#include <openssl/ssl.h> int SSL_set_session(SSL *ssl, SSL_SESSION *session);
SSL_set_session() sets session to be used when the TLS/SSL connection is to be established. SSL_set_session() is only useful for TLS/SSL clients. When the session is set, the reference count of session is incremented by 1. If the session is not reused, the reference count is decremented again during SSL_connect(). Whether the session was reused can be queried with the SSL_session_reused(3) call.
If there is already a session set inside ssl (because it was set with SSL_set_session() before or because the same ssl was already used for a connection), SSL_SESSION_free() will be called for that session. This is also the case when session is a NULL pointer. If that old session is still open, it is considered bad and will be removed from the session cache (if used). A session is considered open, if SSL_shutdown(3) was not called for the connection (or at least SSL_set_shutdown(3) was used to set the SSL_SENT_SHUTDOWN state).
SSL_SESSION objects keep internal link information about the session cache list, when being inserted into one SSL_CTX object's session cache. One SSL_SESSION object, regardless of its reference count, must therefore only be used with one SSL_CTX object (and the SSL objects created from this SSL_CTX object).
The following return values can occur:
The operation failed; check the error stack to find out the reason.
The operation succeeded.
ssl(7), SSL_SESSION_free(3), SSL_get_session(3), SSL_session_reused(3), SSL_CTX_set_session_cache_mode(3)
Copyright 2000-2022 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (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>.
SSL_clear.3ossl(3), SSL_CTX_sess_number.3ossl(3), SSL_CTX_set_session_cache_mode.3ossl(3), SSL_CTX_set_tlsext_ticket_key_cb.3ossl(3), SSL_session_reused.3ossl(3).