Generate an SSL certificate for a KASM instance. Requires Certbot & Docker to be installed.

kasm_cert.sh

#!/usr/bin/env bash

# Leverages Docker containers to create a temporary signing server
# Obtain a SSL cert and then apply it to the service in question we're interested in

# Usage: ./kasm_cert.sh mydomain.test

mkdir -p /tmp/webroot

# Start an ephemeral nginx container
docker run --rm --name temp-nginx -v /tmp/webroot/:/usr/share/nginx/html -p 80:80 -d nginx

# Get the certificate
sudo certbot certonly --webroot -w /tmp/webroot -d $1 -n

# Backup existing Certs
sudo cp /opt/kasm/current/certs/kasm_nginx.crt /tmp/kasm_nginx.backup.crt
sudo cp /opt/kasm/current/certs/kasm_nginx.key /tmp/kasm_nginx.backup.key

# Copy the certificates
sudo cp /etc/letsencrypt/live/$1/fullchain.pem /opt/kasm/current/certs/kasm_nginx.crt
sudo cp /etc/letsencrypt/live/$1/privkey.pem /opt/kasm/current/certs/kasm_nginx.key

# restart Kasm
sudo /opt/kasm/bin/stop
sudo /opt/kasm/bin/start

# Clean up the container
docker stop temp-nginx