gki/generate_gki_certificate.py

#!/usr/bin/env python3
#
# Copyright 2021, 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 a Generic Boot Image certificate suitable for VTS verification."""

from argparse import ArgumentParser
import subprocess


def generate_gki_certificate(image, avbtool, name, algorithm, key, salt,
                             additional_avb_args, output):
    """Shell out to avbtool to generate a GKI certificate."""

    # Need to specify a value of --partition_size for avbtool to work.
    # We use 64 MB below, but avbtool will not resize the boot image to
    # this size because --do_not_append_vbmeta_image is also specified.
    avbtool_cmd = [
        avbtool, 'add_hash_footer',
        '--partition_name', name,
        '--partition_size', str(64 * 1024 * 1024),
        '--image', image,
        '--algorithm', algorithm,
        '--key', key,
        '--do_not_append_vbmeta_image',
        '--output_vbmeta_image', output,
    ]

    if salt is not None:
        avbtool_cmd += ['--salt', salt]

    avbtool_cmd += additional_avb_args

    subprocess.check_call(avbtool_cmd)