NAME
SSL_get_session
,
SSL_get0_session
,
SSL_get1_session
—
retrieve TLS/SSL session
data
SYNOPSIS
#include
<openssl/ssl.h>
SSL_SESSION *
SSL_get_session
(const
SSL *ssl);
SSL_SESSION *
SSL_get0_session
(const
SSL *ssl);
SSL_SESSION *
SSL_get1_session
(SSL
*ssl);
DESCRIPTION
SSL_get_session
()
returns a pointer to the SSL_SESSION actually used in
ssl. The reference count of the
SSL_SESSION is not incremented, so that the pointer
can become invalid by other operations.
SSL_get0_session
()
is the same as SSL_get_session
().
SSL_get1_session
()
is the same as SSL_get_session
(), but the reference
count of the SSL_SESSION is incremented by one.
The ssl session contains all information required to re-establish the connection without a new handshake.
SSL_get0_session
()
returns a pointer to the actual session. As the reference counter is not
incremented, the pointer is only valid while the connection is in use. If
SSL_clear(3) or
SSL_free(3) is called,
the session may be removed completely (if considered bad), and the pointer
obtained will become invalid. Even if the session is valid, it can be
removed at any time due to timeout during
SSL_CTX_flush_sessions(3).
If the data is to be kept,
SSL_get1_session
()
will increment the reference count, so that the session will not be
implicitly removed by other operations but stays in memory. In order to
remove the session, SSL_SESSION_free(3) must be explicitly called once to decrement the
reference count again.
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).
RETURN VALUES
The following return values can occur:
NULL
- There is no session available in ssl.
- Pointer to an SSL_SESSION
- The return value points to the data of an SSL session.
SEE ALSO
ssl(3), SSL_clear(3), SSL_free(3), SSL_SESSION_free(3), SSL_SESSION_get0_peer(3), SSL_SESSION_get_compress_id(3), SSL_SESSION_get_id(3), SSL_SESSION_get_protocol_version(3), SSL_SESSION_get_time(3), SSL_SESSION_new(3), SSL_SESSION_print(3), SSL_set_session(3)
HISTORY
SSL_get_session
() first appeared in SSLeay
0.5.2 and has been available since OpenBSD 2.4.
SSL_get0_session
() and
SSL_get1_session
() first appeared in OpenSSL 0.9.5
and have been available since OpenBSD 2.7.