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Computer Security - Protecting the Operating System |
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#1 |
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Hello,
I have just come to the conclusion that the only way to protect the machine with free physical access to anauthorized personnel is... to encrypt it. Unfortunately it seems that this can be done only the lonely by DriveCrypt software which costs a lot. It's wonderful stuff indeed allowing to encrypt the drive with authentication feature at the pre-boot level! The encryption seems excellent AES-256 algotithm. It's only drawback (except for the price) is that it doesn't see Linux partitions (not to mention that it doesn't run on Linux)which makes them liable to potential attack. It looks like for now only Windows operationg system may be securely locked unless you run Linux as a VMware guest system on the DriveCrypted Windows host. I wonder what are your experiences with respect to securing the stand alone box with uncontrolled physical access, like at the University (my case). P.S. Have just noticed free stuff called CompuSec PC Security Suite which seems both Windows and Linux compatible though as compared to DriveCrypt it uses weaker encrypting algorithm AES-128 and looks like is much slower. I cannot wait to hear your comments. Kindest regards, -- Ricardo Ricardo |
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#2 |
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"Ricardo" <> wrote in message
news:c6eac$4516d82a$57cf8a7f$. .. > Hello, > I have just come to the conclusion that the only way to protect the > machine > with free physical access to anauthorized personnel is... to encrypt > it. > Unfortunately it seems that this can be done only the lonely by > DriveCrypt > software which costs a lot. It's wonderful stuff indeed allowing to > encrypt > the drive with authentication feature at the pre-boot level! The > encryption > seems excellent AES-256 algotithm. It's only drawback (except for > the price) > is that it doesn't see Linux partitions (not to mention that it > doesn't run > on Linux)which makes them liable to potential attack. It looks like > for now > only Windows operationg system may be securely locked unless you run > Linux > as a VMware guest system on the DriveCrypted Windows host. I wonder > what are > your experiences with respect to securing the stand alone box with > uncontrolled physical access, like at the University (my case). > P.S. Have just noticed free stuff called CompuSec PC Security Suite > which > seems both Windows and Linux compatible though as compared to > DriveCrypt it > uses weaker encrypting algorithm AES-128 and looks like is much > slower. I > cannot wait to hear your comments. > Kindest regards, > -- > Ricardo > Explain how encrypting your hard drive using an MBR bootstrap program replacement will protect the OS and any files. It doesn't. The purpose of boot-time encryption is to prevent someone from *stealing* the information from the hard drive. Once you boot past the encryption authentication, obviously the OS must be usable to the user which means files can be written. Once you're in, you're in and can modify the files. The purpose is not to let in a thief in the first place. |
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#3 |
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"Ricardo" <> wrote in
news:c6eac$4516d82a$57cf8a7f$: > Hello, > I have just come to the conclusion that the only way to protect the > machine with free physical access to anauthorized personnel is... to > encrypt it. Unfortunately it seems that this can be done only the > lonely by DriveCrypt software which costs a lot. It's wonderful stuff > indeed allowing to encrypt the drive with authentication feature at > the pre-boot level! The encryption seems excellent AES-256 algotithm. > It's only drawback (except for the price) is that it doesn't see Linux > partitions (not to mention that it doesn't run on Linux)which makes > them liable to potential attack. It looks like for now only Windows > operationg system may be securely locked unless you run Linux as a > VMware guest system on the DriveCrypted Windows host. I wonder what > are your experiences with respect to securing the stand alone box with > uncontrolled physical access, like at the University (my case). > P.S. Have just noticed free stuff called CompuSec PC Security Suite > which seems both Windows and Linux compatible though as compared to > DriveCrypt it uses weaker encrypting algorithm AES-128 and looks like > is much slower. I cannot wait to hear your comments. > Kindest regards, Free Compusec works fine and is not discenibly slower than any other full HD OTFE encryption product (the hit from any of them is negligible on a fast machine). I wouldn't worry about AES-128, it's more than strong enough. In fact, it is rare for a user to have a password/passphrase that comes anywhere close to 128-bit equivalence - the password, not the encryption, is usually the weakest link. Regards, |
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#4 |
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Ricardo,
There are a dozen or so full/whole disc encryption solutions available with pre-boot authentication option. See the URL below for list: http://www.full-disc-encryption.com/...ncryption.html I use CompuSec. It is free and has support for Linux. It has pre-boot authentication and has a builting credential manager. One thing that is missing support for Trusted Platform Module (TPM). TPM can make the key recovery possible and simplify single sign on. You might also want to take a look at hardware based Full Disc Encryption. There are few vendors that provide that. The above URL lists a few. Hardware based FDE works regardless of the OS you are using. If you are using a notebook Ce-Infosys has PCMCIA card or Seagate Technology will soon have FDE HDD for notebooks: http://www.seagate.com/docs/pdf/mark...400_fde_bb.pdf Also check out the Wikipedia article about Full Disc Encryption: http://en.wikipedia.org/wiki/FDE It talks about "Full disk encryption vs. file or directory encryption" P.S. If you have any feedback about DriveCrypt, please do send