Building a Fully Encrypted NAS On OpenBSD

mistermark writes "Two years ago this community discussed my encrypted file server. That machine has kept running and running up until a failing drive and a power outage this last week. So, it's time to revise everything and add RAID to it as well. Now you can have an on-the-fly encrypting/decrypting NAS with the data security of RAID, all in one. Here is the how-to."

Netcraft...

mistermark's failed hard drive only further confirms that BSD is, in fact, dying.

Pretty In-depth

Wow, that was a pretty in-depth how-to. It even has a mechanism (via cron) to notify you within 15 minutes if a drive fails. This sounds like a pretty interesting solution. I think I may have to give it a try with a spare box I have laying around. Than

Re:

I'm shocked the raid tools for OpenBSD aren't better then that. Not a dig at it, OpenBSD generally prides itself on exceptional tools. OpenSSH, CARP (their replacement for VRRPD), their firewall tools and everything else. Linux has a system call that ca

Re:

interestingly I have had localized brown outs in parts of my house....

I have underground power and water got into the line.. and one of the legs would drop in voltage for no reason.. so instead of 2 120v legs coming in I had 1 120 and 1 60v leg.. when say

One link in the chain...

One step in the long process. Kudo's and gratitude for putting this up, it will certainly make my process easier.

I wonder, are there any full HOWTO's on this? 802.1x and IPSec both come to mind. The protection is useless if the server is powered on of course.

Re:One link in the chain...

Thanks for clarifying the OP's error, but why the patronizing tone?
Most people on the planet don't speak English natively, and a large part of the Slashdot population is from that group.

Since you can't tell if the OP does or does not belong in that group, being a little less harsh would make the world a nicer place. Why not start there?

Been looking for something like this

Although, since the OS is just there to boot and allow access to data, I was thinking of using a 1GB CF card to put the OS on. I like the RAID 1 setup the instructions are easy to follow, but how about other RAIDs?

Re:

Just make sure you don't follow TFA's recommendation regarding the choice of identical drives for the RAID array, which would make the whole point of redundancy moot.

Identical drives are just that, identical. This means that they also are very likely to fa

Re:

Actually, Identical drives are in fact, not identical. What they are is built to the same specifications. They actually use different atoms and molecules to make up the components of the drive. They were most likely manufactured on different days, or at

needs usability

Right from the initial install, by default, this should work.

Encrypted backups should be default and easy, with reminders.

You need multiple keys: whole-system, per-user, and swap. The swap key gets replaced at boot with something random.

Ultimately, it needs mandatory encryption. This would exclude OpenBSD; you need a mandatory policy framework like SE Linux to make it happen. Mandatory encryption means that normal users are prohibited from removing data from the machine without first encrypting it in an approved way. This most likely solves part of the backup problem. It also reduces the insider threat, while still allowing transfer of data between secure machines.

Re:

Mandatory encryption won't help a whole lot. Mandatory access controls that utilize encryption might help some - it doesn't protect off-site data but DOES limit the device you copy data onto, as the device must be authorized to hold the data. It is then th

ZFS

Any idea if OpenBSD supports Sun's ZFS filesystem?

-metric

freenas...

Meh...

1. download FreeNAS [freenas.org]
2. install to USB/CF drive (it needs ~32Mb)
3. configure * reboot on the USB/CF drive (or if your mobo cant boot to those, maybe a CD or spare HD)
4. ?
5. Profit!

Tm

Pretty Useless

Seeing as that he uses per-volume encryption, this is pretty useless. It makes his 'server' pretty much a single-user NAS box, because as soon as another user gets an account to access the file server, they get access to the data.

Data encryption on a fileserver only makes sense if it is done on a per-user level. This is not News for Nerds, as this is basically just another implementation of how to encrypt your local disk.

Mart

Re:Pretty Useless

Seeing as that he uses per-volume encryption, this is pretty useless. It makes his 'server' pretty much a single-user NAS box, because as soon as another user gets an account to access the file server, they get access to the data.

As long as the server remains physically secure, and assuming there aren't gaping root privilege holes in the security, the files on the disk are still protected by the file system permissions. As long as the users can trust the admin, they don't have to trust each other.

Data encryption on a fileserver only makes sense if it is done on a per-user level. This is not News for Nerds, as this is basically just another implementation of how to encrypt your local disk.

Databases with private information like credit card or social security numbers should be on encrypted disks. Not to protect against users, but to protect against the drive being replaced or stolen before it can be wiped (secure wiping is not necessarily secure either, especially as drive technology advances, since what was wiped 5 years ago may be easily readable now).

There's really no advantage to having a server encrypt and decrypt each user's data with a different key. The server will have to know all the keys to perform the decryption at least (public keys allow secure encryption without the server knowing the private key), so it's only as secure as encrypting the entire drive and then relying on filesystem permissions. Root will always be able to read any files that are encrypted/decrypted on the server itself. If clients encrypt their files before storing them on the server, then the server can safely store everything in plaintext.

