.\" **************************************************************************
.\" *                                  _   _ ____  _
.\" *  Project                     ___| | | |  _ \| |
.\" *                             / __| | | | |_) | |
.\" *                            | (__| |_| |  _ <| |___
.\" *                             \___|\___/|_| \_\_____|
.\" *
.\" * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
.\" *
.\" * This software is licensed as described in the file COPYING, which
.\" * you should have received as part of this distribution. The terms
.\" * are also available at https://curl.haxx.se/docs/copyright.html.
.\" *
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
.\" * copies of the Software, and permit persons to whom the Software is
.\" * furnished to do so, under the terms of the COPYING file.
.\" *
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
.\" * KIND, either express or implied.
.\" *
.\" **************************************************************************
.\"
.TH CURLINFO_CERTINFO 3 "May 06, 2017" "libcurl 7.59.0" "curl_easy_getinfo options"

.SH NAME
CURLINFO_CERTINFO \- get the TLS certificate chain
.SH SYNOPSIS
#include <curl/curl.h>

CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_CERTINFO,
                           struct curl_certinfo *chainp);
.SH DESCRIPTION
Pass a pointer to a 'struct curl_certinfo *' and you'll get it set to point to
struct that holds a number of linked lists with info about the certificate
chain, assuming you had \fICURLOPT_CERTINFO(3)\fP enabled when the request was
made. The struct reports how many certs it found and then you can extract info
for each of those certs by following the linked lists. The info chain is
provided in a series of data in the format "name:content" where the content is
for the specific named data. See also the certinfo.c example.
.SH PROTOCOLS
All TLS-based
.SH EXAMPLE
.nf
curl = curl_easy_init();
if(curl) {
  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) {
    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);
}
.fi
.SH AVAILABILITY
This option is only working in libcurl built with OpenSSL, NSS, schannel or
GSKit support. schannel support added in 7.50.0

Added in 7.19.1
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR curl_easy_getinfo "(3), " curl_easy_setopt "(3), "