c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Title: CURLINFO_CERTINFO Section: 3 Source: libcurl See-also:

CURLINFO_CAPATH (3)
curl_easy_getinfo (3)
curl_easy_setopt (3) Protocol:
TLS TLS-backend:
OpenSSL
GnuTLS
Schannel
Secure Transport Added-in: 7.19.1 ---

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%

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);
  }
}

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%

RETURN VALUE

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

CURLINFO_CERTINFO.md 2.4 KB History Raw