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A Closed Off System?

AnarkiNet wonders: "In an age of malware which installs itself via browsers, rootkits installing themselves from audio cds, and loads of other shady things happening on your computer, would a 'Closed OS' be successful? The idea is an operating system (open or closed source), which allows no third party software to be installed, ever. Yes, not even your own coded programs would run unless they existed in the OS-maker-managed database of programs that could be installed. Some people might be aghast at this idea but I feel that it could be highly useful for example in the corporate setting where there would be no need for a secretary to have anything on his/her computer other than the programs available from the OS-maker. For now, let's not worry if people can 'get around' the system. If each program that made up the collection of allowed programs was 'up to scratch' and had 'everything you need', would you really have an issue with being unable to install a different program that did the same thing?"

44 of 177 comments (clear)

  1. Wouldn't a live CD do this? by amanda-backup · · Score: 5, Insightful

    Doesn't a live OS CD such as Knoppix achieve this goal? These are usually built for "everything you need" for a particular purpose. You can still access and create data on disks on that system, but you never corrupt the programs themselves. If all the applications being used are web based, then things are even simpler - simply boot up with Knoppix, open Firefox and you are ready to go.

    1. Re:Wouldn't a live CD do this? by hey! · · Score: 2, Insightful

      I don't know if they're still sold this way, but firewalls used to be computers that booted off a live CD. This in a way is even more secure than the flash memory used in consumer devices, because presumbaly there's a way to remotely flash these units.

      As other people point out, this is not perfectly secure, because this doesn't prevent the device from loading software remotely and runnint it. However, it does reducee the scope for damage considerably: while you can't prevent data from being lost or corrupted, the real time consumer in recovering from a subverted system is bringing the system back up to a state where you can trust it. You can reboot the system back to its original state, then plug in your updated virus/spyware scanner and run it.

      From a computer science perspective, you can't really "close" a system completely, any more than you can have an organism that runs without RNA: the fact that instructions and data are the same thing are at a deep level part of our very concept of what a computer is. Take a file in a fairly complex format, say Microsoft ".doc". What is that file but a program executed by the Word doc interpreter to create a visual representation of a document? What is Word but a specialzed compiler/interpreter for such programs? Thus, most of the non-trivial programs on an operating system are, in a sense, virtual machines. If any of these virtual machines have any kind of flaw, then a malicious programmer can get them to do things the user does not want.

      If you're making a virtual machine, you want to limit what programs running on that machine do on the underlying computer. Sun realized that when they sandboxed Java applets. The problem is that this is too restrictive to be popular with users. So you end up letting the user grant programs access to different resources. At that point, any vision of iron-clad security is gone, a victim of social engineering.

      --
      Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  2. What a load of... by Bin_jammin · · Score: 4, Funny

    fun you must be to think up questions like that.

  3. Windows Group Policy by Ececheira · · Score: 5, Interesting

    Windows has long been able to do this via Group Policy. You can specify that only programs signed with specified Authenticode keys can be run, effectively locking the system. Since all OS files are signed by Microsoft and anything a corporation would need could be signed, then if a corporation wanted a locked-down box, then they'd just specify the allowed keys and block everything else.

    It'd be a huge nuisance but it's possible today.

  4. I'd use it by Wizarth · · Score: 3, Interesting

    For office use, a linux distro (such as Debian or Ubuntu) which allowed you to specify the repositories, and not allow modification of the list, would work just fine, in general.

    System admin's would only allow updates from the offical repository, with a local repository for mirror/caching and business specific software packages.

    I use something like this for my relatives. Give them a linux, don't give them root, make all updates/installations go through me.

    Then print out a poster for my door "setup.exe will not run on your system" ...

    1. Re:I'd use it by morcego · · Score: 2, Interesting

      "noexec" is completely useless.
      Just do: /lib/ld-linux.so.2 YOUR_PROGRAM
      and you can bypass noexec.
      Not to mention shell scripts, perl etc etc.

