ring-jwt

Ring middleware for parsing, decoding and verifying a JWS-signed JWT token from the incoming request.

Built on top of the excellent auth0 JWT library.

Once wired into to your ring server, the middleware will:

• Search for a JWT token on each incoming request (see below for information on where it looks).
• Will add the claims it finds in the token as a clojure map against the :claims key on the incoming request.
• Add an empty :claims map to the request if no token is found.
• Respond with a 401 if the JWS signature in the token cannot be verified.
• Respond with a 401 if the token has expired (i.e. the exp claim indicates a time in the past)
• Respond with a 401 if the token will only be active in the future (i.e. the nbf claim indicates a time in the future)

Note that there is the option to specify a leeway for the exp/nbf checks - see usage below.

Installation

[ovotech/ring-jwt "1.2.0"]

Usage

(require '[ring.middleware.jwt :as jwt])

(defn handler [request]
  (response {:foo "bar"}))

(jwt/wrap-jwt handler {:alg    :HS256
                       :secret "yoursecret"})

Depending upon the cryptographic algorithm that is selected for the middleware, a different map of options will be required. Note that, at the point your ring middleware is wired up, ring-jwt will throw an error if it detects that the given options are invalid.

Currently the following JWA algorithms are supported for the purposes of JWS:

Algorithm	Options
ECDSA using P-256 and SHA-256	{:alg :ES256 :public-key public-key}
RSASSA-PKCS-v1_5 using SHA-256	{:alg :RS256 :public-key public-key} [1]
	{:alg :RS256 :jwk-endpoint "https://your/jwk/endpoint"}
HMAC using SHA-256	{:alg :HS256 :secret "your-secret"}

[1] public-key is of type java.security.PublicKey.

Additionally, the following optional options are supported:

• leeway-seconds: The number of seconds leeway to give when verifying the expiry/active from claims of the token (i.e. the exp and nbf claims).
• issuer: The issuer of the token, if this does not match the issuer on a token a 401 will be returned.
• find-token-fn: The single-argument function that will be used to pull the (encoded) token from the request map.

If a find-token-fn function is not specified in the options the default behaviour is to look for the token as the bearer token given in the Authorization header (i.e. an Authorization HTTP header of the form "Bearer TOKEN")

Useful links

• JSON Web Tokens - JWT Specification
• JSON Web Signatures - JWS Specification
• JSON Web Algorithms - JWA Specification
• JSON Web Keys - JWK Specification
• jwt.io

License

Copyright © 2018 Ovo Energy Ltd.

Distributed under the Eclipse Public License, the same as Clojure.