NAME

       CURLOPT_SSLKEYTYPE - type of the private key file

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLKEYTYPE, char *type);

DESCRIPTION

       Pass  a pointer to a null-terminated string as parameter. The string should be the format of your private
       key. Supported formats are "PEM", "DER", "ENG" and "PROV".

       The format "ENG" enables you to load the private key from a crypto engine. In this case CURLOPT_SSLKEY(3)
       is  used  as  an  identifier  passed  to  the  engine.  You  have  to  set   the   crypto   engine   with
       CURLOPT_SSLENGINE(3).

       The  format  "PROV" enables you to load the private key from a crypto provider (Added in 8.12.0). In this
       case CURLOPT_SSLKEY(3) is used as an identifier passed to the provider.

       The "DER" format does not work with OpenSSL.

       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
       restore to internal default.

DEFAULT

       "PEM"

PROTOCOLS

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

       This option works only with the following TLS backends: BearSSL, OpenSSL 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_SSLCERT, "client.pem");
           curl_easy_setopt(curl, CURLOPT_SSLKEY, "key.pem");
           curl_easy_setopt(curl, CURLOPT_SSLKEYTYPE, "PEM");
           curl_easy_setopt(curl, CURLOPT_KEYPASSWD, "s3cret");
           res = curl_easy_perform(curl);
           curl_easy_cleanup(curl);
         }
       }

AVAILABILITY

       Added in curl 7.9.3

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_SSLKEYTYPE(3), CURLOPT_SSLCERT(3), CURLOPT_SSLKEY(3)

libcurl                                            2025-06-16                              CURLOPT_SSLKEYTYPE(3)