Subject: Re: [PATCH 2/3] Avoid reverse resolution for server name
From: Simo Sorce <simo@redhat.com>
To: Steve Dickson <SteveD@redhat.com>
Cc: "Myklebust, Trond" <Trond.Myklebust@netapp.com>,
        Linux NFS Mailing list <linux-nfs@vger.kernel.org>
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Date: Tue, 02 Apr 2013 14:44:17 -0400
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On Tue, 2013-04-02 at 14:25 -0400, Steve Dickson wrote:
> 
> On 02/04/13 14:21, Simo Sorce wrote:
> > On Tue, 2013-04-02 at 17:58 +0000, Myklebust, Trond wrote:
> >>> -----Original Message-----
> >>> From: linux-nfs-owner@vger.kernel.org [mailto:linux-nfs-
> >>> owner@vger.kernel.org] On Behalf Of Simo Sorce
> >>> Sent: Tuesday, April 02, 2013 1:49 PM
> >>> To: Linux NFS Mailing list
> >>> Subject: [PATCH 2/3] Avoid reverse resolution for server name
> >>>
> >>> A NFS client should be able to work properly even if the DNS Reverse record
> >>> for the server is not set. There is no excuse to forcefully prevent that from
> >>> working when it can.
> >>
> >> Note that rpc.statd has the same limitation.
> > 
> > I checked rpc.statd with a quick "git grep getnameinfo", and as far as I
> > can see PTR lookups are done only if the 'name' is actually an IP
> > address, but skipped if not. So I think rpc.statd is ok.
> > 
> > I see rpc.statd uses getaddrinfo with hints set to AI_NUMERICHOST, if
> > that's preferred over using inet_pton I can change my patches to do the
> > same.
> Please do.. let try to keep it consistent.... thanks!

Ok I looked at doing it, and looked at a helper function to reuse to
avoid duplication, however the functions in statd/hostname.c are static,
then I looked ad host_pton in support/export/hostname.c and realized 2
things:
- the comments there say inet_pton is actually better for what I need to
do, in fact inet_pton is used as a filter before calling getaddrinfo.
- the function can't be used in gssd_proc.c as the file is not linked
there.

So given the above I would prefer to not change the use of inet_pton in
the patches and leave them as is.

Simo.

-- 
Simo Sorce * Red Hat, Inc * New York