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
npm install did-jwt
or if you use yarn
yarn add did-jwt
Example
1. Create a did-JWT
In practice, you must secure the key passed to ES256KSigner
. The key provided in code below is for informational
purposes only.
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)
2. Decode a did-JWT
Try decoding the JWT. You can also do this using jwt.io
//pass the jwt from step 1
let decoded = didJWT.decodeJWT(jwt)
console.log(decoded)
Once decoded a did-JWT will resemble:
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. Verify a did-JWT
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
npm install ethr-did-resolver
import {Resolver} from 'did-resolver';
import {getResolver} from 'ethr-did-resolver'
let resolver = new Resolver({...getResolver({infuraProjectId: '<get a free ID from infura.io>'})});
// 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:
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: {}
})