CURLOPT_SSLVERSION(3)					     curl_easy_setopt options					     CURLOPT_SSLVERSION(3)

NAME

       CURLOPT_SSLVERSION - set preferred TLS/SSL version

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLVERSION, long version);

DESCRIPTION

       Pass a long as parameter to control which version of SSL/TLS to attempt to use.

       Use one of the available defines for this purpose. The available options are:

	      CURL_SSLVERSION_DEFAULT
		     The default action. This will attempt to figure out the remote SSL protocol version.

	      CURL_SSLVERSION_TLSv1
		     TLSv1.x

	      CURL_SSLVERSION_SSLv2
		     SSLv2

	      CURL_SSLVERSION_SSLv3
		     SSLv3

	      CURL_SSLVERSION_TLSv1_0
		     TLSv1.0 (Added in 7.34.0)

	      CURL_SSLVERSION_TLSv1_1
		     TLSv1.1 (Added in 7.34.0)

	      CURL_SSLVERSION_TLSv1_2
		     TLSv1.2 (Added in 7.34.0)

	      CURL_SSLVERSION_TLSv1_3
		     TLSv1.3 (Added in 7.52.0)

	      CURL_SSLVERSION_MAX_DEFAULT
		     The  flag	defines  maximum  supported  TLS  version as TLSv1.2 or default value from SSL library. Only library NSS currently
		     allows to get maximum supported TLS version.  (Added in 7.54.0)

	      CURL_SSLVERSION_MAX_TLSv1_0
		     The flag defines maximum supported TLS version as TLSv1.0.  (Added in 7.54.0)

	      CURL_SSLVERSION_MAX_TLSv1_1
		     The flag defines maximum supported TLS version as TLSv1.1.  (Added in 7.54.0)

	      CURL_SSLVERSION_MAX_TLSv1_2
		     The flag defines maximum supported TLS version as TLSv1.2.  (Added in 7.54.0)

	      CURL_SSLVERSION_MAX_TLSv1_3
		     The flag defines maximum supported TLS version as TLSv1.3.  (Added in 7.54.0)

DEFAULT

       CURL_SSLVERSION_DEFAULT

PROTOCOLS

       All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.

EXAMPLE

       CURL *curl = curl_easy_init();
       if(curl) {
	 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

	 /* ask libcurl to use TLS version 1.1 or later */
	 curl_easy_setopt(curl, CURLOPT_SSLVERSION, CURL_SSLVERSION_TLSv1.1 |
			  CURL_SSLVERSION_MAX_DEFAULT);

	 /* Perform the request */
	 curl_easy_perform(curl);
       }

AVAILABILITY

       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.

RETURN VALUE

       Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

SEE ALSO

       CURLOPT_USE_SSL(3), CURLOPT_HTTP_VERSION(3), CURLOPT_IPRESOLVE(3)

libcurl 7.54.0							 December 13, 2016					     CURLOPT_SSLVERSION(3)