Re: [TLS] Encryption of TLS 1.3 content type

Peter Gutmann <pgut001@cs.auckland.ac.nz> Tue, 29 July 2014 12:51 UTC

From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "<tls@ietf.org>" <tls@ietf.org>
Thread-Topic: [TLS] Encryption of TLS 1.3 content type
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Date: Tue, 29 Jul 2014 12:51:19 +0000
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Subject: Re: [TLS] Encryption of TLS 1.3 content type
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Viktor Dukhovni <ietf-dane@dukhovni.org> writes:

>Yes, some application application protocols do send short messages, for
>example SMTP an server may reply "250 2.0.0 OK\r\n".  However, (fatal) alerts
>often terminate the connection and are easily distinguished from routine
>traffic.
>
>In chatty protocols, like SMTP, TLS masks the specific content, but not the
>overall flow or size of messages.  One can often tell which application data
>messages carry "EHLO", "MAIL", "RCPT", "DATA" and the message payload,
>despite the use of TLS.  The attacker does not learn very much, but may be
>able to estimate the recipient count, even with ESMTP PIPELINING and of
>course can estimate the message size fairly well.

+1 (saves me typing up the same thing :-).

Peter.

[TLS] Encryption of TLS 1.3 content type Joseph Salowey (jsalowey)
Re: [TLS] Encryption of TLS 1.3 content type Yoav Nir
Re: [TLS] Encryption of TLS 1.3 content type Fabrice Gautier
Re: [TLS] Encryption of TLS 1.3 content type Eric Rescorla
Re: [TLS] Encryption of TLS 1.3 content type Watson Ladd
Re: [TLS] Encryption of TLS 1.3 content type Colm MacCárthaigh
Re: [TLS] Encryption of TLS 1.3 content type Peter Gutmann
Re: [TLS] Encryption of TLS 1.3 content type Yoav Nir
Re: [TLS] Encryption of TLS 1.3 content type Nikos Mavrogiannopoulos
Re: [TLS] Encryption of TLS 1.3 content type Yoav Nir
Re: [TLS] Encryption of TLS 1.3 content type Daniel Kahn Gillmor
Re: [TLS] Encryption of TLS 1.3 content type Martin Rex
Re: [TLS] Encryption of TLS 1.3 content type Colm MacCárthaigh
Re: [TLS] Encryption of TLS 1.3 content type Nikos Mavrogiannopoulos
Re: [TLS] Encryption of TLS 1.3 content type Daniel Kahn Gillmor
Re: [TLS] Encryption of TLS 1.3 content type Nikos Mavrogiannopoulos
Re: [TLS] Encryption of TLS 1.3 content type Viktor Dukhovni
Re: [TLS] Encryption of TLS 1.3 content type Brian Sniffen
Re: [TLS] Encryption of TLS 1.3 content type Stephen Farrell
Re: [TLS] Encryption of TLS 1.3 content type Michael StJohns
Re: [TLS] Encryption of TLS 1.3 content type Yoav Nir
Re: [TLS] Encryption of TLS 1.3 content type Colm MacCárthaigh
Re: [TLS] Encryption of TLS 1.3 content type Juho Vähä-Herttua
Re: [TLS] Encryption of TLS 1.3 content type Eric Rescorla
Re: [TLS] Encryption of TLS 1.3 content type Andy Lutomirski
Re: [TLS] Encryption of TLS 1.3 content type Peter Gutmann
Re: [TLS] Encryption of TLS 1.3 content type Alfredo Pironti
Re: [TLS] Encryption of TLS 1.3 content type Martin Rex
Re: [TLS] Encryption of TLS 1.3 content type Alfredo Pironti