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#!/usr/bin/env python
#
# Copyright (C) 2019 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.
"""deapexer is a tool that prints out content of an APEX.
To print content of an APEX to stdout:
deapexer list foo.apex
To extract content of an APEX to the given directory:
deapexer extract foo.apex dest
"""
from __future__ import print_function
import argparse
import apex_manifest
import enum
import os
import shutil
import sys
import subprocess
import tempfile
import zipfile
BLOCK_SIZE = 4096
class ApexImageEntry(object):
def __init__(self, name, base_dir, permissions, size, ino, extents,
is_directory, is_symlink, security_context):
self._name = name
self._base_dir = base_dir
self._permissions = permissions
self._size = size
self._is_directory = is_directory
self._is_symlink = is_symlink
self._ino = ino
self._extents = extents
self._security_context = security_context
@property
def name(self):
return self._name
@property
def root(self):
return self._base_dir == './' and self._name == '.'
@property
def full_path(self):
if self.root:
return self._base_dir # './'
path = os.path.join(self._base_dir, self._name)
if self.is_directory:
path += '/'
return path
@property
def is_directory(self):
return self._is_directory
@property
def is_symlink(self):
return self._is_symlink
@property
def is_regular_file(self):
return not self.is_directory and not self.is_symlink
@property
def permissions(self):
return self._permissions
@property
def size(self):
return self._size
@property
def ino(self):
return self._ino
@property
def extents(self):
return self._extents
@property
def security_context(self):
return self._security_context
def __str__(self):
ret = ''
if self._is_directory:
ret += 'd'
elif self._is_symlink:
ret += 'l'
else:
ret += '-'
def mask_as_string(m):
ret = 'r' if m & 4 == 4 else '-'
ret += 'w' if m & 2 == 2 else '-'
ret += 'x' if m & 1 == 1 else '-'
return ret
ret += mask_as_string(self._permissions >> 6)
ret += mask_as_string((self._permissions >> 3) & 7)
ret += mask_as_string(self._permissions & 7)
return ret + ' ' + self._size + ' ' + self._name
class ApexImageDirectory(object):
def __init__(self, path, entries, apex):
self._path = path
self._entries = sorted(entries, key=lambda e: e.name)
self._apex = apex
def list(self, is_recursive=False):
for e in self._entries:
yield e
if e.is_directory and e.name != '.' and e.name != '..':
for ce in self.enter_subdir(e).list(is_recursive):
yield ce
def enter_subdir(self, entry):
return self._apex._list(self._path + entry.name + '/')
def extract(self, dest):
path = self._path
self._apex._extract(self._path, dest)
class Apex(object):
def __init__(self, args):
self._debugfs = args.debugfs_path
self._fsckerofs = args.fsckerofs_path
self._blkid = args.blkid_path
self._apex = args.apex
self._tempdir = tempfile.mkdtemp()
# TODO(b/139125405): support flattened APEXes.
with zipfile.ZipFile(self._apex, 'r') as zip_ref:
self._payload = zip_ref.extract('apex_payload.img', path=self._tempdir)
self._cache = {}
def __del__(self):
shutil.rmtree(self._tempdir)
def __enter__(self):
return self._list('./')
def __exit__(self, type, value, traceback):
pass
def _list(self, path):
if path in self._cache:
return self._cache[path]
process = subprocess.Popen([self._debugfs, '-R', 'ls -l -p %s' % path, self._payload],
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
universal_newlines=True)
stdout, _ = process.communicate()
res = str(stdout)
entries = []
for line in res.split('\n'):
if not line:
continue
parts = line.split('/')
if len(parts) != 8:
continue
name = parts[5]
if not name:
continue
ino = parts[1]
bits = parts[2]
size = parts[6]
extents = []
is_symlink = bits[1]=='2'
is_directory=bits[1]=='4'
if not is_symlink and not is_directory:
process = subprocess.Popen([self._debugfs, '-R', 'dump_extents <%s>' % ino,
self._payload], stdout=subprocess.PIPE, stderr=subprocess.PIPE,
universal_newlines=True)
stdout, _ = process.communicate()
