validate_target_files.py revision afaa0a638b901ff2b474214caa65f136421abbae 
1#!/usr/bin/env python
2
3# Copyright (C) 2017 The Android Open Source Project
4#
5# Licensed under the Apache License, Version 2.0 (the "License");
6# you may not use this file except in compliance with the License.
7# You may obtain a copy of the License at
8#
9#      http://www.apache.org/licenses/LICENSE-2.0
10#
11# Unless required by applicable law or agreed to in writing, software
12# distributed under the License is distributed on an "AS IS" BASIS,
13# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14# See the License for the specific language governing permissions and
15# limitations under the License.
16
17"""
18Validate a given (signed) target_files.zip.
19
20It performs checks to ensure the integrity of the input zip.
21 - It verifies the file consistency between the ones in IMAGES/system.img (read
22   via IMAGES/system.map) and the ones under unpacked folder of SYSTEM/. The
23   same check also applies to the vendor image if present.
24"""
25
26import common
27import logging
28import os.path
29import sparse_img
30import sys
31
32
33def _GetImage(which, tmpdir):
34  assert which in ('system', 'vendor')
35
36  path = os.path.join(tmpdir, 'IMAGES', which + '.img')
37  mappath = os.path.join(tmpdir, 'IMAGES', which + '.map')
38
39  # Map file must exist (allowed to be empty).
40  assert os.path.exists(path) and os.path.exists(mappath)
41
42  clobbered_blocks = '0'
43  return sparse_img.SparseImage(path, mappath, clobbered_blocks)
44
45
46def ValidateFileConsistency(input_zip, input_tmp):
47  """Compare the files from image files and unpacked folders."""
48
49  def RoundUpTo4K(value):
50    rounded_up = value + 4095
51    return rounded_up - (rounded_up % 4096)
52
53  def CheckAllFiles(which):
54    logging.info('Checking %s image.', which)
55    image = _GetImage(which, input_tmp)
56    prefix = '/' + which
57    for entry in image.file_map:
58      if not entry.startswith(prefix):
59        continue
60
61      # Read the blocks that the file resides. Note that it will contain the
62      # bytes past the file length, which is expected to be padded with '\0's.
63      ranges = image.file_map[entry]
64      blocks_sha1 = image.RangeSha1(ranges)
65
66      # The filename under unpacked directory, such as SYSTEM/bin/sh.
67      unpacked_name = os.path.join(
68          input_tmp, which.upper(), entry[(len(prefix) + 1):])
69      with open(unpacked_name) as f:
70        file_data = f.read()
71      file_size = len(file_data)
72      file_size_rounded_up = RoundUpTo4K(file_size)
73      file_data += '\0' * (file_size_rounded_up - file_size)
74      file_sha1 = common.File(entry, file_data).sha1
75
76      assert blocks_sha1 == file_sha1, \
77          'file: %s, range: %s, blocks_sha1: %s, file_sha1: %s' % (
78              entry, ranges, blocks_sha1, file_sha1)
79
80  logging.info('Validating file consistency.')
81
82  # Verify IMAGES/system.img.
83  CheckAllFiles('system')
84
85  # Verify IMAGES/vendor.img if applicable.
86  if 'VENDOR/' in input_zip.namelist():
87    CheckAllFiles('vendor')
88
89  # Not checking IMAGES/system_other.img since it doesn't have the map file.
90
91
92def main(argv):
93  def option_handler():
94    return True
95
96  args = common.ParseOptions(
97      argv, __doc__, extra_opts="",
98      extra_long_opts=[],
99      extra_option_handler=option_handler)
100
101  if len(args) != 1:
102    common.Usage(__doc__)
103    sys.exit(1)
104
105  logging_format = '%(asctime)s - %(filename)s - %(levelname)-8s: %(message)s'
106  date_format = '%Y/%m/%d %H:%M:%S'
107  logging.basicConfig(level=logging.INFO, format=logging_format,
108                      datefmt=date_format)
109
110  logging.info("Unzipping the input target_files.zip: %s", args[0])
111  input_tmp, input_zip = common.UnzipTemp(args[0])
112
113  ValidateFileConsistency(input_zip, input_tmp)
114
115  # TODO: Check if the OTA keys have been properly updated (the ones on /system,
116  # in recovery image).
117
118  # TODO(b/35411009): Verify the contents in /system/bin/install-recovery.sh.
119
120  logging.info("Done.")
121
122
123if __name__ == '__main__':
124  try:
125    main(sys.argv[1:])
126  finally:
127    common.Cleanup()
128