Re: [TLS] Summarizing identity change discussion so far
"Blumenthal, Uri - 0662 - MITLL" <uri@ll.mit.edu> Fri, 18 December 2009 06:08 UTC
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From: "Blumenthal, Uri - 0662 - MITLL" <uri@ll.mit.edu>
To: "'david-sarah@jacaranda.org'" <david-sarah@jacaranda.org>, "'tls@ietf.org'" <tls@ietf.org>
Date: Fri, 18 Dec 2009 01:05:58 -0500
Thread-Topic: [TLS] Summarizing identity change discussion so far
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Subject: Re: [TLS] Summarizing identity change discussion so far
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My strong conviction is that the fact of non-zero probability to get (e.g.) PKIX identity matching wrong - does NOT invalidate the need for something more powerful and usable than memcmp. I'm not convinced that MD5 collision exploitation justifies restriction of matching to memcmp. Again, my strong conviction. ----- Original Message ----- From: tls-bounces@ietf.org <tls-bounces@ietf.org> To: tls@ietf.org <tls@ietf.org> Sent: Fri Dec 18 00:47:28 2009 Subject: Re: [TLS] Summarizing identity change discussion so far Kyle Hamilton wrote: > On Tue, Dec 8, 2009 at 1:13 AM, <Pasi.Eronen@nokia.com> wrote: >> (wearing Area Director hat) >> >> - We recommend that TLS libraries SHOULD provide identity matching >> (with memcmp, abort handshake if changed) functionality to >> applications, and SHOULD allow applications to enable/disable this >> functionality. > > No, identity matching SHOULD be done in accordance with PKIX. Strongly disagree. If implementations try to do identity matching that is any more complicated than memcmp then they *will* get it wrong; see <http://www.ioactive.com/pdfs/PKILayerCake.pdf> for evidence. -- David-Sarah Hopwood ⚥ http://davidsarah.livejournal.com
- [TLS] Summarizing identity change discussion so f… Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Blumenthal, Uri - 0662 - MITLL
- Re: [TLS] Summarizing identity change discussion … Stephen Farrell
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Eric Rescorla
- Re: [TLS] Summarizing identity change discussion … Marsh Ray
- Re: [TLS] Summarizing identity change discussion … Marsh Ray
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Stefan Santesson
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Michael Gray
- Re: [TLS] Summarizing identity change discussion … Marsh Ray
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Marsh Ray
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Kyle Hamilton
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Marsh Ray
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Michael Gray
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Michael Gray
- Re: [TLS] Summarizing identity change discussion … Marsh Ray
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Michael Gray
- Re: [TLS] Summarizing identity change discussion … Kyle Hamilton
- [TLS] OpenPGP Certs for TLS [was: Re: Summarizing… Daniel Kahn Gillmor
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Blumenthal, Uri - 0662 - MITLL
- Re: [TLS] Summarizing identity change discussion … Kyle Hamilton
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Kyle Hamilton
- Re: [TLS] Summarizing identity change discussion … Peter Saint-Andre
- Re: [TLS] Summarizing identity change discussion … Peter Saint-Andre
- Re: [TLS] Summarizing identity change discussion … Peter Saint-Andre
- Re: [TLS] Summarizing identity change discussion … Peter Saint-Andre
- Re: [TLS] Summarizing identity change discussion … David-Sarah Hopwood
- Re: [TLS] Summarizing identity change discussion … Blumenthal, Uri - 0662 - MITLL
- Re: [TLS] Summarizing identity change discussion … Marsh Ray
- Re: [TLS] Summarizing identity change discussion … Joseph Salowey (jsalowey)
- Re: [TLS] Summarizing identity change discussion … Stephen Farrell
- Re: [TLS] Summarizing identity change discussion … Martin Rex
- Re: [TLS] Summarizing identity change discussion … Nelson B Bolyard
- Re: [TLS] Summarizing identity change discussion … Nasko Oskov
- Re: [TLS] Summarizing identity change discussion … David-Sarah Hopwood
- Re: [TLS] Summarizing identity change discussion … David-Sarah Hopwood
- Re: [TLS] Summarizing identity change discussion … Joseph Salowey (jsalowey)
- Re: [TLS] Summarizing identity change discussion … Pasi.Eronen
- Re: [TLS] Summarizing identity change discussion … Joseph Salowey (jsalowey)