      --
      morcego
    2. Re:I'd use it by 19thNervousBreakdown · · Score: 2, Informative

      From man mount (eww):

      noexec Do not allow direct execution of any binaries on the mounted file system. (Until recently it was possible to run binaries anyway using a command like /lib/ld*.so /mnt/binary. This trick fails since Linux 2.4.25 / 2.6.0.)

      --
      <xml><I><am><so><damn>Web 2.0</damn></so></am></I></xml>
  5. On the subject of the CD Rootkit... by GhaleonStrife · · Score: 3, Interesting

    Think about this: If that database included the infamous Sony rootkit as "allowed" due to them laying pressure on whoever maintains it, doesn't it render the whole thing pointless?

    1. Re:On the subject of the CD Rootkit... by bersl2 · · Score: 2, Insightful

      The whole shitstorm over "Trusted Computing" and this are essentially the same topic, and the issue is who has control over the access control list, the user-administrator or some other party. The feature can be used for good or evil, for lawfulness or chaos, just as with any other tool.

    2. Re:On the subject of the CD Rootkit... by Kjella · · Score: 2, Insightful

      Think about this: If that database included the infamous Sony rootkit as "allowed" due to them laying pressure on whoever maintains it, doesn't it render the whole thing pointless?

      So your argument is basicly that because trust can be misplaced, there's no point in having a trust system? Let's remove the classification system because the joint chiefs could be Al-Quaida members. Let's remove all digital signatures because the signing key might have been compromised. The point is who to trust, and also look out for misuse of the word trust. For example, TCPA software is less trustable from a computer security point of view because it can't be audited. For example, I trust the debian signed packages, in the sense that they're official packages of the software and not trojaned versions. Of course, the maintainers of the package may install a trojan but that's a lot less likely. Trust rarely works in absolutes, degrees of trust is the norm. Being on that database would be one of these levels, though honestly I don't see the big problem in corporate environments. Don't give users admin rights, install only serious software downloaded or bought from official sites. I think the actual number of rootkit cases where those procedures are followed are almost zero.

      --
      Live today, because you never know what tomorrow brings
  6. code isolation by TheSHAD0W · · Score: 4, Insightful

    This would be "mostly secure", but unless strict data-space separation would use it might still be vulnerable to a buffer overflow or similar attack that would allow arbitrary code provided as data to be executed. The attacker would use this opportunity to establish a "beachhead", modifying whatever integrity-checking system the OS is using to allow it to continue to exist.

  7. Question moot. by The+MAZZTer · · Score: 3, Insightful

    "If each program that made up the collection of allowed programs was 'up to scratch' and had 'everything you need',"

    Considering that is impossible, the question is pretty much moot, isn't it. I am always going to find more needs for things, and chances are I'm going to need a new piece of software. Even if an OS shipped with "everything", new things are invented all the time. Maintaining a "Closed OS" to allow for new things would be difficult, and to keep it relatively up to date even more so... but then it wouldn't really be closed if new stuff kept getting added to it...

  8. Treacherous Computing by jZnat · · Score: 3, Interesting

    This is exactly what Microsoft would like to do with Treacherous Computing, although the issue would cover things like security from the user rather than for the user.

    --
    'Yes, firefox is indeed greater than women. Can women block pops up for you? No. Can Firefox show you naked women? Yes.'
    1. Re:Treacherous Computing by MaverickUW · · Score: 2, Insightful

      I hate to say this, but while the idea of security from the user instead of for the user, sounds insane, it's probably very needed and very valid.

      I've done some freelance computer work for people who don't know all the technical stuff about computers. This normally relates to spyware/malware/virii/etc. The grand majority of the spyware and malware is self installed. Downloading cutesy screensavers or cursors or backgrounds that come with all manners of desktop search, search bars. When you have a Athlon 64 3800+ with 2 GB of Ram and 10,000 RPM SATA drives in a raid array slowed to a crawl because of too much crap (with antivirus and antispyware software installed, something is wrong.

