NAME

       SSL_set_num_tickets, SSL_get_num_tickets, SSL_CTX_set_num_tickets, SSL_CTX_get_num_tickets
       - control the number of TLSv1.3 session tickets that are issued

SYNOPSIS

        #include <openssl/ssl.h>

        int SSL_set_num_tickets(SSL *s, size_t num_tickets);
        size_t SSL_get_num_tickets(SSL *s);
        int SSL_CTX_set_num_tickets(SSL_CTX *ctx, size_t num_tickets);
        size_t SSL_CTX_get_num_tickets(SSL_CTX *ctx);

DESCRIPTION

       SSL_CTX_set_num_tickets() and SSL_set_num_tickets() can be called for a server application
       and set the number of session tickets that will be sent to the client after a full
       handshake. Set the desired value (which could be 0) in the num_tickets argument. Typically
       these functions should be called before the start of the handshake.

       The default number of tickets is 2; the default number of tickets sent following a
       resumption handshake is 1 but this cannot be changed using these functions.  The number of
       tickets following a resumption handshake can be reduced to 0 using custom session ticket
       callbacks (see SSL_CTX_set_session_ticket_cb(3)).

       Tickets are also issued on receipt of a post-handshake certificate from the client
       following a request by the server using SSL_verify_client_post_handshake(3). These new
       tickets will be associated with the updated client identity (i.e. including their
       certificate and verification status). The number of tickets issued will normally be the
       same as was used for the initial handshake. If the initial handshake was a full handshake
       then SSL_set_num_tickets() can be called again prior to calling
       SSL_verify_client_post_handshake() to update the number of tickets that will be sent.

       SSL_CTX_get_num_tickets() and SSL_get_num_tickets() return the number of tickets set by a
       previous call to SSL_CTX_set_num_tickets() or SSL_set_num_tickets(), or 2 if no such call
       has been made.

RETURN VALUES

       SSL_CTX_set_num_tickets() and SSL_set_num_tickets() return 1 on success or 0 on failure.

       SSL_CTX_get_num_tickets() and SSL_get_num_tickets() return the number of tickets that have
       been previously set.

HISTORY

       These functions were added in OpenSSL 1.1.1.

COPYRIGHT

       Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (the "License").  You may not use this file except in
       compliance with the License.  You can obtain a copy in the file LICENSE in the source
       distribution or at <https://www.openssl.org/source/license.html>.