CURLOPT_PROXY_CAPATH(3) Library Functions Manual CURLOPT_PROXY_CAPATH(3)

CURLOPT_PROXY_CAPATH - directory holding HTTPS proxy CA certificates

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_CAPATH, char *capath);

Pass a char pointer to a null-terminated string naming a directory holding multiple CA certificates to verify the HTTPS proxy with. If libcurl is built against OpenSSL, the certificate directory must be prepared using the OpenSSL c_rehash utility. This makes sense only when CURLOPT_PROXY_SSL_VERIFYPEER(3) is enabled (which it is by default).

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

The default value for this can be figured out with CURLINFO_CAPATH(3).

NULL

All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.

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

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    /* using an HTTPS proxy */
    curl_easy_setopt(curl, CURLOPT_PROXY, "https://localhost:443");
    curl_easy_setopt(curl, CURLOPT_PROXY_CAPATH, "/etc/cert-dir");
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

Added in 7.52.0

mbedTLS support added in 7.56.0.

CURLE_OK if supported; or an error such as:

CURLE_NOT_BUILT_IN - Not supported by the SSL backend

CURLE_UNKNOWN_OPTION

CURLE_OUT_OF_MEMORY

CURLOPT_CAINFO(3), CURLOPT_DEBUGFUNCTION(3), CURLOPT_PROXY_CAINFO(3), CURLOPT_PROXY_SSL_VERIFYHOST(3), CURLOPT_STDERR(3)

April 02 2024 libcurl