CURLOPT_PROXY_TLS13_CIPHERS(3)                        Library Functions Manual

NAME
       CURLOPT_PROXY_TLS13_CIPHERS - ciphers suites for proxy TLS 1.3

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_TLS13_CIPHERS,
                                 char *list);

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 to a proxy. The
       list must be syntactically correct, it consists of one or more cipher
       suite strings separated by colons.

       For setting TLS 1.2 (1.1, 1.0) ciphers see
       CURLOPT_PROXY_SSL_CIPHER_LIST(3).

       A valid example of a cipher list is:
       "TLS_AES_128_GCM_SHA256:TLS_CHACHA20_POLY1305_SHA256"

       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.

       Using this option multiple times makes the last set string override the
       previous ones. Set it to NULL to disable its use again.

DEFAULT
       NULL, use internal built-in list

PROTOCOLS
       This functionality affects all TLS based protocols: HTTPS, FTPS, IMAPS,
       POP3S, SMTPS etc.

       This option works only with the following TLS backends: OpenSSL,
       mbedTLS, rustls 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_PROXY_TLS13_CIPHERS,
                            "TLS_CHACHA20_POLY1305_SHA256");
           res = curl_easy_perform(curl);
           curl_easy_cleanup(curl);
         }
       }

HISTORY
       OpenSSL support added in 7.61.0, available when built with OpenSSL >=
       1.1.1.  LibreSSL support added in 8.3.0, available when built with
       LibreSSL >= 3.4.1.  wolfSSL support added in 8.10.0.  mbedTLS support
       added in 8.10.0, available when built with mbedTLS >= 3.6.0.  Rustls
       support added in 8.10.0.

       Before curl 8.10.0 with mbedTLS or wolfSSL, TLS 1.3 cipher suites were
       set by using the CURLOPT_PROXY_SSL_CIPHER_LIST(3) option.

AVAILABILITY
       Added in curl 7.61.0

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_PROXY_SSLVERSION(3), CURLOPT_PROXY_SSL_CIPHER_LIST(3),
       CURLOPT_SSLVERSION(3), CURLOPT_SSL_CIPHER_LIST(3),
       CURLOPT_TLS13_CIPHERS(3)

libcurl                           2025-02-13    CURLOPT_PROXY_TLS13_CIPHERS(3)