Edit me

Claim and Attestation

Version 1.0.0

English / 中文

Verifiable claim

Data structure specification

class Claim{
  header : Header
  payload : Payload
  signature : byte[]
}

class Header {
    public String Alg = "ONT-ES256";
    public String Typ = "JWT-X";
    public String Kid;
    }

alg attribute specifies the signature scheme to use typ attribute can take one of the two values:

* JWT: This corresponds to the case that blockchain proof is not contained in the claim
* JWT-X: This corresponds to the case that blockchain proof is a part of the claim

kid attribute refers to the public key used for signature verification. It has the form #keys- as defined in ONT ID specification.

class Payload {
    public String Ver;
    public String Iss;
    public String Sub;
    public long Iat;
    public long Exp;
    public String Jti;
    @JSONField(name = "@context")
    public String Context;
    public Map<String, Object> ClmMap = new HashMap<String, Object>();
    public Map<String, Object> ClmRevMap = new HashMap<String, Object>();
    }

ver attribute specifies the version of the claim specification it follows

iss attribute refers to the ONT ID of the issuer

sub attribute refers to the ONT ID of the recipient

iat attribute marks the time the claim was created and has the unix timestamp format

exp attribute marks the expiration time of the claim and has the the unix timestamp format

jti attribute specifies the unique identifier of the verifiable claim

@context attribute specifies the uri of the claim content definition document which defines the meaning of each field and the type of the value

clm attribute is an object which contains the claim content

clm-rev attribute is an object which defines the revocation mechanism the claim uses <p>

Sign and issue verifiable claim

A verifiable claim is constructed based on user input, which contains signed data.

createOntIdClaim

Parameter	Field	Type	Description	Remarks
Input parameter	signerOntid	String	ONT ID	Required
	password	String	ONT ID password	Required
	salt	byte[]	Private key decryption parameters	Required
	context	String	Attribute specifies the URI of claim content definition document which defines the meaning of each field and the type of the value	Required
	claimMap	Map	Content of claim	Required
	metaData	Map	Claim issuer and subject’s ONT ID	Required
	clmRevMap	Map	Attribute is an object which defines the revocation mechanism the claim use	Required
	expire	long	Attribute marks the expiration time of the claim and has the format of unix timestamp	required
Output parameter	claim	String

Refer to: https://github.com/kunxian-xia/ontology-DID/blob/master/docs/en/claim_spec.md

Example of creating an onit claim

String createOntIdClaim (String signerOntid, String password,byte[] salt, String context, Map<String, Object> claimMap, Map metaData,Map clmRevMap,long expire)

Map<String, Object> map = new HashMap<String, Object>();
map.put("Issuer", dids.get(0).ontid);
map.put("Subject", dids.get(1).ontid);
Map clmRevMap = new HashMap();
clmRevMap.put("typ","AttestContract");
clmRevMap.put("addr",dids.get(1).ontid.replace(Common.didont,""));
String claim = ontSdk.nativevm().ontId().createOntIdClaim(dids.get(0).ontid,password,salt, "claim:context", map, map,clmRevMap,System.currentTimeMillis()/1000 +100000);

Note: The issuer may have multiple public keys. The parameter ontid of createOntIdClaim specifies which public key to use. <p>

Verify verifiable claim

verifyOntIdClaim

Parameter	Field	Type	Description	Remarks
Input parameter	claim	String	Trusted claim	Required
Output parameter	true or false	boolean

boolean verifyOntIdClaim (string claim)

Example of verifying an ontid claim

boolean b = ontSdk.nativevm().ontId().verifyOntIdClaim(claim);

Example of claim issuance and verification:

Map<String, Object> map = new HashMap<String, Object>();
map.put("Issuer", dids.get(0).ontid);
map.put("Subject", dids.get(1).ontid);

Map clmRevMap = new HashMap();
clmRevMap.put("typ","AttestContract");
clmRevMap.put("addr",dids.get(1).ontid.replace(Common.didont,""));

String claim = ontSdk.nativevm().ontId().createOntIdClaim(dids.get(0).ontid,password,salt, "claim:context", map, map,clmRevMap,System.currentTimeMillis()/1000 +100000);
boolean b = ontSdk.nativevm().ontId().verifyOntIdClaim(claim);

Attestation Example

The attest contract of a verifiable claim provides the attest service and records availability information, that is, whether it has been revoked.

SDK init

String ip = "http://127.0.0.1";
String restUrl = ip + ":" + "20334";
String rpcUrl = ip + ":" + "20336";
String wsUrl = ip + ":" + "20335";
OntSdk wm = OntSdk.getInstance();
wm.setRpc(rpcUrl);
wm.setRestful(restUrl);
wm.setDefaultConnect(wm.getRestful());
wm.openWalletFile("RecordTxDemo.json");

Note: codeAddress is the address of the record contract.

Create claim

Map<String, Object> map = new HashMap<String, Object>();
map.put("Issuer", dids.get(0).ontid);
map.put("Subject", dids.get(1).ontid);

Map clmRevMap = new HashMap();
clmRevMap.put("typ","AttestContract");
clmRevMap.put("addr",dids.get(1).ontid.replace(Common.didont,""));

String claim = ontSdk.nativevm().ontId().createOntIdClaim(dids.get(0).ontid,password,dids.get(0).controls.get(0).getSalt(), "claim:context", map, map,
clmRevMap,System.currentTimeMillis()/1000 +100000);

Note: For createOntIdClaim interface details please see the digital identity ontid document https://github.com/ontio/ontology-java-sdk/blob/master/docs/cn/identity_claim.md

The specification of the following interface document is: https://github.com/kunxian-xia/ontology-DID/blob/master/docs/en/claim_spec.md.

Storage Claim

sendCommit

String sendCommit (String issuerOntid, String password,byte[] salt, String subjectOntid, String claimId, Account payerAcct, long gaslimit, long gasprice)

Function description: Save data to the chain

Parameters: issuerOntid: Issuer ONT ID subjectOntid: Subject ONT ID password: Identity password claimId: Trusted claims claim uniqueness mark, i.e. Jti field in Claim payerAcct: Payment transaction account gaslimit: Gas limit gasprice: Gas price return value: Transaction hash

Example

String[] claims = claim.split("\\.");
JSONObject payload = JSONObject.parseObject(new String(Base64.getDecoder().decode(claims[1].getBytes())));
ontSdk.neovm().claimRecord().sendCommit(ontid,password,payload.getString("jti"),0)

Get Status

sendGetStatus

 String sendGetStatus(String claimId)

Function description: Query status of trusted claim

Parameters: claimId: Trusted claims claim uniqueness mark, i.e. Jti field in Claim

return value： Part 1: Status of the claim: “Not attested”, “Attested”, “Attest has been revoked” Part 2: The certificate’s ONT ID.

Example

String getstatusRes2 = ontSdk.neovm().claimRecord().sendGetStatus(payload.getString("jti"));

Revoke

sendRevoke

String sendRevoke(String issuerOntid,String password,byte[] salt,String claimId,Account payerAcct,long gaslimit,long gas)

Function description:Repeal of a trust claim

Parameters: issuerOntid: Issuer ONT ID password: Attester’s ONT ID password claimId: Trusted claims claim uniqueness mark, i.e. Jti field in Claim payerAcct: Payment transaction account gaslimit: Gas limit gasprice: Gas price

return value： This function will return true if and only if the claim is attested, and the revokerOntId is equal to the attester’s ONT identity; Otherwise, it will return false.