Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 1 | # Copyright 2021 The Chromium OS Authors. All rights reserved. |
| 2 | # Use of this source code is governed by a BSD-style license that can be |
| 3 | # found in the LICENSE file. |
| 4 | |
| 5 | """Library containing functions to install an image on a Chromium OS device.""" |
| 6 | |
Amin Hassani | d4b3ff8 | 2021-02-20 23:05:14 -0800 | [diff] [blame] | 7 | import abc |
Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 8 | import enum |
| 9 | import os |
| 10 | import re |
| 11 | import sys |
Amin Hassani | d4b3ff8 | 2021-02-20 23:05:14 -0800 | [diff] [blame] | 12 | import tempfile |
| 13 | import threading |
Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 14 | from typing import Tuple, Dict |
| 15 | |
Amin Hassani | d4b3ff8 | 2021-02-20 23:05:14 -0800 | [diff] [blame] | 16 | from chromite.lib import constants |
Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 17 | from chromite.lib import cros_build_lib |
| 18 | from chromite.lib import cros_logging as logging |
| 19 | from chromite.lib import gs |
Amin Hassani | d4b3ff8 | 2021-02-20 23:05:14 -0800 | [diff] [blame] | 20 | from chromite.lib import image_lib |
| 21 | from chromite.lib import osutils |
Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 22 | from chromite.lib import parallel |
| 23 | from chromite.lib import remote_access |
| 24 | from chromite.lib import retry_util |
Amin Hassani | 7440308 | 2021-02-22 11:40:09 -0800 | [diff] [blame^] | 25 | from chromite.lib import stateful_updater |
Amin Hassani | 75c5f94 | 2021-02-20 23:56:53 -0800 | [diff] [blame] | 26 | from chromite.lib.paygen import partition_lib |
Amin Hassani | 7440308 | 2021-02-22 11:40:09 -0800 | [diff] [blame^] | 27 | from chromite.lib.paygen import paygen_stateful_payload_lib |
Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 28 | from chromite.lib.xbuddy import devserver_constants |
| 29 | from chromite.lib.xbuddy import xbuddy |
| 30 | |
| 31 | |
| 32 | assert sys.version_info >= (3, 6), 'This module requires Python 3.6+' |
| 33 | |
| 34 | |
| 35 | class Error(Exception): |
| 36 | """Thrown when there is a general Chromium OS-specific flash error.""" |
| 37 | |
| 38 | |
| 39 | class ImageType(enum.Enum): |
| 40 | """Type of the image that is used for flashing the device.""" |
| 41 | |
| 42 | # The full image on disk (e.g. chromiumos_test_image.bin). |
| 43 | FULL = 0 |
| 44 | # The remote directory path |
| 45 | # (e.g gs://chromeos-image-archive/eve-release/R90-x.x.x) |
| 46 | REMOTE_DIRECTORY = 1 |
| 47 | |
| 48 | |
| 49 | class Partition(enum.Enum): |
| 50 | """An enum for partition types like kernel and rootfs.""" |
| 51 | KERNEL = 0 |
| 52 | ROOTFS = 1 |
| 53 | |
| 54 | |
| 55 | class DeviceImager(object): |
| 56 | """A class to flash a Chromium OS device. |
| 57 | |
| 58 | This utility uses parallelism as much as possible to achieve its goal as fast |
| 59 | as possible. For example, it uses parallel compressors, parallel transfers, |
| 60 | and simultaneous pipes. |
| 61 | """ |
| 62 | |
| 63 | # The parameters of the kernel and rootfs's two main partitions. |
| 64 | A = {Partition.KERNEL: 2, Partition.ROOTFS: 3} |
| 65 | B = {Partition.KERNEL: 4, Partition.ROOTFS: 5} |
| 66 | |
| 67 | def __init__(self, device, image: str, |
| 68 | no_rootfs_update: bool = False, |
| 69 | no_stateful_update: bool = False, |
| 70 | no_reboot: bool = False, |
| 71 | disable_verification: bool = False, |
| 72 | clobber_stateful: bool = False, |
| 73 | clear_tpm_owner: bool = False): |
| 74 | """Initialize DeviceImager for flashing a Chromium OS device. |
| 75 | |
| 76 | Args: |
| 77 | device: The ChromiumOSDevice to be updated. |
| 78 | image: The target image path (can be xBuddy path). |
| 79 | no_rootfs_update: Whether to do rootfs partition update. |
| 80 | no_stateful_update: Whether to do stateful partition update. |
| 81 | no_reboot: Whether to reboot device after update. The default is True. |
| 82 | disable_verification: Whether to disabling rootfs verification on the |
