Messages in this thread | | | Date | Fri, 27 Nov 1998 20:47:33 +0100 (MET) | From | Clifford Wolf <> | Subject | Re: High UID support for Linux |
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On Fri, 27 Nov 1998, Matti Aarnio wrote:
> pjb1008@cam.ac.uk (Peter Benie) wrote: > > Matti Aarnio writes ("Re: High UID support for Linux"): > > > > That's why I want 16 bit uid to 32 bit uids to be a planned change, > > > > rather than for it to be flag day for Linux where everyone has to > > > > throw away all their existing code. > > > > > > If your runtime environment has only 16-bit UIDs, use of > > > old binaries via old syscalls will continue as before > > > *without any changes*. > > > > I don't see why I should have to recompile code for programs that > > aren't interested in uids, but happen to use them purely because > > braindamaged Unix APIs. > > There are two issues: > - the way how KERNEL represents the values (e.g. 16-bit uids) > - the way how LIBRARY represents the values (e.g. 32-bit uids) > > The glibc-2.0.7-19 at i386 has 32-bit unsigned integers as uids. > It hides the __kernel_uid_t from the user. > > This means: > We can *any day* change kernel to support 32-bit uids > at i386 (with new kernel syscalls) as long as we do > remember to write matching interface routines for the > glibc so that it can take full advantage of the result.
Hi gang, here are my 0.02 euros to this topic:
So why don't we note to move this 32-bits <-> 16-bits transaltion into the kernel as one of the first 2.3.x issues? I don't think that it would be that hard to do this - it's just to late for such a change before 2.2.0.
After this is done we could write function to translate 32-bit-uids to 16-bit-uids. This function could check for uids higher than 32767 (or 65535?) and converts them to 'nobody' and prints a kernel warning (could this behavor result in security problem?).
As soon as this framework is done we could migrate step-by-step to 32-bit-uids without breaking any user-level interface anymore.
The only hard thing (tm) will be the filesystems ....
keep hacking, clifford
-- -- -- -- -- -- -- -- -- -- -- -- -- Clifford Wolf (CEO and CTO) The ROCK Projects Workgoup IRC: IRCnet / clifford http://www.rock-projects.com/ http://www.clifford.at/ e-mail: c.wolf@rock-projects.com email: god@clifford.at
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