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Re: [TLS] MUST <x> or what?

Peter Gutmann <pgut001@cs.auckland.ac.nz> Fri, 28 August 2015 04:24 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Martin Thomson <martin.thomson@gmail.com>, Dave Garrett <davemgarrett@gmail.com>
Thread-Topic: [TLS] MUST <x> or what?
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Date: Fri, 28 Aug 2015 04:24:36 +0000
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Subject: Re: [TLS] MUST <x> or what?
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Martin Thomson <martin.thomson@gmail.com> writes:

>An endpoint that receives an illegal combination of "things" MAY choose to 
>treat that as a fatal error.

Does that actually help?  What it's saying in full is:

  An endpoint that receives an illegal combination of "things" MAY choose to 
  treat that as a fatal error or MAY choose not to treat it as a fatal error.

which is a no-op.  Admittedly it explicitly allows you to treat it as an error 
while previously the response was left open, but it's still not terribly 
useful, anyone writing a client that submits gibberish things can claim it's 
OK and the server needs to be fixed to accept it.

Peter.

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