free an allocated SSL structure
SSL structure pointed to by ssl and frees up the allocated memory if the reference count has reached 0.
free(3)ing procedures for indirectly affected items, if applicable: the buffering BIO, the read and write BIOs, cipher lists specially created for this ssl, the SSL_SESSION. Do not explicitly free these indirectly freed up items before or after calling SSL_free(), as trying to free things twice may lead to program failure.The ssl session has reference counts from two users: the SSL object, for which the reference count is removed by SSL_free() and the internal session cache. If the session is considered bad, because SSL_shutdown(3) was not called for the connection and SSL_set_shutdown(3) was not used to set the SSL_SENT_SHUTDOWN state, the session will also be removed from the session cache as required by RFC2246.