Data Integrity library _(@digitalbazaar/data-integrity)_


> DataIntegrity library for use with cryptosuites and jsonld-signatures.

Table of Contents

- Background
- Security
- Install
- Usage
- Contribute
- Commercial Support
- License

Background

For use with https://github.com/digitalbazaar/jsonld-signatures v11.0 and above.

See also related specs:

* Verifiable Credential Data Integrity

Security

TBD

Install

- Browsers and Node.js 18+ are supported.

To install from NPM:

``
npm install @digitalbazaar/data-integrity
`

To install locally (for development):

`
git clone https://github.com/digitalbazaar/data-integrity.git
cd data-integrity
npm install
`

Usage

The following code snippet provides a complete example of digitally signing
a verifiable credential using this library:

`javascript
import * as Ed25519Multikey from '@digitalbazaar/ed25519-multikey';
import {DataIntegrityProof} from '@digitalbazaar/data-integrity';
import {cryptosuite as eddsa2022CryptoSuite} from
'@digitalbazaar/eddsa-2022-cryptosuite';
import jsigs from 'jsonld-signatures';
const {purposes: {AssertionProofPurpose}} = jsigs;


// create the unsigned credential
const unsignedCredential = {
'@context': [
'https://www.w3.org/2018/credentials/v1',
{
AlumniCredential: 'https://schema.org#AlumniCredential',
alumniOf: 'https://schema.org#alumniOf'
}
],
id: 'http://example.edu/credentials/1872',
type: [ 'VerifiableCredential', 'AlumniCredential' ],
issuer: 'https://example.edu/issuers/565049',
issuanceDate: '2010-01-01T19:23:24Z',
credentialSubject: {
id: 'https://example.edu/students/alice',
alumniOf: 'Example University'
}
};

// create the keypair to use when signing
const controller = 'https://example.edu/issuers/565049';
const keyPair = await Ed25519Multikey.from({
'@context': 'https://w3id.org/security/multikey/v1',
type: 'Multikey',
controller,
id: controller + '#z6MkwXG2WjeQnNxSoynSGYU8V9j3QzP3JSqhdmkHc6SaVWoT',
publicKeyMultibase: 'z6MkwXG2WjeQnNxSoynSGYU8V9j3QzP3JSqhdmkHc6SaVWoT',
secretKeyMultibase: 'zrv3rbPamVDGvrm7LkYPLWYJ35P9audujKKsWn3x29EUiGwwhdZQd' +
'1iHhrsmZidtVALBQmhX3j9E5Fvx6Kr29DPt6LH'
});

// export public key and add to document loader
const publicKey = await keyPair.export({publicKey: true, includeContext: true});
addDocumentToLoader({url: publicKey.id, document: publicKey});

// create key's controller document
const controllerDoc = {
'@context': [
'https://www.w3.org/ns/did/v1',
'https://w3id.org/security/multikey/v1'
],
id: controller,
assertionMethod: [publicKey]
};
addDocumentToLoader({url: controllerDoc.id, document: controllerDoc});

// create suite
const suite = new DataIntegrityProof({
signer: keyPair.signer(), cryptosuite: eddsa2022CryptoSuite
});

// create signed credential
const signedCredential = await jsigs.sign(unsignedCredential, {
suite,
purpose: new AssertionProofPurpose(),
documentLoader
});

// results in the following signed VC
{
"@context": [
"https://www.w3.org/2018/credentials/v1",
{
"AlumniCredential": "https://schema.org#AlumniCredential",
"alumniOf": "https://schema.org#alumniOf"
},
"https://w3id.org/security/data-integrity/v2"
],
"id": "http://example.edu/credentials/1872",
"type": [
"VerifiableCredential",
"AlumniCredential"
],
"issuer": "https://example.edu/issuers/565049",
"issuanceDate": "2010-01-01T19:23:24Z",
"credentialSubject": {
"id": "https://example.edu/students/alice",
"alumniOf": "Example University"
},
"proof": {
"type": "DataIntegrityProof",
"created": "2022-09-06T21:29:24Z",
"verificationMethod": "https://example.edu/issuers/565049#z6MkwXG2WjeQnNxSoynSGYU8V9j3QzP3JSqhdmkHc6SaVWoT",
"cryptosuite": "eddsa-2022",
"proofPurpose": "assertionMethod",
"proofValue": "zakT6XP6P7ZVAGJKjvnVi1YjC96RufyeasEEMkDQrCkvMnG3QeAqBuoVoWAWkEEd5w8FATEigPA5788ByuwnCZrd"
}
}
`

Note: To create or verify proofs using legacy draft data integrity suites, you
must pass legacyContext: true when creating a DataIntegrityProof` instance;
this will cause the appropriate legacy data integrity context (
https://w3id.org/security/data-integrity/v1) to be used.

Contribute

See the contribute file!

PRs accepted.

If editing the Readme, please conform to the
standard-readme specification.

Commercial Support

Commercial support for this library is available upon request from
Digital Bazaar: support@digitalbazaar.com

License

New BSD License (3-clause) © 2022 Digital Bazaar