CURLOPT_SSL_EC_CURVES(3) Library Functions Manual CURLOPT_SSL_EC_CURVES(3)
NAME
CURLOPT_SSL_EC_CURVES - key exchange curves
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_EC_CURVES, char *list);
DESCRIPTION
Pass a string as parameter with a colon delimited list of Elliptic
curve (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).
The application does not have to keep the string around after setting
this option.
Using this option multiple times makes the last set string override the
previous ones. Set it to NULL to restore back to internal default.
DEFAULT
"", embedded in SSL backend
PROTOCOLS
This functionality affects all TLS based protocols: HTTPS, FTPS, IMAPS,
POP3S, SMTPS etc.
This option works only with the following TLS backends: OpenSSL and
wolfSSL
EXAMPLE
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_SSL_EC_CURVES, "X25519:P-521");
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}
AVAILABILITY
Added in curl 7.73.0
RETURN VALUE
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).
SEE ALSO
CURLOPT_SSL_CIPHER_LIST(3), CURLOPT_SSL_OPTIONS(3),
CURLOPT_TLS13_CIPHERS(3)
libcurl 2025-02-08 CURLOPT_SSL_EC_CURVES(3)
curl 8.12.0 - Generated Wed Feb 19 08:46:04 CST 2025