[TLS] Still more on Record Layers

JCA <1.41421@gmail.com> Mon, 02 August 2010 15:36 UTC

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Date: Mon, 02 Aug 2010 09:37:20 -0600
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From: JCA <1.41421@gmail.com>
To: tls@ietf.org
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Subject: [TLS] Still more on Record Layers
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   I am somewhat confused about the meaning of the length field in a
Record Layer. I believe that when the protocol messages, MAC and
padding (if any) are encrypted in a Record Layer, the length field
contains the length in bytes of this encrypted blob (otherwise I guess
it would be difficult to determine when a Record Layer being received
ends.) Now it would seem that with the exception of the
TLS_NULL_WITH_NULL_NULL cipher suite (which seems to be equivalent to
what happens during the initial handshake, where no cryptographic
cipher suite has been agreed on yet) if you have encryption you
necessarily have MAC, but you can have MAC without encryption. What
does the Record Layer length field contain in the latter case? Is it
the length of the (unencrypted) encapsulated protocol messages alone,
or the sum of this plus the length of the MAC?

[TLS] Still more on Record Layers JCA
Re: [TLS] Still more on Record Layers Brian Smith
Re: [TLS] Still more on Record Layers Marsh Ray
Re: [TLS] Still more on Record Layers Michael D'Errico
Re: [TLS] Still more on Record Layers Marsh Ray