| # -*- coding: utf-8 -*- |
| # Copyright 2018 The Chromium OS Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| """Script to generate a Chromium OS update for use by the update engine. |
| |
| If a source .bin is specified, the update is assumed to be a delta update. |
| """ |
| |
| from __future__ import print_function |
| |
| import os |
| import shutil |
| import tempfile |
| |
| from chromite.lib import constants |
| from chromite.lib import commandline |
| from chromite.lib import cros_build_lib |
| from chromite.lib import cros_logging as logging |
| from chromite.lib import osutils |
| |
| |
| _DELTA_GENERATOR = 'delta_generator' |
| |
| |
| # TODO(tbrindus): move this to paygen/filelib.py. |
| def CopyFileSegment(in_file, in_mode, in_len, out_file, out_mode, in_seek=0): |
| """Simulates a `dd` operation with seeks.""" |
| with open(in_file, in_mode) as in_stream, \ |
| open(out_file, out_mode) as out_stream: |
| in_stream.seek(in_seek) |
| remaining = in_len |
| while remaining: |
| chunk = in_stream.read(min(8192 * 1024, remaining)) |
| remaining -= len(chunk) |
| out_stream.write(chunk) |
| |
| |
| # TODO(tbrindus): move this to paygen/filelib.py. |
| def ExtractPartitionToTempFile(filename, partition, temp_file=None): |
| """Extracts |partition| from |filename| into |temp_file|. |
| |
| If |temp_file| is not specified, an arbitrary file is used. |
| |
| Returns the location of the extracted partition. |
| """ |
| if temp_file is None: |
| temp_file = tempfile.mktemp(prefix='cros_generate_update_payload') |
| |
| parts = cros_build_lib.GetImageDiskPartitionInfo(filename) |
| part_info = parts[partition] |
| |
| offset = int(part_info.start) |
| length = int(part_info.size) |
| |
| CopyFileSegment(filename, 'r', length, temp_file, 'w', in_seek=offset) |
| |
| return temp_file |
| |
| |
| def PatchKernel(image, kern_file): |
| """Patches kernel |kern_file| with vblock from |image| stateful partition.""" |
| state_out = ExtractPartitionToTempFile(image, constants.PART_STATE) |
| vblock = tempfile.mktemp(prefix='vmlinuz_hd.vblock') |
| cros_build_lib.RunCommand(['e2cp', '%s:/vmlinuz_hd.vblock' % state_out, |
| vblock]) |
| |
| CopyFileSegment(vblock, 'r', os.path.getsize(vblock), kern_file, 'r+') |
| |
| osutils.SafeUnlink(state_out) |
| osutils.SafeUnlink(vblock) |
| |
| |
| def ExtractKernel(bin_file, kern_out): |
| """Extracts the kernel from the given |bin_file|, into |kern_out|.""" |
| kern_out = ExtractPartitionToTempFile(bin_file, constants.PART_KERN_B, |
| kern_out) |
| with open(kern_out, 'r') as kern: |
| if not any(kern.read(65536)): |
| logging.warn('%s: Kernel B is empty, patching kernel A.', bin_file) |
| ExtractPartitionToTempFile(bin_file, constants.PART_KERN_A, kern_out) |
| PatchKernel(bin_file, kern_out) |
| |
| return kern_out |
| |
| |
| def Ext2FileSystemSize(rootfs): |
| """Return the size in bytes of the ext2 filesystem passed in |rootfs|.""" |
| # dumpe2fs is normally installed in /sbin but doesn't require root. |
| dump = cros_build_lib.RunCommand(['/sbin/dumpe2fs', '-h', rootfs], |
| print_cmd=False, capture_output=True).output |
| fs_blocks = 0 |
| fs_blocksize = 0 |
| for line in dump.split('\n'): |
| if not line: |
| continue |
| label, data = line.split(':')[:2] |
| if label == 'Block count': |
| fs_blocks = int(data) |
| elif label == 'Block size': |
| fs_blocksize = int(data) |
| |
| return fs_blocks * fs_blocksize |
| |
| |
| def ExtractRoot(bin_file, root_out, root_pretruncate=None): |
| """Extract the rootfs partition from the gpt image |bin_file|. |
| |
| Stores it in |root_out|. If |root_out| is empty, a new temp file will be used. |
| If |root_pretruncate| is non-empty, saves the pretruncated rootfs partition |
| there. |
| """ |
| root_out = ExtractPartitionToTempFile(bin_file, constants.PART_ROOT_A, |
| root_out) |
| |
| if root_pretruncate: |
| logging.info('Saving pre-truncated root as %s.', root_pretruncate) |
| shutil.copyfile(root_out, root_pretruncate) |
| |
| # We only update the filesystem part of the partition, which is stored in the |
| # gpt script. |
| root_out_size = Ext2FileSystemSize(root_out) |
| if root_out_size: |
| with open(root_out, 'a') as root: |
| logging.info('Root size currently %d bytes.', os.path.getsize(root_out)) |
| root.truncate(root_out_size) |
| logging.info('Truncated root to %d bytes.', root_out_size) |
| else: |
| raise IOError('Error truncating the rootfs to filesystem size.') |
| |
| return root_out |
| |
| |
| def GenerateUpdatePayload(opts): |
| """Generates the output files for the given commandline |opts|.""" |
