498 lines
13 KiB
PHP
498 lines
13 KiB
PHP
<?php
|
|
|
|
/**
|
|
* ownCloud
|
|
*
|
|
* @author Sam Tuke, Robin Appelman
|
|
* @copyright 2012 Sam Tuke samtuke@owncloud.com, Robin Appelman
|
|
* icewind1991@gmail.com
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
|
|
* License as published by the Free Software Foundation; either
|
|
* version 3 of the License, or any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
|
|
*
|
|
* You should have received a copy of the GNU Affero General Public
|
|
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*/
|
|
|
|
/**
|
|
* @brief Encryption proxy which handles filesystem operations before and after
|
|
* execution and encrypts, and handles keyfiles accordingly. Used for
|
|
* webui.
|
|
*/
|
|
|
|
namespace OCA\Encryption;
|
|
|
|
class Proxy extends \OC_FileProxy {
|
|
|
|
private static $blackList = null; //mimetypes blacklisted from encryption
|
|
|
|
private static $enableEncryption = null;
|
|
|
|
/**
|
|
* Check if a file requires encryption
|
|
* @param string $path
|
|
* @return bool
|
|
*
|
|
* Tests if server side encryption is enabled, and file is allowed by blacklists
|
|
*/
|
|
private static function shouldEncrypt( $path ) {
|
|
|
|
if ( is_null( self::$enableEncryption ) ) {
|
|
|
|
if (
|
|
\OCP\Config::getAppValue( 'files_encryption', 'enable_encryption', 'true' ) == 'true'
|
|
&& Crypt::mode() == 'server'
|
|
) {
|
|
|
|
self::$enableEncryption = true;
|
|
|
|
} else {
|
|
|
|
self::$enableEncryption = false;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if ( !self::$enableEncryption ) {
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
if ( is_null(self::$blackList ) ) {
|
|
|
|
self::$blackList = explode(',', \OCP\Config::getAppValue( 'files_encryption', 'type_blacklist', '' ) );
|
|
|
|
}
|
|
|
|
if ( Crypt::isCatfileContent( $path ) ) {
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
$extension = substr( $path, strrpos( $path, '.' ) +1 );
|
|
|
|
if ( array_search( $extension, self::$blackList ) === false ) {
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
public function preFile_put_contents( $path, &$data ) {
|
|
|
|
if ( self::shouldEncrypt( $path ) ) {
|
|
|
|
// Stream put contents should have been converted to fopen
|
|
if ( !is_resource( $data ) ) {
|
|
|
|
$userId = \OCP\USER::getUser();
|
|
$view = new \OC_FilesystemView( '/' );
|
|
$util = new Util( $view, $userId );
|
|
$session = new Session( $view );
|
|
$privateKey = $session->getPrivateKey();
|
|
$filePath = $util->stripUserFilesPath( $path );
|
|
// Set the filesize for userland, before encrypting
|
|
$size = strlen( $data );
|
|
|
|
// Disable encryption proxy to prevent recursive calls
|
|
$proxyStatus = \OC_FileProxy::$enabled;
|
|
\OC_FileProxy::$enabled = false;
|
|
|
|
// Check if there is an existing key we can reuse
|
|
if ( $encKeyfile = Keymanager::getFileKey( $view, $userId, $filePath ) ) {
|
|
|
|
// Fetch shareKey
|
|
$shareKey = Keymanager::getShareKey( $view, $userId, $filePath );
|
|
|
|
// Decrypt the keyfile
|
|
$plainKey = Crypt::multiKeyDecrypt( $encKeyfile, $shareKey, $privateKey );
|
|
|
|
} else {
|
|
|
|
// Make a new key
|
|
$plainKey = Crypt::generateKey();
|
|
|
|
}
|
|
|
|
// Encrypt data
|
|
$encData = Crypt::symmetricEncryptFileContent( $data, $plainKey );
|
|
|
|
