+            doc.add_package(p)
+          for rel in rels:
+            doc.add_relationship(rel)
+          fork_package_id = pkgs[0].id  # The first package should be the source/prebuilt fork package
+          doc.add_relationship(sbom_data.Relationship(id1=file_id,
+                                                      relationship=sbom_data.RelationshipType.GENERATED_FROM,
+                                                      id2=fork_package_id))
+      elif module_path or installed_file_metadata['is_platform_generated']:
+        # File from PLATFORM package
+        doc.add_relationship(sbom_data.Relationship(id1=file_id,
+                                                    relationship=sbom_data.RelationshipType.GENERATED_FROM,
+                                                    id2=sbom_data.SPDXID_PLATFORM))
+      elif product_copy_files:
+        # Format of product_copy_files: <source path>:<dest path>
+        src_path = product_copy_files.split(':')[0]
+        # So far product_copy_files are copied from directory system, kernel, hardware, frameworks and device,
+        # so process them as files from PLATFORM package
+        doc.add_relationship(sbom_data.Relationship(id1=file_id,
+                                                    relationship=sbom_data.RelationshipType.GENERATED_FROM,
+                                                    id2=sbom_data.SPDXID_PLATFORM))
+      elif installed_file.endswith('.fsv_meta'):
+        # See build/make/core/Makefile:2988
+        doc.add_relationship(sbom_data.Relationship(id1=file_id,
+                                                    relationship=sbom_data.RelationshipType.GENERATED_FROM,
+                                                    id2=sbom_data.SPDXID_PLATFORM))
+      elif kernel_module_copy_files.startswith('ANDROID-GEN'):
+        # For the four files generated for _dlkm, _ramdisk partitions
+        # See build/make/core/Makefile:323
+        doc.add_relationship(sbom_data.Relationship(id1=file_id,
+                                                    relationship=sbom_data.RelationshipType.GENERATED_FROM,
+                                                    id2=sbom_data.SPDXID_PLATFORM))
+
+  product_package.verification_code = generate_package_verification_code(doc.files)
+
+  # Save SBOM records to output file
+  doc.created = datetime.datetime.now(tz=datetime.timezone.utc).strftime('%Y-%m-%dT%H:%M:%SZ')
+  with open(args.output_file, 'w', encoding="utf-8") as file:
+    sbom_writers.TagValueWriter.write(doc, file)
+  if args.json:
+    with open(args.output_file+'.json', 'w', encoding="utf-8") as file:
+      sbom_writers.JSONWriter.write(doc, file)
+
+
+if __name__ == '__main__':
+  main()