linux-kernel - Re: [PATCH 0/4][RFC v2] Introduce the in-kernel hibernation encryption

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20180809065306.GA24201@amd>
Date:   Thu, 9 Aug 2018 08:53:06 +0200
From:   Pavel Machek <pavel@....cz>
To:     Yu Chen <yu.c.chen@...el.com>
Cc:     Ryan Chen <yu.chen.surf@...il.com>, jlee@...e.com,
        oneukum@...e.com, "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
        ebiggers@...gle.com, Theodore Ts'o <tytso@....edu>,
        smueller@...onox.de, denkenz@...il.com,
        Linux PM list <linux-pm@...r.kernel.org>,
        linux-crypto@...r.kernel.org,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        kookoo.gu@...el.com, Zhang Rui <rui.zhang@...el.com>
Subject: Re: [PATCH 0/4][RFC v2] Introduce the in-kernel hibernation
 encryption

Hi!

> > Define unsafe.
> > 
> > If you want security against bad people resuming your machines, please
> Yes, this is one of the requirements.

> > But I thought you were trying to do something for secure boot, and "bad
> > person resumes your machine" is out of scope there.
> > 
> Not exactly, secure boot is one solution to meet the requirement.

Is it? AFAICT secure boot is something else. "Not even owner can see
kernel memory".

> > So please always explain security against _what kind of attack_ you
> > are trying to improve; intelligent communication is not possible
> > without that.
> > 
> User requirement:
> A is the user, B is the attacker, user A launches a STD and
> encrypts A's ram data, then writes these encrypted data onto
> the disk,  so that: Even if user B has access to the disk,
> B could not know the content of A. Which implies:
> 1. If B unplugs the disk from A's machine, and plugs the disk onto
>    another machine, B could not decode the content without A's
>    'permission'.
> 2. If B is using the same machine as A, even A has walked away leaving
>    the system suspend, B could not resume to A's context without
>    A's 'permission'.

Ok. Let's call this "effective resume password".

> Previously, there are three proposal for this:
> a. Enhance the uswsusp(Pavel)

Actually you don't have to enhance anything. Uswsusp already provides
"effective resume password".

If you only want to ask for password on resume, RSA is needed.

> Then let's talk a little more about secure boot. According
> to my understanding, the situation secure boot tries to deal
> with is a little different from the user case we raised above -
> It is an enhancement for case 1, because it refuses to resume
> once the machine is changed. And it does not cover case 2. But
> if it is a requirement from the user, that's ok.

That does not match my understanding of secure boot.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Download attachment "signature.asc" of type "application/pgp-signature" (182 bytes)