CURLOPT_CERTINFO

Section: curl_easy_setopt options (3)
Updated: May 27, 2017
Index Return to Main Contents

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NAME

CURLOPT_CERTINFO - request SSL certificate information  

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CERTINFO, long certinfo);  

DESCRIPTION

Pass a long set to 1 to enable libcurl's certificate chain info gatherer. With this enabled, libcurl will extract lots of information and data about the certificates in the certificate chain used in the SSL connection. This data may then be retrieved after a transfer using curl_easy_getinfo(3) and its option CURLINFO_CERTINFO(3).  

DEFAULT

0  

PROTOCOLS

All TLS-based  

EXAMPLE

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);
}

 

AVAILABILITY

This option is supported by the OpenSSL, GnuTLS, NSS and GSKit backends.  

RETURN VALUE

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

SEE ALSO

CURLOPT_CAINFO(3), CURLOPT_SSL_VERIFYPEER(3),

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Index

NAME

SYNOPSIS

DESCRIPTION

DEFAULT

PROTOCOLS

EXAMPLE

AVAILABILITY

RETURN VALUE

SEE ALSO