Corrupt encrypted files cannot be deleted anymore

[BlackEdder0815]

Steps to reproduce

1. create an encrypted file (on an external storage)
2. modify this file directly (not through nextcloud) or provoke a corrupt write of the file
3. The file cannot opened by nextcloud anymore
4. The file cannot be deleted anymore (while trashbin-app is activated)

Expected behaviour

The corrupt file can be deleted, to clean-up the corrupted files.

Actual behaviour

There is no way to delete this file or the parent directory. (with activated trashbin-app)

Server configuration

Operating system: debian

Web server: unknown

Database: mysql

PHP version: 7.0.14

Nextcloud version: 11.0.1

Updated from an older Nextcloud/ownCloud or fresh install:
update from 11.0.0

Where did you install Nextcloud from:
setup-script, downloaded by nextcloud

Signing status:

Signing status

No errors have been found.

List of activated apps:

App list

 [2] =>   - activity: 2.4.1
    [3] =>   - audioplayer: 1.4.1
    [4] =>   - calendar: 1.5.0
    [5] =>   - comments: 1.1.0
    [6] =>   - contacts: 1.5.3
    [7] =>   - dav: 1.1.1
    [8] =>   - encryption: 1.4.1
    [9] =>   - federatedfilesharing: 1.1.1
    [10] =>   - federation: 1.1.1
    [11] =>   - files: 1.6.1
    [12] =>   - files_external: 1.1.2
    [13] =>   - files_external_acd: 0.1.3
    [14] =>   - files_pdfviewer: 1.0.1
    [15] =>   - files_sharing: 1.1.1
    [16] =>   - files_texteditor: 2.2
    [17] =>   - files_versions: 1.4.0
    [18] =>   - files_videoplayer: 1.0.0
    [19] =>   - firstrunwizard: 2.0
    [20] =>   - gallery: 16.0.0
    [21] =>   - logreader: 2.0.0
    [22] =>   - lookup_server_connector: 1.0.0
    [23] =>   - mail: 0.6.2
    [24] =>   - nextcloud_announcements: 1.0
    [25] =>   - notifications: 1.0.1
    [26] =>   - password_policy: 1.1.0
    [27] =>   - provisioning_api: 1.1.0
    [28] =>   - serverinfo: 1.1.1
    [29] =>   - sharebymail: 1.0.1
    [30] =>   - survey_client: 0.1.5
    [31] =>   - systemtags: 1.1.3
    [32] =>   - theming: 1.1.1
    [33] =>   - twofactor_backupcodes: 1.0.0
    [34] =>   - updatenotification: 1.1.1
    [35] =>   - workflowengine: 1.1.1

The content of config/config.php:

Config report

$CONFIG = array (
'instanceid' => 'xxx',
'passwordsalt' => 'xxx',
'secret' => 'xxx',
'trusted_domains' =>
array (
0 => 'xxx',
),
'datadirectory' => '/www/htdocs/xxx/cloud/data',
'overwrite.cli.url' => 'https://xxx',
'dbtype' => 'mysql',
'version' => '11.0.1.2',
'dbname' => 'xxx',
'dbhost' => 'localhost',
'dbport' => '',
'dbtableprefix' => 'oc_',
'dbuser' => 'xxx',
'dbpassword' => 'xxx',
'logtimezone' => 'UTC',
'installed' => true,
'enable_previews' => true,
'preview_max_x' => 1024,
'preview_max_y' => 1024,
'preview_max_scale_factor' => 10,
'preview_max_filesize_image' => 50,
'preview_libreoffice_path' => '/usr/bin/libreoffice',
'preview_office_cl_parameters' => ' --headless --nologo --nofirststartwizard --invisible --norestore --convert-to pdf --outdir ',
'enabledPreviewProviders' =>
array (
0 => 'OC\\Preview\\PNG',
1 => 'OC\\Preview\\JPEG',
2 => 'OC\\Preview\\GIF',
3 => 'OC\\Preview\\BMP',
4 => 'OC\\Preview\\XBitmap',
5 => 'OC\\Preview\\TXT',
6 => 'OC\\Preview\\MarkDown',
),
'maintenance' => false,
'theme' => '',
'loglevel' => 2,
'tempdirectory' => '/www/htdocs/xxx/cloud/data/tmp/',
);

Are you using external storage, if yes which one: acd

Are you using encryption: yes

Are you using an external user-backend, if yes which one: no

Client configuration

Browser: Firefox

Operating system: Windows 7

Logs

Web server error log

Web server error log

no access to this log

Nextcloud log (data/nextcloud.log)

