From: Vitaliy Makkoveev <otto@bsdbox.dev>
Subject: Re: tun(4): SIOCSIFDSTADDR is deprecated, so stop handling it
To: Claudio Jeker <cjeker@diehard.n-r-g.com>
Cc: David Gwynne <david@gwynne.id.au>, tech@openbsd.org
Date: Sat, 19 Oct 2024 12:45:30 +0300

> On 19 Oct 2024, at 11:45, Claudio Jeker <cjeker@diehard.n-r-g.com> wrote:
> 
> On Tue, Oct 15, 2024 at 01:33:46PM +1000, David Gwynne wrote:
>> according to netintro, SIOCSIFDSTADDR is deprecated. only a handful of
>> old drivers still have code to handle it, so i'd like to clean them up.
>> tun(4) can go first.
>> 
>> ok?
>> 
>> Index: if_tun.c
>> ===================================================================
>> RCS file: /cvs/src/sys/net/if_tun.c,v
>> diff -u -p -r1.241 if_tun.c
>> --- if_tun.c	10 Oct 2024 06:50:58 -0000	1.241
>> +++ if_tun.c	15 Oct 2024 03:29:35 -0000
>> @@ -599,10 +543,6 @@ tun_ioctl(struct ifnet *ifp, u_long cmd,
>> 			CLR(ifp->if_flags, IFF_RUNNING);
>> 		break;
>> 
>> -	case SIOCSIFDSTADDR:
>> -		tun_init(sc);
>> -		TUNDEBUG(("%s: destination address set\n", ifp->if_xname));
>> -		break;
>> 	case SIOCSIFMTU:
>> 		if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > TUNMRU)
>> 			error = EINVAL;
>> 
> 
> I think this is not correct. You still want to be able to use the
> SIOCSIFDSTADDR ioctl. An example for this is
> regress/sbin/ifconfig/ifaddr.c.
> I think this should just do:
> 
> 	case SIOCSIFDSTADDR:
> 		break;
> 
> This way there is no error when SIOCSIFDSTADDR is used.
> 
> -- 
> :wq Claudio
> 

Isn’t it better to adjust regress test? SIOCSIFDSTADDR is not appropriate
for tun(4) interfaces.