1.\" $OpenBSD: SSL_free.3,v 1.6 2021/06/11 19:41:39 jmc 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) 2000, 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: June 11 2021 $ 52.Dt SSL_FREE 3 53.Os 54.Sh NAME 55.Nm SSL_free 56.Nd free an allocated SSL structure 57.Sh SYNOPSIS 58.In openssl/ssl.h 59.Ft void 60.Fn SSL_free "SSL *ssl" 61.Sh DESCRIPTION 62.Fn SSL_free 63decrements the reference count of 64.Fa ssl , 65and removes the 66.Vt SSL 67structure pointed to by 68.Fa ssl 69and frees up the allocated memory if the reference count has reached 0. 70If 71.Fa ssl 72is a 73.Dv NULL 74pointer, no action occurs. 75.Pp 76.Fn SSL_free 77also calls the 78.Xr free 3 Ns 79ing procedures for indirectly affected items, if applicable: the buffering 80.Vt BIO , 81the read and write 82.Vt BIOs , 83cipher lists specially created for this 84.Fa ssl , 85the 86.Sy SSL_SESSION . 87Do not explicitly free these indirectly freed up items before or after calling 88.Fn SSL_free , 89as trying to free things twice may lead to program failure. 90.Pp 91The 92.Fa ssl 93session has reference counts from two users: the 94.Vt SSL 95object, for which the reference count is removed by 96.Fn SSL_free 97and the internal session cache. 98If the session is considered bad, because 99.Xr SSL_shutdown 3 100was not called for the connection and 101.Xr SSL_set_shutdown 3 102was not used to set the 103.Vt SSL_SENT_SHUTDOWN 104state, the session will also be removed from the session cache as required by 105RFC 2246. 106.Sh SEE ALSO 107.Xr ssl 3 , 108.Xr SSL_clear 3 , 109.Xr SSL_new 3 , 110.Xr SSL_set_shutdown 3 , 111.Xr SSL_shutdown 3 112.Sh HISTORY 113.Fn SSL_free 114appeared in SSLeay 0.4 or earlier and has been available since 115.Ox 2.4 . 116