Nextcloud log

> 	OC\HintException: Bad Signature
> /www/htdocs/w015300e/cloud/apps/encryption/lib/Crypto/Crypt.php - line 464: OCA\Encryption\Crypto\Crypt->checkSignature('OfpNiCWq3LdUZ0t...', 't\x06R\xDB\x88\x92\x17\x92\x84\xD5\xD7\x19\xB4\x1ED...', '67eaa49887ea0a3...')
> /www/htdocs/w015300e/cloud/apps/encryption/lib/Crypto/Encryption.php - line 372: OCA\Encryption\Crypto\Crypt->symmetricDecryptFileContent('OfpNiCWq3LdUZ0t...', 't\x06R\xDB\x88\x92\x17\x92\x84\xD5\xD7\x19\xB4\x1ED...', 'AES-256-CTR', 0, 0)
> /www/htdocs/w015300e/cloud/lib/private/Files/Stream/Encryption.php - line 460: OCA\Encryption\Crypto\Encryption->decrypt('OfpNiCWq3LdUZ0t...', 0)
> /www/htdocs/w015300e/cloud/lib/private/Files/Stream/Encryption.php - line 291: OC\Files\Stream\Encryption->readCache()
> [internal function] OC\Files\Stream\Encryption->stream_read(8192)
> /www/htdocs/w015300e/cloud/lib/private/legacy/helper.php - line 296: fread(Resource id #1046, 8192)
> /www/htdocs/w015300e/cloud/lib/private/Files/Storage/Wrapper/Encryption.php - line 745: OC_Helper streamCopy(Resource id #1046, Resource id #1047)
> /www/htdocs/w015300e/cloud/lib/private/Files/Storage/Wrapper/Encryption.php - line 642: OC\Files\Storage\Wrapper\Encryption->copyBetweenStorage(Object(OCA\Files_Trashbin\Storage), 'Musik/Sunshine ...', 'files_trashbin/...', false, true)
> /www/htdocs/w015300e/cloud/lib/private/Files/Storage/Wrapper/Encryption.php - line 737: OC\Files\Storage\Wrapper\Encryption->copyFromStorage(Object(OCA\Files_Trashbin\Storage), 'Musik/Sunshine ...', 'files_trashbin/...', false, true)
> /www/htdocs/w015300e/cloud/lib/private/Files/Storage/Wrapper/Encryption.php - line 614: OC\Files\Storage\Wrapper\Encryption->copyBetweenStorage(Object(OCA\Files_Trashbin\Storage), 'Musik/Sunshine ...', 'files_trashbin/...', true, true)
> /www/htdocs/w015300e/cloud/lib/private/Files/Storage/Wrapper/Wrapper.php - line 569: OC\Files\Storage\Wrapper\Encryption->moveFromStorage(Object(OCA\Files_Trashbin\Storage), 'Musik/Sunshine ...', 'files_trashbin/...')
> /www/htdocs/w015300e/cloud/apps/files_trashbin/lib/Trashbin.php - line 237: OC\Files\Storage\Wrapper\Wrapper->moveFromStorage(Object(OCA\Files_Trashbin\Storage), 'Musik/Sunshine ...', 'files_trashbin/...')
> /www/htdocs/w015300e/cloud/apps/files_trashbin/lib/Storage.php - line 161: OCA\Files_Trashbin\Trashbin move2trash('ACD/Musik/Sunsh...')
> /www/htdocs/w015300e/cloud/apps/files_trashbin/lib/Storage.php - line 107: OCA\Files_Trashbin\Storage->doDelete('Musik/Sunshine ...', 'rmdir')
> /www/htdocs/w015300e/cloud/lib/private/Files/View.php - line 1124: OCA\Files_Trashbin\Storage->rmdir('Musik/Sunshine ...')
> /www/htdocs/w015300e/cloud/lib/private/Files/View.php - line 345: OC\Files\View->basicOperation('rmdir', '/ACD/Musik/Suns...', Array)
> /www/htdocs/w015300e/cloud/apps/dav/lib/Connector/Sabre/Directory.php - line 277: OC\Files\View->rmdir('/ACD/Musik/Suns...')
> /www/htdocs/w015300e/cloud/3rdparty/sabre/dav/lib/DAV/Tree.php - line 179: OCA\DAV\Connector\Sabre\Directory->delete()
> /www/htdocs/w015300e/cloud/3rdparty/sabre/dav/lib/DAV/CorePlugin.php - line 287: Sabre\DAV\Tree->delete('ACD/Musik/Sunsh...')
> [internal function] Sabre\DAV\CorePlugin->httpDelete(Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response))
> /www/htdocs/w015300e/cloud/3rdparty/sabre/event/lib/EventEmitterTrait.php - line 105: call_user_func_array(Array, Array)
> /www/htdocs/w015300e/cloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 479: Sabre\Event\EventEmitter->emit('method DELETE', Array)
> /www/htdocs/w015300e/cloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 254: Sabre\DAV\Server->invokeMethod(Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response))
> /www/htdocs/w015300e/cloud/apps/dav/appinfo/v1/webdav.php - line 60: Sabre\DAV\Server->exec()
> /www/htdocs/w015300e/cloud/remote.php - line 165: require_once('/www/htdocs/w01...')
> {main}```
</details>

#### Browser log
<details>
<summary>Browser log</summary>

nothing relevant

</details>

[BlackEdder0815]

See https://help.nextcloud.com/t/cannot-delete-corrupted-encrypted-file-bad-signature/9224

[nickvergessen]

@schiessle

[schiessle]

I just tried it but couldn't reproduce it. Is there anything else worth mentioning? Is the file (parent folder) shared? Do you use external storages?

[schiessle]

@BlackEdder0815 even if I couldn't reproduce it completely (I could trigger a error message in case of shared files but the file was still deleted) I have a idea what caused the problem. This PR should fix it, maybe you can test it: #3841

[BlackEdder0815]

Sounds good, thank you. I check this out, when it will be released with the next version.
The code-change looks quite good.
Thank you for the fix!!!