OpenSSL provides multiple SSL objects to be created from a single SSL_CTX object and each SSL object can use a different privatekey file (SSL_use_PrivateKey_file).
Given this flexibility, I don't see an option to have a password callback function per SSL object. The callbacks are provided only on the SSL_CTX object. Is there a work around to this other than creating an SSL_CTX object for every privatekey file that needs to be added in the application. Thanks, Karthik