CURLOPT_PROXY_SSLKEY - specify private keyfile for TLS and SSL proxy client cert
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_SSLKEY, char *keyfile);
Pass a pointer to a zero terminated string as parameter. The string should be
the file name of your private key used for connecting to the HTTPS proxy. The
default format is "PEM" and can be changed with
(iOS and Mac OS X only) This option is ignored if curl was built against Secure
Transport. Secure Transport expects the private key to be already present in
the keychain or PKCS#12 file containing the certificate.
The application does not have to keep the string around after setting this
CURL *curl = curl_easy_init();
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_PROXY, "https://proxy");
curl_easy_setopt(curl, CURLOPT_PROXY_SSLCERT, "client.pem");
curl_easy_setopt(curl, CURLOPT_PROXY_SSLKEY, "key.pem");
curl_easy_setopt(curl, CURLOPT_PROXY_KEYPASSWD, "s3cret");
ret = curl_easy_perform(curl);
Added in 7.52.0
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.