| # TODO(tbrindus): we can support calling outside of chroot easily with |
| # RunCommand, so we can remove this restriction. |
| if opts.src_image and not opts.outside_chroot: |
| # We need to be in the chroot for generating delta images. By specifying |
| # --outside_chroot you can choose not to assert this, which will allow us to |
| # run this script outside chroot. Running this script outside chroot |
| # requires copying a delta_generator binary and some related shared |
| # libraries. |
| cros_build_lib.AssertInsideChroot() |
| try: |
| src_kernel_path = src_root_path = dst_kernel_path = dst_root_path = '' |
| |
| if opts.extract: |
| if opts.src_image: |
| src_kernel_path = opts.src_kern_path or 'old_kern.dat' |
| src_root_path = opts.src_root_path or 'old_root.dat' |
| ExtractKernel(opts.src_image, src_kernel_path) |
| ExtractRoot(opts.src_image, src_root_path) |
| if opts.image: |
| dst_kernel_path = opts.kern_path or 'new_kern.dat' |
| dst_root_path = opts.root_path or 'new_root.dat' |
| ExtractKernel(opts.image, dst_kernel_path) |
| ExtractRoot(opts.image, dst_root_path, opts.root_pretruncate_path) |
| logging.info('Done extracting kernel/root') |
| return |
| |
| delta, payload_type = (True, 'delta') if opts.src_image else (False, 'full') |
| |
| logging.info('Generating %s update', payload_type) |
| |
| if delta: |
| if not opts.full_kernel: |
| src_kernel_path = ExtractKernel(opts.src_image, opts.src_kern_path) |
| else: |
| logging.info('Generating full kernel update') |
| |
| src_root_path = ExtractRoot(opts.src_image, opts.src_root_path) |
| |
| dst_kernel_path = ExtractKernel(opts.image, opts.kern_path) |
| dst_root_path = ExtractRoot(opts.image, opts.root_path, |
| opts.root_pretruncate_path) |
| |
| # TODO(tbrindus): delta_generator should be called with partition lists |
| # to support major version 2 more easily. |
| generator_args = [ |
| # Common payload args: |
| '--major_version=1', |
| '--out_file=' + opts.output, |
| '--private_key=' + (opts.private_key or ''), |
| '--out_metadata_size_file=' + (opts.out_metadata_size_file or ''), |
| # Target image args: |
| '--new_image=' + dst_root_path, |
| '--new_kernel=' + dst_kernel_path, |
| '--new_channel=' + opts.channel, |
| '--new_board=' + opts.board, |
| '--new_version=' + opts.version, |
| '--new_key=' + opts.key, |
| '--new_build_channel=' + opts.build_channel, |
| '--new_build_version=' + opts.build_version, |
| ] |
| |
| if delta: |
| generator_args += [ |
| # Source image args: |
| '--old_image=' + src_root_path, |
| '--old_kernel=' + src_kernel_path, |
| '--old_channel=' + opts.src_channel, |
| '--old_board=' + opts.src_board, |
| '--old_version=' + opts.src_version, |
| '--old_key=' + opts.src_key, |
| '--old_build_channel=' + opts.src_build_channel, |
| '--old_build_version=' + opts.src_build_version, |
| ] |
| |
| # The passed chunk_size is only used for delta payload. Use |
| # delta_generator's default if no value is provided. |
| if opts.chunk_size: |
| logging.info('Forcing chunk size to %d', opts.chunk_size) |
| generator_args.append('--chunk_size=%d' % opts.chunk_size) |
| |
| # Add partition size. Only *required* for minor_version=1. |
| # TODO(tbrindus): deprecate this when we deprecate minor version 1. |
| dst_root_part_size = cros_build_lib.GetImageDiskPartitionInfo( |
| opts.image)[constants.PART_ROOT_A].size |
| |
| if dst_root_part_size: |
| logging.info('Using rootfs partition size: %d', dst_root_part_size) |
| generator_args.append('--rootfs_partition_size=%d' % dst_root_part_size) |
| else: |
| logging.info('Using the default partition size') |
| |
| cros_build_lib.RunCommand([_DELTA_GENERATOR] + generator_args) |
| |
| if opts.out_payload_hash_file or opts.out_metadata_hash_file: |
| # The out_metadata_hash_file flag requires out_hash_file flag to be set |
| # in delta_generator, if caller doesn't provide it, we set it to |
| # /dev/null. |
| out_payload_hash_file = opts.out_payload_hash_file or '/dev/null' |
| |
| # The manifest - unfortunately - contains two fields called |
| # signature_offset and signature_size with data about how the manifest is |
| # signed. This means we have to pass the signature size used. The value |
| # 256 is the number of bytes the SHA-256 hash value of the manifest signed |
| # with a 2048-bit RSA key occupies. |
| generator_args = [ |
| '--in_file=' + opts.output, |
| '--signature_size=256', |
| '--out_hash_file=' + out_payload_hash_file, |
| '--out_metadata_hash_file=' + (opts.out_metadata_hash_file or ''), |
| ] |
| cros_build_lib.RunCommand([_DELTA_GENERATOR] + generator_args) |
