Merge "Don't read through symlinks in fsverity_metadata_generator" into main

    out = subprocess.check_output(cmd, universal_newlines=True).strip()

    return bytes(bytearray.fromhex(out))

  def generate(self, input_file, output_file=None):

  def generate(self, input_file, output_file):

    if self._signature != 'none':

      if not self._key:

        raise RuntimeError("key must be specified.")

      if not self._cert:

        raise RuntimeError("cert must be specified.")

    if not output_file:

      output_file = input_file + '.fsv_meta'

    with TempDirectory() as temp_dir:

      self._do_generate(input_file, output_file, temp_dir)

      required=True)

  args = p.parse_args(sys.argv[1:])

  output_file = args.output

  if not output_file:

    output_file = input_file + '.fsv_meta'

  if output_file != args.input + '.fsv_meta':

    sys.exit('When generating .fsv_meta files for symlinks, we assume that all fsv_meta files '

      'are named the same as the file they protect, just with the .fsv_meta suffix appended. '

      'We require that all .fsv_meta files follow this convention regardless of if it\'s a link or '

      'not. However {args.input} had a different output file: {args.output}')

  if os.path.islink(args.input):

    target = os.readlink(args.input) + '.fsv_meta'

    os.symlink(target, output_file)

    sys.exit(0)

  generator = FSVerityMetadataGenerator(args.fsverity_path)

  generator.set_signature(args.signature)

  if args.signature == 'none':

    generator.set_cert(args.cert)

  generator.set_key_format(args.key_format)

  generator.set_hash_alg(args.hash_alg)

  generator.generate(args.input, args.output)

  generator.generate(args.input, output_file)