DragonFly On-Line Manual Pages
CURLOPT_SSL_CIPHER_LIST(3) curl_easy_setopt options
CURLOPT_SSL_CIPHER_LIST - ciphers to use for TLS
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_CIPHER_LIST, char *list);
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
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,
For BearSSL, valid examples of cipher lists include ECDHE-RSA-
CHACHA20-POLY1305:ECDHE-RSA-AES128-GCM-SHA256, or when using IANA names
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
you will find more details about cipher lists on this URL:
The application does not have to keep the string around after setting
NULL, use internal default
All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.
CURL *curl = curl_easy_init();
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_SSL_CIPHER_LIST, "TLSv1");
ret = curl_easy_perform(curl);
Added in 7.9, in 7.83.0 for BearSSL
If built TLS enabled.
Returns CURLE_OK if TLS is supported, CURLE_UNKNOWN_OPTION if not, or
CURLE_OUT_OF_MEMORY if there was insufficient heap space.
libcurl 7.87.0 May 17, 2022 CURLOPT_SSL_CIPHER_LIST(3)