This smart contract implements an example on-chain registry for the public part of verifiable credentials (VCs). The contract follows CIS-4: Credential Registry Standard.
The contract keeps track of credentials' public data, allows managing the VC life cycle, and querying VCs data and status. The intended users are issuers of VCs, holders of VCs, revocation authorities, and verifiers.
When initializing a contract, the issuer provides a type and a schema reference for the credentials in the registry. The schema reference points to a JSON document describing the structure of verifiable credentials in the registry (attributes and their types). If the issuer wants to issue verifiable credentials of several types, they can deploy several instances of this contract with different credential types.
- register/remove revocation authority keys;
- register a new credential;
- revoke a credential;
- update the issuer's metadata;
- update the credential metadata;
- update credential schema reference;
- upgrade the contract, set implementors;
- restore (cancel revocation of) a revoked credential.
- revoke a credential by signing a revocation message.
Revocation authorities are some entities chosen by the issuer that have revocation capabilities. Their public keys are registered by the issuer and a revocation authority signs a revocation message with the corresponding private key.
- revoke a credential by signing a revocation message.
- view credential status to verify VC validity;
- view credential data to verify proofs (verifiable presentations) requested from holders.