NAME

       CURLOPT_PROXY_CRLFILE - HTTPS proxy Certificate Revocation List file

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_CRLFILE, char *file);

DESCRIPTION

       This option is for connecting to an HTTPS proxy, not an HTTPS server.

       Pass  a  char  pointer  to  a  null-terminated string naming a file with the concatenation of CRL (in PEM
       format) to use in the certificate validation that occurs during the SSL exchange.

       When curl is built to use GnuTLS, there is no way to influence the use of  CRL  passed  to  help  in  the
       verification   process.   When   libcurl   is  built  with  OpenSSL  support,  X509_V_FLAG_CRL_CHECK  and
       X509_V_FLAG_CRL_CHECK_ALL are both set, requiring CRL check against all the elements of  the  certificate
       chain if a CRL file is passed.

       This option makes sense only when used in combination with the CURLOPT_PROXY_SSL_VERIFYPEER(3) option.

       A  specific  error  code  (CURLE_SSL_CRL_BADFILE) is defined with the option. It is returned when the SSL
       exchange fails because the CRL file cannot be loaded.  A failure in certificate  verification  due  to  a
       revocation information found in the CRL does not trigger this specific error.

       The application does not have to keep the string around after setting this option.

DEFAULT

       NULL

PROTOCOLS

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

       This option works only with the following TLS backends: GnuTLS, OpenSSL and mbedTLS

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, "https://localhost:80");
           curl_easy_setopt(curl, CURLOPT_PROXY_CRLFILE, "/etc/certs/crl.pem");
           res = curl_easy_perform(curl);
           curl_easy_cleanup(curl);
         }
       }

AVAILABILITY

       Added in curl 7.52.0

RETURN VALUE

       Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not, or CURLE_OUT_OF_MEMORY if there
       was insufficient heap space.

SEE ALSO

       CURLOPT_PROXY_SSL_VERIFYHOST(3),       CURLOPT_PROXY_SSL_VERIFYPEER(3),        CURLOPT_SSL_VERIFYHOST(3),
       CURLOPT_SSL_VERIFYPEER(3)