Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.debian.user > #227135

Re: Two questions about LUKS in a file container

Show all headers | View raw

On 2020-09-19 07:57, David Wright wrote:
> On Thu 17 Sep 2020 at 13:32:16 (-0700), David Christensen wrote:
>> On 2020-09-16 14:38, David Wright wrote:
>>> On Wed 16 Sep 2020 at 12:56:36 (-0700), David Christensen wrote:
>>>> On 2020-09-16 01:59, Andrei POPESCU wrote:
>>
>>>> If I change the mode of the mount point to 0000:
>>
>>>> Is there some advantage other than making a long listing visually
>>>> distinctive when the mount point is not in use?
>>>
>>> Yes. As explained earlier in the thread, it prevents user OP from
>>> accidentally scribbling in the unused mountpoint.
>>
>> The default permissions 0755 already do that:
>>
>> 2020-09-17 13:21:22 dpchrist@tinkywinky ~
>> $ touch /f1/foo
>> touch: cannot touch '/f1/foo': Permission denied
> 
> Only because root created the mount point, as root would have to do
> for a mount point in /.
> 
> The blog example uses $HOME/Private/ which would, with a typical
> user's umask, be writeable by the user.

2020-09-19 13:20:00 dpchrist@tinkywinky ~
$ cat /etc/debian_version ; uname -a
9.13
Linux tinkywinky 4.9.0-13-amd64 #1 SMP Debian 4.9.228-1 (2020-07-05) 
x86_64 GNU/Linux

2020-09-19 13:24:20 dpchrist@tinkywinky ~
$ mkdir mountpoint

2020-09-19 13:24:24 dpchrist@tinkywinky ~
$ touch mountpoint/foo

2020-09-19 13:24:28 dpchrist@tinkywinky ~
$ chmod 0000 mountpoint

2020-09-19 13:24:37 dpchrist@tinkywinky ~
$ touch mountpoint/bar
touch: cannot touch 'mountpoint/bar': Permission denied


Okay.  I can see how that might alert me if I attempt to write to a 
mountpoint that is not active.


> ... I was hoping you might have cracked how to mount a fuse
> filesystem as a user, as described in:
> 
>      What is FUSE?
>      ~~~~~~~~~~~~~
> 
>      FUSE is a userspace filesystem framework. […]
> 
>      One of the most important features of FUSE is allowing secure,
>      non-privileged mounts.  This opens up new possibilities for the use of
>      filesystems.  A good example is sshfs: a secure network filesystem
>      using the sftp protocol.
> 
>      https://www.kernel.org/doc/Documentation/filesystems/fuse.txt
> 
> But with my experiments (on exFAT), I couldn't get past what looks
> like #916987:
> 
> $ mount /media/cruzer4g/
> FUSE exfat 1.3.0
> fusermount: unknown option 'user=david'
> $
> 
> That was after adding   user_allow_other   to /etc/fuse.conf (which
> I didn't want) to get past:
> 
> $ mount /media/cruzer4g/
> FUSE exfat 1.3.0
> fusermount: option allow_other only allowed if 'user_allow_other' is set in /etc/fuse.conf
> $
> 
> … and after being taking ownership of both mount point and device file.
> 
> So I'm mounting with sudo, and appending    ,umask=077,uid=1000,gid=1000
> to the fstab entry to gain user access to the filesystem.
> 
> Do you know if fuse exFAT is a stopgap, and support in the kernel is
> eventually coming, or was a fuse implementation necessarily chosen
> to support exFAT on account of some particular problem. It seems odd
> that pmount, for example, doesn't support exFAT (which would seem
> a prime candidate).
> 
> The fuse documentation is so fragmentary, scattered and sparse that
> I haven't really got a good feel for what is is or how it works.
> I'm always thinking that I've missed some option or other that allows
> it to work as I expected it to.

2020-09-19 14:04:40 dpchrist@tinkywinky ~
$ apt-cache search fuse | grep FAT
exfat-fuse - read and write exFAT driver for FUSE
fusefat - File System in User Space - Module for FAT
umview-mod-umfusefat - View-OS in user space - FAT module for UMFUSE


Have you tried exfat-fuse or fusefat?


David

Back to linux.debian.user | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Two questions about LUKS in a file container rhkramer@gmail.com - 2020-09-12 18:20 +0200
  Re: Two questions about LUKS in a file container Hans <hans.ullrich@loop.de> - 2020-09-12 18:50 +0200
  Re: Two questions about LUKS in a file container Bob Weber <bobrweber@gmail.com> - 2020-09-12 21:10 +0200
    Re: Two questions about LUKS in a file container Andrei POPESCU <andreimpopescu@gmail.com> - 2020-09-16 11:00 +0200
      Re: Two questions about LUKS in a file container David Christensen <dpchrist@holgerdanske.com> - 2020-09-16 22:00 +0200
        Re: Two questions about LUKS in a file container David Wright <deblis@lionunicorn.co.uk> - 2020-09-16 23:40 +0200
          Re: Two questions about LUKS in a file container David Christensen <dpchrist@holgerdanske.com> - 2020-09-17 22:40 +0200
            Re: Two questions about LUKS in a file container David Wright <deblis@lionunicorn.co.uk> - 2020-09-19 17:00 +0200
              Re: Two questions about LUKS in a file container David Christensen <dpchrist@holgerdanske.com> - 2020-09-19 23:10 +0200
              Re: Two questions about LUKS in a file container Andrei POPESCU <andreimpopescu@gmail.com> - 2020-09-21 08:00 +0200
                Re: Two questions about LUKS in a file container David Wright <deblis@lionunicorn.co.uk> - 2020-09-21 16:30 +0200
  Re: Two questions about LUKS in a file container Charles Curley <charlescurley@charlescurley.com> - 2020-09-12 21:40 +0200
    Re: Two questions about LUKS in a file container David Christensen <dpchrist@holgerdanske.com> - 2020-09-13 01:00 +0200
  Re: Two questions about LUKS in a file container David Christensen <dpchrist@holgerdanske.com> - 2020-09-13 00:20 +0200
    Re: Two questions about LUKS in a file container rhkramer@gmail.com - 2020-09-13 02:10 +0200
  Re: Two questions about LUKS in a file container David Wright <deblis@lionunicorn.co.uk> - 2020-09-13 17:20 +0200
    Re: Two questions about LUKS in a file container David <bouncingcats@gmail.com> - 2020-09-13 17:30 +0200

csiph-web