Re: [TLS] renego, patricide, putting out to stud, etc.

David-Sarah Hopwood <> Thu, 31 December 2009 20:03 UTC

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Date: Thu, 31 Dec 2009 20:03:20 +0000
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Subject: Re: [TLS] renego, patricide, putting out to stud, etc.
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Ravi Ganesan wrote:
>>> Ravi Ganesan wrote:
>>> ii) A node can create a child node by performing renegotiation, followed by
>>> a full handshake. Such a full-renego-child, starts afresh with new values
>>> for all of the first five parameters. The only parameter which keeps it tied
>>> to this tree is the renegotiation-information, which is derived from the
>>> handshake and the parent-node's renegotiation-information. The primary
>>> use-case for this technique is  to update authentication-knowledge of the
>>> Server (i.e. does it know who the Client is?).  The creation of such a child
>>> node means the parent node can no longer be used.
>> That (the last sentence) is not the case, as far as I'm aware. Renegotiating
>> on some connection currently associated with a session does not mean that
>> that session can no longer be resumed.
> What I meant by 'that node can no longer be used', is that since the
> effective encryption/hashing keys have been rolled over,
> trying to send data using the values in that node to the side should
> not work. In that sense either of the renego child nodes renders its
> parent inactive.

OK, but that's a fairly complicated way of describing the semantics. Also
you used the term "session" to describe the nodes:

# Treating each session as a node in a graph we can get a tree rooted at
# the ROOT.

which is not consistent with "that node can no longer be used", since the
*session* can be reused.

Per connection, the progression of connection states is linear, not a tree,
and that's the simplest way of describing it.

David-Sarah Hopwood  ⚥