certX

certX

This represents the publicly available blockchain storage for decentralised credentials. There are two modules:

1. credentials - this provides publicly available plaintext credential for verification. This is used to demonstrate use case 1
2. eCredentials - this provides publicly available encrypted credential (use case 2)

credentials module

The credential module executes the following upon receiving an IBC message:

1. receives IBC messages from Issuer Zones containing verifiable credentials
2. verify the signature of the message as the actual issuer
3. records the credential

credential types and packets

# Stores all credentials that were received via IBC
# note the original holder is not provided, only the new did
Credential: {
    # Verifier this proof is meant to be for, e.g. restaurant
    verifier: did
    # Issuer of the claim, e.g. Health Authority
    issuer: did,
    # Subject the claim is about, e.g. Alice's one time unique
    subject:did,
    # Actual claim, e.g. vaccination record received
    claim: Int 
}

# Packet received via IBC
verifiableCredential {
    # Verifier this proof is meant to be for, e.g. restaurant
    verifier: did,
    # Issuer of this proof, e.g. health authority
    issuer: did 
    # The identifier for the verifier, e.g. Alice's new did created for the restaurant
    subject: did,
    # Actual claim, e.g. vaccination record received or simply fully / partial / none
    # (i.e. the issuer can obfuscate details if they see fit)
    claim: some_claim_description,
    # Signature of the Issuer and related metadata
    # i.e. public key and signature for verification
    signature: signature_info 
}

eCredential module

The eCredential module executes the following upon receiving an IBC message:

1. simply receives the credential and stores it.

eCredential CLI

When querying for a specific eCredential, a user can provide the shared key (from the holder), and the CLI will display the credential in plain text.

If no key provided, then only encrypted text will be returned.

certXd query eCredentials show-eCredentialRecord <claim-id> <shared-key>

eCredential types

eCredential / eCredentialRecord {
    # Subject did, e.g. Alice's did created when applying for a role
    subject: did,
    # Encrypted text of the credential, i.e. alice's employment history
    claim: string
}

Useful Commands

# Query new plaintext credential from 
certXd query credentials list-credential --node tcp://localhost:36657

# Query specific encrypted credential with shared key
# If no key is provided, cipher text of credential is returned 
certXd query eCredentials show-eCredentialRecord <id> <shared key> --node tcp://localhost:36657