Re: [TLS] TLS 1.3 - Support for compression to be removed
Stephen Farrell <stephen.farrell@cs.tcd.ie> Tue, 22 September 2015 19:29 UTC
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To: Yoav Nir <ynir.ietf@gmail.com>
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From: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Cc: "tls@ietf.org" <tls@ietf.org>, Simon Josefsson <simon@josefsson.org>
Subject: Re: [TLS] TLS 1.3 - Support for compression to be removed
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On 22/09/15 19:32, Yoav Nir wrote: > >> On Sep 22, 2015, at 8:35 PM, Stephen Farrell <stephen.farrell@cs.tcd.ie> wrote: >> >> >> >> On 22/09/15 17:23, Tony Arcieri wrote: >>> But an unsafe feature shouldn't be kept in >>> TLS just because some protocols want to do unsafe things and are too lazy >>> to implement their own compression. >> >> Compression does have issues clearly, but it's not correct to describe >> people wanting TLS to compress as lazy. They're rather looking for the >> same features that TLS has offered for a couple of decades. So if there >> were a way to help them, that'd be good. And if not, the onus I think >> is on us in this WG to clearly explain why we're removing that feature >> in TLS1.3. >> >> That doesn't have to be text in the TLS1.3 specification but I would >> guess the question may keep coming up, so documenting the answer in >> some archival form (such as an RFC:-) might be a good plan. > > Doesn’t this count? It does count, but doesn't cover TLS1.3. And it's when TLS1.3 hits the shelves that we'll maybe get more and more folks waking up to the fact that we've removed functionality. (That's not so different to what seems to be happening with HTTP/2 and client-auth maybe.) But yes, text along those lines is what'd be needed. Depending on the overall scope, one might want more self-contained text and less of a dependency on references, not sure. S. > > 3.3. Compression > > > In order to help prevent compression-related attacks (summarized in > Section 2.6 of [RFC7457]), implementations and deployments SHOULD > disable TLS-level compression (Section 6.2.2 of [RFC5246]), unless > the application protocol in question has been shown not to be open to > such attacks. > > Rationale: TLS compression has been subject to security attacks, such > as the CRIME attack. > > (From RFC 7525) > > Sure, we could leave compression in the spec, and recommend that HTTP MUST NOT use it while NNTP MAY. > > A protocol for multiple use-cases can be either one size fits all, or else have a bunch of knobs for the different uses. I prefer the one size fits all approach. > > More specific to compression: people had been using TLS (and SSL) to encrypt HTTP for over two decades before the CRIME attack. That’s how long it took to realize that it is dangerous for HTTP. Are people that sure that a similar issue doesn’t exist for the much less analyzed NNTP? > > Yoav >
- [TLS] TLS 1.3 - Support for compression to be rem… Alewa, Christos
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Salz, Rich
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Kurt Roeckx
- Re: [TLS] TLS 1.3 - Support for compression to be… Loganaden Velvindron
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Geoffrey Keating
- Re: [TLS] TLS 1.3 - Support for compression to be… Salz, Rich
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Watson Ladd
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Karthikeyan Bhargavan
- Re: [TLS] TLS 1.3 - Support for compression to be… Salz, Rich
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Viktor Dukhovni
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Daniel Kahn Gillmor
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Thijs van Dijk
- Re: [TLS] TLS 1.3 - Support for compression to be… Simon Josefsson
- Re: [TLS] TLS 1.3 - Support for compression to be… Blumenthal, Uri - 0553 - MITLL
- Re: [TLS] TLS 1.3 - Support for compression to be… Watson Ladd
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Stephen Farrell
- Re: [TLS] TLS 1.3 - Support for compression to be… Joseph Lorenzo Hall
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Yoav Nir
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Salz, Rich
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Watson Ladd
- Re: [TLS] TLS 1.3 - Support for compression to be… Stephen Farrell
- Re: [TLS] TLS 1.3 - Support for compression to be… Yoav Nir
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Benjamin Kaduk
- Re: [TLS] TLS 1.3 - Support for compression to be… Kurt Roeckx
- Re: [TLS] TLS 1.3 - Support for compression to be… Peter Gutmann
- Re: [TLS] TLS 1.3 - Support for compression to be… Colm MacCárthaigh
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Colm MacCárthaigh
- Re: [TLS] TLS 1.3 - Support for compression to be… Bill Frantz
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Björn Tackmann
- Re: [TLS] TLS 1.3 - Support for compression to be… Bill Frantz
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Yoav Nir
- Re: [TLS] TLS 1.3 - Support for compression to be… Nikos Mavrogiannopoulos
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeremy Harris
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Viktor Dukhovni
- Re: [TLS] TLS 1.3 - Support for compression to be… Yuhong Bao
- Re: [TLS] TLS 1.3 - Support for compression to be… Salz, Rich
- Re: [TLS] TLS 1.3 - Support for compression to be… Viktor Dukhovni
- Re: [TLS] TLS 1.3 - Support for compression to be… takamichi saito
- Re: [TLS] TLS 1.3 - Support for compression to be… Roland Zink
- Re: [TLS] TLS 1.3 - Support for compression to be… Salz, Rich
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Daniel Kahn Gillmor
- Re: [TLS] TLS 1.3 - Support for compression to be… Salz, Rich
- Re: [TLS] TLS 1.3 - Support for compression to be… Martin Rex
- Re: [TLS] TLS 1.3 - Support for compression to be… Yoav Nir
- Re: [TLS] TLS 1.3 - Support for compression to be… Daniel Kahn Gillmor
- Re: [TLS] TLS 1.3 - Support for compression to be… Ilari Liusvaara
- Re: [TLS] TLS 1.3 - Support for compression to be… takamichi saito
- Re: [TLS] TLS 1.3 - Support for compression to be… takamichi saito
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Yoav Nir
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Watson Ladd
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Salz, Rich
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Martin Thomson
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Martin Thomson
- Re: [TLS] TLS 1.3 - Support for compression to be… Douglas Stebila
- Re: [TLS] TLS 1.3 - Support for compression to be… Martin Rex
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Martin Rex
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Short, Todd
- Re: [TLS] TLS 1.3 - Support for compression to be… Geoffrey Keating
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Bill Frantz
- Re: [TLS] TLS 1.3 - Support for compression to be… Martin Rex
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Watson Ladd
- Re: [TLS] TLS 1.3 - Support for compression to be… Jeffrey Walton
- Re: [TLS] TLS 1.3 - Support for compression to be… Tony Arcieri
- Re: [TLS] TLS 1.3 - Support for compression to be… Short, Todd
- Re: [TLS] TLS 1.3 - Support for compression to be… Eric Rescorla
- Re: [TLS] TLS 1.3 - Support for compression to be… Joseph Salowey
- Re: [TLS] TLS 1.3 - Support for compression to be… Martin Rex
- Re: [TLS] TLS 1.3 - Support for compression to be… Watson Ladd
- Re: [TLS] TLS 1.3 - Support for compression to be… Martin Rex
- Re: [TLS] TLS 1.3 - Support for compression to be… Dave Garrett
- Re: [TLS] TLS 1.3 - Support for compression to be… takamichi saito
- Re: [TLS] TLS 1.3 - Support for compression to be… takamichi saito
- Re: [TLS] TLS 1.3 - Support for compression to be… Julien ÉLIE