Development Note
What features are not implemented and why?
Options
SSL_dh_file, SSL_dh, SSL_ecdh_curve
I'm not a security expert so I select the default OpenSSL settings.
verify_hostname
Too complex to implement for now. It is good that another module implements this method.
errstr
Errors are reported by exceptions.
OCSP and SCSP Stapling Features
Too complex to implement for now. It is good that another module implements a callback for OCSP stapling.
Session Features
Too complex to implement for now. It is good that another module implements a callback for SSL session.
Callbacks
Too complex to implement them for now. It is good to use Net::SSLeay object directly.
NPN
Generally, NPN is not recommended.