Credential Revocation Registry

Storing Verifiable Credential on a distributed ledger could lead to privacy violation. However, we can store the status of a Verifiable Credential on-chain, with no private information attached to it. Issuers of a Verifiable Credential have the ability to revoke the credential and provide the reason behind it.

Syntax of Verifiable Credential (VC) ID

The syntax for Verifiable Credential ID is as follows:

vc:hid:<chain-namespace>:<method-specific-id>

• vc:hid - VC Method, where vc is the document identifier and hid is the method name

• <chain-namespace> - (Optional) Name of the blockchain where the VC status is registered. It is omitted for the document registered on mainnet chain

• <method-specific-id> - Alpha-numeric string of minimum 32 character length

VC Status Operations

• Transaction Based

  • Register/Update a VC Status Document

• Query Based

  • Query a VC Status Document

  • Query Registered VC Status Documents

Supported VC Statuses

Following are the VC statuses supported by hid-node:

• Live

• Suspended

• Revoked

• Expired

NOTE: VC Statuses are case sensetive. Live is valid, while live is invalid

Status Change Rules

• Unregistered VC Status Document should only have the status as Live

• Suspended status can be changed to Revoked and Live

• Revoked and Expired statuses cannot be changed

Supported Hash Algorithm

Following are the supported hash algorithms for the attribute credentialHash:

• SHA-256

Register/Update VC Status

Both registeration and update of VC Status happens through the RPC RegisterCredentialStatus.

CLI Signature

Usage:
  hid-noded tx ssi register-credential-status [credential-status] [proof]

Params:
 - credential-status : Credential Status Document
 - proof : Issuer's Signature Format

credential-status Structure

{
    "claim": {
        "id": "vc:hid:<chain-namespace>:z8BXg2zjwBRTrjPs7uCnkFBKrL9bPD14HxEJMENxm3CJ4",
        "currentStatus": "Live",
        "statusReason": "Credential Active"
    },
    "issuer": "did:hid:devnet:zEYJrMxWigf9boyeJMTRN4Ern8DJMoCXaLK77pzQmxVjf",
    "issuanceDate": "2022-04-10T04:07:12Z",
    "expirationDate": "2023-02-22T13:45:55Z",
    "credentialHash": "< -- SHA-256 Hash of VC -->"
}

proof Structure

{
    "type": "Ed25519VerificationKey2020",
    "created": "2022-04-10T04:07:12Z",
    "updated": "2022-04-10T04:07:12Z",
    "verificationMethod": "did:hid:devnet:zEYJrMxWigf9boyeJMTRN4Ern8DJMoCXaLK77pzQmxVjf#key-1",
    "proofValue": "<-- Base64 encoded signature -->",
    "proofPurpose": "assertion"
}

The field proofValue holds the signature that was produced by signing the credential-status document.

Example

hid-noded tx ssi register-credential-status '{"claim":{"id":"vc:hid:<chain-namespace>:z8BXg2zjwBRTrjPs7uCnkFBKrL9bPD14HxEJMENxm3CJ4","currentStatus":"Live","statusReason":"Credential Active"},"issuer":"did:hid:devnet:zEYJrMxWigf9boyeJMTRN4Ern8DJMoCXaLK77pzQmxVjf","issuanceDate":"2022-04-10T04:07:12Z","expirationDate":"2023-02-22T13:45:55Z","credentialHash":"< -- SHA-256 Hash of VC -->"}' '{"type":"Ed25519VerificationKey2020","created":"2022-04-10T04:07:12Z","updated":"2022-04-10T04:07:12Z","verificationMethod":"did:hid:devnet:zEYJrMxWigf9boyeJMTRN4Ern8DJMoCXaLK77pzQmxVjf#key-1","proofValue":"<-- Base64 encoded signature -->","proofPurpose":"assertion"}' --from <hid-account>

Query VC Status

CLI Signature

Usage:
  hid-noded q ssi credential-status [credential-id]

Example

hid-noded q ssi credential-status vc:hid:<chain-namespace>:z8BXg2zjwBRTrjPs7uCnkFBKrL9bPD14HxEJMENxm3CJ4

REST

1. Query credential status for an inpug credential id:

http://<REST-URL>/hypersign-protocol/hidnode/ssi/credential/{credId}

1. Query list of registered credential statuses:

http://<REST-URL>/hypersign-protocol/hidnode/ssi/credential