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5.4.37 mysql_get_ssl_session_data()

void * 
mysql_get_ssl_session_data(MYSQL *, 
                           unsigned int n_ticket, 
                           unsigned int *out_len)


mysql_get_ssl_session_data() permits SSL session reuse by extracting a ticket from an established session and submitting that ticket when connecting, provided the server still has the session in its runtime cache. This function returns a session data string and provides the length of the string in out_len (if non-NULL). Otherwise, it returns nullptr to indicate the expected session data is not possible or the connection is not in the right state. To prevent leaks, you must release the session data handle by calling mysql_free_ssl_session_data() when your application is finished with the pointer.

The format of the data is PEM serialization of the session. A session can be reused only if it was fetched from a prior session to the same mysqld server on the same port. In addition, the SSL version of the new session must match the SSL version of the original session.

n_ticket specifies which ticket or tickets to returned. For TLS 1.3, the server generates two session tickets by default for new sessions and one when a session is reused. For TLS 1.2, the server generates one session ticket by default. This should be considered when deciding on the size of the SSL session cache on the server.


Currently, only the last transmitted session is returned. Specifically, anything other than 0 for n_ticket causes an error. OpenSSL version 1.0.2 imposes this limitation.

Avoid reusing SSL sessions more than one time.

Return Values