On 18.2.2014 17:19, Martin Kosek wrote:
On 02/18/2014 04:38 PM, Jan Cholasta wrote:
On 18.2.2014 16:35, Petr Spacek wrote:
On 18.2.2014 16:31, Jan Cholasta wrote:


2] low level replacement for eg the sqlite3 database in softhsm.
That's what I sometimes get the impression what is wanted. SoftHsm has
one component Softdatabase with an API, which more or less passes sets
of attributes (attributes defined by PKCS#11) and then stores it as
records in sql where each record has a keytype and opaque blob of
data.
If that is what is wanted the decision would be how fingrained the
pkcs
objects/attribute types would have to be mapped to ldap: one ldap
attribute for each possible attribute type ?

One-to-one mapping of attributes from PKCS#11 to LDAP would be the most
straightforward way of doing this, but I think we can do some
optimization for our needs. For example, like you said above, we can
use
a single attribute containing PKCS#8 encoded private key rather than
using one attribute per private key component.

I don't think we need an LDAP attribute for every possible PKCS#11
attribute, ATM it would be sufficient to have just these attributes
necessary to represent private key, public key and certificate objects.

So, I would say it should be something between high-level and
low-level.

There won't be a separate public key, it's represented by the
certificate.

I'm not sure if this is the case for DNSSEC.

Honzo,

we really need the design page with some goal statement, high-level
overview etc. There is still some confusion, probably from fact that we
want to use the same module for cert distribution and at the same time
for DNSSEC key storage.


It's on my TODO list, I'll try to get it out ASAP.


+1, please do. We clearly need some design to start with.

Martin


I already posted the link in other thread, but here it is anyway: <http://www.freeipa.org/page/V3/PKCS11_in_LDAP>.

Some more comments on the schema:

I think I may have been too quick to dismiss RFC 4523. There is CKA_CERTIFICATE_CATEGORY which can have values "unspecified", "token user", "authority" and "other entity". We could map entries with object class pkiUser to certificate object with CKA_CERTIFICATE_CATEGORY "token user" and entries with object class pkiCA to certificate object with CKA_CERTIFICATE_CATEGORY "authority". There are no object classes in RFC 4523 for "unspecified" and "other entity", but we will not be storing any certificates using PKCS#11 anyway, so I think it's OK.

Also the above got me thinking, is there any "standard" LDAP schema for private keys? If so, can we use it?

I'm going to store NSS trust objects along with CA certificates, so I'm going to need an object class for that. You can find the details on CKO_NSS_TRUST at <http://p11-glue.freedesktop.org/doc/storing-trust-policy/storing-trust-existing.html>.

If we store multiple related PKCS#11 objects in a single LDAP entry, there is going to be some redundancy. For example, public key value can be extracted from private key value, so we don't need to store both of the values. This can be bypassed by having separate object classes for data and for metadata. For a key pair entry, the object classes would be e.g. privateKey, pkcs11privateKey and pkcs11publicKey, where privateKey is an object class with private key data (without any PKCS#11 bits), pkcs11privateKey is an object class with PKCS#11 private key metadata and pkcs11publicKey is an object class with PKCS#11 public key metadata. In the PKCS#11 module, this entry would be visible as two separate objects (private key object and public key object).

Regarding PKCS#11 metadata attributes (i.e. excluding certificate, private key and public key value attributes), I think they all should be single-valued. Comments on specific attributes:

* CKA_MODIFIABLE, CKA_SUBJECT, CKA_ISSUER, CKA_SERIAL_NUMBER, CKA_JAVA_MIDP_SECURITY_DOMAIN, CKA_DERIVE, CKA_LOCAL, CKA_KEY_GEN_MECHANISM, CKA_ALLOWED_MECHANISMS, CKA_VERIFY_RECOVER, CKA_SIGN_RECOVER, CKA_ALWAYS_SENSITIVE, CKA_NEVER_EXTRACTABLE, CKA_WRAP_WITH_TRUSTED, CKA_ALWAYS_AUTHENTICATE - there should be LDAP attributes for these, for the sake of completeness

* CKA_TOKEN - this is CK_TRUE for persistent objects and objects in LDAP are always persistent, so there is no need for pkcs11token

* CKA_CERTIFICATE_TYPE - this will always be CKC_X_509, no need for pkcs11certificateType

* CKA_CERTIFICATE_CATEGORY - if this is mapped to RFC 4523 object classes (see above), we don't need an LDAP attribute for it

* CKA_CHECK_VALUE, CKA_HASH_OF_SUBJECT_PUBLIC_KEY, CKA_HASH_OF_ISSUER_PUBLIC_KEY - can be generated on-the-fly from certificate value, no need for LDAP attributes

  * CKA_URL - do we want to support certificates with URL instead of value?

--
Jan Cholasta

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