[Freeipa-devel] DNSSEC design page

[Simo Sorce]

On Tue, 2014-02-25 at 13:22 -0500, Rob Crittenden wrote:
> Jan Cholasta wrote:
> > On 25.2.2014 17:36, Ludwig Krispenz wrote:
> >>
> >> On 02/25/2014 05:12 PM, Simo Sorce wrote:
> >>> On Tue, 2014-02-25 at 16:18 +0100, Jan Cholasta wrote:
> >>>> On 25.2.2014 16:11, Simo Sorce wrote:
> >>>>> On Tue, 2014-02-25 at 15:59 +0100, Petr Spacek wrote:
> >>>>>> On 25.2.2014 15:11, Simo Sorce wrote:
> >>>>>>> On Tue, 2014-02-25 at 14:54 +0100, Ludwig Krispenz wrote:
> >>>>>>>>> Any reason why we should follow in detail what softshm does ?
> >>>>>>>> because I did't know what is really needed. If you want to have a
> >>>>>>>> pkcs11
> >>>>>>>> module, which stores data in ldap, I though it should have all the
> >>>>>>>> attributes potentially needed.
> >>>>>>>> Jan said taht OpenDNSSEC uses CKA_VERIFY, CKA_ENCRYPT, CKA_WRAP,
> >>>>>>>> CKA_SIGN, CKA_DECRYPT, CKA_UNWRAP, CKA_SENSITIVE, CKA_PRIVATE,
> >>>>>>>> CKA_EXTRACTABLE,
> >>>>>>>> so there is at least one requirement for fine grained attributes.
> >>>>>>> Does OpenDNSSEC store them as separate entities and need access
> >>>>>>> to them
> >>>>>>> independently ?
> >>>>>> AFAIK OpenDNSSEC uses purely PKCS#11 for key manipulation so LDAP
> >>>>>> schema
> >>>>>> doesn't matter as long as our PKCS#11 module can derive all values
> >>>>>> defined by
> >>>>>> standard.
> >>>>>>
> >>>>>> Honza, you did investigate OpenDNSSEC integration, please add some
> >>>>>> details if
> >>>>>> you can.
> >>>>>>
> >>>>>>> Or is this internal use that can be satisfied by unpacking a blob in
> >>>>>>> OpenDNSSEC ?
> >>>>>>>
> >>>>>>> What does bind9 uses ? Petr, can you provide example key files ?
> >>>>>> Private+public keys stored in files:
> >>>>>> https://www.redhat.com/archives/freeipa-devel/2014-February/msg00463.html
> >>>>>>
> >>>>>>
> >>>>>> Private keys stored in HSM and public keys in files:
> >>>>>> https://www.redhat.com/archives/freeipa-devel/2014-February/msg00333.html
> >>>>>>
> >>>>>> (I.e. some values in .private file are replaced by PKCS#11 label.)
> >>>>> Ok it seem clear to me we do not need to spell out a lot of values
> >>>>> when
> >>>>> using pkcs#11 as bind doesn't need them in the key files. So I
> >>>>> assume it
> >>>>> can query the pkcs#11 module to find what it needs.
> >>>>>
> >>>>> I would use these key files as a sort of guide to understand what we
> >>>>> need in LDAP. I would try to put in a single blob as much as we can
> >>>>> that
> >>>>> we do not explicitly need by a client querying LDAP directly.
> >>>>>
> >>>>> I think in order to nail down exactly what we need, at this point, we
> >>>>> require some example use cases and queries the various clients would
> >>>>> perform with spelled out what they are looking for to identify or
> >>>>> manipulate keys.
> >>>>>
> >>>>> Simo.
> >>>>>
> >>>> See "How applications interact with PKCS#11" at
> >>>> <http://www.freeipa.org/page/V3/PKCS11_in_LDAP>. Tl;dr: applications
> >>>> don't search for keys by key data, but by metadata, so like I said in
> >>>> the other thread, key data can be in a single blob, but metadata should
> >>>> be in separate attributes.
> >>> Ah sorry, I hadn't looked at that one yet.
> >>> It helps quite a bit.
> >>>
> >>> So are the class, key_type, id, label, token, 'sign' the only values we
> >>> should really care to split off ?
> >
> > They are all metadata related to PKCS#11 operation. I don't think you
> > can easily encode them in PKCS#8 or certificate blob, so they actually
> > need to be split off. You can find the full list of them in the PKCS#11
> > spec (link below).
> >
> >>>
> >>> Can you describe what are these values ?
> >>> What is class ? Why is it important, and how does it differ from
> >>> key_type ?
> >>> What is the token ? What is 'sign' ?
> >>>
> >>> Feel free to give references to specific documents to read up about
> >>> these attributes.
> >> I'm a newcomer to this area and am orienting myself at this doc:
> >> ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-11/v2-30/pkcs-11v2-30b-d6.pdf
> >> and looking into opendnssec andsofthsm code.
> >
> > I use mainly
> > <ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-11/v2-20/pkcs-11v2-20.pdf>, as
> > 2.30 is a draft ATM.
> >
> >>
> >> It explains CKA_SIGN as:
> >> "TheCKA_SIGN attribute of the signature key, whic h indicates whether
> >> the key supports signatures with appendix, must be CK_TRUE."
> >> I cannot tell if this will be needed, just can make up an attribute and
> >> allow it in an objectclass :-)
> >
> > OpenDNSSEC puts it in public key objects it generates, so it's needed at
> > least for the sake of it.
> >
> > Actually, I think we should support all of the metadata attributes, so
> > that our PKCS#11 module is reasonably generic and not tailored to needs
> > of a specific consumer.
> 
> We could hardcode some of these values but it will very likely cause 
> problems later. It seems simple enough to just define schema for all of 
> them and store them, except perhaps in the cases where they are easily 
> derived. If we, for example, store the prime numbers and exponents, they 
> need to be protected as carefully as the private key.

This is something I meant to discuss too, how do we protect them ?
Clearly we have ACIs but I am wondering if we want to encrypt them with
keys not immediately or easily available via LDAP ?

It's kind of catastrofic if they get inadvertently exposed like if
someone does a ldapsearch as "Directory Manager", which is one of the
reasons why we encrypt kerberos key material before storing it into the
db.

Simo.

-- 
Simo Sorce * Red Hat, Inc * New York