it to me. I am looking to buy that product as well. Ricardo wrote: > Hello, > I have just come to the conclusion that the only way to protect the machine > with free physical access to anauthorized personnel is... to encrypt it. > Unfortunately it seems that this can be done only the lonely by DriveCrypt > software which costs a lot. It's wonderful stuff indeed allowing to encrypt > the drive with authentication feature at the pre-boot level! The encryption > seems excellent AES-256 algotithm. It's only drawback (except for the price) > is that it doesn't see Linux partitions (not to mention that it doesn't run > on Linux)which makes them liable to potential attack. It looks like for now > only Windows operationg system may be securely locked unless you run Linux > as a VMware guest system on the DriveCrypted Windows host. I wonder what are > your experiences with respect to securing the stand alone box with > uncontrolled physical access, like at the University (my case). > P.S. Have just noticed free stuff called CompuSec PC Security Suite which > seems both Windows and Linux compatible though as compared to DriveCrypt it > uses weaker encrypting algorithm AES-128 and looks like is much slower. I > cannot wait to hear your comments. > Kindest regards, > -- > Ricardo |
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#5 |
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Vanguard wrote:
> Explain how encrypting your hard drive using an MBR bootstrap program > replacement will protect the OS and any files. It doesn't. The Sure it does. By encrypting them. > purpose of boot-time encryption is to prevent someone from *stealing* > the information from the hard drive. Once you boot past the > encryption authentication, obviously the OS must be usable to the user Where in the poster's question did you see anything that would indicate he was wanting to do anything else? In fact the notable mention of wide open physical access more or less tells us he's trying to secure a machine that might be stolen or tampered with while he's not around, and the machine is off. > which means files can be written. Once you're in, you're in and can > modify the files. The purpose is not to let in a thief in the first > place. Yeah. That's the whole idea behind whole disk encryption. To keep people with physical access from "getting in in the first place". And it's the best protection there is in this scenario. |
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#6 |
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Użytkownik "Ricardo" <> napisał w wiadomo¶ci
news:c6eac$4516d82a$57cf8a7f$. .. > ... Thank you guys so much for your comments. They will help a lot. Kindest regards, Ricardo |
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#7 |
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"Anonyma" <anon-> wrote in message
news:... > Vanguard wrote: > >> Explain how encrypting your hard drive using an MBR bootstrap >> program >> replacement will protect the OS and any files. It doesn't. The > > Sure it does. By encrypting them. > >> purpose of boot-time encryption is to prevent someone from >> *stealing* >> the information from the hard drive. Once you boot past the >> encryption authentication, obviously the OS must be usable to the >> user > > Where in the poster's question did you see anything that would > indicate > he was wanting to do anything else? In fact the notable mention of > wide > open physical access more or less tells us he's trying to secure a > machine that might be stolen or tampered with while he's not around, > and the machine is off. > >> which means files can be written. Once you're in, you're in and >> can >> modify the files. The purpose is not to let in a thief in the >> first >> place. > > Yeah. That's the whole idea behind whole disk encryption. To keep > people with physical access from "getting in in the first place". > And > it's the best protection there is in this scenario. > The subject says the OP is trying to protect the operating system. Excuse me, but why does the OP care since anyone can purchase or obtain a copy of the OS? I read "free physical access to anauthorized personnel" meaning the malcontents actually have *access* to the OS or data files, not simply that they can manage to leave a fingerprint on the case. The OP could use a BIOS password and padlock the case (to protect the BIOS settings, and some laptops don't even need to protect against physical entry) if that's all he wanted to do to restrict physical access *inside* the box (and not preventing instrusion means I can get around your encryption by altering the hardware inside by letting it read the unencrypted data after the cold file system has been decrypted after boot). It doesn't sound like the OP was particularly concerned about losing his laptop/desktop when travelling but protecting his *data* wherever he happens to leave the computer lying around. Well, why couldn't someone then load their own MBR bootstrap program that moves out the original one (used for security)? That is, they simply chain the original bootstrap program onto their own (by, perhaps, moving the original MBR bootstrap program into the rest of the unused first track). While the malware that runs under the OS can't get at the bootstrap password to decrypt the hard drive, the replacement MBR bootstrap can. If you want real security, you need to have it BEFORE you or the BIOS even touch the hard drive (or any other drive or storage device). Does CompuSec or DriveCrypt protect against the MBR bootstrap area getting usurped (just like they usurped it) and getting chained so the authentication used for decryption cannot be captured? Obviously if physically access isn't restricted than something could be installed inside the box that runs even before the MBR bootstrap program gets loaded. There is no point in protecting the OS from theft as it is readily available elsewhere. There is no point in protecting the applications (unless they are your projects). Both can be readily obtained elsewhere than from your piddly laptop so encrypting them is just stupid because it is a waste of performance. If the OP really means that they want to hide their data by encrypting it, then TrueCrypt would be sufficient, and it's free. Why incur the performance penalty of decryption on the OS when its just the data files that need to be protected? Plus you're not screwed over by the security product usurping the MBR bootstrap program that perhaps you would like to use for a multiboot manager. As I recall, Safeboot was the only one that would chain the original MBR bootstrap program after it usurped that spot while all the others simply step atop the MBR bootstrap area. |
