====== Certificates ====== ===== Client Testing ===== [[https://badssl.com/|badssl.com]] offers a lot of links to subdomains with different tls configurations. This is helful to test how clients behave in certain situations. Here some examples. user@laptop:~$ curl https://self-signed.badssl.com/ curl: (60) SSL certificate problem: self-signed certificate More details here: https://curl.se/docs/sslcerts.html curl failed to verify the legitimacy of the server and therefore could not establish a secure connection to it. To learn more about this situation and how to fix it, please visit the web page mentioned above. user@laptop:~$ curl https://expired.badssl.com/ curl: (60) SSL certificate problem: certificate has expired More details here: https://curl.se/docs/sslcerts.html curl failed to verify the legitimacy of the server and therefore could not establish a secure connection to it. To learn more about this situation and how to fix it, please visit the web page mentioned above. user@laptop:~$ curl https://dh480.badssl.com/ curl: (35) error:0280007E:Diffie-Hellman routines::modulus too small