testssl.sh
Testing TLS/SSL encryption anywhere on any port
... to be postinstalled. You can test any SSL/TLS enabled and STARTTLS service, not only webservers at port 443. Several command line options help you to run your test and configure your output. If a particular check cannot be performed because of a missing capability on your client side, you'll get a warning. You can look at the code, see what's going on and you can change it.