$sharingEnabled = \OCP\Share::isEnabled();
|
|
|
|
$uniqueUserIds = $util->getSharingUsersArray( $sharingEnabled, $filePath, $userId );
|
|
|
|
// Fetch public keys for all users who will share the file
|
|
$publicKeys = Keymanager::getPublicKeys( $view, $uniqueUserIds );
|
|
|
|
// Encrypt plain keyfile to multiple sharefiles
|
|
$multiEncrypted = Crypt::multiKeyEncrypt( $plainKey, $publicKeys );
|
|
|
|
// Save sharekeys to user folders
|
|
Keymanager::setShareKeys( $view, $filePath, $multiEncrypted['keys'] );
|
|
|
|
// Set encrypted keyfile as common varname
|
|
$encKey = $multiEncrypted['data'];
|
|
|
|
// Save keyfile for newly encrypted file in parallel directory tree
|
|
Keymanager::setFileKey( $view, $filePath, $userId, $encKey );
|
|
|
|
// Replace plain content with encrypted content by reference
|
|
$data = $encData;
|
|
|
|
// Update the file cache with file info
|
|
\OC\Files\Filesystem::putFileInfo( $filePath, array( 'encrypted'=>true, 'size' => strlen($size), 'unencrypted_size' => $size), '' );
|
|
|
|
// Re-enable proxy - our work is done
|
|
\OC_FileProxy::$enabled = $proxyStatus;
|
|
|
|
}
|
|
}
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
/**
|
|
* @param string $path Path of file from which has been read
|
|
* @param string $data Data that has been read from file
|
|
*/
|
|
public function postFile_get_contents( $path, $data ) {
|
|
|
|
// FIXME: $path for shared files is just /uid/files/Shared/filepath
|
|
|
|
$userId = \OCP\USER::getUser();
|
|
$view = new \OC_FilesystemView( '/' );
|
|
$util = new Util( $view, $userId );
|
|
|
|
$relPath = $util->stripUserFilesPath( $path );
|
|
|
|
|
|
// TODO check for existing key file and reuse it if possible to avoid problems with versioning etc.
|
|
// Disable encryption proxy to prevent recursive calls
|
|
$proxyStatus = \OC_FileProxy::$enabled;
|
|
\OC_FileProxy::$enabled = false;
|
|
|
|
// If data is a catfile
|
|
if (
|
|
Crypt::mode() == 'server'
|
|
&& Crypt::isCatfileContent( $data ) // TODO: Do we really need this check? Can't we assume it is properly encrypted?
|
|
) {
|
|
|
|
// TODO: use get owner to find correct location of key files for shared files
|
|
$session = new Session( $view );
|
|
$privateKey = $session->getPrivateKey( $userId );
|
|
|
|
// Get the encrypted keyfile
|
|
$encKeyfile = Keymanager::getFileKey( $view, $userId, $relPath );
|
|
|
|
// Attempt to fetch the user's shareKey
|
|
$shareKey = Keymanager::getShareKey( $view, $userId, $relPath );
|
|
|
|
// Decrypt keyfile with shareKey
|
|
$plainKeyfile = Crypt::multiKeyDecrypt( $encKeyfile, $shareKey, $privateKey );
|
|
|
|
$plainData = Crypt::symmetricDecryptFileContent( $data, $plainKeyfile );
|
|
|
|
} elseif (
|
|
Crypt::mode() == 'server'
|
|
&& isset( $_SESSION['legacyenckey'] )
|
|
&& Crypt::isEncryptedMeta( $path )
|
|
) {
|
|
|
|
$plainData = Crypt::legacyDecrypt( $data, $session->getLegacyKey() );
|
|
|
|
}
|
|
|
|
\OC_FileProxy::$enabled = $proxyStatus;
|
|
|
|
if ( ! isset( $plainData ) ) {
|
|
|
|
$plainData = $data;
|
|
|
|
}
|
|
|
|
return $plainData;
|
|
|
|
}
|
|
|
|
/**
|
|
* @brief When a file is deleted, remove its keyfile also
|
|
*/
|
|
public function preUnlink( $path ) {
|
|
|
|
// let the trashbin handle this
|
|
if ( \OCP\App::isEnabled('files_trashbin') ) {
|
|
return true;
|
|
}
|
|
|
|
// Disable encryption proxy to prevent recursive calls
