From owner-freebsd-current@freebsd.org Wed Aug 22 19:46:55 2018 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 351311093B92 for ; Wed, 22 Aug 2018 19:46:55 +0000 (UTC) (envelope-from sef@ixsystems.com) Received: from mail-pf1-x435.google.com (mail-pf1-x435.google.com [IPv6:2607:f8b0:4864:20::435]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id A6BBE880A6 for ; Wed, 22 Aug 2018 19:46:54 +0000 (UTC) (envelope-from sef@ixsystems.com) Received: by mail-pf1-x435.google.com with SMTP id i26-v6so1449675pfo.12 for ; Wed, 22 Aug 2018 12:46:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ixsystems-com.20150623.gappssmtp.com; s=20150623; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=NOv7n72cDyWUU7iJNV38AFpKId3+/WvjhxWV1Nrhajo=; b=Xbc+ow6mfHnVEE2ATrYMlU/GaFjnSxEAWHW9pHeKaFcGU6bpq3BaXtwIingm83bKpc bsLiQuI+npLzBU3DqFFDZ8Ae+Zb4joGMXP+zYUDhu9hsfacqZsmdh8lssc5siSx2ApMV yzNjfqElF2YbDKxTFQ/ihNbR7aJPaRcGk7QEBqNyrjVq9w3nv/+sZbJs28wK5aixu/FW Eb9kFUktBN7PxaClWKhgDIbyQxQa4EfXQMoPNsKKESZwDQ0KBFyTa8KlLq4BEVPTR7BF d1i531DhbBbkDsQKJVy+10SkwUs0O0ieEwf8rPOLEc+yr+6xaeY3j0rMYc75EKqBZa11 VKqg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=NOv7n72cDyWUU7iJNV38AFpKId3+/WvjhxWV1Nrhajo=; b=olXswX5Ac2gzFvUv1g422+2nWpPYDlcJ5a43M+IYHjRxxnxlqfPXmhnVeHPwmCBj8L 5PH3RZm9bIRO7eIEJawa7RNZLCMu7WwXEsD7mDZ3kEzwQKw3pxD2qy4E1cht+5e5CwS5 ITHTMO+LRjgDy5XtPi6fn9iZKHc0JP4vu729WLpp6oiTVRGRfsTdOg+q8B3QDreAygtq Oz6k2VhFZeGt1dquZwiJAF2VnMRVb6LNjsiZpKpOFgrAhctTRXa+47NyO72Z+iMPLl3l bDrT7vUXaEp4oiDhg03D1G7C+TRIs0oPnUULB9pOykqExxb49Frnz2Ro3RP1rqvreZIE D23w== X-Gm-Message-State: AOUpUlFAo0INcGAPE4OliYWKqaRCDJYpwHcut3QWf5klrT84+zc9LyuI exJQ6CUSAj3mhQp5ZwoVjWMXLgrr4fU= X-Google-Smtp-Source: AA+uWPy3k3gfkTlpp2P9WYn/Eo7SXxsZojUiXVcRVZM3PEQLFTzvZyVw5y0OFJGhkVe5p0FZp5pszg== X-Received: by 2002:a63:1760:: with SMTP id 32-v6mr22399958pgx.31.1534967213704; Wed, 22 Aug 2018 12:46:53 -0700 (PDT) Received: from [10.250.1.167] ([12.229.62.29]) by smtp.gmail.com with ESMTPSA id f11-v6sm3347916pfa.131.2018.08.22.12.46.52 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 22 Aug 2018 12:46:52 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 10.3 \(3273\)) Subject: Re: Native Encryption for ZFS on FreeBSD CFT From: Sean Fagan In-Reply-To: Date: Wed, 22 Aug 2018 12:46:51 -0700 Cc: Matthew Macy , FreeBSD CURRENT , freebsd-fs Content-Transfer-Encoding: quoted-printable Message-Id: <8C65E4ED-9AF3-4469-9C5A-BF058D50C3F5@ixsystems.com> References: <9FDF249A-E320-4652-834E-7EEC5C4FB7CA@ixsystems.com> To: Alan Somers X-Mailer: Apple Mail (2.3273) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 Aug 2018 19:46:55 -0000 On Aug 22, 2018, at 12:35 PM, Alan Somers wrote: > Only encrypting L0 blocks also leaks a lot of information. That means = that, if encryption is set to anything but "off", watermarking attacks = will still be possible based on the size and sparsity of a file. = Because I believe that with any encryption mode, ZFS turns continuous = runs of zeros into holes. And I don't see anything in zio_crypt.c that = addresses that. I=E2=80=99m not sure about that. However, with compression=3Doff, dd if=3D/dev/zero of=3Dbigfile bs=3D1m count=3D1024 results in a file that is 1565148 blocks (of 128k bytes), which supports = your statement. With compression=3Don, it creates a 1 block file. Sean.