JWT claim based routing

    Note: this feature only supports Istio ingress gateway and requires the use of both request authentication and virtual service to properly validate and route based on JWT claims.

    The following information describes an experimental feature, which is intended for evaluation purposes only.

    • Understand Istio and virtual service concepts.

    • Install Istio using the .

    • Deploy a workload, in a namespace, for example foo, and expose it through the Istio ingress gateway with this command:

      Zip

    • Follow the instructions in Determining the ingress IP and ports to define the INGRESS_HOST and INGRESS_PORT environment variables.

      1. $ curl "$INGRESS_HOST:$INGRESS_PORT"/headers -s -o /dev/null -w "%{http_code}\n"
      2. 200

    If you don’t see the expected output, retry after a few seconds. Caching and propagation overhead can cause a delay.

    The Istio ingress gateway supports routing based on authenticated JWT, which is useful for routing based on end user identity and more secure compared using the unauthenticated HTTP attributes (e.g. path or header).

    1. In order to route based on JWT claims, first create the request authentication to enable JWT validation:

      1. $ kubectl apply -f - <<EOF
      2. apiVersion: security.istio.io/v1beta1
      3. kind: RequestAuthentication
      4. metadata:
      5.   name: ingress-jwt
      6.   namespace: istio-system
      7. spec:
      8.   selector:
      9.     matchLabels:
      10.       istio: ingressgateway
      11.   - issuer: "testing@secure.istio.io"
      12.     jwksUri: "https://raw.githubusercontent.com/istio/istio/release-1.15/security/tools/jwt/samples/jwks.json"
      13. EOF

      The request authentication enables JWT validation on the Istio ingress gateway so that the validated JWT claims can later be used in the virtual service for routing purposes.

      The request authentication is applied on the ingress gateway because the JWT claim based routing is only supported on ingress gateways.

      Note: the request authentication will only check the JWT if it exists in the request. To make the JWT required and reject the request if it does not include JWT, apply the authorization policy as specified in the task.

    2. Update the virtual service to route based on validated JWT claims:

      1. $ kubectl apply -f - <<EOF
      2. apiVersion: networking.istio.io/v1alpha3
      4. metadata:
      5.   name: httpbin
      6.   namespace: foo
      7. spec:
      8.   hosts:
      9.   - "*"
      10.   gateways:
      11.   - httpbin-gateway
      12.   http:
      13.   - match:
      14.     - uri:
      15.         prefix: /headers
      16.       headers:
      17.         "@request.auth.claims.groups":
      18.           exact: group1
      19.     - destination:
      20.         port:
      21.           number: 8000
      22.         host: httpbin
      23. EOF

      Claim of type string, list of string and nested claims are supported. Use the . as a separator for nested claim names. For example, "@request.auth.claims.name.givenName" matches the nested claim name and givenName. Claim name with the . character is currently not supported.

    1. Validate the ingress gateway returns the HTTP code 404 without JWT:

      You can also create the authorization policy to explicitly reject the request with HTTP code 403 when JWT is missing.

    2. Validate the ingress gateway returns the HTTP code 401 with invalid JWT:

      1. $ curl -s -I "http://$INGRESS_HOST:$INGRESS_PORT/headers" -H "Authorization: Bearer some.invalid.token"
      2. HTTP/1.1 401 Unauthorized
      3. ...

      The 401 is returned by the request authentication because the JWT failed the validation.

    3. Validate the ingress gateway routes the request with a valid JWT token that includes the claim groups: group1:

      1. $ TOKEN_GROUP=$(curl https://raw.githubusercontent.com/istio/istio/release-1.15/security/tools/jwt/samples/groups-scope.jwt -s) && echo "$TOKEN_GROUP" | cut -d '.' -f2 - | base64 --decode -
      2. {"exp":3537391104,"groups":["group1","group2"],"iat":1537391104,"iss":"testing@secure.istio.io","scope":["scope1","scope2"],"sub":"testing@secure.istio.io"}
      1. $ curl -s -I "http://$INGRESS_HOST:$INGRESS_PORT/headers" -H "Authorization: Bearer $TOKEN_GROUP"
      2. HTTP/1.1 200 OK
      3. ...

    4. Validate the ingress gateway returns the HTTP code 404 with a valid JWT but does not include the claim groups: group1:

      1. $ curl -s -I "http://$INGRESS_HOST:$INGRESS_PORT/headers" -H "Authorization: Bearer $TOKEN_NO_GROUP"
      2. HTTP/1.1 404 Not Found
      3. ...
      1. $ kubectl delete namespace foo