|
|
$proxyStatus = \OC_FileProxy::$enabled;
|
|
\OC_FileProxy::$enabled = false;
|
|
|
|
$view = new \OC_FilesystemView( '/' );
|
|
|
|
$userId = \OCP\USER::getUser();
|
|
|
|
$util = new Util( $view, $userId );
|
|
|
|
// Format path to be relative to user files dir
|
|
$relPath = $util->stripUserFilesPath( $path );
|
|
|
|
list( $owner, $ownerPath ) = $util->getUidAndFilename( $relPath );
|
|
|
|
// Delete keyfile & shareKey so it isn't orphaned
|
|
if (
|
|
! (
|
|
Keymanager::deleteFileKey( $view, $owner, $ownerPath )
|
|
&& Keymanager::delAllShareKeys( $view, $owner, $ownerPath )
|
|
)
|
|
) {
|
|
|
|
\OC_Log::write( 'Encryption library', 'Keyfile or shareKey could not be deleted for file "'.$ownerPath.'"', \OC_Log::ERROR );
|
|
|
|
}
|
|
|
|
\OC_FileProxy::$enabled = $proxyStatus;
|
|
|
|
// If we don't return true then file delete will fail; better
|
|
// to leave orphaned keyfiles than to disallow file deletion
|
|
return true;
|
|
|
|
}
|
|
|
|
/**
|
|
* @brief When a file is renamed, rename its keyfile also
|
|
* @return bool Result of rename()
|
|
* @note This is pre rather than post because using post didn't work
|
|
*/
|
|
public function postWrite( $path )
|
|
{
|
|
$this->handleFile($path);
|
|
|
|
return true;
|
|
}
|
|
|
|
public function postTouch( $path )
|
|
{
|
|
$this->handleFile($path);
|
|
|
|
return true;
|
|
}
|
|
|
|
public function postFopen( $path, &$result ){
|
|
|
|
if ( !$result ) {
|
|
|
|
return $result;
|
|
|
|
}
|
|
|
|
// Reformat path for use with OC_FSV
|
|
$path_split = explode( '/', $path );
|
|
$path_f = implode( '/', array_slice( $path_split, 3 ) );
|
|
|
|
// FIXME: handling for /userId/cache used by webdav for chunking. The cache chunks are NOT encrypted
|
|
if($path_split[2] == 'cache') {
|
|
return $result;
|
|
}
|
|
|
|
// Disable encryption proxy to prevent recursive calls
|
|
$proxyStatus = \OC_FileProxy::$enabled;
|
|
\OC_FileProxy::$enabled = false;
|
|
|
|
$meta = stream_get_meta_data( $result );
|
|
|
|
$view = new \OC_FilesystemView( '' );
|
|
|
|
$util = new Util( $view, \OCP\USER::getUser());
|
|
|
|
// If file is already encrypted, decrypt using crypto protocol
|
|
if (
|
|
Crypt::mode() == 'server'
|
|
&& $util->isEncryptedPath( $path )
|
|
) {
|
|
|
|
// Close the original encrypted file
|
|
fclose( $result );
|
|
|
|
// Open the file using the crypto stream wrapper
|
|
// protocol and let it do the decryption work instead
|
|
$result = fopen( 'crypt://' . $path_f, $meta['mode'] );
|
|
|
|
|
|
} elseif (
|
|
self::shouldEncrypt( $path )
|
|
and $meta ['mode'] != 'r'
|
|
and $meta['mode'] != 'rb'
|
|
) {
|
|
// If the file is not yet encrypted, but should be
|
|
// encrypted when it's saved (it's not read only)
|
|
|
|
// NOTE: this is the case for new files saved via WebDAV
|
|
|
|
// if (
|
|
// $view->file_exists( $path )
|
|
// and $view->filesize( $path ) > 0
|
|
// ) {
|
|
// $x = $view->file_get_contents( $path );
|
|
//
|
|
// $tmp = tmpfile();
|
|
|
|
// // Make a temporary copy of the original file
|
|
// \OCP\Files::streamCopy( $result, $tmp );
|
|
//
|
|
// // Close the original stream, we'll return another one
|
|
// fclose( $result );
|
|
//
|
|
// $view->file_put_contents( $path_f, $tmp );
|
|
//
|
|
// fclose( $tmp );
|
|
|
|
// }
|
|
|
|
$result = fopen( 'crypt://'.$path_f, $meta['mode'] );
