Re: [TLS] WGLC for draft-ietf-tls-ticketrequests
Viktor Dukhovni <ietf-dane@dukhovni.org> Tue, 21 January 2020 09:16 UTC
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From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [TLS] WGLC for draft-ietf-tls-ticketrequests
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On Tue, Jan 21, 2020 at 07:57:27PM +1100, Martin Thomson wrote: > On Tue, Jan 21, 2020, at 16:54, Viktor Dukhovni wrote: > > There's no need to exclude valid use-cases. The refined proposal > > is rather non-invasive, and handles this case cost-effectively > > on clients that re-use tickets (and don't use early-data, ...). > > I don't find your arguments persuasive. This adds complexity > specifically to address a case that has - in the general case - > suboptimal characteristics, both in terms of forward secrecy and > linkability. Whether or not there are specific cases that might > tolerate these suboptimalities, the complexity and risks are borne by > everyone. * Switching to a new ticket is of no help if the server is still using the same STEK. Any forward-secrecy concerns are a function of the frequency of STEK rotation on the server. * We work in noticeably different application spaces. SMTP client MTAs send 220 greetings and EHLO commands identifying themselves in the clear prior to the STARTTLS handshake. MTAs don't roam from network to network, and linkability of traffic is not a concern. * Postfix, for example, rotates STEKs by default once an hour, making the forward-secrecy exposure quite limited. * Clients don't use the same ticket indefinitely, they too discard stale tickets, if the server does not beat them to it. The requested change is rather minimal, it merely asks the server to intepret 0 as "optional ticket" rather than "no ticket" reserving the last code point (not uncommon to have make it special) as a no-go sentinel. Even if the proposal is not compelling for some, it allows additional legitimate use-cases at negligible cost. So barring some actual problem, it is hard to see on what basis it can be reasonably excluded. That's all from me. Thanks. -- Viktor.
- [TLS] WGLC for draft-ietf-tls-ticketrequests Sean Turner
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Salz, Rich
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Martin Thomson
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Christopher Wood
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Christopher Wood
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Christopher Wood
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Christopher Wood
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Christopher Wood
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Hubert Kario
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Christopher Wood
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Hubert Kario
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Hubert Kario
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Benjamin Kaduk
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Jeremy Harris
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Benjamin Kaduk
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests David Schinazi
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Christopher Wood
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Martin Thomson
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests David Schinazi
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests David Schinazi
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Benjamin Kaduk
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Benjamin Kaduk
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Sean Turner
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Hubert Kario
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Martin Thomson
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Martin Thomson
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Eric Rescorla
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Salz, Rich
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Salz, Rich
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Eric Rescorla
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Watson Ladd
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Hubert Kario
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Watson Ladd
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Salz, Rich
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Stephen Farrell
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Salz, Rich
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Salz, Rich
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Salz, Rich
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Watson Ladd
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Watson Ladd
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Eric Rescorla
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Eric Rescorla
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Eric Rescorla
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Nico Williams
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Bill Frantz
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Eric Rescorla
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Tommy Pauly
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Eric Rescorla
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Ben Schwartz
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Ben Schwartz
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Daniel Migault
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Rob Sayre
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Hubert Kario
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Jeremy Harris
- Re: [TLS] WGLC for draft-ietf-tls-ticketrequests Viktor Dukhovni