| 83 | device. |
| 84 | clobber_stateful: Whether to do a clean stateful partition. |
| 85 | clear_tpm_owner: If true, it will clear the TPM owner on reboot. |
| 86 | """ |
| 87 | |
| 88 | self._device = device |
| 89 | self._image = image |
| 90 | self._no_rootfs_update = no_rootfs_update |
| 91 | self._no_stateful_update = no_stateful_update |
| 92 | self._no_reboot = no_reboot |
| 93 | self._disable_verification = disable_verification |
| 94 | self._clobber_stateful = clobber_stateful |
| 95 | self._clear_tpm_owner = clear_tpm_owner |
| 96 | |
| 97 | self._compression = cros_build_lib.COMP_XZ |
| 98 | self._inactive_state = None |
| 99 | |
| 100 | def Run(self): |
| 101 | """Update the device with image of specific version.""" |
| 102 | |
| 103 | try: |
| 104 | self._Run() |
| 105 | except Exception as e: |
| 106 | raise Error(f'DeviceImager Failed with error: {e}') |
| 107 | |
| 108 | logging.info('DeviceImager completed.') |
| 109 | |
| 110 | def _Run(self): |
| 111 | """Runs the various operations to install the image on device.""" |
| 112 | image, image_type = self._GetImage() |
| 113 | logging.info('Using image %s of type %s', image, image_type ) |
| 114 | |
| 115 | if image_type == ImageType.REMOTE_DIRECTORY: |
| 116 | self._compression = cros_build_lib.COMP_GZIP |
| 117 | |
| 118 | self._InstallPartitions(image, image_type) |
| 119 | |
| 120 | if self._clear_tpm_owner: |
| 121 | self._device.ClearTpmOwner() |
| 122 | |
| 123 | if not self._no_reboot: |
| 124 | self._Reboot() |
| 125 | self._VerifyBootExpectations() |
| 126 | |
| 127 | if self._disable_verification: |
| 128 | self._device.DisableRootfsVerification() |
| 129 | |
| 130 | def _GetImage(self) -> Tuple[str, ImageType]: |
| 131 | """Returns the path to the final image(s) that need to be installed. |
| 132 | |
| 133 | If the paths is local, the image should be the Chromium OS GPT image |
| 134 | (e.g. chromiumos_test_image.bin). If the path is remote, it should be the |
| 135 | remote directory where we can find the quick-provision and stateful update |
| 136 | files (e.g. gs://chromeos-image-archive/eve-release/R90-x.x.x). |
| 137 | |
| 138 | NOTE: At this point there is no caching involved. Hence we always download |
| 139 | the partition payloads or extract them from the Chromium OS image. |
| 140 | |
| 141 | Returns: |
| 142 | A tuple of image path and image type. |
| 143 | """ |
| 144 | if os.path.isfile(self._image): |
| 145 | return self._image, ImageType.FULL |
| 146 | |
| 147 | # TODO(b/172212406): We could potentially also allow this by searching |
| 148 | # through the directory to see whether we have quick-provision and stateful |
| 149 | # payloads. This only makes sense when a user has their workstation at home |
| 150 | # and doesn't want to incur the bandwidth cost of downloading the same |
| 151 | # image multiple times. For that, they can simply download the GPT image |
| 152 | # image first and flash that instead. |
| 153 | if os.path.isdir(self._image): |
| 154 | raise ValueError( |
| 155 | f'{self._image}: input must be a disk image, not a directory.') |
| 156 | |
| 157 | if gs.PathIsGs(self._image): |
| 158 | # TODO(b/172212406): Check whether it is a directory. If it wasn't a |
| 159 | # directory download the image into some temp location and use it instead. |
| 160 | return self._image, ImageType.REMOTE_DIRECTORY |
| 161 | |
| 162 | # Assuming it is an xBuddy path. |
| 163 | xb = xbuddy.XBuddy(log_screen=False) |
| 164 | build_id, local_file = xb.Translate([self._image]) |
| 165 | if build_id is None: |
| 166 | raise Error(f'{self._image}: unable to find matching xBuddy path.') |
| 167 | logging.info('XBuddy path translated to build ID %s', build_id) |
| 168 | |
| 169 | if local_file: |
| 170 | return local_file, ImageType.FULL |
| 171 | |
| 172 | return (f'{devserver_constants.GS_IMAGE_DIR}/{build_id}', |
| 173 | ImageType.REMOTE_DIRECTORY) |
| 174 | |
| 175 | def _SplitDevPath(self, path: str) -> Tuple[str, int]: |
