OpenSSL SSL_CTX_sess_set_get_cb(3openssl)
NNNNAAAAMMMMEEEESSL_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 -
provide callback functions for server side external session caching SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS#include
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); DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNNSSL_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 function
pointers of the provided callback functions. If a callback function has not been set, the NULL pointer is returned. NNNNOOOOTTTTEEEESSSS In order to allow external session caching, synchronization with the internal session cache is realized via callback27/Mar/2003 Last change: 0.9.8o 1
OpenSSL SSL_CTX_sess_set_get_cb(3openssl)
functions. Inside these callback functions, session can be saved to disk or put into a database using thed2i_SSL_SESSION(3) interface.
The new_session_cb() is called, whenever a new session has
been negotiated and session caching is enabled (seeSSL_CTX_set_session_cache_mode(3)). The new_session_cb() is
passed the ssssssssllll connection and the ssl session sssseeeessssssss. If the callback returns 0000, 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 when the session is removed because it is expired or when a connection was not shutdown cleanly. It also happens for allsessions in the internal session cache when SSL_CTX_free(3)
is called. The remove_session_cb() is passed the ccccttttxxxx and the
ssl session sssseeeessssssss. 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_session_cb()
is always called, also when session caching was disabled.The get_session_cb() is passed the ssssssssllll connection, the
session id of length lllleeeennnnggggtttthhhh at the memory location ddddaaaattttaaaa. With the parameter ccccooooppppyyyy the callback can require the SSLengine 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 withSSL_SESSION_free(3).
SSSSEEEEEEEE AAAALLLLSSSSOOOOssl(3), d2i_SSL_SESSION(3),
SSL_CTX_set_session_cache_mode(3),
SSL_CTX_flush_sessions(3), SSL_SESSION_free(3),
SSL_CTX_free(3)
27/Mar/2003 Last change: 0.9.8o 2