Resolve the mgmt-key algorithm by probing

[episource]

Currently keyroost uses the management key algorithm reported by GET METADATA. This is a yubico extension APDU. For cards not supporting this extension, 3-DES was used unconditionally. This PR adds probing if GET METADATA is not implemented by the card/token.

[episource]

Cryptnox OpenFIPS201 variant uses AES management as default, but does not implement yubico extension command GET METADATA. Setting management key for this type of card enabled by cryptnox/cryptnox-id-cli#12 .

[framefilter]

Thanks @episource, this closes a known gap.

Two questions:

1. Which hardware did you verify on? If it was the Cryptnox OpenFIPS201: did the card reject the wrong P1s at step 1, or accept all four and fall through to the key-length table?
2. Any objection to dropping PivSession::management_key_algorithm in a follow-up? It has no callers left.

I pushed two commits on top of yours: 1dd8bbb narrows the CLI's map_err to PivBadKeyLength so a transport failure mid-probe isn't reported as a wrong-length key, and corrects the comment above it; 8003c34 adds the changelog fragment. Let me know if there's anything that doesn't meet your intent, happy to revisit.

[episource]

Thanks for catching cli's error handling being to broad.

I've indeed tested management auth with a Cryptnox PIV card. The vendor claims this card uses plain OpenFIPS201 v2 as certified per Nist CMVP #5280. I bought this card for OpenFIPS201 v2 testing.

I've only done management key GENERAL AUTHENTICATE tests using this card and was able to use Keyroost to successfully authenticate and create a key on that device. Didn't do any further tests with the Cryptnox card, therefore I wouldn't claim these cards fully supported (though more functionality might work, just not tested).

Also consider, the default cryptnox-id (pre) perso sequence does not initialize the slot 9B management key object. The cryptnox-id's default way is SCP03 admin commands only, not the PIV standard PUT DATA and GENERATE ASYMMETRIC KEY commands protected by 9B-management-key backed GENERAL AUTHENTICATE. Keyroost however relies on the PUT DATA/GENERATE ASYMMETRIC KEY commands. OpenFIPS201 v2 has full support for this, but the currently released cryptnox tooling does not even support initializing the 9B key. I've created cryptnox/cryptnox-id-cli#12 to add this. Without 9B-management-key set, the PIV standard PUT DATA/GENERATE ASYMMETRIC KEY commands are blocked!

For my tests I've used below cryptnox profile. It's derived from cryptnox-default profile, but disables contactless restrictions (contact & contactless configured equally).

# this profile configures contactless equal to contact
# otherwise equal to cryptnox-default
name: contactless-no-sm
mode: developer-not-for-production
admin:
  key_ref: 9B
  mechanism: AES256
pin:
  min: 6
  max: 8
  retries: 6
  charset: numeric
puk:
  min: 8
  max: 8
  retries: 6
  charset: numeric
containers:
- oid: 5FC102
  name: chuid
  contact: ALWAYS
  contactless: ALWAYS
- oid: 5FC107
  name: ccc
  contact: ALWAYS
  contactless: ALWAYS
- oid: 5FC105
  name: auth-cert
  contact: ALWAYS
  contactless: ALWAYS
- oid: 5FC101
  name: card-auth-cert
  contact: ALWAYS
  contactless: ALWAYS
- oid: 5FC10A
  name: sign-cert
  contact: ALWAYS
  contactless: ALWAYS
- oid: 5FC10B
  name: keymgmt-cert
  contact: ALWAYS
  contactless: ALWAYS
- oid: 5FC106
  name: security-object
  contact: ALWAYS
  contactless: ALWAYS
- oid: 5FC103
  name: fingerprints
  contact: PIN
  contactless: PIN
- oid: 5FC108
  name: facial
  contact: PIN
  contactless: PIN
- oid: 5FC109
  name: printed
  contact: PIN
  contactless: PIN
keys:
- ref: 9B
  name: admin
  mechanism: AES256
  role: AUTHENTICATE
  contact: ALWAYS
  contactless: ALWAYS
  attributes:
  - PERMIT_EXTERNAL
  - PERMIT_MUTUAL
  - IMPORTABLE
- ref: 9A
  name: auth
  mechanism: ECCP256
  role: AUTHENTICATE
  contact: PIN
  contactless: PIN
  attributes:
  - IMPORTABLE
- ref: 9C
  name: sign
  mechanism: ECCP256
  role: SIGN
  contact: PIN
  contactless: PIN
  attributes:
  - IMPORTABLE
- ref: 9D
  name: keymgmt
  mechanism: ECCP256
  role: KEY_ESTABLISH
  contact: PIN
  contactless: PIN
  attributes:
  - IMPORTABLE
- ref: 9E
  name: card-auth
  mechanism: ECCP256
  role: AUTHENTICATE
  contact: ALWAYS
  contactless: ALWAYS
  attributes:
  - IMPORTABLE