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

Everything used over an HTTPS proxy

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

This option is supported by the OpenSSL, GnuTLS, and mbedTLS (since 7.56.0) backends.

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)

March 12 2024 libcurl