From: Luis Ressel <aranea@aixah.de>
To: Torsten Krah <krah.tm@gmail.com>
Cc: wireguard@lists.zx2c4.com
Subject: Re: Endpoint address dns resolution - option to prefer IPv6 or IPv4
Date: Sat, 14 Mar 2020 16:52:28 +0000 [thread overview]
Message-ID: <20200314165228.jxydplbghnri2ktm@vega> (raw)
In-Reply-To: <327df26ff0e515425bc0b18084117b7ae065d97b.camel@gmail.com>
On Fri, Mar 13, 2020 at 03:52:19PM +0100, Torsten Krah wrote:
> I've got an endpoint with a DNS name which has both, an A and AAAA
> record.
> I would like to configure the client, so that I can tell him, to either
> prefer IPv6 or IPv4 for the vpn connection.
The relevant source code can be found here:
https://git.zx2c4.com/wireguard-tools/tree/src/config.c#n242
As you can see, wg resolves host names through the libc's getaddrinfo()
function, and simply uses the first ip address returned by that
function.
A standards-compliant implementation should return an ipv6 address in
the first position if one is available and the host has a working
connection to the v6 internet. As far as I know, both glibc and musl do
this (though the behaviour of glibc can be modified by editing
/etc/gai.conf); I'm not sure what other libcs do.
It would of course be possible to make this behaviour configurable for
wg; we just need to figure out if that's an useful feature, and what the
exact semantics should be.
Cheers,
Luis
next prev parent reply other threads:[~2020-03-14 16:52 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-13 14:52 Torsten Krah
2020-03-14 7:40 ` Stefan Tatschner
2020-03-14 14:53 ` Torsten Krah
[not found] ` <CAADpXXY7ajNwRoF1sivACxUfFj-SpWf6o6+1Uq2N0XzEp3bvTw@mail.gmail.com>
2020-03-14 14:51 ` Torsten Krah
2020-03-16 5:05 ` Roman Mamedov
2020-03-16 8:30 ` Torsten Krah
2020-03-14 16:52 ` Luis Ressel [this message]
2020-03-14 17:08 ` Matthias Urlichs
2020-03-14 18:03 ` Luis Ressel
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