| |
| logging.info('Done generating %s update', payload_type) |
| finally: |
| if not opts.src_kern_path: |
| osutils.SafeUnlink(src_kernel_path) |
| if not opts.src_root_path: |
| osutils.SafeUnlink(src_root_path) |
| if not opts.kern_path: |
| osutils.SafeUnlink(dst_kernel_path) |
| if not opts.root_path: |
| osutils.SafeUnlink(dst_root_path) |
| |
| |
| def ParseArguments(argv): |
| """Returns a namespace for the CLI arguments.""" |
| parser = commandline.ArgumentParser(description=__doc__) |
| parser.add_argument('--image', type='path', |
| help='The image that should be sent to clients.') |
| parser.add_argument('--src_image', type='path', |
| help='A source image. If specified, this makes a delta ' |
| 'update.') |
| parser.add_argument('--output', type='path', help='Output file.') |
| parser.add_argument('--outside_chroot', action='store_true', |
| help='Running outside of chroot.') |
| parser.add_argument('--private_key', type='path', |
| help='Path to private key in .pem format.') |
| parser.add_argument('--out_payload_hash_file', type='path', |
| help='Path to output payload hash file.') |
| parser.add_argument('--out_metadata_hash_file', type='path', |
| help='Path to output metadata hash file.') |
| parser.add_argument('--out_metadata_size_file', type='path', |
| help='Path to output metadata size file.') |
| parser.add_argument('--extract', action='store_true', |
| help='If set, extract old/new kernel/rootfs to ' |
| '[old|new]_[kern|root].dat. Useful for debugging.') |
| parser.add_argument('--full_kernel', action='store_true', |
| help='Generate a full kernel update even if generating a ' |
| 'delta update.') |
| parser.add_argument('--chunk_size', type=int, |
| help='Delta payload chunk size (-1 means whole files).') |
| |
| # TODO(tbrindus): Remove --build_version and --src_build_version flags. |
| src_group = parser.add_argument_group('Source options') |
| src_group.add_argument('--src_channel', type=str, default='', |
| help='Channel of the src image.') |
| src_group.add_argument('--src_board', type=str, default='', |
| help='Board of the src image.') |
| src_group.add_argument('--src_version', type=str, default='', |
| help='Version of the src image.') |
| src_group.add_argument('--src_key', type=str, default='', |
| help='Key of the src image.') |
| src_group.add_argument('--src_build_channel', type=str, default='', |
| help='Channel of the build of the src image.') |
| src_group.add_argument('--src_build_version', type=str, default='', |
| help='Channel of the build of the the src image.') |
| |
| dst_group = parser.add_argument_group('Target options') |
| dst_group.add_argument('--channel', type=str, default='', |
| help='Channel of the target image.') |
| dst_group.add_argument('--board', type=str, default='', |
| help='Board of the target image.') |
| dst_group.add_argument('--version', type=str, default='', |
| help='Version of the target image.') |
| dst_group.add_argument('--key', type=str, default='', |
| help='Key of the target image.') |
| dst_group.add_argument('--build_channel', type=str, default='', |
| help='Channel of the build of the target image.') |
| dst_group.add_argument('--build_version', type=str, default='', |
| help='Channel of the build of the the target image.') |
| |
| # Because we archive/call old versions of this script, we can't easily remove |
| # command line options, even if we ignore this one now. |
| parser.add_argument('--patch_kernel', action='store_true', |
| help='Ignored. Present for compatibility.') |
| |
| # Specifying any of the following will cause it to not be cleaned up on exit. |
| parser.add_argument('--kern_path', type='path', |
| help='File path for extracting the kernel partition.') |
| parser.add_argument('--root_path', type='path', |
| help='File path for extracting the rootfs partition.') |
| parser.add_argument('--root_pretruncate_path', type='path', |
| help='File path for extracting the rootfs partition, ' |
| 'pre-truncation.') |
| parser.add_argument('--src_kern_path', type='path', |
| help='File path for extracting the source kernel ' |
| 'partition.') |
| parser.add_argument('--src_root_path', type='path', |
| help='File path for extracting the source root ' |
| 'partition.') |
| |
| opts = parser.parse_args(argv) |
| opts.Freeze() |
| |
| if not opts.extract and not opts.output: |
| parser.error('You must specify an output filename with --output FILENAME') |
| |
| return opts |
| |
| |
| def main(argv): |
| opts = ParseArguments(argv) |
| |
| return GenerateUpdatePayload(opts) |
