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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B583EC63684 for ; Wed, 26 Jan 2022 14:51:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242362AbiAZOvx (ORCPT ); Wed, 26 Jan 2022 09:51:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35816 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242359AbiAZOvw (ORCPT ); Wed, 26 Jan 2022 09:51:52 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E330C06161C; Wed, 26 Jan 2022 06:51:52 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 09C7AB81E7D; Wed, 26 Jan 2022 14:51:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 18344C340E3; Wed, 26 Jan 2022 14:51:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643208709; bh=BfQsXByWn3JPY8Qa8YYeS8YTm9L6z6Xi8uDKWKMdcTs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=M5boXbX3q7PqM2UoCgFfeo2u+ew8eGGSDD9fxHU7SLeU3CWEDEWgwrdZGo02DuIp1 IE1ty/vEuN3NdeMhzEO/6QveRLK4h925gAo7fECGgf64JDSP8FPggspq7wwEJw2rPJ j4IyhPyZ3M1ksdu49nUVtyYgIRiCTovwaAfN0CHNGq5Xq0akMaHvIs0bpGXYJFeMdq 75tS+GWtlzZyYbyH4E/03QQeaYnfjydQ8LrygjE16//PRocrvgXkbG2Y+q2DnWWWuV +oYvXMHyprUaxYrYBpW4rPtuiw7V060p6YEIMdLaHVtYPkgurBTNv0cz4HRhRtNyS5 u83gh5E2PvZ0g== Date: Wed, 26 Jan 2022 16:51:29 +0200 From: Jarkko Sakkinen To: Martin Ross Cc: corbet@lwn.net, dhowells@redhat.com, jejb@linux.ibm.com, jmorris@namei.org, keyrings@vger.kernel.org, linux-doc@vger.kernel.org, linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, serge@hallyn.com, Yael Tiomkin , Mimi Zohar Subject: Re: [PATCH v4] KEYS: encrypted: Instantiate key with user-provided decrypted data Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Wed, Jan 26, 2022 at 04:47:22PM +0200, Jarkko Sakkinen wrote: > On Tue, Jan 18, 2022 at 01:26:05PM -0500, Martin Ross wrote: > > Hi Jarkko, > > > > I have been working with Yael on this project so I thought I might add > > a bit of background here around the use case that this series of > > patches is trying to address. > > > > At a high level we are trying to provide users of encryption that have > > key management hierarchies a better tradeoff between security and > > availability. For available and performance reasons master keys often > > need to be released (or derived/wrapped keys created) outside of a KMS > > to clients (which may in turn further wrap those keys in a series of > > levels). What we are trying to do is provide a mechanism where the > > wrapping/unwrapping of these keys is not dependent on a remote call at > > runtime. e.g. To unwrap a key if you are using AWS KMS or Google > > Service you need to make an RPC. In practice to defend against > > availability or performance issues, designers end up building their > > own kms and effectively encrypting everything with a DEK. The DEK > > encrypts same set as the master key thereby eliminating the security > > benefit of keeping the master key segregated in the first place. Mainly this part (would be enough to explain why it is there). BR, Jarkko