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Re: GSS API (as a DLL)...



>> System security things should be statically linked. Especially on
>> Suns, with their LD_PRELOAD functionality. The load library path
>> remains a vulnerability.

No it doesn't.  If the program runs as the user, then if I can spoof
your libraries, I can just as easily spoof ls as a "system security
thing".

If the program is setuid, then the dynamic loader should ignore
LD_LIBRARY_PATH if euid != ruid.  This is what SunOS (at least the
newer versions) does.

>> Of course you could counter with 'I am only going to allow the
>> authentication methods listed in this file', but then there is no
>> advantage in dynamic linking over runtime linking, and very little
>> over static linking.

This is *exactly* what I would say. The advantages over static linking
are clear: you don't have to do it when you get a new security
mechanism.  Dynamic linking also requires you recompile if you want to
add new mechanisms, as the dynamic linking systems I'm familiar with
assume one symbol space; if you have two libraries with the same
function names, you can't use both at the same time.

Now that I've said that, I'll be a hypocrite.  This is www-security,
not random-os-security.  There are other lists for that.

		Marc




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