Re: [TLS] Question about unrecognized extension types in the TLS 1.3 client hello message
David Benjamin <davidben@chromium.org> Mon, 30 January 2017 21:56 UTC
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From: David Benjamin <davidben@chromium.org>
Date: Mon, 30 Jan 2017 21:55:51 +0000
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To: Adam Langley <agl@imperialviolet.org>, "Scott Fluhrer (sfluhrer)" <sfluhrer@cisco.com>
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Subject: Re: [TLS] Question about unrecognized extension types in the TLS 1.3 client hello message
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On Mon, Jan 30, 2017 at 4:45 PM Adam Langley <agl@imperialviolet.org> wrote: On Mon, Jan 30, 2017 at 1:41 PM, Scott Fluhrer (sfluhrer) <sfluhrer@cisco.com> wrote: > My question: in TLS 1.3, if the client inserts an extension of a type that > the server does not recognize, how must the server behave? Is it required > that the server just ignore the extension, or can it take some other action > (e.g. ignore the client hello)? The server must ignore unknown extensions. Here's a PR to spell this out more explicitly in the text: https://github.com/tlswg/tls13-spec/pull/868 I could have sworn this was in there already, but apparently not? That or I can't read. David
- [TLS] Question about unrecognized extension types… Scott Fluhrer (sfluhrer)
- Re: [TLS] Question about unrecognized extension t… Adam Langley
- Re: [TLS] Question about unrecognized extension t… David Benjamin