[CFRG] Re: Call for Adoption of Blind BBS and BBS Pseudonyms

["Lysyanskaya, Anna" <[e-mail]>]

Hi Greg et al (and the CFRG community),

Thank you so much for all the work that you are doing to standardize and
implement the BBS family of anonymous credentials!

I don't want to repeat everything that we (cryptographers) have already
expressed last summer in the "Cryptographers' feedback" you link to below,
but just wanted to mention the key point that out consensus opinion was
that BBS is the most mature approach to a privacy-preserving identity
"wallet" and so the work you are doing is a key step towards realizing any
viable -- from both the security and the privacy point of view -- solution
to digital identity.

Thank you!

:)

Anna


On Mon, 18 November 2024 16:43 UTC  Greg Bernstein <
[e-mail]> wrote:

Thanks for providing the extensive references including links to EUDI
> materials Orie. I particularly recommend the Cryptographers’ Feedback
> <https://github.com/user-attachments/files/15904122/cryptographers-feedback.pdf>
> for those with limited time and looking for a cryptographic perspective.
>
> I’ve prepared some draft background text on pseudonyms
> <https://github.com/Wind4Greg/bbs-per-verifier-id/blob/notes-app-hist/app-history-notes.md>
> (history general applications) that may be incorporated into the next
> revision of the draft.
>
> Code that most closely matches the current BBS pseudonym draft
> <https://www.ietf.org/archive/id/draft-kalos-bbs-per-verifier-linkability-00.html#>
> can be found in https://github.com/Wind4Greg/grotto-bbs-signatures/blob/blind-pseudo-update/lib/PseudonymBBS.js.
> This is currently on a different branch from main. There are unit and
> consistency tests in https://github.com/Wind4Greg/grotto-bbs-signatures/tree/blind-pseudo-update/pseudonym_test.
> I have not updated the pseudonym examples yet to reflect the API and
> capabilities of the latest draft. Note that this is *not* a production
> implementation, but a straightforward implementation of the draft in
> JavaScript. Vasilis tends to work in Rust and we produce and check test
> vectors in both languages (BBS, Blind BBS, and soon BBS pseudonyms).
>
> Cheers Greg
>
> On 11/18/24 6:31 AM, Orie Steele wrote:
>
> > A few references related to pseudonyms and digital credentials:
> >
> > -
> > https://eu-digital-identity-wallet.github.io/eudi-doc-architecture-and-reference-framework/1.4.0/annexes/annex-2/annex-2-high-level-requirements/#a2311-topic-11-pseudonym-attestation
> > -
> > https://github.com/eu-digital-identity-wallet/eudi-doc-architecture-and-reference-framework/blob/main/docs/arf.md#53-attestation-rulebooks
> >
> > -
> > https://github.com/eu-digital-identity-wallet/eudi-doc-architecture-and-reference-framework/discussions/192
> > -
> > https://github.com/eu-digital-identity-wallet/eudi-doc-architecture-and-reference-framework/discussions/211
> > - https://github.com/WICG/digital-credentials/issues/126
> >
> > Some discussion on IETF lists:
> >
> > - https://mailarchive.ietf.org/arch/msg/oauth/GLWRrHziS6cxujzqm2dEjwNzF2c/
> > - https://mailarchive.ietf.org/arch/msg/jose/wStUxR4nv01SkNHjsfILyqhOpSE/
> > -
> > https://mailarchive.ietf.org/arch/msg/privacy-pass/RHHA0DfN7RvJ_2Ai6V0AyL_FzvM/
> >
> > Background:
> >
> > -
> > https://ec.europa.eu/digital-building-blocks/sites/display/EUDIGITALIDENTITYWALLET/EU+Digital+Identity+Wallet+Home
> > -
> > https://commission.europa.eu/strategy-and-policy/priorities-2019-2024/europe-fit-digital-age/european-digital-identity_en
> >
> > I spent some time this weekend looking at the implementations I could
> > easily find of pseudonyms draft:
> >
> > https://github.com/Wind4Greg/grotto-bbs-signatures/blob/main/lib/PseudonymBBS.js
> >
> >
> > I found it difficult to understand how to construct a high level API
> > that could do better than batch issuance of one time use SD-JWT /
> > SD-CWT / ISO mDoc.
> >
> > I was hoping for something simple (small code example) explaining key
> > generation, identifier construction, attribute binding to identifiers,
> > presentation of attributes to a verifier, verification of presented
> > attributes.
> >
> > It would be nice to see an interface that supported some agility,
> > maybe even beyond pairing friendly curves describes here:
> > https://datatracker.ietf.org/doc/draft-irtf-cfrg-pairing-friendly-curves/
> >
> > Ideally we would be able to get "directed identifiers / pseudonyms" to
> > generalize to a few HSM supported crypto systems, RSA, EC, Lattices,
> > similar to how KEMs have been abstracted.
> >
> > That way there could be a PQ migration path for pseudonyms... on the
> > other hand, maybe going for an abstraction / framework upfront is a
> > mistake and we should gain some experience with these systems
> > separately before trying to generalize them.
> >
> > OS
> >
> >
> >
> > On Sun, Nov 17, 2024 at 3:38 PM Stephen Farrell
> > <[e-mail]> <&lt;[e-mail]&gt;> wrote:
> >
> >
> >     Hiya,
> >
> >     On 17/11/2024 18:51, John Bradley wrote:
> >     >
> >     > These are features that will be critical for BBS to be adopted for
> >     > the EUDI ecosystem.
> >     >
> >     > A number of pilots, including one for age verification in the EU,
> >     > are starting soon.
> >     >
> >     > Without progress, we are likely to see ISO mDoc as the dominant
> >     > solution with all the privacy problems that it will entail.
> >
> >     Can you provide references easily? That'd help to take a position
> >     on adoption etc.
> >
> >     Thanks,
> >     S.
> >     _______________________________________________
> >     CFRG mailing list -- [e-mail]
> >     To unsubscribe send an email to [e-mail]
> >
> >
> >
> > --
> >
> >
> > ORIE STEELEChief Technology Officerwww.transmute.industries
> >
> > <https://transmute.industries>
> >
> >
> > _______________________________________________
> > CFRG mailing list [e-mail]
> > To unsubscribe send an email [e-mail]
> --
> ------------------------------------------------------------------------
>
> Dr. Greg M. Bernstein, https://www.grotto-networking.com
>
>