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Re: [TLS] SCSVs and SSLv3 fallback

Trevor Perrin <trevp@trevp.net> Fri, 05 April 2013 22:47 UTC

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Date: Fri, 05 Apr 2013 15:47:16 -0700
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From: Trevor Perrin <trevp@trevp.net>
To: Paul Hoffman <paul.hoffman@vpnc.org>
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Cc: tls@ietf.org
Subject: Re: [TLS] SCSVs and SSLv3 fallback
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On Fri, Apr 5, 2013 at 3:19 PM, Paul Hoffman <paul.hoffman@vpnc.org> wrote:
> On Apr 5, 2013, at 3:11 PM, Trevor Perrin <trevp@trevp.net> wrote:
>> On Fri, Apr 5, 2013 at 2:30 PM, Nikos Mavrogiannopoulos <nmav@gnutls.org> wrote:
>>>
>>> I wouldn't expect the problem of failed TLS connections due to middle
>>> boxes or bad implementations to disappear by making a complex protocol
>>> even more complex.
>>
>> If the problem is TLS-intolerant middleboxes, then allowing necessary
>> handshake data to flow via SSLv3, using a mechanism that has worked
>> for other extension data, should make the problem better.  No?
>
> No. You assume that the "TLS-intolerant middleboxes" actually understand real SSLv3, not some very limited and old picture of it. You might fix the problem for *some* middleboxes, at the cost of making the protocol even more fragile.

Well, we're agreed this might fix the problem for some middleboxes. :-)

The alternative, in the TLS-intolerant middlebox case, is... what,
exactly?  Fail to connect?


Trevor

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