Re: [TLS] SNI as authorization token?
Rob Sayre <sayrer@gmail.com> Tue, 04 May 2021 23:30 UTC
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From: Rob Sayre <sayrer@gmail.com>
Date: Tue, 04 May 2021 16:30:08 -0700
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To: Benjamin Kaduk <bkaduk=40akamai.com@dmarc.ietf.org>
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Subject: Re: [TLS] SNI as authorization token?
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On Tue, May 4, 2021 at 4:20 PM Benjamin Kaduk <bkaduk= 40akamai.com@dmarc.ietf.org> wrote: > Hi all, > > I'm reviewing draft-ietf-dprive-xfr-over-tls for this week's IESG > telechat, and > in > https://datatracker.ietf.org/doc/html/draft-ietf-dprive-xfr-over-tls-11#appendix-A.3 > it seems to suggest that a TLS server might only choose to allow > connections that > include a specific (secret-ish) SNI value. Given that the "as above" > listed "con" > seems to indicate that there are no relevant implementations of this > functionality, > I plan to push back on its inclusion in the document; a PSK mode (with > cert, > per RFC 8773) would seem to be universally superior. > > Am I correct to do so? Do we know of any cases where the SNI value is > being > (ab)used as an authorization token in this manner? > It certainly happens with subdomains. I'd recommend removing that entire appendix, though. It seems like generic TLS / DoS advice that doesn't really belong in the document. thanks, Rob
- [TLS] SNI as authorization token? Benjamin Kaduk
- Re: [TLS] SNI as authorization token? Rob Sayre
- Re: [TLS] SNI as authorization token? Martin Thomson
- Re: [TLS] SNI as authorization token? Benjamin Kaduk
- Re: [TLS] SNI as authorization token? Salz, Rich