# Output of dump_extents for an inode fragmented in 3 blocks (length and addresses represent
# block-sized sections):
# Level Entries Logical Physical Length Flags
# 0/ 0 1/ 3 0 - 0 18 - 18 1
# 0/ 0 2/ 3 1 - 15 20 - 34 15
# 0/ 0 3/ 3 16 - 1863 37 - 1884 1848
res = str(stdout).splitlines()
res.pop(0) # the first line contains only columns names
left_length = int(size)
try: # dump_extents sometimes has an unexpected output
for line in res:
tokens = line.split()
offset = int(tokens[7]) * BLOCK_SIZE
length = min(int(tokens[-1]) * BLOCK_SIZE, left_length)
left_length -= length
extents.append((offset, length))
if (left_length != 0): # dump_extents sometimes fails to display "hole" blocks
raise ValueError
except:
extents = [] # [] means that we failed to retrieve the file location successfully
# get 'security.selinux' attribute
entry_path = os.path.join(path, name)
stdout = subprocess.check_output([
self._debugfs,
'-R',
f'ea_get -V {entry_path} security.selinux',
self._payload
], text=True, stderr=subprocess.DEVNULL)
security_context = stdout.rstrip('\n\x00')
entries.append(ApexImageEntry(name,
base_dir=path,
permissions=int(bits[3:], 8),
size=size,
is_directory=is_directory,
is_symlink=is_symlink,
ino=ino,
extents=extents,
security_context=security_context))
return ApexImageDirectory(path, entries, self)
def _extract(self, path, dest):
# get filesystem type
process = subprocess.Popen([self._blkid, '-o', 'value', '-s', 'TYPE', self._payload],
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
universal_newlines=True)
output, stderr = process.communicate()
if process.returncode != 0:
print(stderr, file=sys.stderr)
if output.rstrip() == 'erofs':
process = subprocess.Popen([self._fsckerofs, '--extract=%s' % (dest), '--overwrite', self._payload],
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
universal_newlines=True)
else:
process = subprocess.Popen([self._debugfs, '-R', 'rdump %s %s' % (path, dest), self._payload],
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
universal_newlines=True)
_, stderr = process.communicate()
if process.returncode != 0:
print(stderr, file=sys.stderr)
def RunList(args):
if GetType(args.apex) == ApexType.COMPRESSED:
with tempfile.TemporaryDirectory() as temp:
decompressed_apex = os.path.join(temp, 'temp.apex')
decompress(args.apex, decompressed_apex)
args.apex = decompressed_apex
RunList(args)
return
with Apex(args) as apex:
for e in apex.list(is_recursive=True):
# dot(., ..) directories
if not e.root and e.name in ('.', '..'):
continue
res = ''
if args.size:
res += e.size + ' '
res += e.full_path
if args.extents:
res += ' [' + '-'.join(str(x) for x in e.extents) + ']'
if args.contexts:
res += ' ' + e.security_context
print(res)
def RunExtract(args):
if GetType(args.apex) == ApexType.COMPRESSED:
with tempfile.TemporaryDirectory() as temp:
decompressed_apex = os.path.join(temp, "temp.apex")
decompress(args.apex, decompressed_apex)
args.apex = decompressed_apex
RunExtract(args)
return
with Apex(args) as apex:
if not os.path.exists(args.dest):
os.makedirs(args.dest, mode=0o755)
apex.extract(args.dest)
if os.path.isdir(os.path.join(args.dest, "lost+found")):
shutil.rmtree(os.path.join(args.dest, "lost+found"))
class ApexType(enum.Enum):
INVALID = 0
UNCOMPRESSED = 1
COMPRESSED = 2
def GetType(apex_path):
with zipfile.ZipFile(apex_path, 'r') as zip_file:
names = zip_file.namelist()
has_payload = 'apex_payload.img' in names
has_original_apex = 'original_apex' in names
if has_payload and has_original_apex:
return ApexType.INVALID
if has_payload:
return ApexType.UNCOMPRESSED
if has_original_apex:
return ApexType.COMPRESSED
return ApexType.INVALID
def RunInfo(args):
if args.print_type:
res = GetType(args.apex)
if res == ApexType.INVALID:
print(args.apex + ' is not a valid apex')
sys.exit(1)
print(res.name)
else:
manifest = apex_manifest.fromApex(args.apex)
print(apex_manifest.toJsonString(manifest))
def RunDecompress(args):
"""RunDecompress takes path to compressed APEX and decompresses it to
produce the original uncompressed APEX at give output path
See apex_compression_tool.py#RunCompress for details on compressed APEX
structure.