Re:

There is really no advantage to encrypting data if you have other means to restrict access to a server.

Volume encryption only makes sense if there is a significant risk of losing physical control over the volume, i.e. on portable media. If your hypothetic

Suggestions

OpenBSD on a fileserver? Firewall, sure. Fileserver w/RAID and disk encryption, no way. I would leave that task to FreeBSD (FreeNAS) or Linux (CryptoBox, Openfiler). If you are desperate for encrypted FS + RAID you can use MD + LUKS (Linux) or GRAID5 + GELI (FreeBSD) those are all available via FreeNAS, CryptoBox, and Openfiles. Suffice to say both have proven their stability, have a rich set of features [wikipedia.org] (e.g. LRW), and are simple to set-up. The end-user NAS solutions are pretty sophisticated and have good web interfaces.

20 MB/sec is quite a shit performance IMO however if you don't use gigabit it'd be good enough. With GELI there is about 55% overhead compared to plain text. I haven't compared LUKS to plain text hence can't compare. On a side note, I doubt its useful to encrypt data you're receiving from distributed areas, nor that its useful to put such data in a RAID. A NAS doesn't run BitTorrent. If you're paranoid whereas you share your data over SMB, that might be the weakest point.

For our ricer folk, a nice, expensive RAID controller is necessary. For the smart people among this planet: do software XOR by getting an EE (or SFF) dual core AMD which are cheap and have a a low 10 idle W and have a low TDP (the SFF has 35W TDP). Get 4 Samsung SpinPoint T166 SATA (silent, low power, best bang for buck) and you have 1,5 TB RAID. All in all this costs about 650 EUR (probably less in USA) w/all hardware new including case, 2 * 1 GB RAM (2 * 0,5 GB would suffice too), and PSU. I should know, I bought and build such machine.

Forget ZFS for now. OpenSolaris has bad hardware support, and it is only partly ported on FreeBSD 7.0-CURRENT where it isn't stable and a bug in it takes the whole system down. While it does have a rich set of features, it also doesn't support encryption yet, although the feature has been planned for a year and perhaps on FreeBSD it can be used together with GELI. Performance of ZFS is also not to write home about compared to GRAID5. ZFS isn't mature yet. Nor is FreeBSD 7.0-CURRENT, ofcourse. It'll be part of FreeBSD 7.0 however, as an experimental feature.

An explanation

Kdawson clearly killed the other editors, and is now posting all stories. If you see anyone else posting, it's actually kdawson using their account. Look for more dupes, April Fool's Day jokes, and Slashvertisements soon.

Re:USB drives?!?

USB was o.k. last year, but with 20GB/sec effective transfer rate at most, it simply doesn't do a large modern HDD justice anymore.

    Jeeeeezus! Either I'm way behind the times, or your "GB" was meant to be perhaps a thousand times smaller.

Re:USB drives?!?

When is your next book "More Typo's I found on the Internet" coming out?
It's late and nitpick stuff like this has been driving me nuts all week.

There shouldn't be an apostrophe in Typos...

Re:

Yeah sorry, It's late and nitpick stuff like this has been driving me nuts all week.

"Why do you have a captain's wheel around your waist?"

Re:

It does not. If we read through the article we do find, however, that the author suggests FreeNAS for a NAS, OR CryptoBox [cryptobox.org] for hardware encryption. IMHO neither solution leads to the extension into a full blown server that the OpenBSD option gives.

My $0.02

Don't use loop-aes anymore.

Use dm-crypt with LUKS in the aes-cbc-essiv:sha256 mode (should be the default). There are policy issues and known plaintext attacks against loop-AES unless you the multi-key setup which _isn't_ the default... by the times the issues were widely known peop

Re:OK

WTF
IsA
NAS
?

http://en.wikipedia.org/wiki/Nas [wikipedia.org]

Re:

The only advantage to buying a RAID controller is that you get a lot of connectors. Otherwise, if you have any even fairly decent CPU, and you're not doing anything but shoveling data and maybe some logging, the main processor beats the living shit out of almost any CPU on any RAID controller. There are limited exceptions but those cards are highly spendy.

And keeping a lot of data off of the interface bus. Hardware RAID controllers are all about delegation. Get the data off the bus and onto the card as fast as possible, without sending it over the bus multiple times. Which is less of a concern in the days of boards with 30+ PCIe lanes. [...] Instead of being able to tell the controller "write these X bytes of data" and only sending X bytes across the PCI bus, with Software RAID, you're probably looking at at least 2x (RAID1) up to 4x (RAID5) the bandwidth usage to write data.

It's true that the more computation is involved, the more serious the bus bandwidth issue gets. This is an excellent reason to build software-based RAID systems with Hammer-core processors today; they have their own memory controllers onboard. Thus the R