DOKK / manpages / debian 11 / libcurl4-doc / CURLOPT_SSL_EC_CURVES.3.en
CURLOPT_SSL_EC_CURVES(3) curl_easy_setopt options CURLOPT_SSL_EC_CURVES(3)

CURLOPT_SSL_EC_CURVES - set key exchange curves

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_EC_CURVES, char *alg_list);

Pass a string as parameter with a colon delimited list of (EC) algorithms. This option defines the client's key exchange algorithms in the SSL handshake (if the SSL backend libcurl is built to use supports it).

"", embedded in SSL backend

HTTP

CURL *curl = curl_easy_init();
if(curl) {

curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_SSL_EC_CURVES, "X25519:P-521");
ret = curl_easy_perform(curl);
curl_easy_cleanup(curl); }

Added in 7.73.0. Supported by the OpenSSL backend.

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

CURLOPT_SSL_OPTIONS(3), CURLOPT_SSL_CIPHER_LIST(3), CURLOPT_TLS13_CIPHERS(3),

November 4, 2020 libcurl 7.74.0