Args:
args.input: file path to compressed APEX
args.output: file path to where decompressed APEX will be placed
"""
compressed_apex_fp = args.input
decompressed_apex_fp = args.output
return decompress(compressed_apex_fp, decompressed_apex_fp)
def decompress(compressed_apex_fp, decompressed_apex_fp):
if os.path.exists(decompressed_apex_fp):
print("Output path '" + decompressed_apex_fp + "' already exists")
sys.exit(1)
with zipfile.ZipFile(compressed_apex_fp, 'r') as zip_obj:
if 'original_apex' not in zip_obj.namelist():
print(compressed_apex_fp + ' is not a compressed APEX. Missing '
"'original_apex' file inside it.")
sys.exit(1)
# Rename original_apex file to what user provided as output filename
original_apex_info = zip_obj.getinfo('original_apex')
original_apex_info.filename = os.path.basename(decompressed_apex_fp)
# Extract the original_apex as desired name
zip_obj.extract(original_apex_info,
path=os.path.dirname(decompressed_apex_fp))
def main(argv):
parser = argparse.ArgumentParser()
debugfs_default = None
fsckerofs_default = None
blkid_default = None
if 'ANDROID_HOST_OUT' in os.environ:
debugfs_default = '%s/bin/debugfs_static' % os.environ['ANDROID_HOST_OUT']
fsckerofs_default = '%s/bin/fsck.erofs' % os.environ['ANDROID_HOST_OUT']
blkid_default = '%s/bin/blkid_static' % os.environ['ANDROID_HOST_OUT']
parser.add_argument('--debugfs_path', help='The path to debugfs binary', default=debugfs_default)
parser.add_argument('--fsckerofs_path', help='The path to fsck.erofs binary', default=fsckerofs_default)
parser.add_argument('--blkid_path', help='The path to blkid binary', default=blkid_default)
subparsers = parser.add_subparsers(required=True, dest='cmd')
parser_list = subparsers.add_parser('list', help='prints content of an APEX to stdout')
parser_list.add_argument('apex', type=str, help='APEX file')
parser_list.add_argument('--size', help='also show the size of the files', action="store_true")
parser_list.add_argument('--extents', help='also show the location of the files', action="store_true")
parser_list.add_argument('-Z', '--contexts',
help='also show the security context of the files',
action='store_true')
parser_list.set_defaults(func=RunList)
parser_extract = subparsers.add_parser('extract', help='extracts content of an APEX to the given '
'directory')
parser_extract.add_argument('apex', type=str, help='APEX file')
parser_extract.add_argument('dest', type=str, help='Directory to extract content of APEX to')
parser_extract.set_defaults(func=RunExtract)
parser_info = subparsers.add_parser('info', help='prints APEX manifest')
parser_info.add_argument('apex', type=str, help='APEX file')
parser_info.add_argument('--print-type',
help='Prints type of the apex (COMPRESSED or UNCOMPRESSED)',
action='store_true')
parser_info.set_defaults(func=RunInfo)
# Handle sub-command "decompress"
parser_decompress = subparsers.add_parser('decompress',
help='decompresses a compressed '
'APEX')
parser_decompress.add_argument('--input', type=str, required=True,
help='path to compressed APEX file that '
'will be decompressed')
parser_decompress.add_argument('--output', type=str, required=True,
help='output directory path where '
'decompressed APEX will be extracted')
parser_decompress.set_defaults(func=RunDecompress)
args = parser.parse_args(argv)
debugfs_required_for_cmd = ['list', 'extract']
if args.cmd in debugfs_required_for_cmd and not args.debugfs_path:
print('ANDROID_HOST_OUT environment variable is not defined, --debugfs_path must be set',
file=sys.stderr)
sys.exit(1)
if args.cmd == 'extract':
if not args.blkid_path:
print('ANDROID_HOST_OUT environment variable is not defined, --blkid_path must be set',
file=sys.stderr)
sys.exit(1)
if not os.path.isfile(args.blkid_path):
print(f'Cannot find blkid specified at {args.blkid_path}',
file=sys.stderr)
sys.exit(1)
if not args.fsckerofs_path:
print('ANDROID_HOST_OUT environment variable is not defined, --fsckerofs_path must be set',
file=sys.stderr)
sys.exit(1)
if not os.path.isfile(args.fsckerofs_path):
print(f'Cannot find fsck.erofs specified at {args.fsckerofs_path}',
file=sys.stderr)
sys.exit(1)
args.func(args)
if __name__ == '__main__':
main(sys.argv[1:])
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