• 7heo@lemmy.ml
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    9 months ago

    You might be able to drop the manufacturer’s keys somehow[1] but I would not recommend.

    If you still really want to do this, I would advise you to:

    1. Unsolder the eeprom
    2. Solder a slot-in socket instead
    3. Get a new blank chip
    4. Get an eeprom programmer
    5. Dump the eeprom to a bin file
    6. Flash that bin file onto the new eeprom
    7. Test that the motherboard POSTs
    8. Search for cryptographic signatures (possibly compressed, possibly obfuscated - rolling XOR, reversed, etc) in the bin file
    9. Hack around that bin file trying to blank the keys, or better yet, replace them with yours.
    10. Go to step 7, repeat.

    Of course, you could always flash the modified bin onto the new eeprom directly at step 6, but what’s the fun in that? 😅

    Also, if you really do this(!), please don’t forget to document. 🙏


    1. I doubt they went as far as “fusing” them in the factory, it would be perceived as “overkill” for a general public product - which I assume it is - and would run the risk of bricking upgradibility of the board, should the manufacturer lose the keys. Plus, it doesn’t help anything (quite the contrary) if the keys are somehow leaked by the manufacturer. ↩︎

    • quaff@lemmy.ca
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      9 months ago

      Welp. My skills end at #1. So I guess I’m SOL 😂 Thanks for this though! I like knowing that it’s possible, even if it’s outside of my current ability 🙂

      • 7heo@lemmy.ml
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        9 months ago

        Well, technically, if you can do #1, you can probably do #2… 😋

        And then the rest doesn’t require advanced skills, with the exceptions of point #8. Using a programmer is essentially the same as with any other tool. There is a method, you follow it, and you never, ever get close to the blade with your hands when the machine is running. Oh, no, wait, that is for a different tool. 🙃

        • quaff@lemmy.ca
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          9 months ago

          For sure haha I meant I don’t have soldering skills. I know there’s a hardware BIOS programmer device I could get, but I feel like at that point, I may as well get a new motherboard 👀

          • BeardedGingerWonder@feddit.uk
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            9 months ago

            If you’re getting a new motherboard anyway you might as well give it a go. There are some micro soldering training kits you can pick up for ~£15 to practice.