A simple tcpdump sidecar injector to demonstrate Kubernetes's Mutating Webhook

Build docker image;

docker build -t bilalunalnet/tcpdump-webhook .

Generate private key and certificate for SSL connection.

openssl req -new -sha256 \
     -newkey rsa:2048 \
     -subj "/C=TR/ST=Istanbul/O=tcpdump-webhook/CN=tcpdump-webhook.webhook-demo.svc" \
     -nodes -x509 \
     -days 365 \
     -out server.crt \
     -addext "subjectAltName = DNS:tcpdump-webhook.webhook-demo.svc"

Update ConfigMap data in the manifest/webhook-deployment.yaml file with your key and certificate.

Update caBundle value in the manifest/webhook-configuration.yaml file with your base64 encoded certificate.

cat server.crt | base64 -w0

kubectl create ns webhook-demo
kubectl apply -f manifest/webhook-deployment.yaml
kubectl apply -f manifest/webhook-configuration.yaml

There is a Pod manifest file in the manifest directory to be used for testing purposes. The Pod has tcpdump-sidecar label to meet the condition in the app/mutator.py file.