SSL_free() decrements the reference count of ssl, and removes the SSL
structure pointed to by ssl and frees up the allocated memory if the
the reference count has reached 0.
NOTES
SSL_free() also calls the free()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.
RETURN VALUES
SSL_free() does not provide diagnostic information.