JWT Token Validator

The JWT Token Validator service allows verifying if a given JWT token is valid.

Usage

The service exposes the GET-/verify endpoint that validates a JWT token. The JWT token is passed to the endpoint inside the header Authorization: Bearer <JWT token>

The endpoint will return:

• if the JWT is valid, its payload,
• an error indicating that the JWT is malformed or is not valid, and why.

Configuration

The service needs to be configured using the Mia-Platform Console. The environment variables needed are:

• JWKS_ENCRYPTION_KEYS_PATH: path to the file containing all the information required to decrypt the JWE.
• ISSUER_CONFIGURATION_PATH: the runtime mount path of the ConfigMap containing the configuration file of the service (e.g. ./configs).
• ISSUER_CONFIGURATION_FILENAME: the file name of the configuration (e.g. ./issuer-config). It must be a json file. Note: remove the file format in the environment variable as the service will append .json at the end.

As described above, the service requires a ConfigMap configuration. The configuration is a json object with a jwtConfig field which is an array of objects. Each object has the following fields:

• JWKSSignatureEndpoint: the endpoint supplied by the issuer that contains the public keys information in JWKS format. They are needed to validate the signature of the JWT token.
• requiredClaims: list of required claims (e.g. aud,iss). It could be an empty string. If a claim is not required, its validation will return true if the value is valid or is unset. These are the claims validated by the service: exp, iat, nbf, aud, iss.
• issuer: the issuer of the JWT
• audience: a string or an array of strings that lists all the audiences. In case the JWT token inside its aud claim has different values from the ones defined in this field, it won't be valid. The aud claim identifies the recipients that the JWT is intended for. This means that the service tells that it's identifying itself with the defined value.
• customGroups: array of strings that allow to set one or more custom groups to a issuer. The values are added to the response of the /verify when the issuer is in the JWT claims. In case the claim groups is already present in the JWT payload, a union of the values is returned.

Given the example below, the service is identifying itself with a dih value for a JWT coming from the issuer issuer-one. Supposing that the JWT has an aud value that does not appear in the audience list, the JWT will be rejected as it is not meant for the service.

Following is an example of the configuration:

{
  "jwtConfig": [
    {
      "JWKSSignatureEndpoint": "https://endpoint-issuer/.well-known/jwks.json",
      "requiredClaims": "aud,iss",
      "issuer": "issuer-one",
      "audience": "dih",
      "customGroups": []
    },
    {
      "JWKSSignatureEndpoint": "https://endpoint-issuer-two/.well-known/jwks.json",
      "requiredClaims": "",
      "issuer": "issuer-two",
      "audience": [
        "dih",
        "another_audience"
      ],
      "customGroups": [
        "groupA",
        "groupB"
      ]
    }
  ]
}

With this configuration, you can support as many issuers as you need for JWT tokens. At the moment, it's only possible to support JWE supplied by a single issuer.