It would also be good if the correct acronym could be used in emails as it 
makes it easier to track down what people are referring to.

Jonathan

> -----Original Message-----
> From: Brian E Carpenter [mailto:brian.e.carpen...@gmail.com]
> Sent: 08 November 2016 05:09
> To: jonat...@hansfords.net; Toerless Eckert <t...@cs.fau.de>; Max Pritikin
> (pritikin) <priti...@cisco.com>
> Cc: Toerless Eckert <tte+i...@cs.fau.de>; Anima WG <anima@ietf.org>; Eliot
> Lear <l...@cisco.com>
> Subject: Re: [Anima] Desaster recover...
> 
> Jonathan,
> 
> BRSKI (I not Y) is defined in draft-ietf-anima-bootstrapping-keyinfra-04
> "Bootstrapping Remote Secure Key Infrastructures (BRSKI)". If there are
> incomplete or incorrect references in other documents, of course they need
> to be completed or corrected.
> 
> Regards
>    Brian
> 
> On 07/11/2016 21:42, jonat...@hansfords.net wrote:
> > Hi,
> >
> > Following ANIMA in fits and starts and saw the reference to BRSKY. Tried to
> follow up on what it was all about and found the reference to it in 
> draft-ietf-
> anima-autonomic-control-plane-04. Section 5.2.4 is entitled “Discovery and
> BRSKY” but appears to make no reference to it and, despite three uses of the
> term BRSKY in the document, I find the protocol is actually the Bootstrapping
> Remote Secure Key Infrastructures (BRSKI).
> >
> > Is the intention to rename to BRSKY or is it just that people have got into
> the habit of calling it that?
> >
> > Jonathan
> >
> > =O)
> >
> > From: Toerless Eckert
> > Sent: 07 November 2016 06:01
> > To: Max Pritikin (pritikin)
> > Cc: Toerless Eckert; Eliot Lear; Anima WG
> > Subject: Re: [Anima] Desaster recover... (was: Re: [homenet] write up
> > oftime without clocks)
> >
> > On Fri, Nov 04, 2016 at 09:23:15PM +0000, Max Pritikin (pritikin) wrote:
> >> There is a lot here. Attempting to comment on it all.
> >>
> >> It would really help if we could relate these discussions to specific text
> sections that could be improved. Otherwise we???re just blowing into the
> wind. (Where it seems obvious I???ve added such notes).
> >
> > Sure, but lets high level agree what type of content is useful and
> > where it would fit.
> >
> >>> - Large organizations will have spares. With ANIMA, those spares
> >>> should  be stored pre-enrolled to avoid MASA/registrar dependency
> >>> during
> >>>  recovery/replacements: Receive gear on any site (no central
> >>> provisioning  site needed), but unpack, plug in for short period, then
> stash away.
> >>
> >> Devices that have been brought up and are in the network post bootstrap
> are not relevant to the BRSKI document.
> >
> > To me the most important goal should be to provide candidate users
> > with deployment guidance. This should fit ANIMA goals given how its an
> OPS group.
> >
> > Lets say we have two options:
> >
> >   a) keep spares unenrolled, enrol during desaster recovery with satellite
> link
> >   b) enrol spare devices when they are stocked, deploy during desaster.
> >
> > lets assume we agree both are relevant deployment options that users
> > should understand, compare pro/cons for their case and choose. If you
> > think we can not mention both in the BRSKY spec, then i think it would
> > be better to have a separate document where both could be discussed.
> >
> >>>  This is imo an easy requirement also useful without desaster
> >>> requirements
> >>>  - aka: enrolled spares would likely also have better theft/abuse
> >>> protection  than non-enrolled. And yes, you will have to power up
> >>> these spares  once a year. Which IMHO is ok. And of course certs
> >>> should therefore  be somewhat longer than 1 year).
> >>
> >> This could be captured as a discussion: what does a device do when its
> credentials are out of date? Does it fall back on full bootstrapping? If so 
> this
> becomes a potential attack vector wherein the attacker can convince the
> device it is out of date and then force it to restart bootstrapping. That 
> would
> be bad.
