encryption Default Encryption Module Default encryption module for Nextcloud Server-side Encryption (SSE) 2.21.0 agpl Bjoern Schiessle Clark Tomlinson user-encryption admin-encryption files security https://github.com/nextcloud/server/issues openssl OCA\Encryption\Migration\SetMasterKeyStatus OCA\Encryption\Command\EnableMasterKey OCA\Encryption\Command\DisableMasterKey OCA\Encryption\Command\RecoverUser OCA\Encryption\Command\ScanLegacyFormat OCA\Encryption\Command\FixEncryptedVersion OCA\Encryption\Command\FixKeyLocation OCA\Encryption\Command\DropLegacyFileKey OCA\Encryption\Command\CleanOrphanedKeys OCA\Encryption\Settings\Admin OCA\Encryption\Settings\Personal