[TLS] Replacing HelloRetryRequest in TLS 1.3?
Dave Garrett <davemgarrett@gmail.com> Thu, 26 November 2015 23:03 UTC
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From: Dave Garrett <davemgarrett@gmail.com>
To: tls@ietf.org, Eric Rescorla <ekr@rtfm.com>
Date: Thu, 26 Nov 2015 18:03:30 -0500
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Subject: [TLS] Replacing HelloRetryRequest in TLS 1.3?
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HelloRetryRequest is annoying. Is there any way we can replace it with something? I know our options are limited, here. We can't mandate offers for everything, not just due to constrained environments, but also because post-quantum keys could get too big. The main thing that comes to mind would be to provide a way for a server to respond to a client with a ServerConfiguration, but not a hello, and put group support in there (maybe a whole supported_groups extension). Clients that don't provide the needed key would get a config and a fatal alert telling it that it needs to use a supported group from that config. The client could then retry as it does now or do 0-RTT with early data, which could cut an RTT out of the current flow. (This is similar to the QUIC way of doing things.) Dave
- [TLS] Replacing HelloRetryRequest in TLS 1.3? Dave Garrett
- Re: [TLS] Replacing HelloRetryRequest in TLS 1.3? Eric Rescorla