CURLOPT_PROXY_SSLVERSION − preferred HTTPS proxy TLS version
#include <curl/curl.h>
CURLcode
curl_easy_setopt(CURL *handle, CURLOPT_PROXY_SSLVERSION,
long version);
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:
CURL_SSLVERSION_DEFAULT
The default action. This attempts to figure out the remote SSL protocol version.
CURL_SSLVERSION_TLSv1
TLSv1.x
CURL_SSLVERSION_TLSv1_0
TLSv1.0
CURL_SSLVERSION_TLSv1_1
TLSv1.1
CURL_SSLVERSION_TLSv1_2
TLSv1.2
CURL_SSLVERSION_TLSv1_3
TLSv1.3
The maximum TLS
version can be set by using one of the
CURL_SSLVERSION_MAX_ macros below. It is also possible to OR
one of the CURL_SSLVERSION_ macros with one of
the CURL_SSLVERSION_MAX_ macros. The MAX macros are not
supported for wolfSSL.
CURL_SSLVERSION_MAX_DEFAULT
The flag defines the maximum supported TLS version as TLSv1.2, or the default value from the SSL library.
CURL_SSLVERSION_MAX_TLSv1_0
The flag defines maximum supported TLS version as TLSv1.0.
CURL_SSLVERSION_MAX_TLSv1_1
The flag defines maximum supported TLS version as TLSv1.1.
CURL_SSLVERSION_MAX_TLSv1_2
The flag defines maximum supported TLS version as TLSv1.2.
CURL_SSLVERSION_MAX_TLSv1_3
The flag defines maximum supported TLS version as TLSv1.3.
CURL_SSLVERSION_DEFAULT
This functionality affects all TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.
All TLS backends support this option.
int main(void)
{
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);
}
}
CURL_SSLVERSION_* macros became long types in 8.16.0, prior to this version a long cast was necessary when passed to curl_easy_setopt(3).
Added in curl 7.52.0
curl_easy_setopt(3) returns a CURLcode indicating success or error.
CURLE_OK (0) means everything was OK, non−zero means an error occurred, see libcurl−errors(3).
CURLOPT_HTTP_VERSION(3), CURLOPT_IPRESOLVE(3), CURLOPT_SSLVERSION(3), CURLOPT_USE_SSL(3)