.\"	$OpenBSD: SSL_set_session.3,v 1.4 2018/03/27 17:35:50 schwarze Exp $
.\"	OpenSSL 05ea606a May 20 20:52:46 2016 -0400
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.Dd $Mdocdate: March 27 2018 $
.Dt SSL_SET_SESSION 3
.Os
.Sh NAME
.Nm SSL_set_session
.Nd set a TLS/SSL session to be used during TLS/SSL connect
.Sh SYNOPSIS
.In openssl/ssl.h
.Ft int
.Fn SSL_set_session "SSL *ssl" "SSL_SESSION *session"
.Sh DESCRIPTION
.Fn SSL_set_session
sets
.Fa session
to be used when the TLS/SSL connection is to be established.
.Fn SSL_set_session
is only useful for TLS/SSL clients.
When the session is set, the reference count of
.Fa session
is incremented
by 1.
If the session is not reused, the reference count is decremented again during
.Fn SSL_connect .
Whether the session was reused can be queried with the
.Xr SSL_session_reused 3
call.
.Pp
If there is already a session set inside
.Fa ssl
(because it was set with
.Fn SSL_set_session
before or because the same
.Fa ssl
was already used for a connection),
.Xr SSL_SESSION_free 3
will be called for that session.
.Pp
.Vt SSL_SESSION
objects keep internal link information about the session cache list when being
inserted into one
.Vt SSL_CTX
object's session cache.
One
.Vt SSL_SESSION
object, regardless of its reference count, must therefore only be used with one
.Vt SSL_CTX
object (and the
.Vt SSL
objects created from this
.Vt SSL_CTX
object).
.Sh RETURN VALUES
The following return values can occur:
.Bl -tag -width Ds
.It 0
The operation failed; check the error stack to find out the reason.
.It 1
The operation succeeded.
.El
.Sh SEE ALSO
.Xr ssl 3 ,
.Xr SSL_CTX_set_session_cache_mode 3 ,
.Xr SSL_get_session 3 ,
.Xr SSL_SESSION_free 3 ,
.Xr SSL_session_reused 3
.Sh HISTORY
.Fn SSL_set_session
first appeared in SSLeay 0.5.2 and has been available since
.Ox 2.4 .