|
|
|
|
}
|
|
|
|
// Re-enable the proxy
|
|
\OC_FileProxy::$enabled = $proxyStatus;
|
|
|
|
return $result;
|
|
|
|
}
|
|
|
|
public function postGetMimeType( $path, $mime ) {
|
|
|
|
if ( Crypt::isCatfileContent( $path ) ) {
|
|
|
|
$mime = \OCP\Files::getMimeType( 'crypt://' . $path, 'w' );
|
|
|
|
}
|
|
|
|
return $mime;
|
|
|
|
}
|
|
|
|
public function postGetFileInfo( $path, $data ) {
|
|
|
|
// if path is a folder do nothing
|
|
if(is_array($data) && array_key_exists('size', $data)) {
|
|
|
|
// Disable encryption proxy to prevent recursive calls
|
|
$proxyStatus = \OC_FileProxy::$enabled;
|
|
\OC_FileProxy::$enabled = false;
|
|
|
|
// get file size
|
|
$data['size'] = self::postFileSize($path, $data['size']);
|
|
|
|
// Re-enable the proxy
|
|
\OC_FileProxy::$enabled = $proxyStatus;
|
|
}
|
|
|
|
return $data;
|
|
}
|
|
|
|
public function postStat($path, $data)
|
|
{
|
|
// check if file is encrypted
|
|
if (Crypt::isCatfileContent($path)) {
|
|
|
|
// get file info from cache
|
|
$cached = \OC\Files\Filesystem::getFileInfo($path, '');
|
|
|
|
// set the real file size
|
|
$data['size'] = $cached['unencrypted_size'];
|
|
}
|
|
|
|
return $data;
|
|
}
|
|
|
|
public function postFileSize($path, $size)
|
|
{
|
|
|
|
$view = new \OC_FilesystemView('/');
|
|
|
|
// if path is a folder do nothing
|
|
if ($view->is_dir($path)) {
|
|
return $size;
|
|
}
|
|
|
|
// Reformat path for use with OC_FSV
|
|
$path_split = explode('/', $path);
|
|
$path_f = implode('/', array_slice($path_split, 3));
|
|
|
|
// if path is empty we cannot resolve anything
|
|
if(empty($path_f)) {
|
|
return $size;
|
|
}
|
|
|
|
// get file info from database/cache
|
|
$fileInfo = \OC\Files\Filesystem::getFileInfo($path_f);
|
|
|
|
// if file is encrypted return real file size
|
|
if (is_array($fileInfo) && $fileInfo['encrypted'] === true) {
|
|
$size = $fileInfo['unencrypted_size'];
|
|
} else {
|
|
// self healing if file was removed from file cache
|
|
if(is_array($fileInfo)) {
|
|
$userId = \OCP\User::getUser();
|
|
$util = new Util( $view, $userId );
|
|
$fixSize = $util->getFileSize($path);
|
|
if($fixSize > 0) {
|
|
$size = $fixSize;
|
|
|
|
$fileInfo['encrypted'] = true;
|
|
$fileInfo['unencrypted_size'] = $size;
|
|
|
|
// put file info
|
|
$view->putFileInfo( $path_f, $fileInfo );
|
|
}
|
|
}
|
|
}
|
|
return $size;
|
|
}
|
|
|
|
public function handleFile($path) {
|
|
|
|
// Disable encryption proxy to prevent recursive calls
|
|
$proxyStatus = \OC_FileProxy::$enabled;
|
|
\OC_FileProxy::$enabled = false;
|
|
|
|
$view = new \OC_FilesystemView('/');
|
|
$session = new Session($view);
|
|
$userId = \OCP\User::getUser();
|
|
$util = new Util( $view, $userId );
|
|
|
|
// Reformat path for use with OC_FSV
|
|
$path_split = explode( '/', $path );
|
|
$path_f = implode( '/', array_slice( $path_split, 3 ) );
|
|
|
|
// only if file is on 'files' folder fix file size and sharing
|
|
if($path_split[2] == 'files' && $util->fixFileSize($path)) {
|
|
|
|
// get sharing app state
|
|
$sharingEnabled = \OCP\Share::isEnabled();
|
|
|
|
// get users
|
|
$usersSharing = $util->getSharingUsersArray($sharingEnabled, $path_f);
|
|
|
|
// update sharing-keys
|
|
$util->setSharedFileKeyfiles($session, $usersSharing, $path_f);
|
|
}
|
|
|
|
\OC_FileProxy::$enabled = $proxyStatus;
|
|
}
|
|
}
|