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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 2167FC4332D for ; Thu, 19 Mar 2020 20:19:42 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E6E66206D7 for ; Thu, 19 Mar 2020 20:19:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="dmnbJcwD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6E66206D7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mit.edu Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=AWLI55NpEuo5l5Pc63fR+bbhoLjlSlRptG0jfb+8bxc=; b=dmnbJcwDIJc3dx HTncbRiYYvprt8s3bQco47fJy77sYgjxNWy266fb/rkAqJCdRgMNfyZ5h+Y+eolfnnBZrJ4zuyybL XqPWIKRDWPzKBgwk6djEapiAhZ0q03IMEXuArTj4NwNr3e/zV8zB7x7JFBLCGGxdtTedoj/KBF5BS qsJU5Z1kU34n6WTYydg9iRZlk9gPB1BA3XvAcAXpqbjVNaIeCsrQtJVmEuRwHoe6NrC9z1y6tYCMn oe1KsWZzbabSVp2/5xm6uyQi+2TxV0IUG8JkOeaC97BlRXo1p1juLocPEUMkIKCOexNWLrU3eiuN5 pHdZcpwTcG+lC8LgnHqA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jF1dZ-0005FM-Tb; Thu, 19 Mar 2020 20:19:29 +0000 Received: from outgoing-auth-1.mit.edu ([18.9.28.11] helo=outgoing.mit.edu) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jF1dW-0005El-2w for linux-mtd@lists.infradead.org; Thu, 19 Mar 2020 20:19:27 +0000 Received: from callcc.thunk.org (pool-72-93-95-157.bstnma.fios.verizon.net [72.93.95.157]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 02JKJEjG024401 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 19 Mar 2020 16:19:14 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id 38C4F420EBA; Thu, 19 Mar 2020 16:19:14 -0400 (EDT) Date: Thu, 19 Mar 2020 16:19:14 -0400 From: "Theodore Y. Ts'o" To: Eric Biggers Subject: Re: [PATCH 1/4] fscrypt: add FS_IOC_GET_ENCRYPTION_NONCE ioctl Message-ID: <20200319201914.GD1067245@mit.edu> References: <20200314205052.93294-1-ebiggers@kernel.org> <20200314205052.93294-2-ebiggers@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200314205052.93294-2-ebiggers@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200319_131926_298927_06FC655A X-CRM114-Status: UNSURE ( 9.58 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-api@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-fscrypt@vger.kernel.org, linux-mtd@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Sat, Mar 14, 2020 at 01:50:49PM -0700, Eric Biggers wrote: > From: Eric Biggers > > Add an ioctl FS_IOC_GET_ENCRYPTION_NONCE which retrieves the nonce from > an encrypted file or directory. The nonce is the 16-byte random value > stored in the inode's encryption xattr. It is normally used together > with the master key to derive the inode's actual encryption key. > > The nonces are needed by automated tests that verify the correctness of > the ciphertext on-disk. Except for the IV_INO_LBLK_64 case, there's no > way to replicate a file's ciphertext without knowing that file's nonce. > > The nonces aren't secret, and the existing ciphertext verification tests > in xfstests retrieve them from disk using debugfs or dump.f2fs. But in > environments that lack these debugging tools, getting the nonces by > manually parsing the filesystem structure would be very hard. > > To make this important type of testing much easier, let's just add an > ioctl that retrieves the nonce. > > Signed-off-by: Eric Biggers Reviewed-by: Theodore Ts'o ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/