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        !            23: .TH CURLOPT_SSL_VERIFYPEER 3 "June 24, 2018" "libcurl 7.70.0" "curl_easy_setopt options"
        !            24: 
        !            25: .SH NAME
        !            26: CURLOPT_SSL_VERIFYPEER \- verify the peer's SSL certificate
        !            27: .SH SYNOPSIS
        !            28: #include <curl/curl.h>
        !            29: 
        !            30: CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_VERIFYPEER, long verify);
        !            31: .SH DESCRIPTION
        !            32: Pass a long as parameter to enable or disable.
        !            33: 
        !            34: This option determines whether curl verifies the authenticity of the peer's
        !            35: certificate. A value of 1 means curl verifies; 0 (zero) means it doesn't.
        !            36: 
        !            37: When negotiating a TLS or SSL connection, the server sends a certificate
        !            38: indicating its identity.  Curl verifies whether the certificate is authentic,
        !            39: i.e. that you can trust that the server is who the certificate says it is.
        !            40: This trust is based on a chain of digital signatures, rooted in certification
        !            41: authority (CA) certificates you supply.  curl uses a default bundle of CA
        !            42: certificates (the path for that is determined at build time) and you can
        !            43: specify alternate certificates with the \fICURLOPT_CAINFO(3)\fP option or the
        !            44: \fICURLOPT_CAPATH(3)\fP option.
        !            45: 
        !            46: When \fICURLOPT_SSL_VERIFYPEER(3)\fP is enabled, and the verification fails to
        !            47: prove that the certificate is authentic, the connection fails.  When the
        !            48: option is zero, the peer certificate verification succeeds regardless.
        !            49: 
        !            50: Authenticating the certificate is not enough to be sure about the server. You
        !            51: typically also want to ensure that the server is the server you mean to be
        !            52: talking to.  Use \fICURLOPT_SSL_VERIFYHOST(3)\fP for that. The check that the
        !            53: host name in the certificate is valid for the host name you're connecting to
        !            54: is done independently of the \fICURLOPT_SSL_VERIFYPEER(3)\fP option.
        !            55: 
        !            56: WARNING: disabling verification of the certificate allows bad guys to
        !            57: man-in-the-middle the communication without you knowing it. Disabling
        !            58: verification makes the communication insecure. Just having encryption on a
        !            59: transfer is not enough as you cannot be sure that you are communicating with
        !            60: the correct end-point.
        !            61: 
        !            62: NOTE: even when this option is disabled, depending on the used TLS backend,
        !            63: curl may still load the certificate file specified in
        !            64: \fICURLOPT_CAINFO(3)\fP. curl default settings in some distributions might use
        !            65: quite a large file as a default setting for \fICURLOPT_CAINFO(3)\fP, so
        !            66: loading the file can be quite expensive, especially when dealing with many
        !            67: connections. Thus, in some situations, you might want to disable verification
        !            68: fully to save resources by setting \fICURLOPT_CAINFO(3)\fP to NULL - but
        !            69: please also consider the warning above!
        !            70: .SH DEFAULT
        !            71: By default, curl assumes a value of 1.
        !            72: .SH PROTOCOLS
        !            73: All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.
        !            74: .SH EXAMPLE
        !            75: .nf
        !            76: CURL *curl = curl_easy_init();
        !            77: if(curl) {
        !            78:   curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
        !            79: 
        !            80:   /* Set the default value: strict certificate check please */
        !            81:   curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1L);
        !            82: 
        !            83:   curl_easy_perform(curl);
        !            84: }
        !            85: .fi
        !            86: .SH AVAILABILITY
        !            87: If built TLS enabled.
        !            88: .SH RETURN VALUE
        !            89: Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
        !            90: .SH "SEE ALSO"
        !            91: .BR CURLOPT_SSL_VERIFYHOST "(3), "
        !            92: .BR CURLOPT_PROXY_SSL_VERIFYPEER "(3), "
        !            93: .BR CURLOPT_PROXY_SSL_VERIFYHOST "(3), "
        !            94: .BR CURLOPT_CAINFO "(3), "