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Qubes OS: A reasonably secure operating system

(www.qubes-os.org)
441 points ploggingdev | 1 comments | 19 Nov 17 16:06 UTC | HN request time: 0.205s | source
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snvzz ◴[19 Nov 17 17:00 UTC] No.15734641[source]▶
Their weakest point is the hypervisor, Xen, which while a better choice than Linux/KVM, is still extremely bloated and has a poor security history.

Thankfully, better designs such as seL4's VMM do exist, although it might need a little more work [1] until usable for the purpose.

[1] https://sel4.systems/Info/Roadmap/

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mmrezaie ◴[19 Nov 17 17:17 UTC] No.15734739[source]▶
Xen's hypervisor's size is very small. Qubes is about security and trustability of the whole system. In operating systems for measuring the trustability of the system, one very important measure is the lines of the code. Xen has a smaller footprint in the hypervisor part. Additionally, Xen has a robust model isolation for the drivers. That's why they went for Xen not KVM. But boy I wish to see more seL4. It was sad to see Gnu Hurd/seL4 didn't make it.
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snvzz ◴[19 Nov 17 17:25 UTC] No.15734790[source]▶
>Xen's hypervisor's size is very small.

150kLoC is quite a bit for an hypervisor.

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1. mmrezaie ◴[19 Nov 17 19:25 UTC] No.15735435[source]▶
way smaller compared to KVM/Linux's but compared to seL4's 10k LOC it is huge which is why seL4 is a good candidate as industry standard size for trustable hypervisor layer [1] but I am not sure how and what happened to L4Linux project other than being just an academic project!

https://www.sigops.org/sosp/sosp09/papers/klein-sosp09.pdf