      I've even seen half the spyware removing programs that show up as spyware themselves in AdAware!

      We're getting to a point where security FROM the user is almost if not more important than security FOR the user.

  9. Smith-Corona to the rescue! by Onan · · Score: 4, Funny


    Yeah, turns out somebody was doing this for kind of a while. Called them "typewriters" or somesuch.

    Really, much of the value of a computer lies in the fact that it's an extremely versatile device. Choosing to discard all that, and believe that you can know ahead of time every single thing you will ever want to accomplish with it, seems like a pretty bad deal.

    1. Re:Smith-Corona to the rescue! by bcat24 · · Score: 2, Insightful

      But there are some people who use a computer for nothing more than word processing, web browsing, and email. A "closed off" setup might work for them.

    2. Re:Smith-Corona to the rescue! by TheGratefulNet · · Score: 2, Informative
      But there are some people who use a computer for nothing more than word processing, web browsing, and email


      anyone remember the I-opener ? that was a closed (qnx) turnkey just-does-this-and-no-more system.

      I don't think the company lasted long, though. too many people (myself included) bought the boxes for $100 and hacked them to get linux and win95 on them. ahh..

      but the idea was kind of ok, for some people. and there was NO way to get viruses or problems when you aren't even running a real multiuser o/s like that.

      oh, and it had a pizza key. a pizza key. wow.

      (I still have that i-opener. I can't even imagine what a pent-120 class machine could be useful for, today, though. it wasn't even a real cpu, it was some cyrix animal, pretty feeble even for its day).

      --

      --
      "It is now safe to switch off your computer."
  10. OS X by mattjb0010 · · Score: 3, Interesting

    already does this. See here, under "Application Access: You Decide". You can set up another user account for yourself (not just any children) which would be protected. I'm pretty sure Windows has similar things (not sure if you need 3rd party software to do this) and as mentioned, there are live CDs of Linux/BSD/etc.

  11. Same thinking? by JayTech · · Score: 2, Insightful

    Isn't this the same exact thinking behind the TCPA planned by Microsoft & Co? Where only "licensed" software would be allowed to run? Doesn't sound like a bright idea to me, in fact it sound pretty scary.

  12. No. - Re:Wouldn't a live CD do this? by jdogalt · · Score: 5, Insightful

    No. LiveCDs do offer read-only system images. But they do nothing whatsoever to prevent other programs from being run. I.e. programs downloaded from the net, autorun(or manually) from cd. LiveCDs get you the benefit that each reboot resets you to an known state. That is quite different from an OS which only allows programs from a blessed whitelist to execute. One scenario might be the discovery of way to remotely log into the system. In the livecd case, the attacker can now run whatever program they want, and likely regain entry in an identical fashion should the system be rebooted. What the author of this post is interested in, is a system what would not let the attacker with remote login be able to execute any code not on the blessed whitelist. Now mind you, the idea that such a system would be 'invulnerable' is ludicrous. The XBox seems the quintessential example of a system which tried to achieve this design goal. My XBox currently runs ssh, freevo, and any executable I want, proving it is difficult to achieve a successful implementation of such a design. -jdog

    1. Re:No. - Re:Wouldn't a live CD do this? by secolactico · · Score: 2, Insightful

      The XBox seems the quintessential example of a system which tried to achieve this design goal. My XBox currently runs ssh, freevo, and any executable I want, proving it is difficult to achieve a successful implementation of such a design

      Yes, but you had to go out of your way in order to achieve this, right? That is, it's not something that happened because of soemething you downloaded off the net did away with the "protection" MS had installed originally in the machine. (Besides, as far as I know, only the bootloader needs to be on the blessed list).

      Of course, everything is fallible. And besides, if every single executable code had to be signed and verified, how expensive in terms of CPU time would that be?

