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Updated: Wednesday, July 27, 2022
 
 

CURLOPT_CAINFO (3)

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

CURLOPT_CAINFO(3)          curl_easy_setopt options          CURLOPT_CAINFO(3)



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 * 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 cacert
       bundle is assumed to be stored, as established at build time.

       If  curl is built against the NSS SSL library, the NSS PEM PKCS#11 mod-
       ule (libnsspem.so) needs to be available for this option to work  prop-
       erly.   Starting  with  curl-7.55.0, if both CURLOPT_CAINFO(3) and CUR-
       LOPT_CAPATH(3) are unset, NSS-linked  libcurl  tries  to  load  libnss-
       ckbi.so,  which  contains a more comprehensive set of trust information
       than supported by nss-pem, because libnssckbi.so also includes informa-
       tion about distrusted certificates.

       (iOS  and  macOS)  When  curl uses Secure Transport this option is sup-
       ported. If the option is not set, then curl will use  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 will use the cer-
       tificates 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.

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

PROTOCOLS
       All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.

EXAMPLE
       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");
         ret = curl_easy_perform(curl);
         curl_easy_cleanup(curl);
       }

AVAILABILITY
       For  the  SSL  engines  that  do not support certificate files the CUR-
       LOPT_CAINFO option is ignored. Schannel support added in libcurl 7.60.

RETURN VALUE
       Returns CURLE_OK if the option is  supported,  CURLE_UNKNOWN_OPTION  if
       not, or CURLE_OUT_OF_MEMORY if there was insufficient heap space.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | web/curl         |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+

SEE ALSO
       CURLOPT_CAINFO_BLOB(3),  CURLOPT_CAPATH(3),  CURLOPT_SSL_VERIFYPEER(3),
       CURLOPT_SSL_VERIFYHOST(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_CAINFO(3)