1.\" $OpenBSD: SSL_CTX_set_timeout.3,v 1.4 2018/03/27 17:35:50 schwarze Exp $ 2.\" OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100 3.\" 4.\" This file was written by Lutz Jaenicke <jaenicke@openssl.org>. 5.\" Copyright (c) 2001 The OpenSSL Project. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in 16.\" the documentation and/or other materials provided with the 17.\" distribution. 18.\" 19.\" 3. All advertising materials mentioning features or use of this 20.\" software must display the following acknowledgment: 21.\" "This product includes software developed by the OpenSSL Project 22.\" for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 23.\" 24.\" 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 25.\" endorse or promote products derived from this software without 26.\" prior written permission. For written permission, please contact 27.\" openssl-core@openssl.org. 28.\" 29.\" 5. Products derived from this software may not be called "OpenSSL" 30.\" nor may "OpenSSL" appear in their names without prior written 31.\" permission of the OpenSSL Project. 32.\" 33.\" 6. Redistributions of any form whatsoever must retain the following 34.\" acknowledgment: 35.\" "This product includes software developed by the OpenSSL Project 36.\" for use in the OpenSSL Toolkit (http://www.openssl.org/)" 37.\" 38.\" THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 39.\" EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 40.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 41.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 42.\" ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 43.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 44.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 45.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 46.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 47.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 48.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 49.\" OF THE POSSIBILITY OF SUCH DAMAGE. 50.\" 51.Dd $Mdocdate: March 27 2018 $ 52.Dt SSL_CTX_SET_TIMEOUT 3 53.Os 54.Sh NAME 55.Nm SSL_CTX_set_timeout , 56.Nm SSL_CTX_get_timeout 57.Nd manipulate timeout values for session caching 58.Sh SYNOPSIS 59.In openssl/ssl.h 60.Ft long 61.Fn SSL_CTX_set_timeout "SSL_CTX *ctx" "long t" 62.Ft long 63.Fn SSL_CTX_get_timeout "SSL_CTX *ctx" 64.Sh DESCRIPTION 65.Fn SSL_CTX_set_timeout 66sets the timeout for newly created sessions for 67.Fa ctx 68to 69.Fa t . 70The timeout value 71.Fa t 72must be given in seconds. 73.Pp 74.Fn SSL_CTX_get_timeout 75returns the currently set timeout value for 76.Fa ctx . 77.Pp 78Whenever a new session is created, it is assigned a maximum lifetime. 79This lifetime is specified by storing the creation time of the session and the 80timeout value valid at this time. 81If the actual time is later than creation time plus timeout, 82the session is not reused. 83.Pp 84Due to this realization, all sessions behave according to the timeout value 85valid at the time of the session negotiation. 86Changes of the timeout value do not affect already established sessions. 87.Pp 88The expiration time of a single session can be modified using the 89.Xr SSL_SESSION_get_time 3 90family of functions. 91.Pp 92Expired sessions are removed from the internal session cache, whenever 93.Xr SSL_CTX_flush_sessions 3 94is called, either directly by the application or automatically (see 95.Xr SSL_CTX_set_session_cache_mode 3 ) . 96.Pp 97The default value for session timeout is decided on a per-protocol basis; see 98.Xr SSL_get_default_timeout 3 . 99All currently supported protocols have the same default timeout value of 300 100seconds. 101.Sh RETURN VALUES 102.Fn SSL_CTX_set_timeout 103returns the previously set timeout value. 104.Pp 105.Fn SSL_CTX_get_timeout 106returns the currently set timeout value. 107.Sh SEE ALSO 108.Xr ssl 3 , 109.Xr SSL_CTX_flush_sessions 3 , 110.Xr SSL_CTX_set_session_cache_mode 3 , 111.Xr SSL_get_default_timeout 3 , 112.Xr SSL_SESSION_get_time 3 113.Sh HISTORY 114.Fn SSL_CTX_set_timeout 115and 116.Fn SSL_CTX_get_timeout 117first appeared in SSLeay 0.6.1 and have been available since 118.Ox 2.4 . 119