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New Two-Headed Hard Drive Intended To Secure Web Sites
dlur writes: "This article states that Scarabs (In Japanese), a Japanese company, is developing a hard drive with two heads, one read-only and another that is read/write. With this comes two cables, the read-only side going to the external web server, and the r/w cable going to an internal protected server. While this should make it quite a bit tougher for script kiddies to place their mark on a page, I doubt it will stop any real hackers from getting to a site's DB as that would still need to be r/w."
It seems a malicious user could still attempt to serve defaced pages off of a ram disk on the compromised machine. Yes, a reboot will fix the problem, but that's only slightly more convenient than restoring a compromised system from backups. Furthermore, I suspect that the read-only harddrive would encourage admins to become lazier with regard to applying server patches, since the system would be perceived as "secure".
As Timothy points out, this only prevents script kiddies from being able to modify existing content using a backdoor or whatnot. However, it won't do anything about denial of service attacks, since the server software and its modules/plugins are all in RAM, and will still be receiving inputs. Buffer overflows and whatnot are still possible. However, defacements will at least go away, and those are the second-most high-profile types of attacks, as they're visible to the general public. Database attacks would be the worst, though, since, as Timothy again points out, they must be writeable.
"Mod, mod, mod...and another troll bites the dust."
You don't need to write to the disk to make a compromised server serve up bogus content.
Furthermore, we can already do this same thing by mounting a network file system (say) in read-only mode. Other than being funky, what's the point?
Remember you can do the SAME thing with the hard drive you currently own and a CD drive. Here are some simple instructions...
/mnt/cdrom
A create your website
B burn it to CD
C modify httpd.conf, document root, set to
Voila! and I didn't need to hire a team of japanese researchers to figure it out either.
This would completely screw up any modern OS (or Windows).
The OS assumes that it, and it alone, modifies the disk, and that the disk won't change state without the OS making that change. This is one of the reasons you don't want to allow raw disk access from a VMWare or DOSemu session to a mounted file system - the emulated OS will access the disk, and the host OS's file system won't know about it. Boom! Instant corrupted file system.
In the case of this double-ended drive, the web server will assume that, since it has read the disk once, it needn't read that sector again. Then the write side computer modifies the disk, and the web server won't pick it up.
I'd rather see a disk with dual heads, and the logic to allow the system to read different sectors at the same time, all kept coherent by the drives controller as a way to increase throughput.
But to use this as a protection on a web server is just plain dumb.
www.eFax.com are spammers
Sure, this new drive can protect existing data from destruction, but we need protection from the wrong people reading the information that's already in a website.
Height: 38U, Weight: 0 Newtons, Eyes: #0000FF, OS: Gray Matter 1.0 (Alpha)
I thought of this as well, back when I interviewed at ReplayTV (I didn't get in, but that's neither here nor there).
Why not make a hard drive with two arms? They would be located 180 degrees apart from each other, so they would never bump into each other.
Each arm would be able to access the entire range of the hard drive.
One would be read-write and the other would be read-only, or both of them could be read-write if there would be no significant increase in cost.
This would be great for TiVo and ReplayTV units, which need to read large continuous amounts of data while writing large continuous amounts of different data! And it would be much quieter than the current one-arm drives, that have to thrash, making the units more appealing in a residential environment (one of the main complaints about the units is that the drives are too loud).
Considering the large quantities of drives that TiVo or ReplayTV use, is a special order out of the question? I'm sure this has been thought of before, and with a large enough order, anything is possible within reason. Western Digital made a custom drive for a large order, and found it to have such a good idea that it was officially added to their product line! (It's the larger 8MB cache in a "special edition" of their 100GB drive.)
Unfortunately this kind of drive would not work well with IDE. IDE is designed to wait for one command to complete before executing another command. So this means that the gain of being able to execute read-write commands in parallel would be neutered by this protocol. A solution is to use a SCSI drive that supports Tagged Command Queuing (TCQ)! This drive, if the controller and OS software support it, can stack up multiple commands that can be resolved in any order, as fast as the drive allows. This means that multiple outstanding commands could be sent to the drive, and the drive firmware would be free to execute them in the optimal order.
This would be a great advantage, as it could allow a slower drive to be used (less power consumption, less heat, less chance of failure). The slowness of the drive would be offset by the two arm design, making the drive effectively twice as fast. It might be even faster than that, as seek time would be reduced to almost nothing when reading or writing simultaneously from two different places!
The only disadvantage would be increased cost of having to use a SCSI drive (including controller) versus an IDE drive, and a one-time cost of having to add support for TCQ to whatever OS that is being used.
I wonder if a two-arm drive is being planned for use in ReplayTV or TiVo units? It seems like too good of an idea to pass up....
Dr. Demento On The 'Net!
Instead of saying that the sun can burn you, he told someone sitting in a dark closet that they are going to get burnt if they stay there. Still maybe not flamebait, but if you are going to type in l33t to look cool, at least read the article.
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