map "" $empty {
    default "";
}

server {
    listen 80 default_server;
    listen [::]:80 default_server;

    listen 443 ssl default_server;
    listen [::]:443 ssl default_server;
    http2 on;

    server_name _;

    ssl_ciphers aNULL;
    ssl_certificate /etc/nginx/ssl/dummy.cert;
    ssl_certificate_key /etc/nginx/ssl/dummy.key;

    return 444;
}