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On Mon, Jan 18, 2016 at 12:06 PM, Grant <emailgrant@×××××.com> wrote: |
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> |
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> I am 100% web-based. I don't want to administrate machines outside of |
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> my LAN so I can imagine a Chromebook would end up vulnerable |
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> eventually. |
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The whole point of chromebooks is that they auto-update in a timely |
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fashion, and have a guaranteed end-of-life policy years into the |
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future. Sure, not quite as far as Microsoft guarantees, but nobody |
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runs a Windows laptop for even the length of a typical Chromebook EOL. |
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The chromebook also has secure boot and a signed OS, so if it is |
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corrupted it will go into recovery mode. You just stick a USB drive |
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with a rescue image on it (which you can create from any PC with a |
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chrome browser or an installer) and it fixes itself. I don't think |
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you can even turn off auto-updates - they're designed to be |
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idiot-proof. I'm not sure if as an enterprise administrator you can |
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set up a policy to force a reboot to update within n days or such if |
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it hasn't been shut down already after an update. |
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In any case, if you aren't going to own the client hardware, you |
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basically are going to have to assume it is vulnerable since nobody |
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maintains their PCs well. That means keyboard sniffing, cookie |
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stealing, and so on. If you're web-based a hostile browser could just |
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open another session in the background after the user authenticates |
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(2-factor or otherwise) and do whatever it wants to. Granted, I don't |
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know if anything is out in the wild which actually does this, and it |
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would probably need to be somewhat targeted to work (unless somebody |
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has a rootkit that just lets them interactively fire up another |
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browser on a VNC display or something using the same browser session). |
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Sure, a Chromebook will cost you $150, but that seems like a token |
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expense for an employee and it buys you a LOT of security. You can do |
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the same thing on another OS, but you're going to end up adding on a |
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lot of stuff on top of the OS to make it work, and I'm certain the |
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administrative overhead would be much higher. A chromebook is |
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basically what you get if you take a linux desktop and lock everything |
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down with TPM support and secure boot - they're even based on Gentoo. |
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Sure, you can DIY, but you're not going to do better without the |
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hardware support. |
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> Someone mentioned 2-factor authentication which sounds interesting. |
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> Are there good options for that besides SMS and Google Authenticator |
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> (or a similar mobile app)? Is there a good 2FA server in Portage? Is |
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> 2FA ever defeated in real life without the user's phone? |
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Do you mean you don't want something that involves typing in a TOTP or |
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similar? Google Authenticator just uses RFC 6238 so you can use any |
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other compliant client to generate the codes - I'm sure those exist |
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for Linux, but if you're going to do that you might as well just use |
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an RSA-based authentication since if you can steal the client key you |
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can steal the RFC6238 key. The whole point of 2-factor is that the |
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second factor tends to be something that isn't on the same PC as the |
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client. |
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There is a PAM-based authenticator in portage for Google |
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Authenticator, which again should work with anything RFC 6238 |
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compliant. I use it for ssh password logins and it works great (well, |
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aside from having to reach for my phone anytime I log in via an |
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untrusted computer). |
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A much older option is s/key. I'm sure that is still around as well, |
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but I don't think it really has any advantages over RFC6238. |
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-- |
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Rich |
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