From: Andi Kleen <ak@suse.de>
To: Wietse Venema <wietse@porcupine.org>
Cc: Andrey Savochkin <saw@saw.sw.com.sg>,
Matthias Andree <matthias.andree@gmx.de>, Andi Kleen <ak@suse.de>,
linux-kernel@vger.kernel.org
Subject: Re: notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias bug 2.4.9 and 2.2.19]
Date: Thu, 6 Sep 2001 19:03:49 +0200 [thread overview]
Message-ID: <20010906190349.A10470@gruyere.muc.suse.de> (raw)
In-Reply-To: <20010906204423.B23109@castle.nmd.msu.ru> <20010906165051.7EA29BC06C@spike.porcupine.org>
In-Reply-To: <20010906165051.7EA29BC06C@spike.porcupine.org>; from wietse@porcupine.org on Thu, Sep 06, 2001 at 12:50:51PM -0400
On Thu, Sep 06, 2001 at 12:50:51PM -0400, Wietse Venema wrote:
> That is not practical. Surely there is an API to find out if an IP
> address connects to the machine itself. If every UNIX system on
> this planet can do it, then surely Linux can do it.
It's not possible in the general case; e.g. it has to ignore NAT rules
and some of the more advanced features of policy routing
The API is rtnetlink. You can send a RTM_GETROUTE message and the kernel
will send you the routing entry for it; which has the RTN_LOCAL type for
local addresses.
> The same issue is true for local subnets. Surely there exists an
> API to find out what subnetworks a machine is attached to. If every
> UNIX system on this planet can do it, then surely Linux can do it.
You could resolve the backwards address using rtnetlink again and check
the resulting route for LINK scope. Again it is only an approximation
and will break in some/many cases.
-Andi
next prev parent reply other threads:[~2001-09-06 17:03 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20010905170037.A6473@emma1.emma.line.org.suse.lists.linux.kernel>
[not found] ` <20010905152738.C5912BC06D@spike.porcupine.org.suse.lists.linux.kernel>
[not found] ` <20010905182033.D3926@emma1.emma.line.org.suse.lists.linux.kernel>
2001-09-05 19:26 ` ioctl SIOCGIFNETMASK: ip alias bug 2.4.9 and 2.2.19 Andi Kleen
2001-09-06 13:11 ` Matthias Andree
2001-09-06 13:35 ` Andrey Savochkin
2001-09-06 14:04 ` Wietse Venema
2001-09-06 14:21 ` Matthias Andree
2001-09-06 15:37 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias bug 2.4.9 and 2.2.19] Andrey Savochkin
2001-09-06 15:58 ` Wietse Venema
2001-09-06 16:39 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias Alan Cox
2001-09-06 16:45 ` Wietse Venema
2001-09-06 16:44 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias bug 2.4.9 and 2.2.19] Andrey Savochkin
2001-09-06 16:47 ` Andi Kleen
2001-09-06 17:04 ` Andrey Savochkin
2001-09-06 16:50 ` Wietse Venema
2001-09-06 17:01 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias Alan Cox
2001-09-06 17:23 ` Wietse Venema
2001-09-06 17:45 ` Charles Cazabon
2001-09-06 19:34 ` Alan Cox
2001-09-06 19:41 ` Wietse Venema
2001-09-06 20:18 ` Alan Cox
2001-09-06 20:11 ` Matthias Andree
2001-09-06 20:23 ` Alan Cox
2001-09-06 20:31 ` Andi Kleen
2001-09-06 20:52 ` Matthias Andree
2001-09-07 9:06 ` Henning P. Schmiedehausen
2001-09-07 8:52 ` Matthew Kirkwood
2001-09-08 16:31 ` Wietse Venema
2001-09-06 18:11 ` Steve VanDevender
2001-09-06 18:25 ` Wietse Venema
2001-09-06 19:47 ` Alan Cox
2001-09-06 20:16 ` Wietse Venema
2001-09-06 19:10 ` Steve VanDevender
2001-09-13 14:35 ` Pavel Machek
2001-09-06 17:03 ` Andi Kleen [this message]
2001-09-06 17:23 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias bug 2.4.9 and 2.2.19] Andrey Savochkin
2001-09-06 17:39 ` Wietse Venema
2001-09-06 18:23 ` H. Peter Anvin
2001-09-07 1:47 ` Jamie Lokier
2001-09-07 5:48 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip aliasbug " Ben Greear
2001-09-07 5:50 ` H. Peter Anvin
2001-09-17 21:39 ` Ben Greear
2001-09-07 6:26 ` Andrey Savochkin
2001-09-07 6:21 ` H. Peter Anvin
2001-09-06 19:15 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias bug " dean gaudet
2001-09-06 19:33 ` Wietse Venema
2001-09-06 20:51 ` Matti Aarnio
2001-09-07 7:29 ` Andrey Savochkin
2001-09-07 7:35 ` Matthias Andree
2001-09-07 10:30 ` Mike Jagdis
2001-09-07 11:04 ` Matthias Andree
2001-09-07 15:34 ` Kurt Roeckx
2001-09-08 13:16 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias Kai Henningsen
2001-09-06 18:20 ` notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias bug 2.4.9 and 2.2.19] H. Peter Anvin
2001-09-06 16:01 ` Matthias Andree
2001-09-06 16:38 ` Andrey Savochkin
2001-09-06 16:43 ` Wietse Venema
2001-09-06 17:03 ` Charles Cazabon
2001-09-06 17:05 ` Alex Bligh - linux-kernel
2001-09-06 17:37 ` Andrey Savochkin
2001-09-06 17:55 ` kuznet
2001-09-06 14:51 ` ioctl SIOCGIFNETMASK: ip alias bug 2.4.9 and 2.2.19 Alan Cox
2001-09-06 14:17 ` Matthias Andree
2001-09-08 12:42 ` Kai Henningsen
2001-09-09 0:37 ` Matthias Andree
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