Re: [rtcweb] [TLS] Short Authentication String for TLS/DTLS Draft
Adam Langley <agl@google.com> Fri, 14 February 2014 23:41 UTC
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From: Adam Langley <agl@google.com>
Date: Fri, 14 Feb 2014 18:41:18 -0500
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To: Eric Rescorla <ekr@rtfm.com>
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Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>, "tls@ietf.org" <tls@ietf.org>
Subject: Re: [rtcweb] [TLS] Short Authentication String for TLS/DTLS Draft
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On Fri, Feb 14, 2014 at 6:28 PM, Eric Rescorla <ekr@rtfm.com> wrote: > RTCWEB WG members may be interested in the following draft: > > http://tools.ietf.org/html/draft-miers-tls-sas-00 > > This draft specifies a Short Authentication String feature for > TLS and DTLS which would allow a pair of communicating > to compare SAS values computed from the TLS/DTLS > handshake in order to detect active attack. I think the draft should discuss why a channel binding doesn't work. It's hinted at in the introduction but it's a subtle point because they are otherwise very similar. Given that I see M. Green as an author, should I assume that the requirement for 64 bytes of randomness for a /short/ authentication string is to ensure that users of Dual_EC DRBG have no problems leaking the necessary entropy to a passive observer? :) Cheers AGL
- [rtcweb] Short Authentication String for TLS/DTLS… Eric Rescorla
- Re: [rtcweb] [TLS] Short Authentication String fo… Adam Langley