did-jwt

The did-JWT library allows you to sign and verify JSON Web Tokens (JWT)
using ES256K and EdDSA algorithms. The non-standard ES256K-R is also supported for backward compatibility
reasons, as well as the Ed25519 legacy name for EdDSA.

Public keys are resolved using the Decentralized ID (DID) of the signing
identity of the token, which is passed as the iss attribute of the JWT payload.

DID methods

All DID methods that can be resolved using the did-resolver
interface are supported for verification.

If your DID method requires a different signing algorithm than what is already supported, please create an issue.

Installation

``bash
npm install did-jwt
`

or if you use yarn

`bash
yarn add did-jwt
`

Example

$3

In practice, you must secure the key passed to ES256KSigner. The key provided in code below is for informational
purposes only.

`ts
import didJWT from 'did-jwt';

const signer = didJWT.ES256KSigner(didJWT.hexToBytes('278a5de700e29faae8e40e366ec5012b5ec63d36ec77e8a2417154cc1d25383f'))

let jwt = await didJWT.createJWT(
{ aud: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74', iat: undefined, name: 'uPort Developer' },
{ issuer: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74', signer },
{ alg: 'ES256K' }
)
console.log(jwt)
`

$3

Try decoding the JWT. You can also do this using jwt.io

`js
//pass the jwt from step 1
let decoded = didJWT.decodeJWT(jwt)
console.log(decoded)
`

Once decoded a did-JWT will resemble:

`ts
expect(decoded).toEqual({
header: { alg: 'ES256K', typ: 'JWT' },
payload: {
aud: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74',
name: 'uPort Developer',
iss: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74'
},
signature: 'mAhpAnw-9u57hyAaDufj2GPMbmuZyPDlU7aYSUMKk7P_9_cF3iLk-hFjFhb5xaUQB5nXYrciw6ZJ2RSAZI-IDQ',
data: 'eyJhbGciOiJFUzI1NksiLCJ0eXAiOiJKV1QifQ.eyJhdWQiOiJkaWQ6ZXRocjoweGYzYmVhYzMwYzQ5OGQ5ZTI2ODY1ZjM0ZmNhYTU3ZGJiOTM1YjBkNzQiLCJuYW1lIjoidVBvcnQgRGV2ZWxvcGVyIiwiaXNzIjoiZGlkOmV0aHI6MHhmM2JlYWMzMGM0OThkOWUyNjg2NWYzNGZjYWE1N2RiYjkzNWIwZDc0In0'
})
`

$3

You need to provide a did-resolver for the verify function. For this example we will use did:ethr, but there are other
methods available. For more information on configuring the Resolver object please
see did-resolver

`bash
npm install ethr-did-resolver
`

`js
import {Resolver} from 'did-resolver';
import {getResolver} from 'ethr-did-resolver'

let resolver = new Resolver({...getResolver({infuraProjectId: ''})});

// use the JWT from step 1
let verificationResponse = await didJWT.verifyJWT(jwt, {
resolver,
audience: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74'
})
console.log(verificationResponse)
`

A verification response is an object resembling:

`typescript
expect(verificationResponse).toEqual({
payload: {
aud: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74',
name: 'uPort Developer',
iss: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74'
},
didResolutionResult: {
didDocumentMetadata: {},
didResolutionMetadata: { contentType: 'application/did+ld+json' },
didDocument: {
'@context': [
'https://www.w3.org/ns/did/v1',
'https://w3id.org/security/suites/secp256k1recovery-2020/v2'
],
id: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74',
verificationMethod: [
{
id: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74#controller',
type: 'EcdsaSecp256k1RecoveryMethod2020',
controller: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74',
blockchainAccountId: 'eip155:1:0xF3beAC30C498D9E26865F34fCAa57dBB935b0D74'
}
],
authentication: [
'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74#controller'
],
assertionMethod: [
'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74#controller'
]
}
},
issuer: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74',
signer: {
id: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74#controller',
type: 'EcdsaSecp256k1RecoveryMethod2020',
controller: 'did:ethr:0xf3beac30c498d9e26865f34fcaa57dbb935b0d74',
blockchainAccountId: 'eip155:1:0xF3beAC30C498D9E26865F34fCAa57dBB935b0D74'
},
jwt: 'eyJhbGciOiJFUzI1NksiLCJ0eXAiOiJKV1QifQ.eyJhdWQiOiJkaWQ6ZXRocjoweGYzYmVhYzMwYzQ5OGQ5ZTI2ODY1ZjM0ZmNhYTU3ZGJiOTM1YjBkNzQiLCJuYW1lIjoidVBvcnQgRGV2ZWxvcGVyIiwiaXNzIjoiZGlkOmV0aHI6MHhmM2JlYWMzMGM0OThkOWUyNjg2NWYzNGZjYWE1N2RiYjkzNWIwZDc0In0.mAhpAnw-9u57hyAaDufj2GPMbmuZyPDlU7aYSUMKk7P_9_cF3iLk-hFjFhb5xaUQB5nXYrciw6ZJ2RSAZI-IDQ',
policies: {}
})
``