Re: [TLS] A closer look at ROBOT, BB Attacks, timing attacks in general, and what we can do in TLS
Hubert Kario <hkario@redhat.com> Wed, 03 January 2018 11:45 UTC
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From: Hubert Kario <hkario@redhat.com>
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Date: Wed, 03 Jan 2018 12:45:14 +0100
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Subject: Re: [TLS] A closer look at ROBOT, BB Attacks, timing attacks in general, and what we can do in TLS
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On Thursday, 14 December 2017 23:20:54 CET Colm MacCárthaigh wrote: > Based on our experiences with all of this over the last few weeks, I'd like > to summarize and throw out a few suggestions for making TLS stacks more > defensive and robust against problems of this class. One or two may be even > worth considering as small additions to the forthcoming TLS RFC, and I'd > love to get feedback on that. > > *Second: hide all alerts in suspicious error cases* > Next, when the handshake does fail, we do two non-standard things. The > first is that we don't return an alert message, we just close the > connection. > > *Third: mask timing side-channels with a massive delay* > The second non-standard thing we do is that in all error cases, s2n behaves > as if something suspicious is going on and in case timing is involved, we > add a random delay. It's well known that random delays are only partially > effective against timing attacks, but we add a very very big one. We wait a > random amount of time between a minimum of 10 seconds, and a maximum of 30 > seconds. Note that both of those things only _possibly_ frustrate attackers while they definitely frustrate researchers trying to characterise your implementation as vulnerable or not. In effect making it seem secure while in reality it may not be. -- Regards, Hubert Kario Senior Quality Engineer, QE BaseOS Security team Web: www.cz.redhat.com Red Hat Czech s.r.o., Purkyňova 115, 612 00 Brno, Czech Republic
- [TLS] A closer look at ROBOT, BB Attacks, timing … Colm MacCárthaigh
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Watson Ladd
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Colm MacCárthaigh
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Hanno Böck
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Colm MacCárthaigh
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Yoav Nir
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Nikos Mavrogiannopoulos
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Andrei Popov
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Kathleen Moriarty
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Hanno Böck
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Andrei Popov
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Eric Rescorla
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Watson Ladd
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Eric Rescorla
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Eric Rescorla
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Andrei Popov
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Tim Hollebeek
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Andrei Popov
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Tim Hollebeek
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Martin Rex
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Martin Rex
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Peter Gutmann
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Ilari Liusvaara
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Hubert Kario
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Hubert Kario
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Colm MacCárthaigh
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Hubert Kario
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Colm MacCárthaigh
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Hubert Kario
- Re: [TLS] A closer look at ROBOT, BB Attacks, tim… Colm MacCárthaigh