netdev - Re: [PATCH 2/2] IPVS: Add genetlink interface implementation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 11 Jul 2008 01:16:44 +0200
From:	"Julius Volz" <juliusv@...gle.com>
To:	"Thomas Graf" <tgraf@...g.ch>
Cc:	"Patrick McHardy" <kaber@...sh.net>, netdev@...r.kernel.org,
	lvs-devel@...r.kernel.org, vbusam@...gle.com, horms@...ge.net.au,
	davem@...emloft.net
Subject: Re: [PATCH 2/2] IPVS: Add genetlink interface implementation

On Thu, Jul 10, 2008, Thomas Graf wrote:
> Personally I would never use a GET id to send any data at all. My main
> focus is on trying to make message protocols self documenting. If a
> certain message type has multiple meanings depending on the direction
> it will make it harder to understand and harder to debug from a protocol
> standpoint.

Makes sense so far, but:

> The common netlink semantics are
>
>  CMD_OBJ_NEW - create or update objects as described in the message
>               content.

If a single operation just means create _or_ update (NLM_F_EXCL, etc.
flags don't work with genetlink), then ipvsadm would have to query for
an entry first, which is racy and ugly. So I'd like to keep ADD/EDIT
in separate commands. But then I need a different response id (or just
use the ADD id?) for a GET.

>  CMD_OBJ_SET - rarely used, update a static object which doesn't have
>               to be created or added. asme as OBJ_NEW otherwise.

Like in the case of sending the GET_INFO or GET_TIMEOUT replies.

>  CMD_OBJ_DEL - delete object described in the message
>  CMD_OBJ_GET - search for a object as described in the message and
>               send a CMD_OBJ_NEW as reply including the full object.
>
>               with NLM_F_DUMP: iterate over all objects and send a
>               CMD_OBJ_NEW for each object. This request often carries
>               no additional data.

Ok, that makes sense too and is pretty much what I have.

Julius

-- 
Google Switzerland GmbH
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html