Problem: DOSEMU ignores Linux user file access settings

Problem: DOSEMU ignores Linux user file access settings

[Mgr. Peter Tuharsky]

    Hallo!

    I have big problem with file access privilegues. I don't know how to 
solve it. Or how to force DOSEMU to respect Linux file access settings?

    DOSEMU uses one strict policy when creating new file from inside 
emulated environment: It creates new file with 600 attrib mask and 
user-only gid/uid. DOSEMU fully IGNORES both bash.profile setting, and 
folder's SetUid/SetGid setting!! And this is the reason of my big problem.

    I have DOSEMU 1.2rc1 installed on the one machine (server) and 
second computer is connected as thin client, so the DOSEMU runs only 
locally on the server, on local drive, local directory on Linux 
filesystem to avoid any network-drive related problems (elegant 
solution, there isn't difference between "tru local" and "remote X" 
session -both are in fact local on server).

    I need two users to run simultaneously one copy of Clipper database 
program. If I manually add both users to the same workgroup (name it 
'ambul') and set group attribute of the files and folders they should 
have access, and set correct attributes (770), the program runs smoothly 
(expecting the sometimes slow feeling because of that stupid "what's the 
time?" loop typical for Clipper). As long as they work with only 
existing files with correct attributes set, it works perfectly.
    But once the program creates new file under one user's session (what 
sometimes happens during some actions such as print or so), the program 
in second user's session claims error opening the file and crashes. The 
same when reindexing the database (it creates new .ntx files with the 
crippled privilegues too). It dosen't matter, which one is the "first" 
user. The program under the first session creates a new file and DOSEMU 
gives the file 600 (rw user-only) permissions, no matter that 
bash.profile says that user's new files must be created with 770 mask 
(rwxrwx---), and the folder has SetGid attribute set, so that all 
created files should have Group attribute set to the same value as the 
parent directory has.

    My first approach was to search for some setting in .dosemurc to do 
this, but I cannot find such setting that would force DOSEMU to respect 
Linux file access rights management when creating new file.

    Thent I thought that logging the both sessions under the same 
username could solve the problem. Not good solution, but better than 
nothing. This cannot work, however. Both users want to print to their 
printers, and the printers are defined thru .dosemurc files in their 
home directories. Once I run both users under the same login name, they 
both use the same .dosemurc settings file and thus BOTH PRINT ON THE 
SAME NETWORK PRINTER! Running one of DOSEMU session from other home 
directory dosen't help either, because DOSEMU takes .dosemurc strictly 
from user's home directory and this way the printing is directed to only 
one printer.


    Please hlep. How to force DOSEMU to respect Linux file access 
management?

          Sincerely
             Peter

Re: Problem: DOSEMU ignores Linux user file access settings

[Bartos-Elekes Zsolt]

> Both users want to print to their 
> printers, and the printers are defined thru .dosemurc files in their 
> home directories. Once I run both users under the same login name, they 
> both use the same .dosemurc settings file and thus BOTH PRINT ON THE 
> SAME NETWORK PRINTER! Running one of DOSEMU session from other home 
> directory dosen't help either, because DOSEMU takes .dosemurc strictly 
> from user's home directory and this way the printing is directed to only 
> one printer.

See the -f parameter for dosemu.bin to use a different .dosemurc, and start 
each dosemu client with a different .dosemurc, which contains only a line like
$_printer = "rlp_1"

Sincerely,
Zsolt

Re: Problem: DOSEMU ignores Linux user file access settings

[Bart Oldeman]

On Mon, 19 Jan 2004, Mgr. Peter Tuharsky wrote:

>     DOSEMU uses one strict policy when creating new file from inside
> emulated environment: It creates new file with 600 attrib mask and
> user-only gid/uid. DOSEMU fully IGNORES both bash.profile setting, and
> folder's SetUid/SetGid setting!! And this is the reason of my big problem.

no, DOSEMU doesn't ignore them. Be careful here. What is your umask
setting from bash.profile? Try a simple
umask
to be sure about that (in Linux)

If it's 007 then new DOSEMU files (with archive bit set) are
normally created as
-rw-rw----

Also DOSEMU doesn't do chown on files so I can't see how it could ignore
setgid attributes on directories -- the files will have the same
owner/group as a simple file created with
echo hello > file
would do. Try this command in Linux *and* in DOSEMU in the same
directory and look at the permissions.

> directory dosen't help either, because DOSEMU takes .dosemurc strictly
> from user's home directory and this way the printing is directed to only
> one printer.

Try -f. Also the environment variable dosemu__printer can do the trick as
long as you do *not* define it in .dosemurc.

Bart

Re: Problem: DOSEMU ignores Linux user file access settings -solved

[Mgr. Peter Tuharsky]

Thank You very much.

I tested the way You suggested and I figured out that fault was mine. 
Maybe it was matter of too much stress :o)

The bash.profile umask was set ok, but when I ran DOSEMU directly from X 
and not from terminal, the bash.profile was of course not interpreted. 
Solution was quite simple -add umask command to dosemu start script.

Your help was valuable cause I was able to find and solve problem thanks 
to Your advice.

Thanks to You all that answered my question. Also thanks to DOSEMU team 
for their great work!

Sincerely Peter


Bart Oldeman wrote:

>On Mon, 19 Jan 2004, Mgr. Peter Tuharsky wrote:
>
>  
>
>>    DOSEMU uses one strict policy when creating new file from inside
>>emulated environment: It creates new file with 600 attrib mask and
>>user-only gid/uid. DOSEMU fully IGNORES both bash.profile setting, and
>>folder's SetUid/SetGid setting!! And this is the reason of my big problem.
>>    
>>
>
>no, DOSEMU doesn't ignore them. Be careful here. What is your umask
>setting from bash.profile? Try a simple
>umask
>to be sure about that (in Linux)
>
>If it's 007 then new DOSEMU files (with archive bit set) are
>normally created as
>-rw-rw----
>
>Also DOSEMU doesn't do chown on files so I can't see how it could ignore
>setgid attributes on directories -- the files will have the same
>owner/group as a simple file created with
>echo hello > file
>would do. Try this command in Linux *and* in DOSEMU in the same
>directory and look at the permissions.
>
>  
>
>>directory dosen't help either, because DOSEMU takes .dosemurc strictly
>>from user's home directory and this way the printing is directed to only
>>one printer.
>>    
>>
>
>Try -f. Also the environment variable dosemu__printer can do the trick as
>long as you do *not* define it in .dosemurc.
>
>Bart
>
>  
>