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    How to circumvent UEFI secure boot

    http://distrowatch.com/weekly.php?issue=20121126#qa

    Copied in total here as a backup to the original article:
    Secure Boot has arrived

    A few weeks ago one of my computers, a desktop machine, called it quits after many productive years of service. Following a respectful period of mourning, I decided to go out and get myself a new desktop computer. Nothing fancy, just a nice low-end box. I settled on HP's Pavilion P6-2310. The machine arrived in a timely manner, I hooked it up and realized that in my haste to get my shopping over with I had forgotten one important detail: Secure Boot.

    Secure Boot, in case you missed all the excitement earlier, is a technology which is supposed to protect computer users from malware by insuring only trusted software can boot on the machine. How this works is, essentially, the computer comes with a security key (or keys) and any operating system or boot loader which we want to run on the machine needs to have a corresponding key. The idea is malware won't be able to sneak onto the computer and get loaded into memory before the operating system. A side effect, which many do not believe to be a coincidence, is operating systems other than Windows 8 are prevented from booting too. For some reason these details had slipped my mind when I was shopping on-line. When I hooked up the new computer and booted for the first time I was suddenly reminded in an unpleasant way.

    The first symptom was that I could not boot from any device except the hard disk. I was thrown into the Windows 8 set up process. The manuals which came with the computer do not mention, in any fashion, accessing the BIOS/UEFI, changing boot order or disabling Secure Boot. Typically in the past computers have displayed hints, such as "Press F1 to edit settings" or "Press F9 to change boot device" when they power up. Not in this case, no hints are given and we're left to trial and error. F10, I found, would grant me access to the machine's start-up configuration, but getting my thumb drive to boot took a few steps beyond that.

    First I tried to simply change the boot order and was told this was not possible while Secure Boot was enabled. Hunting through the menus I finally found the Secure Boot feature and, selecting it, I was informed (via a big, red warning box) that disabling Secure Boot was dangerous and not recommended. Then I had to disable Secure Boot and re-enabled "Legacy" boot options in the proper order and then, finally, I was able to enable specific devices from which I wanted to boot. After that I was able to boot from my thumb drive only if I knew to hold down F9 while the computer was starting up, we're not given that information.

    In short, to get to the point where we can attempt to boot an alternative operating system we need to know our way through six steps:
    • Boot machine while pressing F10
    • Find Secure Boot in the menu tree, ignore warnings
    • Disable Secure Boot feature
    • Enable legacy boot options
    • Enable specific legacy devices, such as USB devices
    • Save and reboot while holding down F9

    To the more technically minded, this might not seem so bad, but keep in mind these steps are performed without documentation, with no hints and with big warning pop-ups letting the user know what a bad idea disabling Secure Boot is. This is not something the average user is going to know how to do, nor will they likely want to follow through if they read the on-screen messages. This is a problem as much of the growth in the Linux community over the past decade has come from the ease of installing mainstream distributions. Distributions like Fedora and Ubuntu have made setting up a fresh install as simple as "Insert CD -> Click Next -> Next -> Next -> Enter a username and password->Next". Computers with Secure Boot remove that ease of use factor by throwing up hidden options, scary warnings and multiple menu items which must be accessed in a specific order before the user can even get to the "Insert CD" part of the installation process. Certainly, system administrators and more experienced users can work around these barriers, but there is a large portion of the public which is relatively inexperienced and willing to try Linux if it is easy to set up. Secure Boot means Linux is no longer simple to install, or even try, from detachable media.

    Now, you might be thinking, as I was, that it was foolish of me to purchase a machine with Secure Boot in the first place. After all, I've been warning people about it for long enough I should have been more careful. That was what was going through my mind as I went through the long process of getting my thumb drive to be recognized as a boot device. But then, the next day, I went back to the merchant's website and discovered something. There is no mention of Secure Boot, UEFI or Windows 8 certification anywhere on the page. How is a consumer to know, even if they are aware of the feature, whether a machine is locked down or not? Software freedom requires vigilance and I fear that is more true now than it was a year ago. Be careful when shopping for new computers, it is easy to purchase more trouble than one bargained for.
    I still hold to my opinion that the true reason for UEFI is to stall the surge in Linux popularity by significantly increasing its ease of installation. And, of course, the method given above ONLY works IF your UEFI menu allows switching to legacy BIOS.
    "A nation that is afraid to let its people judge the truth and falsehood in an open market is a nation that is afraid of its people.”
    – John F. Kennedy, February 26, 1962.

