Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 07 Jun 2001 12:19:53 +0100
From:      Brian Somers <brian@Awfulhak.org>
To:        Poul-Henning Kamp <phk@critter.freebsd.dk>
Cc:        Brooks Davis <brooks@one-eyed-alien.net>, hackers@FreeBSD.ORG, brian@Awfulhak.org
Subject:   Re: cloning network interfaces 
Message-ID:  <200106071119.f57BJr766008@hak.lan.Awfulhak.org>
In-Reply-To: Message from Poul-Henning Kamp <phk@critter.freebsd.dk>  of "Wed, 06 Jun 2001 23:16:57 %2B0200." <85874.991862217@critter> 

next in thread | previous in thread | raw e-mail | index | archive | help
> In message <20010606141228.A13639@Odin.AC.HMC.Edu>, Brooks Davis writes:
> 
> >With network devices that are also normal devices the way tun is,
> >you do this by just implementing a dev_clone event handler so when the
> >user attempts to open a non-existent instance it's created.  The problem
> >with gif is that there's no device in /dev to open.  Since most network
> >devices at attached to hardware this usually doesn't matter, but in this
> >case it does.
> >
> >[...]
> >
> >How would this work anyway?
> >
> >Comments, thoughts, ideas?
> 
> The quick and dirty way:
> 
> 	Make a clone handler despite the fact that there is no /dev
> 	entry needed.  You don't actually have to create a dev entry
> 	in the clone handler, you could just create the gif_interface.
> 
> 	Applications would then:
> 
> 	stat("/dev/gif345") /* Ignore error */
> 	system("ifconfig gif345 bla bla bla");
> 
> The slower but less dirty:
> 
> 	Make a sysctl which returns an integer which is the next
> 	free gif device.
> 
> The really slow and very dirty:
> 
> 	Implement cloning in ifconfig.

Maybe a reasonable alternative would be to have a /dev/if_gif device 
with ioctls for creating and destroying interfaces.  ifconfig(8) 
could be taught to create (and maybe even to delete) them.

> -- 
> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
> phk@FreeBSD.ORG         | TCP/IP since RFC 956
> FreeBSD committer       | BSD since 4.3-tahoe    
> Never attribute to malice what can adequately be explained by incompetence.

-- 
Brian <brian@Awfulhak.org>                        <brian@[uk.]FreeBSD.org>
      <http://www.Awfulhak.org>;                   <brian@[uk.]OpenBSD.org>
Don't _EVER_ lose your sense of humour !



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200106071119.f57BJr766008>