1.\" $OpenBSD: SSL_get_ex_data_X509_STORE_CTX_idx.3,v 1.5 2022/02/06 00:29:02 jsg Exp $ 2.\" OpenSSL 9b86974e Aug 17 15:21:33 2015 -0400 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: February 6 2022 $ 52.Dt SSL_GET_EX_DATA_X509_STORE_CTX_IDX 3 53.Os 54.Sh NAME 55.Nm SSL_get_ex_data_X509_STORE_CTX_idx 56.Nd get ex_data index to access SSL structure from X509_STORE_CTX 57.Sh SYNOPSIS 58.In openssl/ssl.h 59.Ft int 60.Fn SSL_get_ex_data_X509_STORE_CTX_idx void 61.Sh DESCRIPTION 62.Fn SSL_get_ex_data_X509_STORE_CTX_idx 63returns the index number under which the pointer to the 64.Vt SSL 65object is stored into the 66.Vt X509_STORE_CTX 67object. 68.Pp 69Whenever a 70.Vt X509_STORE_CTX 71object is created for the verification of the peer's certificate during a 72handshake, a pointer to the 73.Vt SSL 74object is stored into the 75.Vt X509_STORE_CTX 76object to identify the connection affected. 77To retrieve this pointer the 78.Xr X509_STORE_CTX_get_ex_data 3 79function can be used with the correct index. 80This index is globally the same for all 81.Vt X509_STORE_CTX 82objects and can be retrieved using 83.Fn SSL_get_ex_data_X509_STORE_CTX_idx . 84The index value is set when 85.Fn SSL_get_ex_data_X509_STORE_CTX_idx 86is first called either by the application program directly or indirectly during 87other SSL setup functions or during the handshake. 88.Pp 89The value depends on other index values defined for 90.Vt X509_STORE_CTX 91objects before the SSL index is created. 92.Sh RETURN VALUES 93.Bl -tag -width Ds 94.It \(>=0 95The index value to access the pointer. 96.It <0 97An error occurred, check the error stack for a detailed error message. 98.El 99.Sh EXAMPLES 100The index returned from 101.Fn SSL_get_ex_data_X509_STORE_CTX_idx 102provides access to 103.Vt SSL 104object for the connection during the 105.Fn verify_callback 106when checking the peer's certificate. 107Check the example in 108.Xr SSL_CTX_set_verify 3 . 109.Sh SEE ALSO 110.Xr CRYPTO_set_ex_data 3 , 111.Xr ssl 3 , 112.Xr SSL_CTX_set_verify 3 113.Sh HISTORY 114.Fn SSL_get_ex_data_X509_STORE_CTX_idx 115first appeared in SSLeay 0.9.1 and has been available since 116.Ox 2.6 . 117