Semaphore Inclusion Proof

Once a user has added their identity commitment to either the credentials or no-credentials group, they can use Semaphore proofs to signal anonymously with a zero-knowledge proof that proves that:

• they are part of the credentials/no-credentials group, and

• the same user created the signal and the proof

Generating a proof

Similar to a Semaphore proof, you can use the @bq-core/lib library to generate such proofs, passing the following parameters to the generateCredentialOwnershipProof function:

• identity: the Semaphore identity of the user broadcasting the signal and generating the proof.

• groupOrMerkleProof: the group to which the user belongs, either the credentials or no-credentials group, or the corresponding Merkle proof.

• externalNullifier: the value that prevents double-signaling.

• signal: the signal the user wants to send anonymously.

• snarkArtifacts: the zkey and wasm trusted setup files, taken from PSE SNARK artifacts

Verifying a Proof Off-Chain

You can use the @bq-core/lib library to verify a generated proof via the verifyCredentialOwnershipProof function:

import { verifyCredentialOwnershipProof } from "@bq-core/lib"

await verifyCredentialOwnershipProof(testProof) // true or false.

Which returns a promise that resolves to true or false.