Re: [TLS] Zero length fragments and fragmented Alert messages
Eric Rescorla <ekr@rtfm.com> Tue, 18 October 2016 10:56 UTC
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From: Eric Rescorla <ekr@rtfm.com>
Date: Tue, 18 Oct 2016 06:56:01 -0400
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To: Hubert Kario <hkario@redhat.com>
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Subject: Re: [TLS] Zero length fragments and fragmented Alert messages
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" decode_error A message could not be decoded because some field was
out of the specified range or the length of the message was
incorrect. "
I suppose you could argue that:
" This alert is used for errors where the message does
not conform to the formal protocol syntax. "
Rules that out, but I think I'm willing to stretch it here.
-Ekr
On Tue, Oct 18, 2016 at 6:28 AM, Hubert Kario <hkario@redhat.com> wrote:
> Current draft states:
>
> Alert messages ({{alert-protocol}}) MUST NOT be fragmented across
> records.
>
> and
>
> Implementations MUST NOT send zero-length fragments of Handshake or
> Alert types, even if those fragments contain padding.
>
> But I don't see what is the expected behaviour of the side receiving such
> malformed messages.
>
> Especially the fragmented alerts are unique in that any other message type
> can
> be fragmented, so no rules define how to handle incorrectly fragmented
> messages. Or at least I don't see them.
> --
> Regards,
> Hubert Kario
> Senior Quality Engineer, QE BaseOS Security team
> Web: www.cz.redhat.com
> Red Hat Czech s.r.o., Purkyňova 99/71, 612 45, Brno, Czech Republic
> _______________________________________________
> TLS mailing list
> TLS@ietf.org
> https://www.ietf.org/mailman/listinfo/tls
>
>
- [TLS] Zero length fragments and fragmented Alert … Hubert Kario
- Re: [TLS] Zero length fragments and fragmented Al… Eric Rescorla