    #2
    Originally posted by GreyGeek View Post
    I still hold to my opinion that the true reason for UEFI is to stall the surge in Linux popularity by significantly increasing its ease of installation. And, of course, the method given above ONLY works IF your UEFI menu allows switching to legacy BIOS.
    s/UEFI/Secure Boot/
    s/increasing/decreasing/
    Then I agree (who needs to use real words )

    Comment


      #3
      Originally posted by GreyGeek View Post
      http://distrowatch.com/weekly.php?issue=20121126#qaI still hold to my opinion that the true reason for UEFI is to stall the surge in Linux popularity by significantly increasing its ease of installation.
      Shouldn't it be "by significantly decreasing its ease of installation"? (or inhibit, block or just plain make a PITA)

      I think james147 was saying basically the same thing in what looks like a directory, lol. ;-) @ james (I am guessing the 's' stands for 'switch')

      Edit: Now if I were to don my tinfoil conspiracy hat (*adjusts hat*), Ballmer and the gang knew WinDOHS 8 would be a flop on PCs, so..."we'll force it on them, and lock everything else out in the process", (*evil laugh*, *hand wringing*). ;-)

      Edit 2: Correct me if I am wrong but Mr. Riley says UEFI good, Secure Boot bad.
      Last edited by tek_heretik; Dec 07, 2012, 06:15 AM.

      Comment


        #4
        Originally posted by tek_heretik View Post
        Shouldn't it be "by significantly decreasing its ease of installation"?

        I think james147 was saying basically the same thing in what looks like a directory, lol. ;-) @ james (I am guessing the 's' stands for 'switch')
        It's an example of sed (Stream EDitor) syntax; the 's' stands for 'substitute'.

        http://en.wikipedia.org/wiki/Sed
        sigpic
        "Let us think the unthinkable, let us do the undoable, let us prepare to grapple with the ineffable itself, and see if we may not eff it after all."
        -- Douglas Adams

        Comment


          #5
          Originally posted by HalationEffect View Post
          It's an example of sed (Stream EDitor) syntax; the 's' stands for 'substitute'.

          http://en.wikipedia.org/wiki/Sed
          Ah, thank you. :-)

          Comment


            #6
            Originally posted by HalationEffect View Post
            It's an example of sed (Stream EDitor) syntax; the 's' stands for 'substitute'.

            http://en.wikipedia.org/wiki/Sed
            And I believe sed gets it from Perl (where most things get their regex from) it also works in vim and quite a few unix utilities.

            Comment


              #7
              Originally posted by james147 View Post
              And I believe sed gets it from Perl (where most things get their regex from) it also works in vim and quite a few unix utilities.
              No, sed influenced perl. sed pre-dates perl by about 15 years.

              Comment


                #8
                Originally posted by andystmartin View Post
                No, sed influenced perl. sed pre-dates perl by about 15 years.
                Interesting thanks for that

                Comment


                  #9
                  Originally posted by tek_heretik View Post
                  Edit 2: Correct me if I am wrong but Mr. Riley says UEFI good, Secure Boot bad.
                  Yep, that is an accurate assessment of my claims.

                  One of the challenges that people will face is trying to figure out how to disable Secure Boot, as chronicled by the writer at DistroWatch. There is, alas, no industry standard for which function keys to press to enter firmware setup or to interrupt the boot order sequence. On my ThinkPads, the former is F1, while the latter is F12. On my Samsung tablet, the former is Power+VolUp and the latter is F10. Of course, this not exactly a new problem. Plus, for many years, some firmware -- even BIOS -- has concealed the "confusing" boot messages behind a pretty logo screen, so the "Press Fn to..." messages aren't displayed.

                  What's actually troublesome about the story above is that (a) the computer's documentation lacked info on how to enter the firmware setup and (b) the warning screen appears to be guilty of scareifying.

                  And if may quibble a bit with the title of this thread... "circumvent" means to determine a way around the security. That isn't what has happened here. Instead, the DistroWatch writer simply figured out how to disable the feature. Technically, this isn't circumvention. It's indeed unfortunate that discovery of this capability is difficult.

                  Comment


                    #10
                    http://www.h-online.com/open/news/it...x-1761089.html

                    Linux developer Matthew Garrett has released a version of his Shim Secure Boot bootloader that allows any Linux distribution to be launched on Secure Boot systems without the need to disable UEFI Secure Boot. As Garrett's Shim binary has been signed by Microsoft, the Secure Boot bootloader will be executed by almost any type of UEFI firmware.

                    Comment


                      #11
                      Thanks, folks, for catching my finger's typos. I slap them when they do that but they are getting sneaky lately and .... well, you know.
                      "A nation that is afraid to let its people judge the truth and falsehood in an open market is a nation that is afraid of its people.”
                      – John F. Kennedy, February 26, 1962.

                      Comment


                        #12
                        Ah, you just hate UEFI with the heat of a thousand suns and can't get control of your emotions, that's all

                        Comment


                          #13
                          All right, Officer, I confess, I do HATE UEFI, but I didn't try to kill him. He'll kill himself because he's too pushy.
                          "A nation that is afraid to let its people judge the truth and falsehood in an open market is a nation that is afraid of its people.”
                          – John F. Kennedy, February 26, 1962.

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