.\" generated by cd2nroff 0.1 from CURLOPT_TLS13_CIPHERS.md .TH CURLOPT_TLS13_CIPHERS 3 libcurl .SH NAME CURLOPT_TLS13_CIPHERS \- ciphers suites to use for TLS 1.3 .SH SYNOPSIS .nf #include CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TLS13_CIPHERS, char *list); .fi .SH DESCRIPTION Pass a char pointer, pointing to a null\-terminated string holding the list of cipher suites to use for the TLS 1.3 connection. The list must be syntactically correct, it consists of one or more cipher suite strings separated by colons. Find more details about cipher lists on this URL: https://curl.se/docs/ssl\-ciphers.html This option is currently used only when curl is built to use OpenSSL 1.1.1 or later, or Schannel. If you are using a different SSL backend you can try setting TLS 1.3 cipher suites by using the \fICURLOPT_SSL_CIPHER_LIST(3)\fP option. The application does not have to keep the string around after setting this option. .SH DEFAULT NULL, use internal default .SH PROTOCOLS All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc. This option works only with the following TLS backends: OpenSSL, Schannel and rustls .SH EXAMPLE .nf 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_TLS13_CIPHERS, "TLS_CHACHA20_POLY1305_SHA256"); res = curl_easy_perform(curl); curl_easy_cleanup(curl); } } .fi .SH AVAILABILITY Added in 7.61.0 for OpenSSL. Available when built with OpenSSL >= 1.1.1. Added in 7.85.0 for Schannel. .SH RETURN VALUE Returns CURLE_OK if supported, CURLE_NOT_BUILT_IN otherwise. .SH SEE ALSO .BR CURLOPT_PROXY_SSLVERSION (3), .BR CURLOPT_PROXY_SSL_CIPHER_LIST (3), .BR CURLOPT_PROXY_TLS13_CIPHERS (3), .BR CURLOPT_SSLVERSION (3), .BR CURLOPT_SSL_CIPHER_LIST (3), .BR CURLOPT_USE_SSL (3)