| 176 | """Splits the given /dev/x path into prefix and the dev number. |
| 177 | |
| 178 | Args: |
| 179 | path: The path to a block dev device. |
| 180 | |
| 181 | Returns: |
| 182 | A tuple of representing the prefix and the index of the dev path. |
| 183 | e.g.: '/dev/mmcblk0p1' -> ['/dev/mmcblk0p', 1] |
| 184 | """ |
| 185 | match = re.search(r'(.*)([0-9]+)$', path) |
| 186 | if match is None: |
| 187 | raise Error(f'{path}: Could not parse root dev path.') |
| 188 | |
| 189 | return match.group(1), int(match.group(2)) |
| 190 | |
| 191 | def _GetKernelState(self, root_num: int) -> Tuple[Dict, Dict]: |
| 192 | """Returns the kernel state. |
| 193 | |
| 194 | Returns: |
| 195 | A tuple of two dictionaries: The current active kernel state and the |
| 196 | inactive kernel state. (Look at A and B constants in this class.) |
| 197 | """ |
| 198 | if root_num == self.A[Partition.ROOTFS]: |
| 199 | return self.A, self.B |
| 200 | elif root_num == self.B[Partition.ROOTFS]: |
| 201 | return self.B, self.A |
| 202 | else: |
| 203 | raise Error(f'Invalid root partition number {root_num}') |
| 204 | |
| 205 | def _InstallPartitions(self, image: str, image_type): |
| 206 | """The main method that installs the partitions of a Chrome OS device. |
| 207 | |
| 208 | It uses parallelism to install the partitions as fast as possible. |
| 209 | |
| 210 | Args: |
| 211 | image: The image path (local file or remote directory). |
| 212 | image_type: The type of the image (ImageType). |
| 213 | """ |
Amin Hassani | d684e98 | 2021-02-26 11:10:58 -0800 | [diff] [blame] | 214 | prefix, root_num = self._SplitDevPath(self._device.root_dev) |
| 215 | active_state, self._inactive_state = self._GetKernelState(root_num) |
| 216 | |
Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 217 | updaters = [] |
Amin Hassani | d684e98 | 2021-02-26 11:10:58 -0800 | [diff] [blame] | 218 | if not self._no_rootfs_update: |
Amin Hassani | 75c5f94 | 2021-02-20 23:56:53 -0800 | [diff] [blame] | 219 | current_root = prefix + str(active_state[Partition.ROOTFS]) |
| 220 | target_root = prefix + str(self._inactive_state[Partition.ROOTFS]) |
| 221 | updaters.append(RootfsUpdater(current_root, self._device, image, |
| 222 | image_type, target_root, self._compression)) |
| 223 | |
Amin Hassani | d684e98 | 2021-02-26 11:10:58 -0800 | [diff] [blame] | 224 | target_kernel = prefix + str(self._inactive_state[Partition.KERNEL]) |
| 225 | updaters.append(KernelUpdater(self._device, image, image_type, |
| 226 | target_kernel, self._compression)) |
Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 227 | |
Amin Hassani | 7440308 | 2021-02-22 11:40:09 -0800 | [diff] [blame^] | 228 | if not self._no_stateful_update: |
| 229 | updaters.append(StatefulUpdater(self._clobber_stateful, self._device, |
| 230 | image, image_type, None, None)) |
| 231 | |
Amin Hassani | 92f6c4a | 2021-02-20 17:36:09 -0800 | [diff] [blame] | 232 | # Retry the partitions updates that failed, in case a transient error (like |
| 233 | # SSH drop, etc) caused the error. |
| 234 | num_retries = 1 |
| 235 | try: |
| 236 | retry_util.RetryException(Error, num_retries, |
| 237 | parallel.RunParallelSteps, |
| 238 | (x.Run for x in updaters if not x.IsFinished()), |
| 239 | halt_on_error=True) |
| 240 | except Exception: |
| 241 | # If one of the partitions failed to be installed, revert all partitions. |
| 242 | parallel.RunParallelSteps(x.Revert for x in updaters) |
| 243 | raise |
| 244 | |
| 245 | def _Reboot(self): |
| 246 | """Reboots the device.""" |
| 247 | try: |
| 248 | self._device.Reboot(timeout_sec=60) |
| 249 | except remote_access.RebootError: |
| 250 | raise Error('Could not recover from reboot. Once example reason' |
| 251 | ' could be the image provided was a non-test image' |
| 252 | ' or the system failed to boot after the update.') |
| 253 | except Exception as e: |
| 254 | raise Error(f'Failed to reboot to the device with error: {e}') |
| 255 | |
| 256 | def _VerifyBootExpectations(self): |
| 257 | """Verify that we fully booted into the expected kernel state.""" |
