.\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2022, Daniel Stenberg, , 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_PROXY_SSLVERSION 3 "16 Nov 2016" "libcurl 7.52.0" "curl_easy_setopt options" .SH NAME CURLOPT_PROXY_SSLVERSION \- preferred HTTPS proxy TLS version .SH SYNOPSIS .nf #include CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_SSLVERSION, long version); .fi .SH DESCRIPTION Pass a long as parameter to control which version of SSL/TLS to attempt to use when connecting to an HTTPS proxy. Use one of the available defines for this purpose. The available options are: .RS .IP CURL_SSLVERSION_DEFAULT The default action. This will attempt to figure out the remote SSL protocol version. .IP CURL_SSLVERSION_TLSv1 TLSv1.x .IP CURL_SSLVERSION_TLSv1_0 TLSv1.0 .IP CURL_SSLVERSION_TLSv1_1 TLSv1.1 .IP CURL_SSLVERSION_TLSv1_2 TLSv1.2 .IP CURL_SSLVERSION_TLSv1_3 TLSv1.3 .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 as TLSv1.2, or the default value from the SSL library. (Added in 7.54.0) .IP CURL_SSLVERSION_MAX_TLSv1_0 The flag defines maximum supported TLS version as TLSv1.0. (Added in 7.54.0) .IP CURL_SSLVERSION_MAX_TLSv1_1 The flag defines maximum supported TLS version as TLSv1.1. (Added in 7.54.0) .IP CURL_SSLVERSION_MAX_TLSv1_2 The flag defines maximum supported TLS version as TLSv1.2. (Added in 7.54.0) .IP CURL_SSLVERSION_MAX_TLSv1_3 The flag defines maximum supported TLS version as TLSv1.3. (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 .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, CURL_SSLVERSION_TLSv1); /* Perform the request */ curl_easy_perform(curl); } .fi .SH AVAILABILITY Added in 7.52.0 .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_IPRESOLVE "(3) " CURLOPT_SSLVERSION "(3), "