Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fast-Track" draft posted

Nikos Mavrogiannopoulos <nmav@gnutls.org> Tue, 02 February 2010 16:18 UTC

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Date: Tue, 02 Feb 2010 17:18:50 +0100
From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
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Cc: tls@ietf.org
Subject: Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fast-Track" draft posted
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Adam Langley wrote:

> The length of the application data records are observable on the wire
> in any case. The only advantage that an attacker could gain here is to
> choose a cipher that doesn't pad records to get a slighter more
> accurate length.

TLS uses random padding in block cipher thus length is typically not
observable unless of course if random padding is not used.

regards,
Nikos