curl/docs/libcurl/opts/CURLINFO_CERTINFO.3

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.TH CURLINFO_CERTINFO 3 "12 Sep 2015" "libcurl" "libcurl"
.SH NAME
CURLINFO_CERTINFO \- get the TLS certificate chain
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_CERTINFO,
                           struct curl_certinfo **chainp);
.fi
.SH DESCRIPTION
Pass a pointer to a \fIstruct curl_certinfo *\fP and you will get it set to
point to a 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 \fIcertinfo.c\fP 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, GSKit
or Secure Transport support. Schannel support added in 7.50.0. Secure Transport
support added in 7.79.0.

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), "