Re: [TLS] Possible blocking of Encrypted SNI extension in China
Rob Sayre <sayrer@gmail.com> Tue, 11 August 2020 05:42 UTC
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From: Rob Sayre <sayrer@gmail.com>
Date: Mon, 10 Aug 2020 22:41:50 -0700
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To: Peter Gutmann <pgut001@cs.auckland.ac.nz>
Cc: Christian Huitema <huitema@huitema.net>,
Christopher Wood <caw@heapingbits.net>, "TLS@ietf.org" <tls@ietf.org>
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Subject: Re: [TLS] Possible blocking of Encrypted SNI extension in China
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On Mon, Aug 10, 2020 at 10:33 PM Peter Gutmann <pgut001@cs.auckland.ac.nz> wrote: > Christian Huitema <huitema@huitema.net> writes: > > >Fingerprinting is a real issue but from the reports, this is not what is > >happening here. > > Sure, I was just pointing out that they're using the brute-force approach > now > but presumably at some point will stop blocking when they've implemented a > way > to bypass it. My guess is that since the GFW uses blocklisting (of known > sites/pages) all they'll need to do is fingerprint the sites they want to > block and take it from there. > Do you think this fingerprinting will work with the newer ECH design, if the client can add arbitrary content to the encrypted payload? Another technique to use here: deploy servers that refuse unencrypted ClientHello messages. thanks, Rob
- [TLS] Possible blocking of Encrypted SNI extensio… onoketa
- Re: [TLS] Possible blocking of Encrypted SNI exte… Christian Huitema
- Re: [TLS] Possible blocking of Encrypted SNI exte… David Fifield
- Re: [TLS] Possible blocking of Encrypted SNI exte… David Fifield
- Re: [TLS] Possible blocking of Encrypted SNI exte… Blumenthal, Uri - 0553 - MITLL
- Re: [TLS] Possible blocking of Encrypted SNI exte… Dmitry Belyavsky
- Re: [TLS] Possible blocking of Encrypted SNI exte… Peter Gutmann
- Re: [TLS] Possible blocking of Encrypted SNI exte… Christian Huitema
- Re: [TLS] Possible blocking of Encrypted SNI exte… Christopher Wood
- Re: [TLS] Possible blocking of Encrypted SNI exte… David Fifield
- Re: [TLS] Possible blocking of Encrypted SNI exte… Salz, Rich
- Re: [TLS] Possible blocking of Encrypted SNI exte… Peter Gutmann
- Re: [TLS] Possible blocking of Encrypted SNI exte… Christian Huitema
- Re: [TLS] Possible blocking of Encrypted SNI exte… Peter Gutmann
- Re: [TLS] Possible blocking of Encrypted SNI exte… Rob Sayre
- Re: [TLS] Possible blocking of Encrypted SNI exte… Peter Gutmann
- Re: [TLS] Possible blocking of Encrypted SNI exte… Rob Sayre
- Re: [TLS] Possible blocking of Encrypted SNI exte… Christian Huitema
- Re: [TLS] Possible blocking of Encrypted SNI exte… Rob Sayre
- Re: [TLS] Possible blocking of Encrypted SNI exte… Christian Huitema
- Re: [TLS] Possible blocking of Encrypted SNI exte… Peter Gutmann
- Re: [TLS] Possible blocking of Encrypted SNI exte… Rob Sayre
- Re: [TLS] Possible blocking of Encrypted SNI exte… David Fifield
- Re: [TLS] Possible blocking of Encrypted SNI exte… Nick Sullivan
- Re: [TLS] Possible blocking of Encrypted SNI exte… David Fifield
- Re: [TLS] Possible blocking of Encrypted SNI exte… Rob Sayre
- Re: [TLS] Possible blocking of Encrypted SNI exte… Peter Gutmann
- Re: [TLS] Possible blocking of Encrypted SNI exte… Rob Sayre
- Re: [TLS] Possible blocking of Encrypted SNI exte… Peter Gutmann
- Re: [TLS] Possible blocking of Encrypted SNI exte… Rob Sayre
- Re: [TLS] Possible blocking of Encrypted SNI exte… David Fifield
- Re: [TLS] Possible blocking of Encrypted SNI exte… David Fifield
- Re: [TLS] Possible blocking of Encrypted SNI exte… Carrick Bartle
- Re: [TLS] Possible blocking of Encrypted SNI exte… David Fifield