Re: [Haskell-cafe] "back doors" into the IO monad

On 23/10/10 23:28, Manlio Perillo wrote:

Hi.

What are the available methods to execute IO actions from pure code?

I know only unsafePerformIO and foreign import (to call a non pure foreign function).

Assuming I want to execute external untrusted code using plugins (via the `plugins` package), is it possible to completely forbid execution of IO actions from user code?

Even pure code can cause denial of service through huge memory consumption or infinite loop. Perhaps it would be wise to look at how 'lambdabot'/'mueval' work, using OS-level security limits to restrict amount of memory and time that can be used by untrusted code (which already has had its IO priviledges revoked, see their source codes for details).

Thanks Manlio

Claude