| 258 | # Discover the newly active kernel. |
| 259 | _, root_num = self._SplitDevPath(self._device.root_dev) |
| 260 | active_state, _ = self._GetKernelState(root_num) |
| 261 | |
| 262 | # If this happens, we should rollback. |
| 263 | if active_state != self._inactive_state: |
| 264 | raise Error('The expected kernel state after update is invalid.') |
| 265 | |
| 266 | logging.info('Verified boot expectations.') |
Amin Hassani | d4b3ff8 | 2021-02-20 23:05:14 -0800 | [diff] [blame] | 267 | |
| 268 | |
| 269 | class ReaderBase(threading.Thread): |
| 270 | """The base class for reading different inputs and writing into output. |
| 271 | |
| 272 | This class extends threading.Thread, so it will be run on its own thread. Also |
| 273 | it can be used as a context manager. Internally, it opens necessary files for |
| 274 | writing to and reading from. This class cannot be instantiated, it needs to be |
| 275 | sub-classed first to provide necessary function implementations. |
| 276 | """ |
| 277 | |
| 278 | def __init__(self, use_named_pipes: bool = False): |
| 279 | """Initializes the class. |
| 280 | |
| 281 | Args: |
| 282 | use_named_pipes: Whether to use a named pipe or anonymous file |
| 283 | descriptors. |
| 284 | """ |
| 285 | super().__init__() |
| 286 | self._use_named_pipes = use_named_pipes |
| 287 | self._pipe_target = None |
| 288 | self._pipe_source = None |
| 289 | |
| 290 | def __del__(self): |
| 291 | """Destructor. |
| 292 | |
| 293 | Make sure to clean up any named pipes we might have created. |
| 294 | """ |
| 295 | if self._use_named_pipes: |
| 296 | osutils.SafeUnlink(self._pipe_target) |
| 297 | |
| 298 | def __enter__(self): |
| 299 | """Enters the context manager""" |
| 300 | if self._use_named_pipes: |
| 301 | # There is no need for the temp file, we only need its path. So the named |
| 302 | # pipe is created after this temp file is deleted. |
| 303 | with tempfile.NamedTemporaryFile(prefix='chromite-device-imager') as fp: |
| 304 | self._pipe_target = self._pipe_source = fp.name |
| 305 | os.mkfifo(self._pipe_target) |
| 306 | else: |
| 307 | self._pipe_target, self._pipe_source = os.pipe() |
| 308 | |
| 309 | self.start() |
| 310 | return self |
| 311 | |
| 312 | def __exit__(self, *args, **kwargs): |
| 313 | """Exits the context manager.""" |
| 314 | self.join() |
| 315 | |
| 316 | def _Source(self): |
| 317 | """Returns the source pipe to write data into. |
| 318 | |
| 319 | Sub-classes can use this function to determine where to write their data |
| 320 | into. |
| 321 | """ |
| 322 | return self._pipe_source |
| 323 | |
| 324 | def _CloseSource(self): |
| 325 | """Closes the source pipe. |
| 326 | |
| 327 | Sub-classes should use this function to close the pipe after they are done |
| 328 | writing into it. Failure to do so may result reader of the data to hang |
| 329 | indefinitely. |
| 330 | """ |
| 331 | if not self._use_named_pipes: |
| 332 | os.close(self._pipe_source) |
| 333 | |
| 334 | def Target(self): |
| 335 | """Returns the target pipe to read data from. |
| 336 | |
| 337 | Users of this class can use this path to read data from. |
| 338 | """ |
| 339 | return self._pipe_target |
| 340 | |
| 341 | def CloseTarget(self): |
| 342 | """Closes the target pipe. |
| 343 | |
| 344 | Users of this class should use this function to close the pipe after they |
| 345 | are done reading from it. |
| 346 | """ |
| 347 | if self._use_named_pipes: |
| 348 | os.remove(self._pipe_target) |
| 349 | else: |
| 350 | os.close(self._pipe_target) |
| 351 | |
| 352 | |
| 353 | class PartialFileReader(ReaderBase): |
| 354 | """A class to read specific offset and length from a file and compress it. |
| 355 | |
| 356 | This class can be used to read from specific location and length in a file |
| 357 | (e.g. A partition in a GPT image). Then it compresses the input and writes it |
| 358 | out (to a pipe). Look at the base class for more information. |
| 359 | """ |
| 360 | |
