SSL_CTX_sess_set_get_cb(3) - NetBSD Manual Pages

SSL_CTX_sess_set_get_cb(3)   OpenSSL   SSL_CTX_sess_set_get_cb(3)



NAME

       SSL_CTX_sess_set_new_cb, SSL_CTX_sess_set_remove_cb,
       SSL_CTX_sess_set_get_cb, SSL_CTX_sess_get_new_cb,
       SSL_CTX_sess_get_remove_cb, SSL_CTX_sess_get_get_cb - pro-
       vide callback functions for server side external session
       caching


LIBRARY

       libcrypto, -lcrypto


SYNOPSIS

        #include <openssl/ssl.h>

        void SSL_CTX_sess_set_new_cb(SSL_CTX *ctx,
                                     int (*new_session_cb)(SSL *, SSL_SESSION *));
        void SSL_CTX_sess_set_remove_cb(SSL_CTX *ctx,
                  void (*remove_session_cb)(SSL_CTX *ctx, SSL_SESSION *));
        void SSL_CTX_sess_set_get_cb(SSL_CTX *ctx,
                  SSL_SESSION (*get_session_cb)(SSL *, unsigned char *, int, int *));

        int (*SSL_CTX_sess_get_new_cb(SSL_CTX *ctx))(struct ssl_st *ssl, SSL_SESSION *sess);
        void (*SSL_CTX_sess_get_remove_cb(SSL_CTX *ctx))(struct ssl_ctx_st *ctx, SSL_SESSION *sess);
        SSL_SESSION *(*SSL_CTX_sess_get_get_cb(SSL_CTX *ctx))(struct ssl_st *ssl, unsigned char *data, int len, int *copy);

        int (*new_session_cb)(struct ssl_st *ssl, SSL_SESSION *sess);
        void (*remove_session_cb)(struct ssl_ctx_st *ctx, SSL_SESSION *sess);
        SSL_SESSION *(*get_session_cb)(struct ssl_st *ssl, unsigned char *data,
                      int len, int *copy);



DESCRIPTION

       SSL_CTX_sess_set_new_cb() sets the callback function,
       which is automatically called whenever a new session was
       negotiated.

       SSL_CTX_sess_set_remove_cb() sets the callback function,
       which is automatically called whenever a session is
       removed by the SSL engine, because it is considered faulty
       or the session has become obsolete because of exceeding
       the timeout value.

       SSL_CTX_sess_set_get_cb() sets the callback function which
       is called, whenever a SSL/TLS client proposed to resume a
       session but the session could not be found in the internal
       session cache (see SSL_CTX_set_session_cache_mode(3)).
       (SSL/TLS server only.)

       SSL_CTX_sess_get_new_cb(), SSL_CTX_sess_get_remove_cb(),
       and SSL_CTX_sess_get_get_cb() allow to retrieve the func-
       tion pointers of the provided callback functions. If a
       callback function has not been set, the NULL pointer is
       returned.





2002-07-31                    0.9.6g                            1





SSL_CTX_sess_set_get_cb(3)   OpenSSL   SSL_CTX_sess_set_get_cb(3)



NOTES

       In order to allow external session caching, synchroniza-
       tion with the internal session cache is realized via call-
       back functions. Inside these callback functions, session
       can be saved to disk or put into a database using the
       d2i_SSL_SESSION(3) interface.

       The new_session_cb() is called, whenever a new session has
       been negotiated and session caching is enabled (see
       SSL_CTX_set_session_cache_mode(3)).  The new_session_cb()
       is passed the ssl connection and the ssl session sess. If
       the callback returns 0, the session will be immediately
       removed again.

       The remove_session_cb() is called, whenever the SSL engine
       removes a session from the internal cache. This happens if
       the session is removed because it is expired or when a
       connection was not shutdown cleanly. The remove_ses-
       sion_cb() is passed the ctx and the ssl session sess.  It
       does not provide any feedback.

       The get_session_cb() is only called on SSL/TLS servers
       with the session id proposed by the client. The get_ses-
       sion_cb() is always called, also when session caching was
       disabled. The get_session_cb() is passed the ssl connec-
       tion, the session id of length length at the memory loca-
       tion data. With the parameter copy the callback can
       require the SSL engine to increment the reference count of
       the SSL_SESSION object, Normally the reference count is
       not incremented and therefore the session must not be
       explicitly freed with SSL_SESSION_free(3).


SEE ALSO

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





















2002-07-31                    0.9.6g                            2