      --
      No sig
    2. Re:No. - Re:Wouldn't a live CD do this? by jdogalt · · Score: 2, Insightful

      "Out of my way" is as vague a phrase as "should". Yes I had to follow some instructions, but technically I'm also following instructions when I dial my phone.

      Yes the bootloader only needs to be on the blessed list, but in the absence of a blessed bootloader which allows arbitrary code to execute...

      To your last point, signing and verifying every executable is not a heavy CPU tax. The real issue is the granularity, and if you can prevent any excutable which intentionally or unintentionally allows arbitrary external code to be executed from getting blessed.

    3. Re:No. - Re:Wouldn't a live CD do this? by Anonymous Coward · · Score: 3, Insightful

      What is an executable?

      No, the question is not a joke: What would such an OS do with Active-X and Java? Ok, they support digital signatures and let's believe such a system would work.

      And JavaScript? It's clearly executable, but would it be blocked? Who would use such a computer when 50% of websites are not viewable without JS? Not to mention sites that only exists in the form of one SWF file...

      On a server, JS would not be needed, but usually one needs customization in terms of scripts a.s.o. If the admin could self-sign programs (and would be so careful to only that with programs he wrote himself and where he is sure that no malware is included) on a second machine, that could work.

  13. Vista + 'DRM' Hardware by nuxx · · Score: 3, Interesting

    Huh. Imagine that... Something which can be done by having a Microsoft OS set to run only signed binaries while running on top of a 'trusted computing platform'.

    As I've said before, this would be a huge boon to IT departments all over the place. I'd love to be able to lock users to running a signed OS only the apps we specifically approve and sign. This would lock out all unapproved software *and* malware. If the OS is secure enough to keep there from being any ways around this, it'll be ideal.

    Oh, and of course, as long as such trusted computing stuffs can be turned off for users who purchase the hardware and don't wish to use it, it's a win-win all around.

  14. console? by minus_273 · · Score: 4, Insightful

    Anyone else think this sounds a lot like the xbox 360? encryption keys and all.

    --
    The war with islam is a war on the beast
    The war on terror is a war for peace
  15. Have had it for almost 30 years! by JoeCommodore · · Score: 4, Insightful

    Lets see the Commodore PET, Apple II and TRS-80 were pretty \much can't touch this OS without a hammer type computers.

    --
    "Enjoy what you're doing! If it becomes drudgery, you're doing it wrong!" - Jim Butterfield
    1. Re:Have had it for almost 30 years! by pyrrhonist · · Score: 2, Informative
      Lets see the Commodore PET, Apple II and TRS-80 were pretty \much can't touch this OS without a hammer type computers.

      Oh yeah? After booting Apple DOS 3.3 type the following at the AppleSoft BASIC prompt:

      POKE 47616, 96
      Now you can't read or write to a disk. Now that's malware!

      Free karma if you can name what routine I disabled.

      --
      Show me on the doll where his noodly appendage touched you.
  16. An OS without any 3rd party apps... by FreeMath · · Score: 4, Funny

    You mean like a Mac?

    --
    This sig intentionally left blank.
  17. Why not instead..... by ezratrumpet · · Score: 2, Interesting

    ....limit a machine to only outgoing traffic? That would let you use an office suite and send (but not receive) email.
     
    Downside: you'd have to use a CD or flash drive to transfer documents on/off the machine. You couldn't receive email on the machine.
     
    Upside: The only security risk would be by direct access.
     
    Actually, the most secure machines probably aren't even password-protected. If the machine isn't attached to anything but a power cord, and the machine itself is inaccessible, then you've got a secure machine. If you're running Win3.1 or something, it might DIE, but it would be a secure death.

  18. as a software developer... by Xtifr · · Score: 2, Insightful

    ...I would have to say no. At least not by itself. It's pretty hard to develop software if you can't install and test the software you're developing somewhere! ;)

    As a component of a larger, networked system, which had parts where I could install and run the software I was developing, then yes, no problem. But alone, by itself, no, it would be completely useless.

