Return-Path: Received: from fieldses.org ([173.255.197.46]:49932 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729393AbeHVSha (ORCPT ); Wed, 22 Aug 2018 14:37:30 -0400 Date: Wed, 22 Aug 2018 11:12:13 -0400 From: "J. Bruce Fields" To: "Paul B. Henson" Cc: linux-nfs@vger.kernel.org Subject: Re: nfs4-acl-tools 0.3.5 Message-ID: <20180822151213.GA24172@fieldses.org> References: <20180807193736.GA18187@fieldses.org> <20180821165130.GA14413@fieldses.org> <5fa4b700-3d45-cda3-37ed-bdfbd427574d@acm.org> <20180822003301.GA17500@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue, Aug 21, 2018 at 06:18:49PM -0700, Paul B. Henson wrote: > On 8/21/2018 5:33 PM, J. Bruce Fields wrote: > > >In the wire protocol there's no need for such constants. An ACE can > >have one of the special strings OWNER@, GROUP@, or EVERYONE@ in the > >owner field, and that's all you need. > > Ah, so an NFSv4 client is supposed to figure out whether or not it's > a special ACE just by the who_string... That probably explains why I > didn't see the same issue using the nfs4-acl-tools on a Linux client > mounting an illumos ZFS share via NFS. > > >The only use of those constants is probably internal to the ACL tools, > >so they don't have to agree with any standards. > > Ok, I found the illumos NFSv4 server code where it converts the > local ZFS ACLs to/from xdr format, and you're right, those flags are > not included in the outbound mapping, it converts them to the > special entry strings, and it does string comparisons to determine > whether or not to add them for the inbound mapping. > > However, in the nfs4-acl-tools code it seems to expect those bits > off the wire to decode and is willing to send them on the wire? > > For example, in libnfs4acl/nfs4_get_ace_flags.c > > if (flags & NFS4_ACE_OWNER) > *buf++ = FLAG_OWNER_AT; > > If it sees that bit set in the flags, it adds 'O' to the string > representation, and correspondingly in > libnfs4acl/nfs4_ace_from_string.c: > > case FLAG_OWNER_AT: > flags |= NFS4_ACE_OWNER; > break; Huh. Yeah, that does look like a bug. But I'm surprised the utilities would work at all in that case--I'd expect both the Solaris and Linux knfsd to reject an ACL with those extra bits, and certainly neither would set them on read. So I can't help thinking I'm overlooking some sanitization of the flags field somewhere..... Time to test and look at the wire traffic in wireshark, I guess. > If you include O in your ACL specification, it will add that flag > and include it when it sends it? The same for the NFS4_ACE_GROUP and > NFS4_ACE_EVERYONE flags. > > I'm confused why the nfs4-acl-tools would need these local defines. > On the ZFS side, the on-disk ACL format doesn't include strings, > just flags and uids/gids, so the extra flag bits are presumably > needed so it can tell which entries are special. However, the tools > presumably are only intended to consume NFSv4 xdr, and generate it? > So why did they need these flags given that the NFSv4 xdr format > doesn't include them? I suspect they're unnecessary, and I'd happily take a patch to remove them once we figure out what's going on. --b.