I don't think so, the XNU and macOS LS architecture doesn't assume you're going to do policies based on the internal memory topology of a process. It's usually

I don't think so, the XNU and macOS LS architecture doesn't assume you're going to do policies based on the internal memory topology of a process. It's usually done with multiple processes and having one be very constrained doing only some very specific calls and the other not being able to do any calls at all. You can probably get by with mprotect or mach internals, but if you're developing at that level you've probably already either implemented or dismissed that. It's a bit of a different architecture with PAC/MIE/APRR (and to a degree AMFI) being used to prevent abuse that would require syscall filtering in the first place. While I personally don't think that's airtight, it does appear to work out well for their ecosystem. Edit: come to think of it, region-based call filtering is never really going to be enough on its own, if you don't combine it with other techniques it's basically a rop gadget fest. Probably also why SBX went for intent rather than trying to do it based on location/origin.