[secdir] MTI ... Re: Security review of draft-ietf-oauth-dyn-reg-management-12

[Hannes Tschofenig <[e-mail]>]

Hi Ben,

I would like to respond to this issue:

On 04/01/2015 02:29 PM, Ben Laurie wrote:
> Issue: "The server MUST support TLS 1.2" - it seems unwise to mandate
> a particular version of TLS - work on TLS 1.3 is already under way,
> and TLS 1.2 is not (it seems) that far off deprecation!

We had a lengthy debate in OAuth around the issue of
mandatory-to-implement security functionality. Earlier we just pointed
to the use of TLS but then the question arises what version of TLS and
what ciphersuites to use.

Then, we came up with this text for all of our documents but it creates
the problem you outlined. In essence, all our documents will point to an
old TLS version in approx. 1 year from now when TLS 1.3 is finalized.

I believe this is a broader issue that needs to be solved in the
security area and not just with OAuth, namely should specifications
contain MTI security functionality when we know already at the time of
writing that they will be outdated within a reasonable amount of time?
In some sense, I see a bit of overlap with the crypto agility debate and
the attempt to reduce the overhead for standardization in introducing
new cryptographic algorithms.

I personally would like to replace these types of recommendations with
references to a page on the IETF website that talks about the most
recent TLS & ciphersuite recommendations. I am aware that this might
create problems with claiming interoperability with a specific RFC...

Help appreciated.

Ciao
Hannes