richardbergquist / ld-signatures-java

Java implementation of Linked Data Signatures

ld-signatures-java

Information

This is an implementation of the following cryptographic suites for Linked Data Proofs:

• Ed25519Signature2018
• Ed25519Signature2020
• EcdsaSecp256k1Signature2019
• RsaSignature2018
• JsonWebSignature2020
• JcsEd25519Signature2020
• JcsEcdsaSecp256k1Signature2019

Maven

Build:

mvn clean install

Dependency:

<repositories>
	<repository>
		<id>danubetech-maven-public</id>
		<url>https://repo.danubetech.com/repository/maven-public/</url>
	</repository>
</repositories>

<dependency>
	<groupId>info.weboftrust</groupId>
	<artifactId>ld-signatures-java</artifactId>
	<version>1.6.0</version>
</dependency>

Example

Example JSON-LD document:

{
	"@context": {
		"schema": "http://schema.org/",
		"name": "schema:name",
		"homepage": "schema:url",
		"image": "schema:image"
	},
	"name": "Manu Sporny",
	"homepage": "https://manu.sporny.org/",
	"image": "https://manu.sporny.org/images/manu.png"
}

Example code:

JsonLDObject jsonLdObject = JsonLDObject.fromJson(new FileReader("input.jsonld"));

byte[] testEd25519PrivateKey = Hex.decodeHex("984b589e121040156838303f107e13150be4a80fc5088ccba0b0bdc9b1d89090de8777a28f8da1a74e7a13090ed974d879bf692d001cddee16e4cc9f84b60580".toCharArray());

Ed25519Signature2018LdSigner signer = new Ed25519Signature2018LdSigner(testEd25519PrivateKey);
signer.setCreated(new Date());
signer.setProofPurpose(LDSecurityKeywords.JSONLD_TERM_ASSERTIONMETHOD);
signer.setVerificationMethod(URI.create("https://example.com/jdoe/keys/1"));
signer.setDomain("example.com");
signer.setNonce("343s$FSFDa-");
LdProof ldProof = signer.sign(jsonLdObject);

System.out.println(jsonLdObject.toJson(true));

Example Linked Data Proof:

{
    "type": "Ed25519Signature2018",
    "created": "2020-10-15T09:42:46Z",
    "domain": "example.com",
    "nonce" : "343s$FSFDa-",
    "proofPurpose": "assertionMethod",
    "verificationMethod": "https://example.com/jdoe/keys/1",
    "jws": "eyJiNjQiOmZhbHNlLCJjcml0IjpbImI2NCJdLCJhbGciOiJFZERTQSJ9..8sFJcDtO_pYLjIkJNKfIOL3IOgm_bpbOqqr8ha0ZDa-e6XorbywVQmFCATNXPqMV10deru-zajF79tVelKo-Bw"
}

About

Danube Tech - https://danubetech.com/

Originally built during Rebooting Web-of-Trust in Paris on April 21st 2017.

This software library is part of a project that has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 871932