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DID Method Specification

did:jwk is a deterministic transformation of a JWK into a DID Document.

DID Format

did-jwk-format   := did:jwk:<base64url-value>
base64url-value  := [A-Za-z0-9_-]+

The base64url-value is a base64url encoded JSON Web Key (JWK).

DID Operations

Create

To create the DID:

  1. Generate or load a JWK
  2. Serialize it into a UTF-8 string
  3. Encode that string using base64url
  4. Attach the prefix did:jwk:

Canonicalization such as JCS is not required but may be helpful if the resulting DID isn't going to be stored in its serialized form.

To create the DID Document:

The JWK is used to generate the DID Document. The resulting document will take the form below with the base64url encoded value described above replacing ${base64url-value}, and the JSON Web Key structure replacing ${json-web-key}:

{
  "@context": [
    "https://www.w3.org/ns/did/v1",
    "https://w3id.org/security/suites/jws-2020/v1"
  ],
  "id": "did:jwk:${base64url-value}",
  "verificationMethod": [
    {
      "id": "did:jwk:${base64url-value}#0",
      "type": "JsonWebKey2020",
      "controller": "did:jwk:${base64url-value}",
      "publicKeyJwk": ${json-web-key}
    }
  ],
  "assertionMethod": ["did:jwk:${base64url-value}#0"],
  "authentication": ["did:jwk:${base64url-value}#0"],
  "capabilityInvocation": ["did:jwk:${base64url-value}#0"],
  "capabilityDelegation": ["did:jwk:${base64url-value}#0"],
  "keyAgreement": ["did:jwk:${base64url-value}#0"]
}

If the JWK contains a use property with the value "sig" then the keyAgreement property is not included in the DID Document. If the use value is "enc" then only the keyAgreement property is included in the DID Document.

The JWK should have the appropriate use value set to match the capabilities of the specified crv. For example, the curve ed25519 is only valid for "sig" use and X25519 is only valid for "enc" (see RFC 8037 and the second example below).

The JWK may contain additional custom properties and values which will be accessible only in the verificationMethod. Any additional properties other than use (as documented above) are not referenced or used in the generation of the DID Document.

To create the DID URL:

Since did:jwk only contains a single key, the DID URL fragment identifier is always a fixed #0 value.

If the JWK contains a kid value it is not used as the reference, #0 is the only valid value.

Read

  1. Remove the prefix did:jwk:
  2. Decode the remaining string using base64url
  3. Parse the decoded string as UTF-8 JSON
  4. Validate the JWK properties
  5. Generate a DID Document using the contained public key material as defined above in

Update

Not supported.

Deactivate

Not supported.

Examples

P-256

DID

did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9

DID URL

did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9#0

DID Document

{
  "@context": [
    "https://www.w3.org/ns/did/v1",
    "https://w3id.org/security/suites/jws-2020/v1"
  ],
  "id": "did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9",
  "verificationMethod": [
    {
      "id": "did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9#0",
      "type": "JsonWebKey2020",
      "controller": "did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9",
      "publicKeyJwk": {
        "crv": "P-256",
        "kty": "EC",
        "x": "acbIQiuMs3i8_uszEjJ2tpTtRM4EU3yz91PH6CdH2V0",
        "y": "_KcyLj9vWMptnmKtm46GqDz8wf74I5LKgrl2GzH3nSE"
      }
    }
  ],
  "assertionMethod": ["did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9#0"],
  "authentication": ["did:jwk:$eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9#0"],
  "capabilityInvocation": ["did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9#0"],
  "capabilityDelegation": ["did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9#0"],
  "keyAgreement": ["did:jwk:eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6ImFjYklRaXVNczNpOF91c3pFakoydHBUdFJNNEVVM3l6OTFQSDZDZEgyVjAiLCJ5IjoiX0tjeUxqOXZXTXB0bm1LdG00NkdxRHo4d2Y3NEk1TEtncmwyR3pIM25TRSJ9#0"]
}

X25519

DID

did:jwk:eyJrdHkiOiJPS1AiLCJjcnYiOiJYMjU1MTkiLCJ1c2UiOiJlbmMiLCJ4IjoiM3A3YmZYdDl3YlRUVzJIQzdPUTFOei1EUThoYmVHZE5yZngtRkctSUswOCJ9

DID URL

did:jwk:eyJrdHkiOiJPS1AiLCJjcnYiOiJYMjU1MTkiLCJ1c2UiOiJlbmMiLCJ4IjoiM3A3YmZYdDl3YlRUVzJIQzdPUTFOei1EUThoYmVHZE5yZngtRkctSUswOCJ9#0

DID Document

{
  "@context": [
    "https://www.w3.org/ns/did/v1",
    "https://w3id.org/security/suites/jws-2020/v1"
  ],
  "id": "did:jwk:eyJrdHkiOiJPS1AiLCJjcnYiOiJYMjU1MTkiLCJ1c2UiOiJlbmMiLCJ4IjoiM3A3YmZYdDl3YlRUVzJIQzdPUTFOei1EUThoYmVHZE5yZngtRkctSUswOCJ9",
  "verificationMethod": [
    {
      "id": "did:jwk:eyJrdHkiOiJPS1AiLCJjcnYiOiJYMjU1MTkiLCJ1c2UiOiJlbmMiLCJ4IjoiM3A3YmZYdDl3YlRUVzJIQzdPUTFOei1EUThoYmVHZE5yZngtRkctSUswOCJ9#0",
      "type": "JsonWebKey2020",
      "controller": "did:jwk:eyJrdHkiOiJPS1AiLCJjcnYiOiJYMjU1MTkiLCJ1c2UiOiJlbmMiLCJ4IjoiM3A3YmZYdDl3YlRUVzJIQzdPUTFOei1EUThoYmVHZE5yZngtRkctSUswOCJ9",
      "publicKeyJwk": {
        "kty":"OKP",
        "crv":"X25519",
        "use":"enc",
        "x":"3p7bfXt9wbTTW2HC7OQ1Nz-DQ8hbeGdNrfx-FG-IK08"
      }
    }
  ],
  "keyAgreement": ["did:jwk:eyJrdHkiOiJPS1AiLCJjcnYiOiJYMjU1MTkiLCJ1c2UiOiJlbmMiLCJ4IjoiM3A3YmZYdDl3YlRUVzJIQzdPUTFOei1EUThoYmVHZE5yZngtRkctSUswOCJ9#0"]
}

Security and Privacy Considerations

Since this JWK method is very similar to the DID Key method, see also did-key

Security

Only JWKs containing public key material may be used, a JWK for a private key must never be used and must be rejected by all implementations when encountered.

Since the key material is part of the identifier there is no support for key rotation, if the key is compromised then the identifier becomes unusable and unrecoverable.

This method does not provide any guarantees of a 1:1 relationship between the identifier and the public key. The same public key can result in many different identifiers due to variances in how the JWK JSON is serialized. This is a design choice, implementations should always store the fully serialized did:jwk: URI and not the underlying JWK.

There is no provided means of cryptographically verifying possession of the public key material, any such verification must be performed separately by applications using a sufficient challenge-response protocol.

Privacy

Using the same DID JWK identifier with multiple different entities will enable those entities to correlate the usage to the same subject.