NAME

       SSL_SESSION_free - free an allocated SSL_SESSION structure

SYNOPSIS

        #include <openssl/ssl.h>

        void SSL_SESSION_free(SSL_SESSION *session);

DESCRIPTION

       SSL_SESSION_free() decrements the reference count of session and removes the SSL_SESSION
       structure pointed to by session and frees up the allocated memory, if the reference count
       has reached 0.

NOTES

       SSL_SESSION objects are allocated, when a TLS/SSL handshake operation is successfully
       completed. Depending on the settings, see SSL_CTX_set_session_cache_mode(3), the
       SSL_SESSION objects are internally referenced by the SSL_CTX and linked into its session
       cache. SSL objects may be using the SSL_SESSION object; as a session may be reused,
       several SSL objects may be using one SSL_SESSION object at the same time. It is therefore
       crucial to keep the reference count (usage information) correct and not delete a
       SSL_SESSION object that is still used, as this may lead to program failures due to
       dangling pointers. These failures may also appear delayed, e.g.  when an SSL_SESSION
       object was completely freed as the reference count incorrectly became 0, but it is still
       referenced in the internal session cache and the cache list is processed during a
       SSL_CTX_flush_sessions(3) operation.

       SSL_SESSION_free() must only be called for SSL_SESSION objects, for which the reference
       count was explicitly incremented (e.g.  by calling SSL_get1_session(), see
       SSL_get_session(3)) or when the SSL_SESSION object was generated outside a TLS handshake
       operation, e.g. by using d2i_SSL_SESSION(3).  It must not be called on other SSL_SESSION
       objects, as this would cause incorrect reference counts and therefore program failures.

RETURN VALUES

       SSL_SESSION_free() does not provide diagnostic information.

SEE ALSO

       ssl(3), SSL_get_session(3), SSL_CTX_set_session_cache_mode(3), SSL_CTX_flush_sessions(3),
        d2i_SSL_SESSION(3)