On 15/11/2023 17:13, Rob Spoor wrote:
Hello all,
I'm working on a module that makes working with FFM easier; think of
something like JNA. For instance, it allows creating structures
without having to manually manage var handles etc.
My module uses restricted mehods like AddressLayout.withTargetLayout
to support pointers. Those correctly give warnings if I don't use
--enable-native-access. This is where I've identified a potential
security risk. Native access would need to be enabled for *my* module,
which would allow modules that use my module to call these restricted
methods indirectly and without needing native access enabled
themselves. This means that any malicious module could piggy-back on
the native access that would be enabled for my module.
I can implement my own access checks using the following:
StackWalker.getInstance(Set.of(Option.RETAIN_CLASS_REFERENCE))
.getCallerClass()
.getModule()
.isNativeAccessEnabled()
However, that would mean users of my module would need to provide
access using two different mechanisms.
These kind of stack walker checks based on problematic as it be
something further up that stack that you have to authenticate rather
than the direct caller. So I agree with Maurizio, this looks like a case
where you using a Lookup object would be better.
-Alan