| 361 | # The offset of different partitions in a Chromium OS image does not always |
| 362 | # align to larger values like 4096. It seems that 512 is the maximum value to |
| 363 | # be divisible by partition offsets. This size should not be increased just |
| 364 | # for 'performance reasons'. Since we are doing everything in parallel, in |
| 365 | # practice there is not much difference between this and larger block sizes as |
| 366 | # parallelism hides the possible extra latency provided by smaller block |
| 367 | # sizes. |
| 368 | _BLOCK_SIZE = 512 |
| 369 | |
| 370 | def __init__(self, image: str, offset: int, length: int, compression): |
| 371 | """Initializes the class. |
| 372 | |
| 373 | Args: |
| 374 | image: The path to an image (local or remote directory). |
| 375 | offset: The offset (in bytes) to read from the image. |
| 376 | length: The length (in bytes) to read from the image. |
| 377 | compression: The compression type (see cros_build_lib.COMP_XXX). |
| 378 | """ |
| 379 | super().__init__() |
| 380 | |
| 381 | self._image = image |
| 382 | self._offset = offset |
| 383 | self._length = length |
| 384 | self._compression = compression |
| 385 | |
| 386 | def run(self): |
| 387 | """Runs the reading and compression.""" |
| 388 | cmd = [ |
| 389 | 'dd', |
| 390 | 'status=none', |
| 391 | f'if={self._image}', |
| 392 | f'ibs={self._BLOCK_SIZE}', |
| 393 | f'skip={int(self._offset/self._BLOCK_SIZE)}', |
| 394 | f'count={int(self._length/self._BLOCK_SIZE)}', |
| 395 | '|', |
| 396 | cros_build_lib.FindCompressor(self._compression), |
| 397 | ] |
| 398 | |
| 399 | try: |
| 400 | cros_build_lib.run(' '.join(cmd), stdout=self._Source(), shell=True) |
| 401 | finally: |
| 402 | self._CloseSource() |
| 403 | |
| 404 | |
Amin Hassani | 0fe49ae | 2021-02-21 23:41:58 -0800 | [diff] [blame] | 405 | class GsFileCopier(ReaderBase): |
| 406 | """A class for downloading gzip compressed file from GS bucket into a pipe.""" |
| 407 | |
| 408 | def __init__(self, image: str): |
| 409 | """Initializes the class. |
| 410 | |
| 411 | Args: |
| 412 | image: The path to an image (local or remote directory). |
| 413 | """ |
| 414 | super().__init__(use_named_pipes=True) |
| 415 | self._image = image |
| 416 | |
| 417 | def run(self): |
| 418 | """Runs the download and write into the output pipe.""" |
| 419 | try: |
| 420 | gs.GSContext().Copy(self._image, self._Source()) |
| 421 | finally: |
| 422 | self._CloseSource() |
| 423 | |
| 424 | |
Amin Hassani | d4b3ff8 | 2021-02-20 23:05:14 -0800 | [diff] [blame] | 425 | class PartitionUpdaterBase(object): |
| 426 | """A base abstract class to use for installing an image into a partition. |
| 427 | |
| 428 | Sub-classes should implement the abstract methods to provide the core |
| 429 | functionality. |
| 430 | """ |
| 431 | def __init__(self, device, image: str, image_type, target: str, compression): |
| 432 | """Initializes this base class with values that most sub-classes will need. |
| 433 | |
| 434 | Args: |
| 435 | device: The ChromiumOSDevice to be updated. |
| 436 | image: The target image path for the partition update. |
| 437 | image_type: The type of the image (ImageType). |
| 438 | target: The target path (e.g. block dev) to install the update. |
| 439 | compression: The compression used for compressing the update payload. |
| 440 | """ |
| 441 | self._device = device |
| 442 | self._image = image |
| 443 | self._image_type = image_type |
| 444 | self._target = target |
| 445 | self._compression = compression |
| 446 | self._finished = False |
| 447 | |
| 448 | def Run(self): |
| 449 | """The main function that does the partition update job.""" |
| 450 | with cros_build_lib.TimedSection() as timer: |
| 451 | try: |
| 452 | self._Run() |
| 453 | finally: |
| 454 | self._finished = True |
| 455 | |
| 456 | logging.debug('Completed %s in %s', self.__class__.__name__, timer.delta) |
| 457 | |
| 458 | @abc.abstractmethod |
| 459 | def _Run(self): |
| 460 | """The method that need to be implemented by sub-classes.""" |
