curl/docs/libcurl/opts/CURLOPT_DOH_SSL_VERIFYHOST.3

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.TH CURLOPT_DOH_SSL_VERIFYHOST 3 "11 Feb 2021" "libcurl 7.76.0" "curl_easy_setopt options"
.SH NAME
CURLOPT_DOH_SSL_VERIFYHOST \- verify the host name in the DoH SSL certificate
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DOH_SSL_VERIFYHOST,
                          long verify);
.fi
.SH DESCRIPTION
Pass a long set to 2L as asking curl to \fIverify\fP the DoH (DNS-over-HTTPS)
server's certificate name fields against the host name.

This option is the DoH equivalent of \fICURLOPT_SSL_VERIFYHOST(3)\fP and
only affects requests to the DoH server.

When \fICURLOPT_DOH_SSL_VERIFYHOST(3)\fP is 2, the SSL certificate provided by
the DoH server must indicate that the server name is the same as the server
name to which you meant to connect to, or the connection fails.

Curl considers the DoH server the intended one when the Common Name field or a
Subject Alternate Name field in the certificate matches the host name in the
DoH URL to which you told Curl to connect.

When the \fIverify\fP value is set to 1L it is treated the same as 2L. However
for consistency with the other VERIFYHOST options we suggest use 2 and not 1.

When the \fIverify\fP value is set to 0L, the connection succeeds regardless of
the names used in the certificate. Use that ability with caution!

See also \fICURLOPT_DOH_SSL_VERIFYPEER(3)\fP to verify the digital signature
of the DoH server certificate.  If libcurl is built against NSS and
\fICURLOPT_DOH_SSL_VERIFYPEER(3)\fP is zero,
\fICURLOPT_DOH_SSL_VERIFYHOST(3)\fP is also set to zero and cannot be
overridden.
.SH DEFAULT
2
.SH PROTOCOLS
DoH
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

  curl_easy_setopt(curl, CURLOPT_DOH_URL, "https://cloudflare-dns.com/dns-query");

  /* Disable host name verification of the DoH server */
  curl_easy_setopt(curl, CURLOPT_DOH_SSL_VERIFYHOST, 0L);

  curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
Added in 7.76.0

If built TLS enabled.
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLOPT_DOH_SSL_VERIFYPEER "(3), "
.BR CURLOPT_SSL_VERIFYHOST "(3), "
.BR CURLOPT_SSL_VERIFYPEER "(3), "
.BR CURLOPT_PROXY_SSL_VERIFYPEER "(3), "
.BR CURLOPT_PROXY_SSL_VERIFYHOST "(3), "