> >
> > Haha... ;-) i just wanted to show what IMHO are the most simple
> > deployment options to deal with desaster recover. Now you're the one
> > who is opening another round of discussions trying to figure out the
> > best security compromise for those deployment processes.  Which is great.
> > Just don't blame me that there are more and more interesting details
> > to capture somewhere.
> >
> >> So, should there be an injection point into the bootstrapping state
> machine that says something like:
> >>
> >> If a device fails to join the ANI after [some number] of attempts it
> attempts to repeat bootstrapping using its original SUDI credentials.
> >
> > I'd prepare a flag 'operational' set by SDN controller or ASA after
> > the device is "provisioned" (config/intent applied).
> >
> >> During this bootstrapping attempt it MUST only bootstrap on a Registrar
> that provides both a valid voucher and an identity recognizably within the
> same PKI hierarchy the device was in previously. This is detected by the
> device by either (a) the domainCAcert is an exact match for the current
> domain trust anchor known to the device or (b) the EST /cacerts response
> includes a chain that terminates in the current domain trust anchor known to
> the device.
> >>
> >> This extends the lifetime of such a stored device beyond its own
> certificate (maybe 1 year) *and* beyond the current CA certificate (maybe a
> 2year cert) an all the way into the next CA certificate (another 2 years). 
> That
> is a pretty solid lifetime (up to 4 years) for recovery.
> >
> > Interesting thought.
> >
> > a) Would like to understand how this compares to just making certs
> > longer-lived, eg: 3 years, but doing normal renewal after 30% time.
> >
> > b) Seem like there's quite a bit of analysis to be done of how
> > different parameter/options will work together:
> >   - device with/without reliable RTC
> >   - what would be necessary/beneficial with nonce-less vouchers ?
> >     how about nonceless vouchers with sequence number... -> remember
> >     ownership voucher and allow for it to be replaced only with one that
> >     hass a higher serial number.
> >
> >>> - If sparing would be cross-locations (eg: spares sent from some
> >>> site to  other sites during recovery), then its important that the
> >>> ANIMA certs do  not include any location specific attributes that
> >>> would prohibit thart  movement. So far BRSKY does not include any
> >>> such attributes, but in  discussions, three has been interest to
> >>> lock into the cert some device  role specific attributes, and for a
> >>> spare piecce of equipment, those  attributes may not be
> predetermined.
> >>>
> >>>  Aka: Desaster sparing means domain certs need to be simple, devices
> >>> reuseable across domain.
> >>
> >> I agree that certs should include the absolute minimum information about
> the device. The actual ID is sufficient in my book. Attribute Certs or backend
> database lookups or short term tokens obtained by the device in place are all
> methods of distributing additional information.
> >
> > Desaster recovery seems to be one good motivation to not put more than
> > the minimum into the certs. I was a fan of putting more into certs in
> > the past...
> >
> >>> - If spares are done by a shared facility: vendor, FEMO (for fed
> >>> networks)  or the like, one could think of that entity offering
> >>> (emergency)  enrolment service.
> >>>
> >>>  Such an entity would have desaster proof MASA connectivity on site,
> >>> and the customers would provide it with (emergency) registrar certs.
> >>
> >> Ok. So like a Cisco NERV truck that provides connectivity sufficient to
> rebuild a network in place.
> >>
> >> Issuing a new Registrar ID would mean being able to bring up the PKI
> infrastructure during the recovery process. But this is exactly the time 
> period
> when having as much of the critical keying infrastructure offline and secured
> could be beneficial for longterm security. One could argue that extra
> attempts should be made to ensure the PKI is offline.
> >
> > My thought was
> > a) the desaster recovery registrar-IDs are preprovisioned _before_
> desaster
> >    (contract between domain and desaster/spare recovery entity).
> > b) The facility to which they are allocated is shared across multiple
> >    domains.
> > c) the facility is not "desaster on-site" -> the spares will not be on-site,
> >    but will be stored at some central site. Enrollment would happen at
> >    that central site, then they'd be shipped onto-desaster-site.
> >
> >>>  (emergency) meaning that the entity is only permitted to enrol
> >>> during  emergencies, and the customer could be able to verify the
> >>> emergency  entities behavior by pulling from the MASA an audit log.
