How to view set-user-ID and set-group-ID

Xris718 · 01-09-2004, 01:36 PM

Hi guys

I have question. How can I view files with set-user-ID and set-group-ID. For example when i do this:

ls -l
-rw-r--r-- 1 102 adm 1660656 Jan 27 2003 file_name

but this does not show me what set-user-ID or set-group-ID or sticky bit for this particular file or any files for that matter. It only gives me permissions for it. How can I view set-user-ID or set-group-ID or sticky bit ?

I have been reading man on ls and chmod and couldnt find anything in man pages. Searched online but was unsuccessful. Any help would be appreciated.

Tinkster · 01-09-2004, 02:45 PM

Quote:

but this does not show me what set-user-ID or set-group-ID or sticky bit for this particular file or any files for that matter. It only gives me permissions for it.

Well, this might be because there are none?
Usually you'll only see SUID/SGID on executalbes,
in the first place ...
Have a look at

ls -l /usr/sbin

You'll probably find a few that look like

Code:

-r-xr-sr-x    1 root     smmsp      519864 Jun  5  2002 sendmail
-r-sr-xr-x    1 root     root        15848 Feb 21  2003 unix_chkpwd

Note the s instead of the x? :)

Cheers,
Tink

Xris718 · 01-09-2004, 08:40 PM

So what does that mean "s" instead of an "x" ? whats "s" stand for ? and does it only show up in executable files?

fr0zen · 01-09-2004, 09:13 PM

's' implies the set sticky-bit. The location of the 's' determines whether it sets the UID or GID.

It only applies to files that have execution capabilities. This is not limited to binary files, but scripts as well.

Xris718 · 01-09-2004, 09:23 PM

Cool thanks for info... Another question what is the difference between 4700 and 700 permissions ?

fr0zen · 01-09-2004, 11:44 PM

The difference is that 4700 sets the stick-bit for SUID, whereas 700 merely enables read, write and execute for just the owner of the file.

4700 is a rather pointless combination, as it defeats the purpose of the SUID sticky-bit. If you were to chmod something to 4700, only the owner of the file would be able to execute it. Then, the program would be SUID to that user. Since the prerequisite for execution (or read and write even) is that you be the owner of the file, seems like you're doing more work than you really need.

Xris718 · 01-10-2004, 12:49 PM

Thanks for info ... more questions

How about 4750 vs 750 .... What is the difference between this?

Tinkster · 01-10-2004, 01:44 PM

Same as above. Just that in this case the owner can
edit it, too, while the the group can only read and
execute, and other can do diddly-squat.

Try
man 2 chmod
, this is getting tiring...

Cheers,
Tink