CURLOPT_PROXY_ISSUERCERT(3)curl_easy_setopt optionsCURLOPT_PROXY_ISSUERCERT(3)
NAME
CURLOPT_PROXY_ISSUERCERT - proxy issuer SSL certificate filename
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_ISSUERCERT, char *file);
DESCRIPTION
Pass a char * to a null-terminated string naming a file holding a CA
certificate in PEM format. If the option is set, an additional check
against the peer certificate is performed to verify the issuer of the
the HTTPS proxy is indeed the one associated with the certificate pro-
vided by the option. This additional check is useful in multi-level
PKI where one needs to enforce that the peer certificate is from a spe-
cific branch of the tree.
This option makes sense only when used in combination with the CUR-
LOPT_PROXY_SSL_VERIFYPEER(3) option. Otherwise, the result of the check
is not considered as failure.
A specific error code (CURLE_SSL_ISSUER_ERROR) is defined with the op-
tion, which is returned if the setup of the SSL/TLS session has failed
due to a mismatch with the issuer of peer certificate (CUR-
LOPT_PROXY_SSL_VERIFYPEER(3) has to be set too for the check to fail).
The application does not have to keep the string around after setting
this option.
DEFAULT
NULL
PROTOCOLS
All TLS-based protocols
EXAMPLE
CURL *curl = curl_easy_init();
if(curl) {
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_ISSUERCERT, "/etc/certs/cacert.pem");
ret = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
AVAILABILITY
Added in 7.71.0. This option is supported by the OpenSSL backends.
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_VERIFYPEER(3), CURLOPT_PROXY_SSL_VERIFYHOST(3), CUR-
LOPT_SSL_VERIFYPEER(3), CURLOPT_SSL_VERIFYHOST(3),
libcurl 7.81.0 November 26, 2021 CURLOPT_PROXY_ISSUERCERT(3)
Generated by dwww version 1.14 on Thu Jan 23 06:12:37 CET 2025.