| 461 | raise NotImplementedError('Sub-classes need to implement this.') |
| 462 | |
| 463 | def IsFinished(self): |
| 464 | """Returns whether the partition update has been successful.""" |
| 465 | return self._finished |
| 466 | |
| 467 | @abc.abstractmethod |
| 468 | def Revert(self): |
| 469 | """Reverts the partition update. |
| 470 | |
| 471 | Sub-classes need to implement this function to provide revert capability. |
| 472 | """ |
| 473 | raise NotImplementedError('Sub-classes need to implement this.') |
| 474 | |
| 475 | |
| 476 | class RawPartitionUpdater(PartitionUpdaterBase): |
| 477 | """A class to update a raw partition on a Chromium OS device.""" |
| 478 | |
| 479 | def _Run(self): |
| 480 | """The function that does the job of kernel partition update.""" |
| 481 | if self._image_type == ImageType.FULL: |
| 482 | self._CopyPartitionFromImage(self._GetPartitionName()) |
| 483 | elif self._image_type == ImageType.REMOTE_DIRECTORY: |
Amin Hassani | 0fe49ae | 2021-02-21 23:41:58 -0800 | [diff] [blame] | 484 | self._RedirectPartition(self._GetRemotePartitionName()) |
Amin Hassani | d4b3ff8 | 2021-02-20 23:05:14 -0800 | [diff] [blame] | 485 | else: |
| 486 | raise ValueError(f'Invalid image type {self._image_type}') |
| 487 | |
| 488 | def _GetPartitionName(self): |
| 489 | """Returns the name of the partition in a Chromium OS GPT layout. |
| 490 | |
| 491 | Subclasses should override this function to return correct name. |
| 492 | """ |
| 493 | raise NotImplementedError('Subclasses need to implement this.') |
| 494 | |
| 495 | def _CopyPartitionFromImage(self, part_name: str): |
| 496 | """Updates the device's partition from a local Chromium OS image. |
| 497 | |
| 498 | Args: |
| 499 | part_name: The name of the partition in the source image that needs to be |
| 500 | extracted. |
| 501 | """ |
| 502 | cmd = self._GetWriteToTargetCommand() |
| 503 | |
| 504 | offset, length = self._GetPartLocation(part_name) |
| 505 | offset, length = self._OptimizePartLocation(offset, length) |
| 506 | with PartialFileReader(self._image, offset, length, |
| 507 | self._compression) as generator: |
| 508 | try: |
| 509 | self._device.run(cmd, input=generator.Target(), shell=True) |
| 510 | finally: |
| 511 | generator.CloseTarget() |
| 512 | |
| 513 | def _GetWriteToTargetCommand(self): |
| 514 | """Returns a write to target command to run on a Chromium OS device. |
| 515 | |
| 516 | Returns: |
| 517 | A string command to run on a device to read data from stdin, uncompress it |
| 518 | and write it to the target partition. |
| 519 | """ |
| 520 | cmd = self._device.GetDecompressor(self._compression) |
| 521 | # Using oflag=direct to tell the OS not to cache the writes (faster). |
| 522 | cmd += ['|', 'dd', 'bs=1M', 'oflag=direct', f'of={self._target}'] |
| 523 | return ' '.join(cmd) |
| 524 | |
| 525 | def _GetPartLocation(self, part_name: str): |
| 526 | """Extracts the location and size of the kernel partition from the image. |
| 527 | |
| 528 | Args: |
| 529 | part_name: The name of the partition in the source image that needs to be |
| 530 | extracted. |
| 531 | |
| 532 | Returns: |
| 533 | A tuple of offset and length (in bytes) from the image. |
| 534 | """ |
| 535 | try: |
| 536 | parts = image_lib.GetImageDiskPartitionInfo(self._image) |
| 537 | part_info = [p for p in parts if p.name == part_name][0] |
| 538 | except IndexError: |
| 539 | raise Error(f'No partition named {part_name} found.') |
| 540 | |
| 541 | return int(part_info.start), int(part_info.size) |
| 542 | |
Amin Hassani | 0fe49ae | 2021-02-21 23:41:58 -0800 | [diff] [blame] | 543 | def _GetRemotePartitionName(self): |
| 544 | """Returns the name of the quick-provision partition file. |
| 545 | |
| 546 | Subclasses should override this function to return correct name. |
| 547 | """ |
| 548 | raise NotImplementedError('Subclasses need to implement this.') |
| 549 | |
Amin Hassani | d4b3ff8 | 2021-02-20 23:05:14 -0800 | [diff] [blame] | 550 | def _OptimizePartLocation(self, offset: int, length: int): |
