From patchwork Sun Jul 24 00:52:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sweet Tea Dorminy X-Patchwork-Id: 12927386 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4DFFACCA489 for ; Sun, 24 Jul 2022 00:52:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235349AbiGXAwj (ORCPT ); Sat, 23 Jul 2022 20:52:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36592 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229772AbiGXAwi (ORCPT ); Sat, 23 Jul 2022 20:52:38 -0400 Received: from box.fidei.email (box.fidei.email [71.19.144.250]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CE8C14D10; Sat, 23 Jul 2022 17:52:37 -0700 (PDT) Received: from authenticated-user (box.fidei.email [71.19.144.250]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by box.fidei.email (Postfix) with ESMTPSA id F0D6780794; Sat, 23 Jul 2022 20:52:36 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=dorminy.me; s=mail; t=1658623957; bh=RAQNqSLQnPCNoIiEhDvY+4M3GbpUGvsojzAKy+lc6/Q=; h=From:To:Cc:Subject:Date:From; b=SdCm/HZTzCERxBrSYy57Lv5VWfRalppRdv/RcLrb5LvH/4SvbnoLOQTa6tsbtZTzA +i0XYqbfWhLa6nv9RuHreGac2jT2kk+KuXfHxS9GDD7GTOeSlxxDt4DMd1HO/mXJlo kvrGJLi8cZBbnEyr9eq3qBp+CDv+oQ3x5BtlyXhUDDCAmZKwSBUnCAkzAJvhfhsn2r hZCyRq/kDhZexVvlxRFGdwuu/PFznInLCtPlI0vxZA3eolC2va8NY2MHJD2kVufbMm Mhx54KAz6/KKNc0m7t+0T6hyyUjF5dq2g3+doB+DxrJcH7yvsBFyvfyVY/uLoE0ABJ wshdUrn6QaeQQ== From: Sweet Tea Dorminy To: "Theodore Y . Ts'o " , Jaegeuk Kim , Eric Biggers , linux-fscrypt@vger.kernel.org, linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, osandov@osandov.com, kernel-team@fb.com Cc: Sweet Tea Dorminy Subject: [PATCH RFC 0/4] fscrypt changes for btrfs encryption Date: Sat, 23 Jul 2022 20:52:24 -0400 Message-Id: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is the fscrypt section of my draft patch series [1] to add encryption support to btrfs. Last October, Omar Sandoval sent out a design proposal for using fscrypt with btrfs [2]. To tersely summarize the challenges laid out in the document, btrfs supports sharing the same physical storage between multiple files (reflinks); moving the physical location of file data without access to the file inodes; and creating writable snapshots of some directories (subvolumes). To allow encryption to coexist with these features, the proposal was for btrfs to create and preserve an IV per data block, no matter its physical location or owning inode(s), and for btrfs to allow partially-encrypted writable snapshots of unencrypted subvolumes. To deal with these issues, a few changes to fscrypt are proposed: - To enable snapshotting and then encrypting new writes to that subvolume, a flag to allow partially encrypted directories; - To allow filesystems to supply an IV in cases where the logical block number and owning inode for data may change, a new policy and interface to convey IVs from filesystem to fscrypt. Comments, especially on the new policy and interface, appreciated! [1] https://lore.kernel.org/linux-btrfs/cover.1658623319.git.sweettea-kernel@dorminy.me [2] https://lore.kernel.org/linux-btrfs/YXGyq+buM79A1S0L@relinquished.localdomain/ Omar Sandoval (3): fscrypt: expose fscrypt_nokey_name fscrypt: add flag allowing partially-encrypted directories fscrypt: add fscrypt_have_same_policy() to check inode's compatibility Sweet Tea Dorminy (1): fscrypt: Add new encryption policy for btrfs. fs/crypto/crypto.c | 28 +++++++++++++++-- fs/crypto/fname.c | 56 ++++++++++----------------------- fs/crypto/fscrypt_private.h | 4 +-- fs/crypto/inline_crypt.c | 20 ++++++++---- fs/crypto/keysetup.c | 5 +++ fs/crypto/policy.c | 42 ++++++++++++++++++++++++- include/linux/fscrypt.h | 61 +++++++++++++++++++++++++++++++++++- include/uapi/linux/fscrypt.h | 1 + 8 files changed, 166 insertions(+), 51 deletions(-)