[Samba] Linux & NFSv4 ACLs

[Jeremy Allison]

On Fri, Dec 04, 2015 at 01:37:33PM -0700, Nick Couchman wrote:
> ----- Original Message -----
> > From: "Jeremy Allison" <jra at samba.org>
> > To: "Nick E Couchman" <nick.couchman at seakr.com>
> > Cc: samba at lists.samba.org
> > Sent: Friday, December 4, 2015 1:22:06 PM
> > Subject: Re: [Samba] Linux & NFSv4 ACLs
> 
> > On Thu, Dec 03, 2015 at 07:31:36PM -0700, Nick Couchman wrote:
> >> 
> >> Try these pages (U Michigan):
> >> http://www.citi.umich.edu/projects/nfsv4/linux/nfs4-acl-tools/
> >> http://www.citi.umich.edu/projects/nfsv4/linux/
> >> 
> >> and here:
> >> http://wiki.linux-nfs.org/wiki/index.php/ACLs
> >> 
> >> I'm pretty sure that first link is the source that the RHEL/CentOS tools comes
> >> from.  Here's output from YUM on CentOS
> >> 
> >> [root at snapshots ~]# yum whatprovies *bin/nfs4_getfacl
> >> Loaded plugins: fastestmirror
> >> No such command: whatprovies. Please use /usr/bin/yum --help
> >> [root at snapshots ~]# yum whatprovides *bin/nfs4_getfacl
> >> Loaded plugins: fastestmirror
> >> Loading mirror speeds from cached hostfile
> >>  * extras: linux.mirrors.es.net
> >> nfs4-acl-tools-0.3.3-13.el7.x86_64 : The nfs4 ACL tools
> >> Repo        : base
> >> Matched from:
> >> Filename    : /usr/bin/nfs4_getfacl
> > 
> > Thanks for that. The problem is /usr/bin/nfs4_getfacl
> > uses an internal library to get marshall/unmarshall the
> > ACL data into EA's. I don't think that library is
> > installed (and there's no nfs4_acl-dev package).
> 
> If I do a "ldd /usr/bin/nfs4_getfacl" here are the results:
> [root at pv-nas ~]# ldd `which nfs4_getfacl`
> 	linux-vdso.so.1 =>  (0x00007fffa76f6000)
> 	libattr.so.1 => /lib64/libattr.so.1 (0x00007ffe77f2c000)
> 	libc.so.6 => /lib64/libc.so.6 (0x00007ffe77b98000)
> 	/lib64/ld-linux-x86-64.so.2 (0x00007ffe7833d000)
> 
> 
> So, I don't see any shared library specifically for NFSv4 stuff, just the libattr dependency.  I'm guessing this is what you mean - that there isn't a shared library available with an API you could use in a Samba VFS module to abstract the calls for getting/setting the NFSv4 ACLs - you'd have to actually write the entire library inside the VFS module?

Yep, that's exactly is. Internal to nfs4_getfacl
source there's libnfs4acl/, which does what we need,
but it doesn't get installed by 'make install'.