Hi all, Iâve uploaded my latest version of the HSS Spec. It isnât quite in its finished form as I have a few questions. Iâll describe the changes I made here â if something is different than what was intended please let me know! - Removed HSS_PARAMS from the public key object since this information isnât even available from the public key.
- Added CKA_LEVELS, CKA_LMS_TYPE, and CKA_LMOTS_TYPE attributes to the public key object with the assumption that the device will parse the public key and make these values easily available to the application. The latter two attributes are the information about the top level tree which is contained in the public key, and which the application might use to decide what it thinks the security level of the scheme is.
- Added CKA_HSS_LEVELS, CKA_LMS_TYPES, and CKA_LMOTS_TYPES attributes to the private key object. The latter to attributes are of type CK_ULONG_PTR.
- Removed CKA_HSS_PARAMS from the private key object as we now return its contents in separate, more conveniently accessible attributes.
- Added CKA_KEYS_REMAINING to the private key object.
- Modified the sample private key template to contain the new CK_HSS_LEVELS, CK_LMS_TYPES, and CK_LMOTS_TYPES.
- Switched from using âCK_LMOTS_TYPEâ and âCK_LMS_TYPEâ to âCK_ULONGâ since I donât think there is a need for a special typedef. (?)
- Added CKA_KEYS_REMAINING attribute to the private key object. (Not sure this is the right way to do it, please see my question below.)
- Modified the description of mechanism contributions in the HSS key pair generation section.
Questions: - For the sample template for creating an LMS private key object, should we be passing in the CKA_VALUE? What would it contain when the template is used for key generation?
- Should CKA_KEYS_REMAINING be an attribute in the private key object, or should there be a separate mechanism that returns it (since it changes with use)?
- I was not sure exactly how to give the example input for the CK_ULONG_PTR inputs ÂlmsTypes and lmotsTypes in the template. I used â[{123],â]â. Is there a better choice?
- I wasnât sure if I should call the levels attribute âCKA_LEVELSâ or âCKA_HSS_LEVELSâ. (I was actually inconsistent from table to table in this as well.) What would be best? Similarly for âCKA_LM(OT)S_TYPESâ vs âCKA_HSS_LM(OT)S_TYPESâ.
The only new definition that is needed is the CKA_KEYS_REMAINING attribute, of type CK_ULONG. I also need to let you all know that I will be moving to a different industry (biometric data!) in a few weeks, so May 14 will be my last day with ISC. Iâve enjoyed working with all of you and I really appreciate all the support you have given me in developing the HSS spec! Iâm hoping I can get it into final form â or at least a form where only a few tweaks will be needed before I leave! 😊 Michelle |