path: root/src/lib/libssl/man/SSL_CTX_add_extra_chain_cert.3

.\" $OpenBSD: SSL_CTX_add_extra_chain_cert.3,v 1.8 2025/01/18 10:45:12 tb Exp $
.\" full merge up to: OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100
.\"
.\" This file was written by Lutz Jaenicke <jaenicke@openssl.org> and
.\" Dr. Stephen Henson <steve@openssl.org>.
.\" Copyright (c) 2000, 2002, 2013, 2015 The OpenSSL Project.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\"
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\"
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in
.\"    the documentation and/or other materials provided with the
.\"    distribution.
.\"
.\" 3. All advertising materials mentioning features or use of this
.\"    software must display the following acknowledgment:
.\"    "This product includes software developed by the OpenSSL Project
.\"    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
.\"
.\" 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
.\"    endorse or promote products derived from this software without
.\"    prior written permission. For written permission, please contact
.\"    openssl-core@openssl.org.
.\"
.\" 5. Products derived from this software may not be called "OpenSSL"
.\"    nor may "OpenSSL" appear in their names without prior written
.\"    permission of the OpenSSL Project.
.\"
.\" 6. Redistributions of any form whatsoever must retain the following
.\"    acknowledgment:
.\"    "This product includes software developed by the OpenSSL Project
.\"    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
.\" EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
.\" ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
.\" OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd $Mdocdate: January 18 2025 $
.Dt SSL_CTX_ADD_EXTRA_CHAIN_CERT 3
.Os
.Sh NAME
.Nm SSL_CTX_add_extra_chain_cert ,
.Nm SSL_CTX_get_extra_chain_certs_only ,
.Nm SSL_CTX_get_extra_chain_certs ,
.Nm SSL_CTX_clear_extra_chain_certs
.Nd add, retrieve, and clear extra chain certificates
.Sh SYNOPSIS
.In openssl/ssl.h
.Ft long
.Fn SSL_CTX_add_extra_chain_cert "SSL_CTX *ctx" "X509 *x509"
.Ft long
.Fn SSL_CTX_get_extra_chain_certs_only "SSL_CTX *ctx" "STACK_OF(X509) **certs"
.Ft long
.Fn SSL_CTX_get_extra_chain_certs "SSL_CTX *ctx" "STACK_OF(X509) **certs"
.Ft long
.Fn SSL_CTX_clear_extra_chain_certs "SSL_CTX *ctx"
.Sh DESCRIPTION
.Fn SSL_CTX_add_extra_chain_cert
adds the certificate
.Fa x509
to the extra chain certificates associated with
.Fa ctx .
Several certificates can be added one after another.
.Pp
.Fn SSL_CTX_get_extra_chain_certs_only
retrieves an internal pointer to the stack of extra chain certificates
associated with
.Fa ctx ,
or set
.Pf * Fa certs
to
.Dv NULL
if there are none.
.Pp
.Fn SSL_CTX_get_extra_chain_certs
does the same except that it retrieves an internal pointer
to the chain associated with the certificate
if there are no extra chain certificates.
.Pp
.Fn SSL_CTX_clear_extra_chain_certs
clears all extra chain certificates associated with
.Fa ctx .
.Pp
These functions are implemented as macros.
.Pp
When sending a certificate chain, extra chain certificates are sent
in order following the end entity certificate.
.Pp
If no chain is specified, the library will try to complete the chain from the
available CA certificates in the trusted CA storage, see
.Xr SSL_CTX_load_verify_locations 3 .
.Pp
The x509 certificate provided to
.Fn SSL_CTX_add_extra_chain_cert
will be freed by the library when the
.Vt SSL_CTX
is destroyed.
An application should not free the
.Fa x509
object, nor the
.Pf * Fa certs
object retrieved by
.Fn SSL_CTX_get_extra_chain_certs .
.Sh RETURN VALUES
These functions return 1 on success or 0 for failure.
Check out the error stack to find out the reason for failure.
.Sh SEE ALSO
.Xr ssl 3 ,
.Xr SSL_CTX_add1_chain_cert 3 ,
.Xr SSL_CTX_ctrl 3 ,
.Xr SSL_CTX_load_verify_locations 3 ,
.Xr SSL_CTX_set_client_cert_cb 3 ,
.Xr SSL_CTX_use_certificate 3
.Sh HISTORY
.Fn SSL_CTX_add_extra_chain_cert
first appeared in SSLeay 0.9.1 and has been available since
.Ox 2.6 .
.Pp
.Fn SSL_CTX_get_extra_chain_certs
and
.Fn SSL_CTX_clear_extra_chain_certs
first appeared in OpenSSL 1.0.1 and have been available since
.Ox 5.3 .
.Pp
.Fn SSL_CTX_get_extra_chain_certs_only
first appeared in OpenSSL 1.0.2 and has been available since
.Ox 6.7 .
.Sh CAVEATS
Certificates added with
.Fn SSL_CTX_add_extra_chain_cert
are ignored when certificates are also available that have been
added using the functions documented in
.Xr SSL_CTX_set1_chain 3 .
.Pp
Only one set of extra chain certificates can be specified per
.Vt SSL_CTX
structure using
.Fn SSL_CTX_add_extra_chain_cert .
Different chains for different certificates (for example if both
RSA and ECDSA certificates are specified by the same server) or
different SSL structures with the same parent
.Vt SSL_CTX
require using the functions documented in
.Xr SSL_CTX_set1_chain 3
instead.