From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1D06CC2D0FB for ; Wed, 13 May 2020 03:07:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E900424927 for ; Wed, 13 May 2020 03:07:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589339227; bh=mf0A77JO/o1Mk6zUTHq9K+pvz3bYpz5zIclotccg+Fo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=stoiCbkWCYp5AnimBf9VtucIGxTPjiOhfIlNPhFjNPkCvtyfb667Q+pfXBNxKIgY1 fGHtUNB1NErVj9ItneP1swacdxR3f0otmJ/2LhTe7nPEkI3H+0nTquUt2d9UUiE+Jz 4L+P08zXf2jDBGwH8pQkA45fP+yS7x8A17m4dNNg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726347AbgEMDHG (ORCPT ); Tue, 12 May 2020 23:07:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:42612 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725898AbgEMDHG (ORCPT ); Tue, 12 May 2020 23:07:06 -0400 Received: from localhost (unknown [104.132.1.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A843D2176D; Wed, 13 May 2020 03:07:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589339225; bh=mf0A77JO/o1Mk6zUTHq9K+pvz3bYpz5zIclotccg+Fo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=yoPvoPvrtTgr0s5g4gLXEiIOsQf1dxfj/oBrrGa+nwoA6dE2mGMBtdWeohFt+yKvn 4KlSpBlNspt1Pg1OVOViCkzUUafX+woN5Q0mQkMWH2ysQ77USKFxfJNTgDaMtkx6hS UGIOguCPrp8uo1y+tI6zLJ6p8n4VHZjG9dmJvNI0= Date: Tue, 12 May 2020 20:07:05 -0700 From: Jaegeuk Kim To: "Theodore Y. Ts'o" Cc: Eric Biggers , linux-fscrypt@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Daniel Rosenberg Subject: Re: [PATCH 2/4] fscrypt: add fscrypt_add_test_dummy_key() Message-ID: <20200513030705.GB108075@google.com> References: <20200512233251.118314-1-ebiggers@kernel.org> <20200512233251.118314-3-ebiggers@kernel.org> <20200513005538.GF1596452@mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200513005538.GF1596452@mit.edu> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On 05/12, Theodore Y. Ts'o wrote: > On Tue, May 12, 2020 at 04:32:49PM -0700, Eric Biggers wrote: > > From: Eric Biggers > > > > Currently, the test_dummy_encryption mount option (which is used for > > encryption I/O testing with xfstests) uses v1 encryption policies, and > > it relies on userspace inserting a test key into the session keyring. > > > > We need test_dummy_encryption to support v2 encryption policies too. > > Requiring userspace to add the test key doesn't work well with v2 > > policies, since v2 policies only support the filesystem keyring (not the > > session keyring), and keys in the filesystem keyring are lost when the > > filesystem is unmounted. Hooking all test code that unmounts and > > re-mounts the filesystem would be difficult. > > > > Instead, let's make the filesystem automatically add the test key to its > > keyring when test_dummy_encryption is enabled. > > > > That puts the responsibility for choosing the test key on the kernel. > > We could just hard-code a key. But out of paranoia, let's first try > > using a per-boot random key, to prevent this code from being misused. > > A per-boot key will work as long as no one expects dummy-encrypted files > > to remain accessible after a reboot. (gce-xfstests doesn't.) > > > > Therefore, this patch adds a function fscrypt_add_test_dummy_key() which > > implements the above. The next patch will use it. > > > > Signed-off-by: Eric Biggers > > Reviewed-by: Theodore Ts'o Reviewed-by: Jaegeuk Kim