ModSecurity Wasm Filter For Istio/Envoy Mesh

This is the source code of the modsecurity-wasm-filter for Istio/Envoy Mesh Http Filter.

We offer a Envoy WASM Plugin integrated with ModSecurity to implement the WAF functionality in the http filter chain. We containerd the WASM binary so users can easily deploy the filter in their istio/envoy mesh.

The plugin is the basic version and the modsecurity rule inside the plugin can be updated by the istio CR WasmPlugin. And we support dynamic update of the wasm binary and modsecurity rules based on istio > 1.13. The rule server for OWASP rules and customer rules will be delivered in the future.

1. Build and upload wasm plugin:

First, clone the repository and open into wasmplugin folder :

git clone 
cd modsecurity-wasm-filter/wasmplugin

Run docker build to build modsecurity wasm plugin. This will generate a docker image containing a single wasm binary.

docker build -t ${HUB}/${IMAGE_NAME}:${TAG} -f Dockerfile .

Run docker push to push the binary to remote repository:

docker push ${HUB}/${IMAGE_NAME}:${TAG}

2. Deploy wasm plugin into istio-ingressgateway http filter chain

Get binding port for http2

kubectl get svc istio-ingressgateway -n istio-system

NAME                   TYPE       CLUSTER-IP    EXTERNAL-IP   PORT(S)                                      AGE
istio-ingressgateway   NodePort   $CLUSTER-IP   <none>        15021:31164/TCP,80:30829/TCP,443:30501/TCP   28d

The output here shows that the istio-ingressgateway service is forwarding requests from port 80 to port 30829

Update /rule-service/rule-service.yaml to make sure the nodeport value of the service be the same with the istio-ingressgateway forwarding nodeport value.

Enable automatic proxy sidecar injection:

kubectl label namespaces default istio-injection=enabled

Create config map from custom modsecurity.conf

kubectl create cm rule-configmap --from-file=index.html= rule-example/modsecurity.conf

Create rule-service

kubectl apply -f rule-service/rule-service.yaml

Enable wasmplugin

kubectl apply -f istio/mod-wasm-deploy.yaml

3. Test modsecurity wasm plugin with istio-ingressgateway

Set up ingress ports:

export INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?("http2")].nodePort}')

export SECURE_INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?("https")].nodePort}')

export TCP_INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?("tcp")].nodePort}')

export INGRESS_HOST=$(kubectl get po -l istio=ingressgateway -n istio-system -o jsonpath='{.items[0].status.hostIP}')

Create an ingress gateway for the service:

kubectl apply -f - <<EOF
kind: Gateway
  name: mygateway
    istio: ingressgateway # use Istio default gateway implementation
  - port:
      number: 80
      name: http
      protocol: HTTP
    - ""

Create a virtual service for the ingress gateway:

kubectl apply -f - <<EOF
kind: VirtualService
  name: nginx
  - ""
  - mygateway
  - match:
    - uri:
        prefix: /
    - destination:
          number: 80
        host: testapp

To confirm the ingress gateway is working properly, using the following command:

This should return HTTP 200 OK:

curl -v http://$INGRESS_HOST:$INGRESS_PORT?param1=test

This should return HTTP 404 Not Found:

curl -v http://$INGRESS_HOST:$INGRESS_PORT?param1=attack


View Github