That depends doesn't it? You'll be safe from Little Snitch but Little Snitch will have less power to protect you.
Also, I wouldn't be surprised if people working on the Network Extension framework were exactly the kind of people who want to be able to continue use Little Snitch themselves.
i assume they and other devs in the space also are working with apple to get the necessary API calls for feature parity with prior versions.
apple will make them waste lots of time with one support team while another team implements iSnitch, part of next osx, using private apis.
It's all about the threat model. Engineers at the company were considered trusted actors and they were the only ones permitted to connect. If that layer failed, there is no way cache invalidation errors would be the fastest way in.
Security mechanisms which prevent you from doing the thing you're setting out to do are worthless. Making a computer too slow to be useful is one of the ways to do that. In this specific case, if moving Little Snitch's functionality to userland means that the performance hit of running it was large enough that I have to turn it off when doing network performance sensitive things (say, video conferences) then it'd be a net loss in security compared to the status quo of it running in kernel mode.
Also not like limiting vulnerabilities to user space is always a big improvement. If someone hacks my user account on a single user computer, they have access to all the data I care about anyway. They could ransomeware my stuff even without kernel access.
It's a long journey - started using Windows. macOS is a nice gap-stop, but the long term destination is probably something like OpenBSD or Qubes OS.
Perhaps eventually replacing much of the old software on my machine with stuff written in memory safe languages like Rust. There's some far-off efforts like Redox OS that may well end up being an option for me.
I keep my eye on security developments and I try to improve my situation as and when I have the time/energy to.
EDIT: To say, I have also switched from iOS to Android - after many years of waiting till Android itself became more secure. I've also dumped a lot of non-free software like Google Authenticator for free alternatives like andOTP. I'd like to eventually run something like Replicant or whatever is current/actively developed in the future.
But this is just me. Everyone should use what they are comfortable with.
https://arstechnica.com/information-technology/2020/03/found...
>Badly written device drivers can cause severe damage to a system (e.g., BSoD and data corruption) since all standard drivers have high privileges when accessing the kernel directly. The User-Mode Driver Framework insulates the kernel from the problems of direct driver access, instead providing a new class of driver with a dedicated application programming interface at the user level of interrupts and memory management.
If an error occurs, the new framework allows for an immediate driver restart without impacting the system.
https://en.m.wikipedia.org/wiki/User-Mode_Driver_Framework
Has Windows suffered from this change or has the added stability of having a graphics stack capable of restarting itself on error instead of blue screening the entire machine been a good thing?
I think they value the security and reliability from evicting those kernel extensions and nobody dreams of using this in some high performance production switch so I think it’s ok.
But yes, network perf is needed only for workflows that involve large remote resources, and not to all video editing use cases out there.
You'd maybe have a point if it were an L4, but mach ports are used as an example now of how not to do microkernel IPC because of how much overhead they use.
When your only goal is to avoid throughput bottlenecks, you don't need anything fancy. Avoid having a context switch per packet and you're most of the way there. A context switch every millisecond, or something in that order of magnitude, is completely harmless to throughput. If it causes your core to process 10% fewer packets than if it had zero context switches, then use 1.5 cores. Context switches take nothing anywhere near a millisecond each.
> Another factor that negatively affects performance is context switching. When an application in the user space needs to send or receive a packet, it executes a system call. The context is switched to kernel mode and then back to user mode. This consumes a significant amount of system resources.
And they're talking about the socket API, so when they say "a packet" they really mean "any number of packets".
The rest is mainly about metadata that needs to be maintained specifically because kernel and user are in different address spaces and can't directly share in memory data structures, and is additionally exasperated by splitting the device driver away from the network stack like macos is doing.
The only part that isn't ultimately about the user/kernel split and it's costs is the general protocol stuff in the network stack, and that was always the most specious of the claims of DPDK anyway.
Just so you know, you're talking to someone who used to write NAS drivers.
It's completely different if you have one switch per packet vs. one switch per thousand packets.
You're taking things to a ridiculous extreme to imply that any amount of context switching is a deal-breaker. There is a specific number of context switches before you reach 1%, 10%, 50% overhead. There are many reasons to avoid context switches besides overhead, but they are all either based on the underlying implementation or simply not critical to throughput. You're oversimplifying, despite your credentials. The implementation can be changed/fixed without completely purging context switches. There are many tradeoffs, and doing pure user-space is a viable way to approach things, but it's not the only approach.
Memory sharing and metadata slowness is an easy bottleneck to have, but the way you avoid it, by changing data structures and how you talk to different layers of code and the device, can be done whether you put it in the kernel, in pure user space, or split it between the two.
Wouldn’t these be Meltdown mitigations?
The network stack in Windows is a part of the kernel and I haven't heard of userspace implementations of it like DPDK or PF_RING in Linux. GP is wrong about the performance of them though, as you can actually enhance it in a userspace mode (good article from Cloudflare [0]).
[0] https://blog.cloudflare.com/why-we-use-the-linux-kernels-tcp...
Anything tun-based tends to have the same problem.
Anyone that remembers WinNT 3.51 or so would likely remember the horrible video performance before most windows graphics code was moved to the kernel in win32k.sys...
Apple will just slowly write itself into the equation so that little snitch can no longer mess with whatever muddled idea apple seems to think is important.
Already with Catalina you have to connect to apple and ask permission before you can even install little snitch. That means little snitch can't protect you from apple, even if you've told apple "my machine doesn't connect to the internet".
And your machine contacts apple every bit as often as microsoft machines even though their philosophy is supposed to be different.
bottom line: you should not have to ask apple permission to do anything with your machine.
From those commercial vendors, I have worked with Xenix, DG/UX, Solaris, Aix, HP-UX, Tru64.
None of them ever cared about being philosophers.