Re: [DNSOP] Working Group Last Call for draft-ietf-dnsop-dnssec-validator-requirements

[Tim Wicinski <[e-mail]>]

Thanks Daniel.   We've been  waiting for your updated draft.

tim


On Tue, Jan 24, 2023 at 10:14 AM Daniel Migault <[e-mail]> wrote:

> Hi,
>
> If you think I have addressed all comments I received, if you believe that
> is not the case or if there are other comments, please let me know.
> Otherwise I expect to publish a new version by the end of the week.
>
> Yours,
> Daniel
>
> On Fri, Jan 13, 2023 at 5:21 PM Daniel Migault <[e-mail]>
> wrote:
>
>> Hi,
>>
>> I am just wondering if you have any further comments or thoughts or we
>> declare your concerns being addressed. If you think we are fine, just let
>> me know.
>>
>> Yours,
>> Daniel
>>
>> On Tue, Jan 3, 2023 at 7:14 PM Daniel Migault <[e-mail]>
>> wrote:
>>
>>> Hi Vladimir and Florian,
>>>
>>> Thanks for the comment regarding the use of 5011, to update the
>>> trust anchors. There are two situations where TAs need to be updated:
>>> * 1) configuration so the server instances are started with
>>> the up-to-date TA.
>>> * 2) a running resolver instance that has been started with the old TA
>>> and that needs a new TA to be considered.
>>>
>>> 1) configuration:
>>>
>>> TA trust store is an essential element of the configuration, and the
>>> document recommends having a special process to ensure every new resolver
>>> instance starts with the  up-to-date TAs. TAs are so essential in the
>>> elaboration of trust that special care must be considered.  This means that
>>> you need a robust mechanism to update the TAs trust store.
>>> Many DRO will not implement that process and instead rely on software
>>> updates to delegate the TA trust store update to the software vendor.
>>> If the DRO is willing to have a *special/specific* additional TA that is
>>> not updated delegated to the software vendor, the DRO will have to put in
>>> place such a mechanism. This is a critical operation and the DRO must have
>>> strong reasons to do so and must balance the additional operational risks
>>> versus the additional benefits.
>>> Given the essential aspect of the TA trust store, we recommend updates
>>> to be handled by an automated process (as opposed to manually being
>>> performed) BUT we also recommend the process to be manually supervised,
>>> that is with a manual confirmation.
>>> This mechanism is likely to require a specific relation between the DRO
>>> and the TA issuer with potentially the mechanism, being out-of band. To
>>> that point 5011 is probably not the best choice as mentioned by 5011 itself
>>> in section 8.3.
>>>
>>> 2) running servers
>>>
>>> For running resolvers, there is a need to ensure that the resolver is
>>> using the up-to-date TA. For this we recommend to follow 5011 that
>>> indicates how to automatically put significant trust into the newly
>>> published DNSKEY. On the other hand, if resolvers are retarted every days
>>> we may not need to have 5011 and monitor the roll over. I think that is the
>>> purpose of your comment.
>>>
>>> My impression is that there were some confusions in the text where 5011
>>> was used. When it is limited to the running resolver, I would
>>> recommend enabling 5011 when the TA signer implements 5011 in case the
>>> software is not updated in a timely manner - or at least let the DRO decide
>>> whether it is willing to enable this option as a sort of insurance - even
>>> if it is relying on the software update as a general mechanism. I think it
>>> might be a bit different from what you proposed initially, which is to
>>> leave that to DRO with DNSSEC strong expertise and recommend to
>>> only stay with software updates. If there are any strong feelings on just
>>> relying on software updates and leaving 5011 to DNSSEC experts, I am also
>>> fine to push toward such a direction.
>>>
>>> I updated the text as follows:
>>> * clarifying TA updates for configuration versus running instances
>>> * clarifying 5011 dot not apply for updating configuration - at least as
>>> a primary mechanism
>>> * emphasize that the non default model is only recommended for DRO with
>>> DNSSEC expertise
>>> * adding that TA update for running resolver may be performed also by
>>> software update under the condition the DRO is likely to ensure a very
>>> recent release is run.
>>> * add a recommendation that when 5011 is used, the signer needs to
>>> implement 5011 timings.
>>>
>>> The changes can be seen there:
>>>
>>> https://github.com/mglt/draft-mglt-dnsop-dnssec-validator-requirements/commit/dbb75b72a1806520ac77cf04424b0f6de0df29b5
>>>
>>> Yours,
>>> Daniel
>>>
>>> On Sun, Nov 27, 2022 at 7:26 AM Florian Obser <[e-mail]>
>>> wrote:
>>>
>>>> On 2022-11-25 12:26 -05, Daniel Migault <[e-mail]> wrote:
>>>> > On Wed, Nov 23, 2022 at 10:29 AM Vladimír Čunát <
>>>> [e-mail]>
>>>> > wrote:
>>>> >> I am surprised  you would not recommend RFC 5011
>>>> >>
>>>> >> 5011 needs persistent state, a thing that resolvers/validators often
>>>> don't
>>>> >> need at all otherwise (cache is safe to delete).  5011 doesn't
>>>> always work,
>>>> >> so you need to combine with some fallback mechanism(s) anyway - for
>>>> new
>>>> >> installations and for stale ones (missed rotation).  Root rollover
>>>> has
>>>> >> happened only once in history, non-root TAs aren't that common, and
>>>> 5011
>>>> >> algorithm isn't very simple, so the code can easily get some bugs
>>>> without
>>>> >> anyone noticing until it's too late.
>>>> >>
>>>> >> Lots of down-sides, so I rather put the TAs into SW updates, for the
>>>> root
>>>> >> TA case at least.  I'd recommend trying to avoid non-root TAs, but
>>>> if I had
>>>> >> to choose, I'd put them into configuration.  Again a thing that I
>>>> have to
>>>> >> provision *anyway*, so I get the occasional TA updates basically for
>>>> free,
>>>> >> without needing to worry about those 5011 disadvantages.
>>>> (occasional =
>>>> >> 5011 defaults to requiring 30 days of overlap)
>>>> >>
>>>> >>
>>>> > Oh! sure for the TA. My understanding of the text is that it
>>>> recommends
>>>> > 5011 for running instances, but that new instances are configured with
>>>> > up-to-date TA that in most cases are updated by software update. So
>>>> yes I
>>>> > agree and will check this appears clearly.
>>>>
>>>> Another issue with 5011 is that it needs cooperation from the entity
>>>> signing the zone during a KSK rollover. 7583 spells this out in section
>>>> 2.2. I think Vladimír is hinting at this already, I'd say it should be
>>>> spelled out. Especially since this is aimed at non-DNSSEC-Experts as you
>>>> were saying earlier in the thread.
>>>>
>>>> If a DRO unilaterally decides to put in a TA for example.com as
>>>> suggested in section 7.1.1 and using 5011 this will not end well if they
>>>> don't tell the people operating the signer. They will probably not
>>>> follow the correct timing during a KSK roll.
>>>>
>>>
>>>
>>> --
>>> Daniel Migault
>>> Ericsson
>>>
>>
>>
>> --
>> Daniel Migault
>> Ericsson
>>
>
>
> --
> Daniel Migault
> Ericsson
> _______________________________________________
> DNSOP mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/dnsop
>