CURLINFO_CERTINFO(3) Library Functions Manual CURLINFO_CERTINFO(3)
NAME
CURLINFO_CERTINFO - get the TLS certificate chain
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_CERTINFO,
struct curl_certinfo **chainp);
DESCRIPTION
Pass a pointer to a struct curl_certinfo * and it is set to point to a
struct that holds info about the server's certificate chain, assuming
you had CURLOPT_CERTINFO(3) enabled when the request was made.
struct curl_certinfo {
int num_of_certs;
struct curl_slist **certinfo;
};
The certinfo struct member is an array of linked lists of certificate
information. The num_of_certs struct member is the number of
certificates which is the number of elements in the array. Each
certificate's list has items with textual information in the format
"name:content" such as "Subject:Foo", "Issuer:Bar", etc. The items in
each list varies depending on the SSL backend and the certificate.
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, Schannel and Secure Transport
EXAMPLE
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
curl_easy_setopt(curl, CURLOPT_URL, "https://www.example.com/");
/* connect to any HTTPS site, trusted or not */
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
curl_easy_setopt(curl, CURLOPT_CERTINFO, 1L);
res = curl_easy_perform(curl);
if(!res) {
int i;
struct curl_certinfo *ci;
res = curl_easy_getinfo(curl, CURLINFO_CERTINFO, &ci);
if(!res) {
printf("%d certs!\n", ci->num_of_certs);
for(i = 0; i < ci->num_of_certs; i++) {
struct curl_slist *slist;
for(slist = ci->certinfo[i]; slist; slist = slist->next)
printf("%s\n", slist->data);
}
}
}
curl_easy_cleanup(curl);
}
}
See also the certinfo.c example.
HISTORY
GnuTLS support added in 7.42.0. Schannel support added in 7.50.0.
Secure Transport support added in 7.79.0. mbedTLS support added in
8.9.0.
AVAILABILITY
Added in curl 7.19.1
RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
if not.
SEE ALSO
CURLINFO_CAPATH(3), curl_easy_getinfo(3), curl_easy_setopt(3)
libcurl 2024-08-05 CURLINFO_CERTINFO(3)
curl 8.9.1 - Generated Mon Aug 12 08:38:13 CDT 2024