| 551 | """Optimizes the offset and length of the partition. |
| 552 | |
| 553 | Subclasses can override this to provide better offset/length than what is |
| 554 | defined in the PGT partition layout. |
| 555 | |
| 556 | Args: |
| 557 | offset: The offset (in bytes) of the partition in the image. |
| 558 | length: The length (in bytes) of the partition. |
| 559 | |
| 560 | Returns: |
| 561 | A tuple of offset and length (in bytes) from the image. |
| 562 | """ |
| 563 | return offset, length |
Amin Hassani | d684e98 | 2021-02-26 11:10:58 -0800 | [diff] [blame] | 564 | |
Amin Hassani | 0fe49ae | 2021-02-21 23:41:58 -0800 | [diff] [blame] | 565 | def _RedirectPartition(self, file_name: str): |
| 566 | """Downloads the partition from a remote path and writes it into target. |
| 567 | |
| 568 | Args: |
| 569 | file_name: The file name in the remote directory self._image. |
| 570 | """ |
| 571 | cmd = self._GetWriteToTargetCommand() |
| 572 | |
| 573 | image_path = os.path.join(self._image, file_name) |
| 574 | with GsFileCopier(image_path) as generator: |
| 575 | try: |
| 576 | with open(generator.Target(), 'rb') as fp: |
| 577 | self._device.run(cmd, input=fp, shell=True) |
| 578 | finally: |
| 579 | generator.CloseTarget() |
| 580 | |
Amin Hassani | d684e98 | 2021-02-26 11:10:58 -0800 | [diff] [blame] | 581 | |
| 582 | class KernelUpdater(RawPartitionUpdater): |
| 583 | """A class to update the kernel partition on a Chromium OS device.""" |
| 584 | |
| 585 | def _GetPartitionName(self): |
| 586 | """See RawPartitionUpdater._GetPartitionName().""" |
| 587 | return constants.PART_KERN_B |
| 588 | |
Amin Hassani | 0fe49ae | 2021-02-21 23:41:58 -0800 | [diff] [blame] | 589 | def _GetRemotePartitionName(self): |
| 590 | """See RawPartitionUpdater._GetRemotePartitionName().""" |
| 591 | return constants.QUICK_PROVISION_PAYLOAD_KERNEL |
| 592 | |
Amin Hassani | d684e98 | 2021-02-26 11:10:58 -0800 | [diff] [blame] | 593 | def Revert(self): |
| 594 | """Reverts the kernel partition update.""" |
| 595 | # There is nothing to do for reverting kernel partition. |
Amin Hassani | 75c5f94 | 2021-02-20 23:56:53 -0800 | [diff] [blame] | 596 | |
| 597 | |
| 598 | class RootfsUpdater(RawPartitionUpdater): |
| 599 | """A class to update the root partition on a Chromium OS device.""" |
| 600 | |
| 601 | def __init__(self, current_root: str, *args): |
| 602 | """Initializes the class. |
| 603 | |
| 604 | Args: |
| 605 | current_root: The current root device path. |
| 606 | *args: See PartitionUpdaterBase |
| 607 | """ |
| 608 | super().__init__(*args) |
| 609 | |
| 610 | self._current_root = current_root |
| 611 | self._ran_postinst = False |
| 612 | |
| 613 | def _GetPartitionName(self): |
| 614 | """See RawPartitionUpdater._GetPartitionName().""" |
| 615 | return constants.PART_ROOT_A |
| 616 | |
Amin Hassani | 0fe49ae | 2021-02-21 23:41:58 -0800 | [diff] [blame] | 617 | def _GetRemotePartitionName(self): |
| 618 | """See RawPartitionUpdater._GetRemotePartitionName().""" |
| 619 | return constants.QUICK_PROVISION_PAYLOAD_ROOTFS |
| 620 | |
Amin Hassani | 75c5f94 | 2021-02-20 23:56:53 -0800 | [diff] [blame] | 621 | def _Run(self): |
| 622 | """The function that does the job of rootfs partition update.""" |
| 623 | super()._Run() |
| 624 | |
| 625 | self._RunPostInst() |
| 626 | |
| 627 | def _OptimizePartLocation(self, offset: int, length: int): |
| 628 | """Optimizes the size of the root partition of the image. |
| 629 | |
| 630 | Normally the file system does not occupy the entire partition. Furthermore |
| 631 | we don't need the verity hash tree at the end of the root file system |
| 632 | because postinst will recreate it. This function reads the (approximate) |
| 633 | superblock of the ext4 partition and extracts the actual file system size in |
| 634 | the root partition. |
| 635 | """ |
| 636 | superblock_size = 4096 * 2 |
| 637 | with open(self._image, 'rb') as r: |
| 638 | r.seek(offset) |
| 639 | with tempfile.NamedTemporaryFile(delete=False) as fp: |
| 640 | fp.write(r.read(superblock_size)) |
