Someone

$SERVER["socket"] == "0.0.0.0:443" {
  ssl.engine                  = "enable"
  ssl.pemfile                 = "server.pem"
}
else $HTTP["host"] =~ "(^|\.)domain\.net$" {
  url.redirect = (
       "^/(.*)" => "https://%1.domain.net/$1",
       ""       => "https://%1.domain.net/"
  )
}