blob: 3fc65dc39afc6db0e1924a886936f5d2e2424578 [file] [log] [blame]
#!/usr/bin/python
#
# Copyright (c) 2013 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.
"""Command-line tool for checking and applying Chrome OS update payloads."""
import optparse
import os
import sys
# pylint: disable=F0401
lib_dir = os.path.join(os.path.dirname(__file__), 'lib')
if os.path.exists(lib_dir) and os.path.isdir(lib_dir):
sys.path.insert(1, lib_dir)
import update_payload
_TYPE_FULL = 'full'
_TYPE_DELTA = 'delta'
def ParseArguments(argv):
"""Parse and validate command-line arguments.
Args:
argv: command-line arguments to parse (excluding the program name)
Returns:
A tuple (opts, payload, extra_args), where `opts' are the options
returned by the parser, `payload' is the name of the payload file
(mandatory argument) and `extra_args' are any additional command-line
arguments.
"""
parser = optparse.OptionParser(
usage=('Usage: %prog [OPTION...] PAYLOAD [DST_KERN DST_ROOT '
'[SRC_KERN SRC_ROOT]]'),
description=('Applies a Chrome OS update PAYLOAD to SRC_KERN and '
'SRC_ROOT emitting DST_KERN and DST_ROOT, respectively. '
'SRC_KERN and SRC_ROOT are only needed for delta payloads. '
'When no partitions are provided, verifies the payload '
'integrity.'),
epilog=('Note: a payload may verify correctly but fail to apply, and '
'vice versa; this is by design and can be thought of as static '
'vs dynamic correctness. A payload that both verifies and '
'applies correctly should be safe for use by the Chrome OS '
'Update Engine. Use --check to verify a payload prior to '
'applying it.'))
default_key = os.path.join(lib_dir,
'update_payload/update-payload-key.pub.pem')
check_opts = optparse.OptionGroup(parser, 'Payload integrity checking')
check_opts.add_option('-c', '--check', action='store_true', default=False,
help=('force payload integrity check (e.g. before '
'applying)'))
check_opts.add_option('-r', '--report', metavar='FILE',
help="dump payload report (`-' for stdout)")
check_opts.add_option('-t', '--type', metavar='TYPE', dest='assert_type',
help=("assert that payload is either `%s' or `%s'" %
(_TYPE_FULL, _TYPE_DELTA)))
check_opts.add_option('-z', '--block-size', metavar='NUM', default=0,
type='int',
help='assert a non-default (4096) payload block size')
check_opts.add_option('-u', '--allow-unhashed', action='store_true',
default=False, help='allow unhashed operations')
check_opts.add_option('-d', '--disabled_tests', metavar='TESTLIST',
default=(),
help=('comma-separated list of tests to disable; '
'available values: ' +
', '.join(update_payload.CHECKS_TO_DISABLE)))
check_opts.add_option('-k', '--key', metavar='FILE',
help='Override standard key used for signature '
'validation',
default=default_key)
check_opts.add_option('-m', '--meta-sig', metavar='FILE',
help='verify metadata against its signature')
parser.add_option_group(check_opts)
trace_opts = optparse.OptionGroup(parser, 'Block tracing')
trace_opts.add_option('-b', '--root-block', metavar='BLOCK', type='int',
help='trace the origin for a rootfs block')
trace_opts.add_option('-B', '--kern-block', metavar='BLOCK', type='int',
help='trace the origin for a kernel block')
trace_opts.add_option('-s', '--skip', metavar='NUM', default='0', type='int',
help='skip first NUM occurrences of traced block')
parser.add_option_group(trace_opts)
# Parse command-line arguments.
opts, args = parser.parse_args(argv)
# Validate a value given to --type, if any.
if opts.assert_type not in (None, _TYPE_FULL, _TYPE_DELTA):
parser.error('invalid argument to --type: %s' % opts.assert_type)
# Convert and validate --disabled_tests value list, if provided.
if opts.disabled_tests:
opts.disabled_tests = opts.disabled_tests.split(',')
for test in opts.disabled_tests:
if test not in update_payload.CHECKS_TO_DISABLE:
parser.error('invalid argument to --disabled_tests: %s' % test)
# Ensure consistent use of block tracing options.
do_block_trace = opts.root_block or opts.kern_block
if opts.skip and not do_block_trace:
parser.error('--skip must be used with either --root-block or --kern-block')
# There are several options that imply --check.
opts.check = (opts.check or opts.report or opts.assert_type or
opts.block_size or opts.allow_unhashed or opts.key or
opts.meta_sig)
# Check number of arguments, enforce payload type accordingly.
if len(args) == 3:
if opts.assert_type == _TYPE_DELTA:
parser.error('%s payload requires source partition arguments' %
_TYPE_DELTA)
opts.assert_type = _TYPE_FULL
elif len(args) == 5:
if opts.assert_type == _TYPE_FULL:
parser.error('%s payload does not accept source partition arguments' %
_TYPE_FULL)
opts.assert_type = _TYPE_DELTA
elif len(args) == 1:
# Not applying payload; if block tracing not requested either, do an
# integrity check.
if not do_block_trace:
opts.check = True
else:
parser.error('unexpected number of arguments')
# By default, look for a metadata-signature file with a name based on the name
# of the payload we are checking.
if not opts.meta_sig:
print "Looking for default signature."
default_meta_sig = args[0] + '.metadata-signature'
if os.path.isfile(default_meta_sig):
opts.meta_sig = default_meta_sig
print "Using default signature %s." % opts.meta_sig
return opts, args[0], args[1:]
def main(argv):
# Parse and validate arguments.
options, payload_file_name, extra_args = ParseArguments(argv[1:])
with open(payload_file_name) as payload_file:
payload = update_payload.Payload(payload_file)
try:
# Initialize payload.
payload.Init()
# Perform payload integrity checks.
if options.check:
report_file = None
do_close_report_file = False
try:
if options.report:
if options.report == '-':
report_file = sys.stdout
else:
report_file = open(options.report, 'w')
do_close_report_file = True
payload.Check(
pubkey_file_name=options.key,
metadata_sig_file=open(options.meta_sig)
if options.meta_sig else None,
report_out_file=report_file,
assert_type=options.assert_type,
block_size=int(options.block_size),
allow_unhashed=options.allow_unhashed,
disabled_tests=options.disabled_tests)
finally:
if do_close_report_file:
report_file.close()
# Trace blocks.
if options.root_block is not None:
payload.TraceBlock(options.root_block, options.skip, sys.stdout, False)
if options.kern_block is not None:
payload.TraceBlock(options.kern_block, options.skip, sys.stdout, True)
# Apply payload.
if extra_args:
if options.assert_type == _TYPE_FULL:
payload.Apply(extra_args[0], extra_args[1])
elif options.assert_type == _TYPE_DELTA:
payload.Apply(extra_args[0], extra_args[1],
src_kernel_part=extra_args[2],
src_rootfs_part=extra_args[3])
else:
assert False, 'cannot get here'
except update_payload.PayloadError, e:
sys.stderr.write('Error: %s\n' % e)
return 1
return 0
if __name__ == '__main__':
sys.exit(main(sys.argv))