CURLOPT_SSL_VERIFYPEER(3)  curl_easy_setopt options  CURLOPT_SSL_VERIFYPEER(3)

NAME
       CURLOPT_SSL_VERIFYPEER - verify the peer's SSL certificate

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_VERIFYPEER, long
       verify);

DESCRIPTION
       Pass a long as parameter to enable or disable.

       This option determines whether curl verifies the authenticity of the
       peer's certificate. A value of 1 means curl verifies; 0 (zero) means it
       doesn't.

       When negotiating a TLS or SSL connection, the server sends a
       certificate indicating its identity.  Curl verifies whether the
       certificate is authentic, i.e. that you can trust that the server is
       who the certificate says it is.  This trust is based on a chain of
       digital signatures, rooted in certification authority (CA) certificates
       you supply.  curl uses a default bundle of CA certificates (the path
       for that is determined at build time) and you can specify alternate
       certificates with the _CAINFO&section=3">CURLOPT_CAINFO(3) option or the _CAPATH&section=3">CURLOPT_CAPATH(3)
       option.

       When _SSL_VERIFYPEER&section=3">CURLOPT_SSL_VERIFYPEER(3) is enabled, and the verification fails
       to prove that the certificate is authentic, the connection fails.  When
       the option is zero, the peer certificate verification succeeds
       regardless.

       Authenticating the certificate is not enough to be sure about the
       server. You typically also want to ensure that the server is the server
       you mean to be talking to.  Use _SSL_VERIFYHOST&section=3">CURLOPT_SSL_VERIFYHOST(3) for that. The
       check that the host name in the certificate is valid for the host name
       you're connecting to is done independently of the
       _SSL_VERIFYPEER&section=3">CURLOPT_SSL_VERIFYPEER(3) option.

       WARNING: disabling verification of the certificate allows bad guys to
       man-in-the-middle the communication without you knowing it. Disabling
       verification makes the communication insecure. Just having encryption
       on a transfer is not enough as you cannot be sure that you are
       communicating with the correct end-point.

       NOTE: even when this option is disabled, depending on the used TLS
       backend, curl may still load the certificate file specified in
       _CAINFO&section=3">CURLOPT_CAINFO(3). curl default settings in some distributions might
       use quite a large file as a default setting for _CAINFO&section=3">CURLOPT_CAINFO(3), so
       loading the file can be quite expensive, especially when dealing with
       many connections. Thus, in some situations, you might want to disable
       verification fully to save resources by setting _CAINFO&section=3">CURLOPT_CAINFO(3) to
       NULL - but please also consider the warning above!

DEFAULT
       By default, curl assumes a value of 1.

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");

         /* Set the default value: strict certificate check please */
         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1L);

         curl_easy_perform(curl);
       }

AVAILABILITY
       If built TLS enabled.

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

SEE ALSO
       CURLOPT_SSL_VERIFYHOST(3),  CURLOPT_PROXY_SSL_VERIFYPEER(3),
       CURLOPT_PROXY_SSL_VERIFYHOST(3),  CURLOPT_CAINFO(3),

libcurl 7.77.0                 November 4, 2020      CURLOPT_SSL_VERIFYPEER(3)