Global Preferences - Lua sandbox DLL checkbox

What exactly does the "Allow DLLs to be loaded" checkbox do? I don't see much difference between checking and unchecking it; no matter what state it's in, I still need to trust my world (as well as plugin if I'm in one of those) to use loadlib().

While I'm on this topic, it seems to me like Lua is the only language limited from loading DLLs by default. Is that correct?

If that is not checked, after MUSHclient loads Lua, it sets package.loadlib to be nil, so you can't use it to load DLLs.

It also sets:



These are used by the "require" function. See:

http://www.gammon.com.au/scripts/doc.php?lua=package.loaders

The overall intention was to stop malicious use of DLLs without user authorization.

I can't speak for how secure all the other languages are, my intention was not to open gaping security holes by allowing things like io (which could delete or open files), or DLLs (which could be used to load arbitrary code) without at least some user knowledge or intervention.

You know how Microsoft has been sledged over the years for making an insecure product? In many ways, this insecurity comes about because they tried to make it easy for the end-user, so they didn't put too many restrictions into their products. Of course, those insecurities ended up being exploited, with the end-result that we now have worms, viruses, trojans, and everything else under the sun lurking in Windows computers.

After fiddling with it a bit more, it looks like no matter what the 'trusted' status of a plugin or world is, the checkbox controls the usability of the bits you mentioned above. Guess that's what it does. *laughs* My initial experimenting wasn't extensive enough it seems.


Less on topic: I completely agree on the security issues. It just seems to me like it's more difficult than warranted to load external libraries. I think a better interface, like a Triggers/Aliases-esque list, might make it easier on users, while still ensuring they know what they're getting into... EDIT: i.e. you could add entries for the worlds/plugins that should be given various degrees of access, and specifically trusted plugins should not be dependent on their world also being trusted.