> -----Original Message----- > From: Eli Barzilay [mailto:e...@barzilay.org] > Sent: 28 June 2011 13:56 > To: Jukka Tuominen > Cc: Sam Tobin-Hochstadt; users@racket-lang.org > Subject: RE: [racket] Limiting net-repl provided functions > > > Three hours ago, Jukka Tuominen wrote: > > > > Thanks Eli, much appreciated! > > > > By means of just limiting provided functions, the latter approach > > seems bullet-proof (although lacking sandbox characteristics that > > net-repl partly does already AFAIU). > > > > If however, I would choose the sandbox approach, can you think of > > any way to break into the system by utilizing some 'invisible' > > features? Is this also bullet-proof? > > The sandbox is more proof in a sense that it requires explicit > permission for things like FS access or taking too long, or using a > lot of memory. For example, if your `f1' handler happens to consume > too much memory, running it inside the sandbox will lead to an > exception rather than to crashing the server. Worse, your handlers > might be open to code injection that you didn't anticipate. So it can > basically protect you against bugs in your own code. > > But if you trust your code to be safe, then the explicit dispatching > is overall simpler to deal with.
Ok, I see. In a way both are needed but for different purposes... which of cource adds to the number of moving parts. At the moment, I'm advancing with the sandbox approach. > > > An hour and a half ago, Jukka Tuominen wrote: > > > > this works nicely in Linux (where intented), but when tested inside > > Win XP/ Racket 5.1., it gives the following error: > > > > file-exists?: `exists' access denied for C:\Program > > Files\Racket\lib\libeay32.dll > > A sandbox requires explicit permission to access any file (and with > different kind of access). > > But the default should allow reading files in the racket tree, so this > might be a bug. After adding some more modules to the test case, also Linux/ R 5.1 gave the same error, except for the path: /usr/lib/racket/libcrypto.so br, jukka > > -- > ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay: > http://barzilay.org/ Maze is Life! _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
