Advanced Features Procedure and Test Vector Update

[Wind4Greg]

This PR updates the normative text for the advanced features only. These features are: (a) Anonymous Holder Binding, (b) Credential Bound Pseudonyms, (c) Holder Binding combined with Credential Bound Pseudonyms.

In addition informative test vectors for these advanced features have been updated and an additional "Basic Baseline" test vector set has been added.

---

Preview | Diff

[TallTed]

I've reviewed index.html up to about line 910. The rest requires more focus than I can give for most of the day. I plan to return to it later. That said, the comments I've made may be actionable (which actions might include the later lines of index.html), so I'm submitting this partial review.

Also, I'm trusting that "derived" means that file should not be reviewed, as it's an artifact/output of process (a la, "compiled program"), as opposed to a material input (a la, "source code") that should reviewed.

[TallTed]

Suggested change

	"description": "Government of Utopia Permanent Resident Card.",
	"description": "Permanent Resident Card from Government of Utopia.",

[Wind4Greg]

@TallTed I'm rerunning all the test vectors for the Permanent resident card with the above change (as well as the employment authorization ones).

[Wind4Greg]

@TallTed Thanks for the review up to line 910. This is not as urgent as the other cryptosuites.

[TallTed]

I cannot clean this up, because it's indecipherable. Please try to follow the steps given here, as if you previously had no familiarity with these operations. Particularly important, look at the inputs this operation takes (lines 938-944). |PK|, the original issuers public key, |signature|, the |bbsSignature|, is one style; |header| is the |bbsHeader|, |ph| is the |presentationHeader|, is another. I cannot make these use the same styles as I did in lines 903-913.

[Wind4Greg]

I'm not sure what you're asking for @TallTed, this section should be mapping the W3C VC credential related parameters in the procedure to the IETF/CFRG interface from https://www.ietf.org/archive/id/draft-kalos-bbs-per-verifier-linkability-00.html#name-detailed-proof-generation-w which currently looks like the that shown below. Are you talking about the formatting of the parameters, their meaning, etc...? Also the IETF/CFRG interface maybe updated as the document has been promoted to a CFRG WG document. Hence we may want to wait on precise formatting and parameter naming changes.

proof = ProofGenWithNym(PK,
                        signature,
                        header,
                        ph,
                        nym_secret,
                        context_id,
                        messages,
                        committed_messages,
                        disclosed_indexes,
                        disclosed_commitment_indexes,
                        secret_prover_blind)

Inputs:

- PK (REQUIRED), an octet string of the form outputted by the SkToPk
                 operation.
- signature (REQUIRED), an octet string of the form outputted by the
                        Sign operation.
- header (OPTIONAL), an octet string containing context and application
                     specific information. If not supplied, it defaults
                     to an empty string.
- ph (OPTIONAL), an octet string containing the presentation header. If
                 not supplied, it defaults to an empty string.
- messages (OPTIONAL), a vector of octet strings. If not supplied, it
                       defaults to the empty array "()".
- committed_messages (OPTIONAL), a vector of octet strings. If not
                                 supplied, it defaults to the empty
                                 array "()".
- disclosed_indexes (OPTIONAL), vector of unsigned integers in ascending
                                order. Indexes of disclosed messages. If
                                not supplied, it defaults to the empty
                                array "()".
- disclosed_commitment_indexes (OPTIONAL), vector of unsigned integers
                                           in ascending order. Indexes
                                           of disclosed committed
                                           messages. If not supplied, it
                                           defaults to the empty array
                                           "()".
- secret_prover_blind (OPTIONAL), a scalar value. If not supplied it
                                  defaults to zero "0".


Parameters:

- api_id, the octet string ciphersuite_id || "BLIND_H2G_HM2S_", where
          ciphersuite_id is defined by the ciphersuite and
          "BLIND_H2G_HM2S_"is an ASCII string composed of 15 bytes.

[TallTed]

Here's the rest for index.html (via this PR). Note that a number of these changes likely need to be echoed in the parts of index.html that are not touched by nor accessible through this PR.

[TallTed]

Suggested change

	inclusion of the |signer_nym_entropy| and |featureOption| values, as these
	inclusion of the |signer_nym_entropy| and |featureOption| values, as these

[TallTed]

Suggested change

	|mandatoryPointers|, |signer_nym_entropy| and |featureOption|, as shown below.
	|mandatoryPointers|, |signer_nym_entropy|, and |featureOption|, as shown below.

[TallTed]

Suggested change

	Next the holder uses the the "Verification and Finalization" operation from
	[[CFRG-Pseudonym-BBS-Signature]] to both verify the signature and compute the
	|nym_secret| value. This operation uses the |holder_secret|, |prover_nym|,
	|signer_nym_entropy|, and |secret_prover_blind| values amongst others.
	Next, the holder uses the the "Verification and Finalization" operation from
	[[CFRG-Pseudonym-BBS-Signature]] to both verify the signature and compute the
	|nym_secret| value. This operation uses the |holder_secret|, |prover_nym|,
	|signer_nym_entropy|, and |secret_prover_blind| values, amongst others.

[TallTed]

Suggested change

	Next, the holder needs to indicate what else, if anything, they wish to reveal
	Next, the holder needs to indicate what non-mandatory statements, if any,
	they wish to reveal

[TallTed]

Suggested change

	the inclusion of the computed |pseudonym| and the |featureOption| value.
	the inclusion of the the |featureOption| and computed |pseudonym| values.