NAME

       CURLOPT_SSL_CIPHER_LIST - ciphers to use for TLS

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_CIPHER_LIST, char *list);

DESCRIPTION

       Pass  a  char  *,  pointing  to  a  null-terminated string holding the list of ciphers to use for the SSL
       connection. The list must be syntactically correct, it consists of one or more cipher  strings  separated
       by  colons.  Commas or spaces are also acceptable separators but colons are normally used, !, - and + can
       be used as operators.

       For OpenSSL and GnuTLS valid examples of cipher lists include RC4-SHA, SHA1+DES, TLSv1 and  DEFAULT.  The
       default list is normally set when you compile OpenSSL.

       For WolfSSL, valid examples of cipher lists include ECDHE-RSA-RC4-SHA, AES256-SHA:AES256-SHA256, etc.

       For  BearSSL,  valid  examples  of cipher lists include ECDHE-RSA-CHACHA20-POLY1305:ECDHE-RSA-AES128-GCM-
       SHA256,               or               when                using                IANA                names
       TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256:TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, etc.  With BearSSL you
       do  not  add/remove  ciphers.  If one uses this option then all known ciphers are disabled and only those
       passed in are enabled.

       For Schannel, you can use this option to set algorithms but not specific  cipher  suites.  Refer  to  the
       ciphers lists document for algorithms.

       Find more details about cipher lists on this URL:

        https://curl.se/docs/ssl-ciphers.html

       The application does not have to keep the string around after setting this option.

DEFAULT

       NULL, use internal default

PROTOCOLS

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

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_CIPHER_LIST, "TLSv1");
           res = curl_easy_perform(curl);
           curl_easy_cleanup(curl);
         }
       }

AVAILABILITY

       Added in 7.9, in 7.83.0 for BearSSL

       If built TLS enabled.

RETURN VALUE

       Returns  CURLE_OK  if  TLS is supported, CURLE_UNKNOWN_OPTION if not, or CURLE_OUT_OF_MEMORY if there was
       insufficient heap space.

SEE ALSO

       CURLOPT_TLS13_CIPHERS(3),            CURLOPT_SSLVERSION(3),             CURLOPT_PROXY_SSL_CIPHER_LIST(3),
       CURLOPT_PROXY_TLS13_CIPHERS(3), CURLOPT_USE_SSL(3)

ibcurl 8.5.0                                    December 04, 2023                     CURLOPT_SSL_CIPHER_LIST(3)