    Of course, there's still some interesting questions about this theoretical beast. Is it scriptable? I often have quick one-off tasks that are best done with a quick script. If I can't run one-off scripts, then it's not "up-to-scratch" and doesn't have "everything I need", and if it can, then it's not a completely closed, locked-down system. The only way around that, even in theory, is to have an infinite number of monkeys providing you with all the scripts you could ever need in advance, and even then, there's probably be some difficulty finding the script you need right now from that infinite number of scripts. (Not to mention the costs of the infinibyte drives needed to store all those scripts.)

    Bottom line, I think the notion of a machine that does "everything I need" is about as realistic as those old concepts of an irresistable force or an immovable object. Nice for creating logical paradoxes, but completely silly otherwise.

  19. *groan* by voice_of_all_reason · · Score: 4, Insightful

    ...it could be highly useful for example in the corporate setting...


    Oh, for fuck's sake! Don't give them any more ideas.

    The extra cost of technology staff and the risk of a shittastrophe are nothing compared to abysmal employee morale. If you don't let 'em stroke off for a few minutes a couple of times an hour by going to ebay or playing snood you're going to end up with a resentful staff. And they'll produce awful, crappy work for you.

    1. Re:*groan* by dosius · · Score: 2, Insightful

      Employer: That's not what I fucking hired them for, they're here to work for me.

      Me: I would leave the internal network detached from the Internet and remove all external sources of input except the keyboard/mouse, and put the OS on something read-only. Nothing gets in, nothing gets out. Works for work, not for play.

      -uso.

      --
      What you hear in the ear, preach from the rooftop Matthew 10.27b
    2. Re:*groan* by DrSkwid · · Score: 2, Insightful

      Access to the internet is NOT an entitlement at work.

      At least not wher I live. Do you have internet terminals for employess at the gas station ?

      Are the guys at the foundry revolting because they can't browse eBay while waiting for the steel to cool ?

      Soft in the belly workers need to wise up.

      --
      There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
  20. Hypothetical question: "lusers" as decoys by Kadin2048 · · Score: 4, Insightful

    Speaking as a user who understands their computer reasonably well and doesn't click on stuff just because animated characters tell me to, would this be a good thing?

    If we (hypothetically) closed off the "stupid user" vulnerabilities that are the major attack vectors right now, wouldn't the malware authors instead just concentrate on other, more technical, avenues of attack?

    Here's my thought: maybe having systems vulnerable to idiot users is actually a good thing for the informational ecosystem as a whole. They're more than just the canaries in the coal mine (although they serve that function, too), they provide a steady stream of marks for the virus/trojan/malware writers and phishing-scheme authors of the world.

    If these people weren't able to basically throw themselves on the swords of their own stupidity on a regular basis, couldn't this just lead to smarter malware, which affected more of us (not just the stupid/ignorant)?

    Malware authors are inherently lazy and opportunistic. While there are still lots of "the monkey told me to click it so I did" people around, and ways to exploit this idiocy, that's what they're going to do. They're not going to mess around with esoteric buffer overflows to steal your information, when they can just send out some fake PayPal emails and watch the data roll in.

    Given the choice, I'd rather have the primary attack vectors be ones that rely on user stupidity, rather than technical flaws, because 0-day technical flaws are too 'egalitarian,' attacking both the clueless user and the experienced person without warning. Personally, anything that keeps the collective attention of the Russian Mafia focused on people too dumb to check the URL line in IE before typing in their bank account information is a good thing in my book.

    I know this isn't a very nice sentiment to hold, but if there was some hypothetical way to remove user stupidity as a vulnerability (not possible, so this is all just a mind game), maybe we'd be better off not implementing it?