| 641 | fp.close() |
| 642 | return offset, partition_lib.Ext2FileSystemSize(fp.name) |
| 643 | |
| 644 | def _RunPostInst(self, on_target: bool = True): |
| 645 | """Runs the postinst process in the root partition. |
| 646 | |
| 647 | Args: |
| 648 | on_target: If true the postinst is run on the target (inactive) |
| 649 | partition. This is used when doing normal updates. If false, the |
| 650 | postinst is run on the current (active) partition. This is used when |
| 651 | reverting an update. |
| 652 | """ |
| 653 | try: |
| 654 | postinst_dir = '/' |
| 655 | partition = self._current_root |
| 656 | if on_target: |
| 657 | postinst_dir = self._device.run( |
| 658 | ['mktemp', '-d', '-p', self._device.work_dir], |
| 659 | capture_output=True).stdout.strip() |
| 660 | self._device.run(['mount', '-o', 'ro', self._target, postinst_dir]) |
| 661 | partition = self._target |
| 662 | |
| 663 | self._ran_postinst = True |
| 664 | postinst = os.path.join(postinst_dir, 'postinst') |
| 665 | result = self._device.run([postinst, partition], capture_output=True) |
| 666 | |
| 667 | logging.debug('Postinst result on %s: \n%s', postinst, result.stdout) |
| 668 | logging.info('Postinstall completed.') |
| 669 | finally: |
| 670 | if on_target: |
| 671 | self._device.run(['umount', postinst_dir]) |
| 672 | |
| 673 | def Revert(self): |
| 674 | """Reverts the root update install.""" |
| 675 | logging.info('Reverting the rootfs partition update.') |
| 676 | if self._ran_postinst: |
| 677 | # We don't have to do anything for revert if we haven't changed the kernel |
| 678 | # priorities yet. |
| 679 | self._RunPostInst(on_target=False) |
Amin Hassani | 7440308 | 2021-02-22 11:40:09 -0800 | [diff] [blame^] | 680 | |
| 681 | |
| 682 | class StatefulPayloadGenerator(ReaderBase): |
| 683 | """A class for generating a stateful update payload in a separate thread.""" |
| 684 | def __init__(self, image: str): |
| 685 | """Initializes that class. |
| 686 | |
| 687 | Args: |
| 688 | image: The path to a local Chromium OS image. |
| 689 | """ |
| 690 | super().__init__() |
| 691 | self._image = image |
| 692 | |
| 693 | def run(self): |
| 694 | """Generates the stateful update and writes it into the output pipe.""" |
| 695 | try: |
| 696 | paygen_stateful_payload_lib.GenerateStatefulPayload( |
| 697 | self._image, self._Source()) |
| 698 | finally: |
| 699 | self._CloseSource() |
| 700 | |
| 701 | |
| 702 | class StatefulUpdater(PartitionUpdaterBase): |
| 703 | """A class to update the stateful partition on a device.""" |
| 704 | def __init__(self, clobber_stateful: bool, *args): |
| 705 | """Initializes the class |
| 706 | |
| 707 | Args: |
| 708 | clobber_stateful: Whether to clobber the stateful or not. |
| 709 | *args: Look at PartitionUpdaterBase. |
| 710 | """ |
| 711 | super().__init__(*args) |
| 712 | self._clobber_stateful = clobber_stateful |
| 713 | |
| 714 | def _Run(self): |
| 715 | """Reads/Downloads the stateful updates and writes it into the device.""" |
| 716 | if self._image_type == ImageType.FULL: |
| 717 | generator_cls = StatefulPayloadGenerator |
| 718 | elif self._image_type == ImageType.REMOTE_DIRECTORY: |
| 719 | generator_cls = GsFileCopier |
| 720 | self._image = os.path.join(self._image, |
| 721 | paygen_stateful_payload_lib.STATEFUL_FILE) |
| 722 | else: |
| 723 | raise ValueError(f'Invalid image type {self._image_type}') |
| 724 | |
| 725 | with generator_cls(self._image) as generator: |
| 726 | try: |
| 727 | updater = stateful_updater.StatefulUpdater(self._device) |
| 728 | updater.Update( |
| 729 | generator.Target(), |
| 730 | is_payload_on_device=False, |
| 731 | update_type=(stateful_updater.StatefulUpdater.UPDATE_TYPE_CLOBBER if |
| 732 | self._clobber_stateful else None)) |
| 733 | finally: |
| 734 | generator.CloseTarget() |
| 735 | |
| 736 | def Revert(self): |
| 737 | """Reverts the stateful partition update.""" |
| 738 | logging.info('Reverting the stateful update.') |
| 739 | stateful_updater.StatefulUpdater(self._device).Reset() |