Re: [kitten] I-D Action: draft-ietf-kitten-rfc6112bis-01.txt
Shawn M Emery <shawn.emery@oracle.com> Wed, 24 August 2016 05:18 UTC
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To: Greg Hudson <ghudson@mit.edu>, kitten@ietf.org
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From: Shawn M Emery <shawn.emery@oracle.com>
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Date: Tue, 23 Aug 2016 23:20:56 -0600
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Subject: Re: [kitten] I-D Action: draft-ietf-kitten-rfc6112bis-01.txt
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On 08/17/16 09:58 AM, Greg Hudson wrote: > On 08/16/2016 12:12 AM, Shawn M Emery wrote: >>> In section 7, "To ensure that an attacker cannot create a channel with a >>> given name" was changed to "To ensure that an attacker cannot create a >>> channel by observing exchanges." The original wording may have used >>> "name" in a non-intuitive way, but I think the new wording is more >>> wrong. The threat is that a MITM attacker might create two channels >>> with the same ticket session key (known to the attacker); the new >>> wording suggests that the threat comes from a passive attacker. >> Yes, the key word "observing" indicates a passive state. How about?: >> >> To ensure that an attacker cannot create a channel by obtaining key >> exchanges between the client and KDC, it is desirable that neither the >> KDC nor the client unilaterally determine the ticket session key. > That still suggests a passive attacker to me. I suggest: > > "To ensure that an active attacker cannot create separate channels to > the client and KDC with the same known key, it is desirable that neither > the KDC nor the client unilaterally determine the ticket session key." I don't think "channels" is the right word in the updated sentence. I interpreted the original text to indicate that an active attacker can not snoop key exchanges between the client and KDC in order to compromise a subsequent secure channel. >>> "By requiring the session key in a way that..." is not grammatical. >>> >> How about?: >> >> This protocol binds the ticket to the DH exchange and prevents the MITM >> attack by requiring the session key in a way that can be verified by the >> client. > I believe that change just reverses the two main clauses of the sentence > without eliminating the grammar error. You could say "requiring the > session key to be created in a way...". Sorry, was focused on the entire sentence. Done. Shawn. --
- Re: [kitten] I-D Action: draft-ietf-kitten-rfc611… Greg Hudson
- Re: [kitten] I-D Action: draft-ietf-kitten-rfc611… Greg Hudson
- Re: [kitten] I-D Action: draft-ietf-kitten-rfc611… Shawn M Emery
- [kitten] I-D Action: draft-ietf-kitten-rfc6112bis… internet-drafts
- Re: [kitten] I-D Action: draft-ietf-kitten-rfc611… Shawn M Emery
- Re: [kitten] I-D Action: draft-ietf-kitten-rfc611… Greg Hudson