Ubuntu Manpage: CURLOPT_PROXY_SSL_CIPHER_LIST - ciphers to use for HTTPS proxy

NAME

       CURLOPT_PROXY_SSL_CIPHER_LIST - ciphers to use for HTTPS proxy

SYNOPSIS

       #include <curl/curl.h>

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

DESCRIPTION

Pass a char *, pointing to a null-terminated string holding the list of ciphers to use for
the connection to the HTTPS proxy. 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 NSS, valid examples of cipher lists include rsa_rc4_128_md5, rsa_aes_128_sha, etc.
With NSS 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 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.

you will 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

EXAMPLE

       CURL *curl = curl_easy_init();
       if(curl) {
         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
         curl_easy_setopt(curl, CURLOPT_PROXY, "https://localhost");
         curl_easy_setopt(curl, CURLOPT_PROXY_SSL_CIPHER_LIST, "TLSv1");
         ret = curl_easy_perform(curl);
         curl_easy_cleanup(curl);
       }

AVAILABILITY

       Added in 7.52.0, 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.