Current File : /www/varak.net/nextcloud.varak.net/apps/encryption/lib/Command/FixEncryptedVersion.php
<?php
/**
* SPDX-FileCopyrightText: 2021-2024 Nextcloud GmbH and Nextcloud contributors
* SPDX-FileCopyrightText: 2019 ownCloud GmbH
* SPDX-License-Identifier: AGPL-3.0-only
*/
namespace OCA\Encryption\Command;
use OC\Files\Storage\Wrapper\Encryption;
use OC\Files\View;
use OC\ServerNotAvailableException;
use OCA\Encryption\Util;
use OCP\Files\IRootFolder;
use OCP\HintException;
use OCP\IConfig;
use OCP\IUser;
use OCP\IUserManager;
use Psr\Log\LoggerInterface;
use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputArgument;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;
class FixEncryptedVersion extends Command {
private bool $supportLegacy;
public function __construct(
private IConfig $config,
private LoggerInterface $logger,
private IRootFolder $rootFolder,
private IUserManager $userManager,
private Util $util,
private View $view,
) {
$this->supportLegacy = false;
parent::__construct();
}
protected function configure(): void {
parent::configure();
$this
->setName('encryption:fix-encrypted-version')
->setDescription('Fix the encrypted version if the encrypted file(s) are not downloadable.')
->addArgument(
'user',
InputArgument::OPTIONAL,
'The id of the user whose files need fixing'
)->addOption(
'path',
'p',
InputOption::VALUE_REQUIRED,
'Limit files to fix with path, e.g., --path="/Music/Artist". If path indicates a directory, all the files inside directory will be fixed.'
)->addOption(
'all',
null,
InputOption::VALUE_NONE,
'Run the fix for all users on the system, mutually exclusive with specifying a user id.'
);
}
protected function execute(InputInterface $input, OutputInterface $output): int {
$skipSignatureCheck = $this->config->getSystemValueBool('encryption_skip_signature_check', false);
$this->supportLegacy = $this->config->getSystemValueBool('encryption.legacy_format_support', false);
if ($skipSignatureCheck) {
$output->writeln("<error>Repairing is not possible when \"encryption_skip_signature_check\" is set. Please disable this flag in the configuration.</error>\n");
return 1;
}
if (!$this->util->isMasterKeyEnabled()) {
$output->writeln("<error>Repairing only works with master key encryption.</error>\n");
return 1;
}
$user = $input->getArgument('user');
$all = $input->getOption('all');
$pathOption = \trim(($input->getOption('path') ?? ''), '/');
if ($user) {
if ($all) {
$output->writeln("Specifying a user id and --all are mutually exclusive");
return 1;
}
if ($this->userManager->get($user) === null) {
$output->writeln("<error>User id $user does not exist. Please provide a valid user id</error>");
return 1;
}
return $this->runForUser($user, $pathOption, $output);
} elseif ($all) {
$result = 0;
$this->userManager->callForSeenUsers(function (IUser $user) use ($pathOption, $output, &$result) {
$output->writeln("Processing files for " . $user->getUID());
$result = $this->runForUser($user->getUID(), $pathOption, $output);
return $result === 0;
});
return $result;
} else {
$output->writeln("Either a user id or --all needs to be provided");
return 1;
}
}
private function runForUser(string $user, string $pathOption, OutputInterface $output): int {
$pathToWalk = "/$user/files";
if ($pathOption !== "") {
$pathToWalk = "$pathToWalk/$pathOption";
}
return $this->walkPathOfUser($user, $pathToWalk, $output);
}
/**
* @return int 0 for success, 1 for error
*/
private function walkPathOfUser(string $user, string $path, OutputInterface $output): int {
$this->setupUserFs($user);
if (!$this->view->file_exists($path)) {
$output->writeln("<error>Path \"$path\" does not exist. Please provide a valid path.</error>");
return 1;
}
if ($this->view->is_file($path)) {
$output->writeln("Verifying the content of file \"$path\"");
$this->verifyFileContent($path, $output);
return 0;
}
$directories = [];
$directories[] = $path;
while ($root = \array_pop($directories)) {
$directoryContent = $this->view->getDirectoryContent($root);
foreach ($directoryContent as $file) {
$path = $root . '/' . $file['name'];
if ($this->view->is_dir($path)) {
$directories[] = $path;
} else {
$output->writeln("Verifying the content of file \"$path\"");
$this->verifyFileContent($path, $output);
}
}
}
return 0;
}
/**
* @param bool $ignoreCorrectEncVersionCall, setting this variable to false avoids recursion
*/
private function verifyFileContent(string $path, OutputInterface $output, bool $ignoreCorrectEncVersionCall = true): bool {
try {
// since we're manually poking around the encrypted state we need to ensure that this isn't cached in the encryption wrapper
$mount = $this->view->getMount($path);
$storage = $mount->getStorage();
if ($storage && $storage->instanceOfStorage(Encryption::class)) {
$storage->clearIsEncryptedCache();
}
/**
* In encryption, the files are read in a block size of 8192 bytes
* Read block size of 8192 and a bit more (808 bytes)
* If there is any problem, the first block should throw the signature
* mismatch error. Which as of now, is enough to proceed ahead to
* correct the encrypted version.
