2 ms·

> perfectly secure and unlikely to ever have a kernel exploit ever again -_-

gjsman-1000 3y ago
It's actually not my words on this one. The Nintendo Switch uses a completely homegrown microkernel, that a single open-source developer (SciresM) was able to reimplement from scratch single-handedly. This would normally have a performance impact, which is partially mitigated by having the Switch permanently reserve 1 core for the OS and many other optimizations. However, the microkernel design is intrinsically much more secure than the monokernels used by Xbox (NT) and PlayStation (BSD). Outside that tiny kernel, everything runs in a sandbox, in userspace and not kernel space. Graphics drivers? USB drivers? The games themselves? All in userspace, confined to minimum functionality, and W^X. Exploits in the USB drivers, WebKit, and games are actually fairly easy to find on the Switch, but useless for launching homebrew from. The last exploit bad enough to launch homebrew in Nintendo's software was over 4 years ago. Some commentary from the developer (SciresM) who reimplemented it from scratch (everything below comes from https://www.reddit.com/r/emulation/comments/hygtnx/mesosphere_opensource_nintendo_switch_kernel_now/ https://www.reddit.com/r/emulation/comments/hygtnx/mesospher...): "It is a completely unique microkernel with a cooperative (non-preemptive) scheduler. The kernel is secure -- so far as I can tell (as a reverse engineer and hacker), it has zero security bugs. They throw out years of backwards compatibility (they're not POSIX/UNIX), and they really, really benefit from it from a security and modularity PoV." "Horizon's the only meaningful RTOS with a microkernel that I'm aware of (other than Fuschia). Everything's in userland -- filesystems, gpu (and other device drivers). The OS is capability-based and conceptually all about lots of different processes/drivers ("system modules") that host microservices. The fact that Nintendo designed such a rock-solid, modular, custom operating system for their consoles fascinates me."

It's actually not my words on this one. The Nintendo Switch uses a completely homegrown microkernel, that a single open-source developer (SciresM) was able to reimplement from scratch single-handedly. This would normally have a performance impact, which is partially mitigated by having the Switch permanently reserve 1 core for the OS and many other optimizations. However, the microkernel design is intrinsically much more secure than the monokernels used by Xbox (NT) and PlayStation (BSD). Outside that tiny kernel, everything runs in a sandbox, in userspace and not kernel space. Graphics drivers? USB drivers? The games themselves? All in userspace, confined to minimum functionality, and W^X. Exploits in the USB drivers, WebKit, and games are actually fairly easy to find on the Switch, but useless for launching homebrew from. The last exploit bad enough to launch homebrew in Nintendo's software was over 4 years ago. Some commentary from the developer (SciresM) who reimplemented it from scratch (everything below comes from https://www.reddit.com/r/emulation/comments/hygtnx/mesosphere_opensource_nintendo_switch_kernel_now/ https://www.reddit.com/r/emulation/comments/hygtnx/mesospher...): "It is a completely unique microkernel with a cooperative (non-preemptive) scheduler. The kernel is secure -- so far as I can tell (as a reverse engineer and hacker), it has zero security bugs. They throw out years of backwards compatibility (they're not POSIX/UNIX), and they really, really benefit from it from a security and modularity PoV." "Horizon's the only meaningful RTOS with a microkernel that I'm aware of (other than Fuschia). Everything's in userland -- filesystems, gpu (and other device drivers). The OS is capability-based and conceptually all about lots of different processes/drivers ("system modules") that host microservices. The fact that Nintendo designed such a rock-solid, modular, custom operating system for their consoles fascinates me."