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#8 |
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Vanguard wrote:
> "Anonyma" <anon-> wrote in message > news:... > > Vanguard wrote: > > > >> Explain how encrypting your hard drive using an MBR bootstrap > >> program > >> replacement will protect the OS and any files. It doesn't. The > > > > Sure it does. By encrypting them. > > > >> purpose of boot-time encryption is to prevent someone from > >> *stealing* > >> the information from the hard drive. Once you boot past the > >> encryption authentication, obviously the OS must be usable to the > >> user > > > > Where in the poster's question did you see anything that would > > indicate > > he was wanting to do anything else? In fact the notable mention of > > wide > > open physical access more or less tells us he's trying to secure a > > machine that might be stolen or tampered with while he's not around, > > and the machine is off. > > > >> which means files can be written. Once you're in, you're in and > >> can > >> modify the files. The purpose is not to let in a thief in the > >> first > >> place. > > > > Yeah. That's the whole idea behind whole disk encryption. To keep > > people with physical access from "getting in in the first place". > > And > > it's the best protection there is in this scenario. > > > > > The subject says the OP is trying to protect the operating system. > Excuse me, but why does the OP care since anyone can purchase or > obtain a copy of the OS? Why would you believe "stealing" the operating system is the only threat. Far more likely scenario is wanting to keep people from tampering with the copy you have installed. A good way to do that is to prevent anyone from accessing it when nobody is around. Make it impossible to even boot the machine, or access the drive with the OS on it. Whole disk encryption is the best way to do that. > I read "free physical access to anauthorized > personnel" meaning the malcontents actually have *access* to the OS or > data files, Then you're misreading things or assuming way too much. Physical access means just that. They have the ability to lay hands on the equipment. It doesn't mean a single thing about access to data, you're just assuming the equipment is left on 24/7. > It doesn't sound like the OP was particularly concerned about losing > his laptop/desktop when travelling but protecting his *data* wherever Yes. And encrypting it is the best way to do that outside a hardened bunker and armed guards. In many ways it's more secure than even that. > he happens to leave the computer lying around. Well, why couldn't > someone then load their own MBR bootstrap program that moves out the > original one (used for security)? That is, they simply chain the Because the whole disk is encrypted. Replacing the MBR just makes the whole drive inaccessible even *with* proper authentication. Did you really believe that whole disk encryption could be circumvented by swapping MBR's, or maybe booting from another device?? Wow... |
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#9 |
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Anonyma wrote:
> Vanguard wrote: > >> Explain how encrypting your hard drive using an MBR bootstrap program >> replacement will protect the OS and any files. It doesn't. The > > Sure it does. By encrypting them. No, it doesn't. I can simply overwrite the hard drive with garbage and all files are gone. >> purpose of boot-time encryption is to prevent someone from *stealing* >> the information from the hard drive. Once you boot past the >> encryption authentication, obviously the OS must be usable to the user > > Where in the poster's question did you see anything that would indicate > he was wanting to do anything else? In fact the notable mention of wide > open physical access more or less tells us he's trying to secure a > machine that might be stolen or tampered with while he's not around, > and the machine is off. A non-tamper-resistent machine is trivially tampered to reveal everything. The simplest and most obvious method is to modify the bootloader to store the entered key additionally to its normal functions - that's why you should keep on a separate media. Then, ranging from modifying the BIOS (pretty easy) to reading data directly from RAM (FireWire, PCI, PCMCIA) and keyloggers (put between your keyboard and the keyboard connector) up to directly updating the CPU's microcode, everything else will be successful. >> which means files can be written. Once you're in, you're in and can >> modify the files. The purpose is not to let in a thief in the first >> place. > > Yeah. That's the whole idea behind whole disk encryption. To keep > people with physical access from "getting in in the first place". And > it's the best protection there is in this scenario. Beside that, what exactly would someone try if the OS boots without invention to a login screen where the password is unknown? I can't see how someone should be able to write files at this point. |
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#10 |
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Sebastian Gottschalk wrote:
> Anonyma wrote: > > > Vanguard wrote: > > > >> Explain how encrypting your hard drive using an MBR bootstrap program > >> replacement will protect the OS and any files. It doesn't. The > > > > Sure it does. By encrypting them. > > No, it doesn't. I can simply overwrite the hard drive with garbage and all > files are gone. What a meaningless drizel of semantic idiocy... "a watermelon can't fly an airplane so it's no good for painting your house...". Oh, and you're replying to posters you've claimed to have killfiled again ya' pathetic loser. <rest snipped unread> |
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