Re: [TLS] PR#625: Change alert requirements

Eric Rescorla <ekr@rtfm.com> Wed, 07 September 2016 17:19 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Wed, 7 Sep 2016 10:19:02 -0700
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To: Hubert Kario <hkario@redhat.com>
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Subject: Re: [TLS] PR#625: Change alert requirements
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On Wed, Sep 7, 2016 at 10:05 AM, Hubert Kario <hkario@redhat.com>; wrote:

> On Monday, 5 September 2016 11:02:57 CEST Eric Rescorla wrote:
> > PR: https://github.com/tlswg/tls13-spec/pull/625
> >
> > Currently the TLS spec requires implementations to send alerts under
> various
> > fatal conditions. However, many stacks actually don't send alerts
>
> the only popular stack I found that does not seem to send alerts is the
> schannel from Microsoft
>

Well, that's a fairly popular stack.



> F5, FortiOS, OpenSSL, NSS, GnuTLS, Java, mbedTLS, botan, axtls, Go
> implementation of TLS, all send alert messages
>

My understanding is that this is situation-dependent and that some systems
do not send alerts all the time.


> Note that these are to some extent orthogonal changes; even if we decide
> to
> > continue mandating sending alerts, that should be listed in one location
> not
> > scattered around the spec.
>
> In my opinion, putting the information how to handle errors in processing
> given message near the definition of a message makes it easier for
> implementers to implement and makes it less likely that they'll miss error
> handling.
>

Fair enough. I think this is a question of editor discretion.

-Ekr


> --
> Regards,
> Hubert Kario
> Senior Quality Engineer, QE BaseOS Security team
> Web: www.cz.redhat.com
> Red Hat Czech s.r.o., Purky┼łova 99/71, 612 45, Brno, Czech Republic