    I'm not suggesting that we shouldn't attempt to educate people on good computing practices, but if people are too lazy or disinterested to become educated, maybe in their laziness they can do the rest of us a favor by acting as the collective decoys?

    --
    "Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
  21. Re:not quite! by Goaway · · Score: 2, Interesting

    I agree, it can be locked down, as can most other modern OSes

    Oh, so how exactly do you lock down Linux so that only signed software can be run?

  22. Not on my PC by egarland · · Score: 2, Insightful

    I have no problems with this setup if the computer is my Cell Phone. My PDA could be setup to only run signed apps, that wouldn't bother me much. But my PC isn't really a PC without the ability to accomplish arbitrary tasks.

    The concept is also flawed. Just because something isn't an executable doesn't make it not contain instructions that tell your computer to do something. Word macro viruses is a great example of this kind of problem. It's just a simple word processing document.. but it can also be a virus. The .mp3 and .jpg buffer overrun bugs are great examples of this too. A format that doesn't even include programability can be used to induce your computer to do something against your will.

    This is not the answer to computer security.

    --
    set softtabstop=4 shiftwidth=4 expandtab nocp worlddomination
  23. Symbian OS 9.1 for cell phones. by S3D · · Score: 2, Informative

    Symbian OS form v9.1 is very close to be "Closed OS" (pan intended). If application use any "capability"(for example camera API) - any but most basic functions, it should be signed - endorsed by "test house", which have license from Symbian itself. Third party applications still possible, but only from certified developers. So if Symbian v9.1 will be any success there will probably be more closed OS in future.

  24. Seems to be a matter of reading 'man fstab' ... by PaulBu · · Score: 4, Informative

    ... pay particular attention to noexec flag -- yes, one can configure his/her generic U**x system not to be able to execute anything off "other media" (including home directories) for what, like, 20 years... ;-)

    Amazing what those guys back then thought of, is not it?

    Paul B.

    1. Re:Seems to be a matter of reading 'man fstab' ... by mattyrobinson69 · · Score: 2, Insightful

      Although you can workaround this: /lib/ld-linux.so.2 /noexec/mounted/partition/escalate_to_root

      or more likely: /lib/ld-linux.so.2 /usr/local/bin/ksolitaire

    2. Re:Seems to be a matter of reading 'man fstab' ... by Anonymous Coward · · Score: 2, Informative
      (Lex Luthor) WRONG!

      from man mount:

      (Until recently it was possible to run binaries anyway using a command like /lib/ld*.so /mnt/binary. This trick fails since Linux 2.4.25 / 2.6.0.)
  25. Re:not quite! by LLuthor · · Score: 2, Interesting

    /lib/ld-linux.so /home/me/whatever/binary

    glibc needs a rewrite before noexec becomes useful.

    --
    LL
  26. Re:not quite! by ocelotbob · · Score: 5, Informative

    SELinux policies. You can configure SELinux to have a default deny to execute files that aren't on an approved list of executables, and also ensure that only trusted persons have access to change those files.

    --

    Marxism is the opiate of dumbasses

  27. This is EXACTLY where my mind went! by thecampbeln · · Score: 2, Interesting
    If you want what the poster suggest, you'd pretty much have an XBox/PS2/etc with a keyboard.

    One of the many, MANY hazards with this would be having to buy a supported printer, supported network card, etc... as 3rd party software (and there by hardware) is excluded by definition.

    As another poster has mentioned, wouldn't a LiveCD suffice?

    --
    "1984" was ment to be a warning, not a guidebook. You hear that Kim Jong-il!? BushCo?!
  28. Re:not quite! by OmegaBlac · · Score: 2, Informative
    As was stated before and if you bothered to read the man page for mount you would realize that this problem has been resolved--a few years ago! From mount man page:
    (Until recently it was possible to run binaries anyway using a command like /lib/ld*.so /mnt/binary. This trick fails since Linux 2.4.25/2.6.0.)
    Please stop spreading outdated information.