NAME

       CURLOPT_CAINFO - path to Certificate Authority (CA) bundle

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CAINFO, char *path);

DESCRIPTION

       Pass  a char pointer to a null-terminated string naming a file holding one or more certificates to verify
       the peer with.

       If CURLOPT_SSL_VERIFYPEER(3) is zero and you avoid verifying the server's certificate,  CURLOPT_CAINFO(3)
       need not even indicate an accessible file.

       This  option  is by default set to the system path where libcurl's CA certificate bundle is assumed to be
       stored, as established at build time.

       (iOS and macOS) When curl uses Secure Transport this option is supported. If the option is not set,  then
       curl uses the certificates in the system and user Keychain to verify the peer.

       (Schannel)  This  option  is  supported  for Schannel in Windows 7 or later but we recommend not using it
       until Windows 8 since it works better starting then.  If the option  is  not  set,  then  curl  uses  the
       certificates in the Windows' store of root certificates (the default for Schannel).

       The application does not have to keep the string around after setting this option.

       Using  this option multiple times makes the last set string override the previous ones. Set it to NULL to
       disable its use again.

       The default value for this can be figured out with CURLINFO_CAINFO(3).

DEFAULT

       Built-in system specific. When curl is built with Secure Transport or Schannel, this option is not set by
       default.

PROTOCOLS

       This functionality affects all TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.

       All TLS backends support this option.

EXAMPLE

       int main(void)
       {
         CURL *curl = curl_easy_init();
         if(curl) {
           curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
           curl_easy_setopt(curl, CURLOPT_CAINFO, "/etc/certs/cabundle.pem");
           curl_easy_perform(curl);
           curl_easy_cleanup(curl);
         }
       }

HISTORY

       Schannel support added in libcurl 7.60.

AVAILABILITY

       Added in curl 7.4.2

RETURN VALUE

       curl_easy_setopt(3) returns a CURLcode indicating success or error.

       CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).

SEE ALSO

       CURLINFO_CAINFO(3),     CURLOPT_CAINFO_BLOB(3),      CURLOPT_CAPATH(3),      CURLOPT_CA_CACHE_TIMEOUT(3),
       CURLOPT_SSL_VERIFYHOST(3), CURLOPT_SSL_VERIFYPEER(3)

libcurl                                            2025-03-05                                  CURLOPT_CAINFO(3)