121 lines
4.3 KiB
Groff
121 lines
4.3 KiB
Groff
.\" **************************************************************************
|
|
.\" * _ _ ____ _
|
|
.\" * Project ___| | | | _ \| |
|
|
.\" * / __| | | | |_) | |
|
|
.\" * | (__| |_| | _ <| |___
|
|
.\" * \___|\___/|_| \_\_____|
|
|
.\" *
|
|
.\" * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
|
|
.\" *
|
|
.\" * This software is licensed as described in the file COPYING, which
|
|
.\" * you should have received as part of this distribution. The terms
|
|
.\" * are also available at https://curl.se/docs/copyright.html.
|
|
.\" *
|
|
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
|
|
.\" * copies of the Software, and permit persons to whom the Software is
|
|
.\" * furnished to do so, under the terms of the COPYING file.
|
|
.\" *
|
|
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
|
|
.\" * KIND, either express or implied.
|
|
.\" *
|
|
.\" * SPDX-License-Identifier: curl
|
|
.\" *
|
|
.\" **************************************************************************
|
|
.\"
|
|
.TH CURLOPT_SSLVERSION 3 "August 22, 2023" "ibcurl 8.3.0" libcurl
|
|
|
|
.SH NAME
|
|
CURLOPT_SSLVERSION \- preferred TLS/SSL version
|
|
.SH SYNOPSIS
|
|
.nf
|
|
#include <curl/curl.h>
|
|
|
|
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLVERSION, long version);
|
|
.fi
|
|
.SH DESCRIPTION
|
|
Pass a long as parameter to control which version range of SSL/TLS versions to
|
|
use.
|
|
|
|
The SSL and TLS versions have typically developed from the most insecure
|
|
version to be more and more secure in this order through history: SSL v2,
|
|
SSLv3, TLS v1.0, TLS v1.1, TLS v1.2 and the most recent TLS v1.3.
|
|
|
|
Use one of the available defines for this purpose. The available options are:
|
|
.RS
|
|
.IP CURL_SSLVERSION_DEFAULT
|
|
The default acceptable version range. The minimum acceptable version is by
|
|
default TLS v1.0 since 7.39.0 (unless the TLS library has a stricter rule).
|
|
.IP CURL_SSLVERSION_TLSv1
|
|
TLS v1.0 or later
|
|
.IP CURL_SSLVERSION_SSLv2
|
|
SSL v2 - refused
|
|
.IP CURL_SSLVERSION_SSLv3
|
|
SSL v3 - refused
|
|
.IP CURL_SSLVERSION_TLSv1_0
|
|
TLS v1.0 or later (Added in 7.34.0)
|
|
.IP CURL_SSLVERSION_TLSv1_1
|
|
TLS v1.1 or later (Added in 7.34.0)
|
|
.IP CURL_SSLVERSION_TLSv1_2
|
|
TLS v1.2 or later (Added in 7.34.0)
|
|
.IP CURL_SSLVERSION_TLSv1_3
|
|
TLS v1.3 or later (Added in 7.52.0)
|
|
.RE
|
|
|
|
The maximum TLS version can be set by using \fIone\fP of the
|
|
CURL_SSLVERSION_MAX_ macros below. It is also possible to OR \fIone\fP of the
|
|
CURL_SSLVERSION_ macros with \fIone\fP of the CURL_SSLVERSION_MAX_ macros.
|
|
The MAX macros are not supported for WolfSSL.
|
|
.RS
|
|
.IP CURL_SSLVERSION_MAX_DEFAULT
|
|
The flag defines the maximum supported TLS version by libcurl, or the default
|
|
value from the SSL library is used. libcurl uses a sensible default maximum,
|
|
which was TLS v1.2 up to before 7.61.0 and is TLS v1.3 since then - assuming
|
|
the TLS library support it. (Added in 7.54.0)
|
|
.IP CURL_SSLVERSION_MAX_TLSv1_0
|
|
The flag defines maximum supported TLS version as TLS v1.0.
|
|
(Added in 7.54.0)
|
|
.IP CURL_SSLVERSION_MAX_TLSv1_1
|
|
The flag defines maximum supported TLS version as TLS v1.1.
|
|
(Added in 7.54.0)
|
|
.IP CURL_SSLVERSION_MAX_TLSv1_2
|
|
The flag defines maximum supported TLS version as TLS v1.2.
|
|
(Added in 7.54.0)
|
|
.IP CURL_SSLVERSION_MAX_TLSv1_3
|
|
The flag defines maximum supported TLS version as TLS v1.3.
|
|
(Added in 7.54.0)
|
|
.RE
|
|
|
|
In versions of curl prior to 7.54 the CURL_SSLVERSION_TLS options were
|
|
documented to allow \fIonly\fP the specified TLS version, but behavior was
|
|
inconsistent depending on the TLS library.
|
|
|
|
.SH DEFAULT
|
|
CURL_SSLVERSION_DEFAULT
|
|
.SH PROTOCOLS
|
|
All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.
|
|
.SH EXAMPLE
|
|
.nf
|
|
CURL *curl = curl_easy_init();
|
|
if(curl) {
|
|
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
|
|
|
|
/* ask libcurl to use TLS version 1.0 or later */
|
|
curl_easy_setopt(curl, CURLOPT_SSLVERSION, (long)CURL_SSLVERSION_TLSv1);
|
|
|
|
/* Perform the request */
|
|
curl_easy_perform(curl);
|
|
}
|
|
.fi
|
|
.SH AVAILABILITY
|
|
SSLv2 and SSLv3 are refused completely since curl 7.77.0
|
|
|
|
SSLv2 is disabled by default since 7.18.1. Other SSL versions availability may
|
|
vary depending on which backend libcurl has been built to use.
|
|
|
|
SSLv3 is disabled by default since 7.39.0.
|
|
.SH RETURN VALUE
|
|
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
|
|
.SH "SEE ALSO"
|
|
.BR CURLOPT_USE_SSL "(3), " CURLOPT_HTTP_VERSION "(3), "
|
|
.BR CURLOPT_PROXY_SSLVERSION "(3), " CURLOPT_IPRESOLVE "(3) "
|