Displaying streams as xattrs

[Steve French]

We do allow querying ads now from user space for cifs.ko. was wondering if
xattr emulation for them like macs apparently do would also help

On Mon, May 22, 2023, 07:42 ronnie sahlberg <ronniesahlberg at gmail.com>
wrote:

> We want to expose ADS to the applications?
> Maybe FCNTL is a better interface to do this than magix xattrs.
> An application could open a file, and then use fcntl to
> list/open/create/delete streams?
>
> We should talk to the NTFS maintainers too as this is an ntfs feature
> and they might alwo want to expose ADS to apps.
> So we get a solution that we can use across multiple filesystems.
>
> regards
> ronnie s
>
>
>
> On Mon, 22 May 2023 at 16:40, Steve French <smfrench at gmail.com> wrote:
> >
> > On Sun, May 21, 2023 at 11:33 PM ronnie sahlberg
> > <ronniesahlberg at gmail.com> wrote:
> > >
> > > A problem  we have with xattrs today is that we use EAs and these are
> > > case insensitive.
> > > Even worse I think windows may also convert the names to uppercase :-(
> > > And there is no way to change it in the registry :-(
> >
> > But for alternate data streams if we allowed them to be retrieved via
> xattrs,
> > would case sensitivity matter?  Alternate data streams IIRC are already
> > case preserving.   Presumably the more common case is for a Linux user
> > to read (or backup) an existing alternate data stream (which are usually
> > created by Windows so case sensitivity would not be relevant).
> >
> > > On Mon, 22 May 2023 at 12:09, Steve French via samba-technical
> > > <samba-technical at lists.samba.org> wrote:
> > > >
> > > > Looking through code today (in fs/cifs/xattr.c) I noticed an old
> > > > reference to returning alternate data streams as pseudo-xattrs.
> > > > Although it is possible to list streams via "smbinfo filestreaminfo"
> > > > presumably it is not common (opening streams on remote files from
> > > > Linux is probably not done as commonly as it should be as well).
> > > >
> > > > Any thoughts about returning alternate data streams via
> pseudo-xattrs?
> > > > Macs apparently allow this (see e.g.
> > > >
> https://www.jankyrobotsecurity.com/2018/07/24/accessing-alternate-data-streams-from-a-mac/
> )
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Thanks,
> > > >
> > > > Steve
> > > >
> >
> >
> >
> > --
> > Thanks,
> >
> > Steve
>