> >>
> >> Section 5.6 doesn???t include the Registrar identity only the domainID in
> the log. Do folks think the Registrar ID should be included as well?
> >
> > Oh, right. i confused domain-id with registrar-ID.
> >
> > I definitely think registrar-ID would be necessary to log so that
> > audit-logs become more useful to backtrack what happened.
> >
> >> If this was done then does it matter if the Registrar cert has role
> information in it? As per the above what would happen if all devices in the
> ANI could act as a registrar? There would be a higher chance that one of
> them would mess up and actually perform registrar activities incorrectly ???
> but it would be logged so the admin could watch for that.
> >
> >
> > I don't think we need many/all devices to be registrars. I don't think
> > we've got a working security model to do this anyhow - eg:
> > authenticating all those devices against the CA. I hope we do not need
> > to discuss other roles beside "registrar" in this context.
> >
> >> Thoughts? I???m worried but see the conversation going that way.
> >
> >>>  If the customer would give the emergeny registrar credentials
> >>> cert/private/public-key to the emergeny entities, then the customer
> >>> itself also has the cert/private-key and could ask the MASA.
> >>>  This option would work with current BRSKY text. I am just not sure
> >>> about security BCP (having two copies of a public key pair???).
> >>
> >> Sorry - I can???t write text around copying a private key. If we???re going
> that route lets dump all the PKI stuff and just use bearer tokens and be up
> front about the security we???re providing. See above for different ideas.
> >
> > Yepp. There should be easier options to achieve the same goal.
> >
> > Eg: I create a registrar as a VM, and run it onprem of the desaster
> > recovery provider so that provider can enroll devices for my domain in
> > case there is a desaster in my domain.
> >
> >>> - If the shared spare storage facility is Best Buy, and the Jones
> >>> family wants to replace some electric storm victims @home while
> >>> their ISP takes its days (my ISP C*...*T took almost 48 hours in one
> >>> case),  then the gear should probably come with a nonceless voucher
> >>> printed on on a scratcher piece of paper inside the box.
> >>
> >> Even a nonceless voucher includes the domainCAcert so this idea
> doesn???t fly with the current text. What you???re looking for is some form
> of ???bearer voucher??? that contains a symmetric key.
> >
> > Probably. Yes. I guess we have not discussed how to apply BRSKY
> > enrollment for home users. It's outside of scope for ANIMA anyhow, but
> > would be interesting. Some of those home thoughts likely equally apply
> > to low-end IoT devices.
> >
> >> Anybody who can scan it off the box can deploy the device.
> >
> > Thats why i said "scratcher", eg: some one-time-unveil where you can
> > easily check that its untampered when you buy the device.
> >
> >> I???d normally rail against this but am actually pleased to see it fit so 
> >> well
> into the model. A bearer voucher sorta sucks but creating one didn???t
> change any of our messaging flow or anything. Interesting positive that???
> >
> >> I???m thinking that it is time for a section 3.7 ???Voucher types??? that
> digs into what we???re talking about for these different voucher types.
> Currently the text is scattered in the other sections.
> >
> > We could also start discussing those aspects in the submission from
> > Kent et. al. about vouchers and move into BRSKY when we see it fit.
> >
> > Cheers
> >     Toerless
> >
> >> - max
> >>
> >>> Beyond these BRSKY considerations, the next cool ANIMA piece to
> >>> consider for these use-cases is of course the ASA driven
> >>> "re-configuration" of the spare device, aka: In larger outages, you
> >>> should not except the whole network provisioning backend to be up
> >>> and running. And its IMHO illusionary to expect devices to ONLY be
> >>> driven from intent for many years (in complex networks... in a clean
> >>> homenet they are driven by intent today..).
> >>>
> >>> Aka: for pre-intent-only desaster proof networks, we'd need:
> >>>  - ASA to cache neighbors configs.
> >>>  - reapply neighbor stored config when replacement gear is inserted.
> >>>  - IMHO: An anima definition for a "device-role-id" which is not
> >>>    the ACP IPv6 address (which will change upon gear replacement
> >>>    without enrolment support).
> >>>
> >>> Cheers
> >>>    toerless
> >>
> >
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> >
> >
> >
> >
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> >


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