CURLOPT_CERTINFO - request SSL certificate information
#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CERTINFO, long certinfo);
CURLOPT_CERTINFO(3) curl_easy_setopt options CURLOPT_CERTINFO(3) 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 gath- erer. 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, Schannel, NSS, GSKit and Secure Transport backends. Schannel support added in 7.50.0. Secure Transport support added in 7.79.0. RETURN VALUE Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. ATTRIBUTES See attributes(7) for descriptions of the following attributes: +---------------+------------------+ |ATTRIBUTE TYPE | ATTRIBUTE VALUE | +---------------+------------------+ |Availability | web/curl | +---------------+------------------+ |Stability | Uncommitted | +---------------+------------------+ SEE ALSO CURLOPT_CAINFO(3), CURLOPT_SSL_VERIFYPEER(3), NOTES Source code for open source software components in Oracle Solaris can be found at https://www.oracle.com/downloads/opensource/solaris-source- code-downloads.html. This software was built from source available at https://github.com/oracle/solaris-userland. The original community source was downloaded from https://curl.se/down- load/curl-7.83.1.tar.bz2. Further information about this software can be found on the open source community website at http://curl.haxx.se/. libcurl 7.83.1 November 26, 2021 CURLOPT_CERTINFO(3)