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Updated: Wednesday, July 27, 2022
 
 

CURLOPT_DOH_URL (3)

Name

CURLOPT_DOH_URL - HTTPS URL

Synopsis

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DOH_URL, char *URL);

Description

CURLOPT_DOH_URL(3)         curl_easy_setopt options         CURLOPT_DOH_URL(3)



NAME
       CURLOPT_DOH_URL - provide the DNS-over-HTTPS URL

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DOH_URL, char *URL);

DESCRIPTION
       Pass  in  a pointer to a URL for the DoH server to use for name resolv-
       ing. The parameter should be a char * to a null-terminated string which
       must  be URL-encoded in the following format: "https://host:port/path".
       It MUST specify an HTTPS URL.

       libcurl does not validate the syntax or use  this  variable  until  the
       transfer   is   issued.   Even   if   you   set  a  crazy  value  here,
       curl_easy_setopt(3) will still return CURLE_OK.

       curl sends POST requests to the given DNS-over-HTTPS URL.

       To find the DoH server itself, which might be specified using  a  name,
       libcurl  will  use  the default name lookup function. You can bootstrap
       that  by  providing  the  address  for  the  DoH   server   with   CUR-
       LOPT_RESOLVE(3).

       Disable DoH use again by setting this option to NULL.

INHERIT OPTIONS
       DoH lookups use SSL and some SSL settings from your transfer are inher-
       ited, like CURLOPT_SSL_CTX_FUNCTION(3).

       The hostname and peer certificate verification settings are not  inher-
       ited but can be controlled separately via CURLOPT_DOH_SSL_VERIFYHOST(3)
       and CURLOPT_DOH_SSL_VERIFYPEER(3).

       A set CURLOPT_OPENSOCKETFUNCTION(3) callback is not inherited.

KNOWN BUGS
       Even when DoH is set to be used with this option, there are still  some
       name  resolves  that  are  performed without it, using the default name
       resolver mechanism. This includes name resolves done for CURLOPT_INTER-
       FACE(3),  CURLOPT_FTPPORT(3),  a  proxy type set to CURLPROXY_SOCKS4 or
       CURLPROXY_SOCKS5 and probably some more.

DEFAULT
       NULL - there is no default DoH URL. If this option is not set,  libcurl
       will use the default name resolver.

PROTOCOLS
       All

EXAMPLE
       CURL *curl = curl_easy_init();
       if(curl) {
         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
         curl_easy_setopt(curl, CURLOPT_DOH_URL, "https://dns.example.com");
         curl_easy_perform(curl);
       }

AVAILABILITY
       Added in 7.62.0

RETURN VALUE
       Returns  CURLE_OK on success or CURLE_OUT_OF_MEMORY if there was insuf-
       ficient heap space.

       Note that curl_easy_setopt(3) will  not  immediately  parse  the  given
       string  so when given a bad DoH URL, libcurl might not detect the prob-
       lem until it later tries to resolve a name with it.


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


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

SEE ALSO
       CURLOPT_VERBOSE(3), CURLOPT_RESOLVE(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                   May 04, 2022               CURLOPT_DOH_URL(3)