Re: [DNSOP] Whiskey Tango Foxtrot on key lengths...
Stephane Bortzmeyer <bortzmeyer@nic.fr> Wed, 02 April 2014 13:48 UTC
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Date: Wed, 02 Apr 2014 15:47:24 +0200
From: Stephane Bortzmeyer <bortzmeyer@nic.fr>
To: Olafur Gudmundsson <ogud@ogud.com>
Message-ID: <20140402134724.GA12506@nic.fr>
References: <0EA28BE8-E872-46BA-85FD-7333A1E13172@icsi.berkeley.edu> <53345C77.8040603@uni-due.de> <B7893984-2FAD-472D-9A4E-766A5C212132@pch.net> <102C13BE-E45E-437A-A592-FA373FF5C8F0@ogud.com> <474B0834-C16B-4843-AA0A-FC2A2085FEFB@icsi.berkeley.edu> <CFA0ED6F-6800-4638-90B0-CD414301C501@ogud.com>
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Subject: Re: [DNSOP] Whiskey Tango Foxtrot on key lengths...
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On Tue, Apr 01, 2014 at 10:37:54PM -0400, Olafur Gudmundsson <ogud@ogud.com> wrote a message of 158 lines which said: > Furthermore using larger keys than your parents is non-sensical as > that moves the cheap point of key cracking attack. Mostly true, but still too strong a statement, in my opinion. This is because, if you are an attacker and managed to crack a key somewhere between the root (inclusive) and your real target, the higher you are in the tree, the more things you have to emulate or simulate below. If you are after ogud.com, and you cracked the root key, you need to either create a false DS for .com (and then the resolver will croak on most .com responses, detecting there is something wrong) or a false NSEC proving that .com is not signed (but the fact that .com is signed is rapidly cached in validating resolvers). So, yes, basically, you are right, since DNSSEC is tree-based, the security of the weakest node is what matters. But, in practice, exploiting a cracked key upper in the tree is a bit more difficult than it seems.
- [DNSOP] Whiskey Tango Foxtrot on key lengths... Nicholas Weaver
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Nicholas Weaver
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Joe Abley
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Paul Hoffman
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Nicholas Weaver
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Rose, Scott
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Stephane Bortzmeyer
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Matthäus Wander
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Christopher Morrow
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Nicholas Weaver
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Christopher Morrow
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Paul Wouters
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Paul Wouters
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Joe Abley
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Joe Abley
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Bill Woodcock
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Tony Finch
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Colm MacCárthaigh
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Andrew Sullivan
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Tony Finch
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Joe Abley
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Thierry Moreau
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Matthäus Wander
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Joe Abley
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Colm MacCárthaigh
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… S Moonesamy
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Olafur Gudmundsson
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Bill Woodcock
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Nicholas Weaver
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Nicholas Weaver
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Jelte Jansen
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Mark Andrews
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Colm MacCárthaigh
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Mark Andrews
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Colm MacCárthaigh
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Olafur Gudmundsson
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Olafur Gudmundsson
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Paul Hoffman
- [DNSOP] CD (Re: Whiskey Tango Foxtrot on key leng… Evan Hunt
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Mark Andrews
- [DNSOP] CD bit (was Re: Whiskey Tango Foxtrot on … Andrew Sullivan
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Olafur Gudmundsson
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Colm MacCárthaigh
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Paul Wouters
- Re: [DNSOP] CD bit (was Re: Whiskey Tango Foxtrot… Mark Andrews
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Nicholas Weaver
- Re: [DNSOP] CD bit (was Re: Whiskey Tango Foxtrot… Andrew Sullivan
- Re: [DNSOP] CD (Re: Whiskey Tango Foxtrot on key … Colm MacCárthaigh
- Re: [DNSOP] CD (Re: Whiskey Tango Foxtrot on key … Nicholas Weaver
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Phillip Hallam-Baker
- [DNSOP] Current DNSOP thread and why 1024 bits Edward Lewis
- Re: [DNSOP] Current DNSOP thread and why 1024 bits Nicholas Weaver
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Stephane Bortzmeyer
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Paul Hoffman
- Re: [DNSOP] Current DNSOP thread and why 1024 bits Paul Hoffman
- [DNSOP] mailing list behavior Re: Current DNSOP t… Suzanne Woolf
- Re: [DNSOP] Current DNSOP thread and why 1024 bits Colm MacCárthaigh
- Re: [DNSOP] Current DNSOP thread and why 1024 bits Paul Wouters
- Re: [DNSOP] Current DNSOP thread and why 1024 bits S Moonesamy
- Re: [DNSOP] Current DNSOP thread and why 1024 bits Paul Hoffman
- Re: [DNSOP] Current DNSOP thread and why 1024 bits Rose, Scott
- Re: [DNSOP] CD (Re: Whiskey Tango Foxtrot on key … Mark Andrews
- Re: [DNSOP] CD (Re: Whiskey Tango Foxtrot on key … Colm MacCárthaigh
- Re: [DNSOP] Current DNSOP thread and why 1024 bits S Moonesamy
- Re: [DNSOP] Current DNSOP thread and why 1024 bits David Conrad
- Re: [DNSOP] Current DNSOP thread and why 1024 bits Paul Wouters
- Re: [DNSOP] Current DNSOP thread and why 1024 bits Ben Laurie
- Re: [DNSOP] Whiskey Tango Foxtrot on key lengths.… Francis Dupont