*/
$handle = $this->view->fopen($path, 'rb');
if ($handle === false) {
$output->writeln("<warning>Failed to open file: \"$path\" skipping</warning>");
return true;
}
if (\fread($handle, 9001) !== false) {
$fileInfo = $this->view->getFileInfo($path);
if (!$fileInfo) {
$output->writeln("<warning>File info not found for file: \"$path\"</warning>");
return true;
}
$encryptedVersion = $fileInfo->getEncryptedVersion();
$stat = $this->view->stat($path);
if (($encryptedVersion == 0) && isset($stat['hasHeader']) && ($stat['hasHeader'] == true)) {
// The file has encrypted to false but has an encryption header
if ($ignoreCorrectEncVersionCall === true) {
// Lets rectify the file by correcting encrypted version
$output->writeln("<info>Attempting to fix the path: \"$path\"</info>");
return $this->correctEncryptedVersion($path, $output);
}
return false;
}
$output->writeln("<info>The file \"$path\" is: OK</info>");
}
\fclose($handle);
return true;
} catch (ServerNotAvailableException $e) {
// not a "bad signature" error and likely "legacy cipher" exception
// this could mean that the file is maybe not encrypted but the encrypted version is set
if (!$this->supportLegacy && $ignoreCorrectEncVersionCall === true) {
$output->writeln("<info>Attempting to fix the path: \"$path\"</info>");
return $this->correctEncryptedVersion($path, $output, true);
}
return false;
} catch (HintException $e) {
$this->logger->warning("Issue: " . $e->getMessage());
// If allowOnce is set to false, this becomes recursive.
if ($ignoreCorrectEncVersionCall === true) {
// Lets rectify the file by correcting encrypted version
$output->writeln("<info>Attempting to fix the path: \"$path\"</info>");
return $this->correctEncryptedVersion($path, $output);
}
return false;
}
}
/**
* @param bool $includeZero whether to try zero version for unencrypted file
*/
private function correctEncryptedVersion(string $path, OutputInterface $output, bool $includeZero = false): bool {
$fileInfo = $this->view->getFileInfo($path);
if (!$fileInfo) {
$output->writeln("<warning>File info not found for file: \"$path\"</warning>");
return true;
}
$fileId = $fileInfo->getId();
if ($fileId === null) {
$output->writeln("<warning>File info contains no id for file: \"$path\"</warning>");
return true;
}
$encryptedVersion = $fileInfo->getEncryptedVersion();
$wrongEncryptedVersion = $encryptedVersion;
$storage = $fileInfo->getStorage();
$cache = $storage->getCache();
$fileCache = $cache->get($fileId);
if (!$fileCache) {
$output->writeln("<warning>File cache entry not found for file: \"$path\"</warning>");
return true;
}
if ($storage->instanceOfStorage('OCA\Files_Sharing\ISharedStorage')) {
$output->writeln("<info>The file: \"$path\" is a share. Please also run the script for the owner of the share</info>");
return true;
}
// Save original encrypted version so we can restore it if decryption fails with all version
$originalEncryptedVersion = $encryptedVersion;
if ($encryptedVersion >= 0) {
if ($includeZero) {
// try with zero first
$cacheInfo = ['encryptedVersion' => 0, 'encrypted' => 0];
$cache->put($fileCache->getPath(), $cacheInfo);
$output->writeln("<info>Set the encrypted version to 0 (unencrypted)</info>");
if ($this->verifyFileContent($path, $output, false) === true) {
$output->writeln("<info>Fixed the file: \"$path\" with version 0 (unencrypted)</info>");
return true;
}
}
// Test by decrementing the value till 1 and if nothing works try incrementing
$encryptedVersion--;
while ($encryptedVersion > 0) {
$cacheInfo = ['encryptedVersion' => $encryptedVersion, 'encrypted' => $encryptedVersion];
$cache->put($fileCache->getPath(), $cacheInfo);
$output->writeln("<info>Decrement the encrypted version to $encryptedVersion</info>");
if ($this->verifyFileContent($path, $output, false) === true) {
$output->writeln("<info>Fixed the file: \"$path\" with version " . $encryptedVersion . "</info>");
return true;
}
$encryptedVersion--;
}
// So decrementing did not work. Now lets increment. Max increment is till 5
$increment = 1;
while ($increment <= 5) {
/**
* The wrongEncryptedVersion would not be incremented so nothing to worry about here.
* Only the newEncryptedVersion is incremented.
* For example if the wrong encrypted version is 4 then
* cycle1 -> newEncryptedVersion = 5 ( 4 + 1)
* cycle2 -> newEncryptedVersion = 6 ( 4 + 2)
* cycle3 -> newEncryptedVersion = 7 ( 4 + 3)
*/
$newEncryptedVersion = $wrongEncryptedVersion + $increment;
$cacheInfo = ['encryptedVersion' => $newEncryptedVersion, 'encrypted' => $newEncryptedVersion];
$cache->put($fileCache->getPath(), $cacheInfo);
$output->writeln("<info>Increment the encrypted version to $newEncryptedVersion</info>");
if ($this->verifyFileContent($path, $output, false) === true) {
$output->writeln("<info>Fixed the file: \"$path\" with version " . $newEncryptedVersion . "</info>");
return true;
}
$increment++;
}
}
$cacheInfo = ['encryptedVersion' => $originalEncryptedVersion, 'encrypted' => $originalEncryptedVersion];
$cache->put($fileCache->getPath(), $cacheInfo);
$output->writeln("<info>No fix found for \"$path\", restored version to original: $originalEncryptedVersion</info>");
return false;
}
/**
* Setup user file system
*/
private function setupUserFs(string $uid): void {
\OC_Util::tearDownFS();
\OC_Util::setupFS($uid);
}
}
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