106 lines
4.0 KiB
Groff
106 lines
4.0 KiB
Groff
|
.\" **************************************************************************
|
||
|
|
.\" * _ _ ____ _
|
||
|
|
.\" * Project ___| | | | _ \| |
|
||
|
|
.\" * / __| | | | |_) | |
|
||
|
|
.\" * | (__| |_| | _ <| |___
|
||
|
|
.\" * \___|\___/|_| \_\_____|
|
||
|
|
.\" *
|
||
|
|
.\" * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
|
||
|
|
.\" *
|
||
|
|
.\" * This software is licensed as described in the file COPYING, which
|
||
|
|
.\" * you should have received as part of this distribution. The terms
|
||
|
|
.\" * are also available at https://curl.se/docs/copyright.html.
|
||
|
|
.\" *
|
||
|
|
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
|
||
|
|
.\" * copies of the Software, and permit persons to whom the Software is
|
||
|
|
.\" * furnished to do so, under the terms of the COPYING file.
|
||
|
|
.\" *
|
||
|
|
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
|
||
|
|
.\" * KIND, either express or implied.
|
||
|
|
.\" *
|
||
|
|
.\" * SPDX-License-Identifier: curl
|
||
|
|
.\" *
|
||
|
|
.\" **************************************************************************
|
||
|
|
.\"
|
||
|
|
.TH CURLOPT_DOH_SSL_VERIFYPEER 3 "11 Feb 2021" libcurl libcurl
|
||
|
|
.SH NAME
|
||
|
|
CURLOPT_DOH_SSL_VERIFYPEER \- verify the DoH SSL certificate
|
||
|
|
.SH SYNOPSIS
|
||
|
|
.nf
|
||
|
|
#include <curl/curl.h>
|
||
|
|
|
||
|
|
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DOH_SSL_VERIFYPEER,
|
||
|
|
long verify);
|
||
|
|
.fi
|
||
|
|
.SH DESCRIPTION
|
||
|
|
Pass a long as parameter set to 1L to enable or 0L to disable.
|
||
|
|
|
||
|
|
This option tells curl to verify the authenticity of the DoH (DNS-over-HTTPS)
|
||
|
|
server's certificate. A value of 1 means curl verifies; 0 (zero) means it
|
||
|
|
does not.
|
||
|
|
|
||
|
|
This option is the DoH equivalent of \fICURLOPT_SSL_VERIFYPEER(3)\fP and
|
||
|
|
only affects requests to the DoH server.
|
||
|
|
|
||
|
|
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 \fICURLOPT_CAINFO(3)\fP option
|
||
|
|
or the \fICURLOPT_CAPATH(3)\fP option.
|
||
|
|
|
||
|
|
When \fICURLOPT_DOH_SSL_VERIFYPEER(3)\fP 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 \fICURLOPT_DOH_SSL_VERIFYHOST(3)\fP for that. The check
|
||
|
|
that the host name in the certificate is valid for the host name you are
|
||
|
|
connecting to is done independently of the
|
||
|
|
\fICURLOPT_DOH_SSL_VERIFYPEER(3)\fP 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.
|
||
|
|
.SH DEFAULT
|
||
|
|
1
|
||
|
|
.SH PROTOCOLS
|
||
|
|
DoH
|
||
|
|
.SH EXAMPLE
|
||
|
|
.nf
|
||
|
|
int main(void)
|
||
|
|
{
|
||
|
|
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 certificate verification of the DoH server */
|
||
|
|
curl_easy_setopt(curl, CURLOPT_DOH_SSL_VERIFYPEER, 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_CAINFO (3),
|
||
|
|
.BR CURLOPT_CAPATH (3),
|
||
|
|
.BR CURLOPT_DOH_SSL_VERIFYHOST (3),
|
||
|
|
.BR CURLOPT_PROXY_SSL_VERIFYHOST (3),
|
||
|
|
.BR CURLOPT_PROXY_SSL_VERIFYPEER (3),
|
||
|
|
.BR CURLOPT_SSL_VERIFYHOST (3),
|
||
|
|
.BR CURLOPT_SSL_VERIFYPEER (3)
|