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Re: [TLS] Should we require implementations to send alerts?

Florian Weimer <fweimer@redhat.com> Tue, 15 September 2015 13:18 UTC

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To: Eric Rescorla <ekr@rtfm.com>, "tls@ietf.org" <tls@ietf.org>
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From: Florian Weimer <fweimer@redhat.com>
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Date: Tue, 15 Sep 2015 15:18:30 +0200
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Subject: Re: [TLS] Should we require implementations to send alerts?
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On 09/12/2015 10:49 PM, Eric Rescorla wrote:
> Issue: https://github.com/tlswg/tls13-spec/issues/242
> 
> In https://github.com/tlswg/tls13-spec/pull/231, Brian Smith argues:
> 
> "Nobody must ever be *required* to send an alert. Any requirement for
> sending an alert should be SHOULD, at most."

Using full-duplex TCP, it's difficult to get a fatal alert over the wire
if you want to close the connection immediately:

<http://www.ietf.org/mail-archive/web/tls/current/msg08342.html>

The workarounds proposed in that thread may not be always practical.

-- 
Florian Weimer / Red Hat Product Security

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