Signing RGB consignments

[dr-orlovsky]

We deliberately excluded signatures from RGB genesis as a part of the consensus layer. However, on the level of the standard library, I think the signatures has to be present.

My understanding is that all consignment types should allow signatures to be optionally attached to any of a contract operation item, like genesis, state transition or extension. This will allow issuers to sign genesis and all secondary issuance transitions. The signatures would not participate consensus or consignment validation, but the node should report the wallet if the consignment issue data were signed and were the signatures valid - as well as provide keys for identities which made signatures.

This is why it is not the consignment as a whole which should be signed, but a specific operations (not even bundles) - i.e. the signature should be made over their NodeId.

Node should report the list of signed ids for each processed consignment, like

$ rgb consignment info --interface rgb20

giving output of

invalid_signatures:
    - id: <key_data>
      type: secp256k1
      protocol: RGB22 # or GPG
      nodeIds: [ ] # List of signed node IDs
signatures:
    - id: <key_data>
      type: secp256k1
      protocol: RGB22 # or GPG
      nodeIds: [ ] # List of signed node IDs

[cryptoquick]

Why not use Schnorr signature aggregation for combining the signatures from each individual node_id?

[cryptoquick]

Nevermind, I just looked into it, this is not a thing. Key aggregation is a thing, but that doesn't apply in this context. Sorry, still learning.

[dr-orlovsky]

Sigs are not necessary over Secp256k1, it could be Edwards25519. In the first case we will use Schnorrs, but need to support ECDSA for PGP compatibility. In the second case Schnorr sigs cant be applied to Curve25519 and a sigs over a twisted curve called Ed25519 are needed.

Secp25519 Schnorr sigs can be aggregated during validation for speeding up. Otherwise aggregating sigs in consignment will require complex interactive protocols between all signers (like MuSig) and will not solve any problem.