Piecing together slivers of evidence
I’ll be the token idiot today and admit to forgetting a passcode. It’s a fairly important one, and it’s not one I can reset without personally crucifying myself in front of an Apple Genius Bar.
At least forgetting this passcode is not a permanent loss like misplacing encryption keys would be.
See, about the same time the world clinched its collective security sphincter over concerns of government surveillance, I set a genuinely complicated firmware passcode on my Mac.
And then I forgot it. Well, most of it.
I recall enough of the algorithm I use to construct complicated passcodes to have generated a list of five-dozen possibilities, yet not one of them works.
The best part of my total loss of credibility as an IT professional is that no one will ever be able to successfully torture **this** passcode out of me! Others, maybe so.
Nevertheless, my snooping government — or any other attacker — could still use whatever magic tool Apple has to reset the firmware. I don’t have this tool. Surely, the spooks at the NSA, FBI, and CIA do.
Despite it not being a 100-percent infallible lock for your computer, the firmware passcode **is** a valuable protection tool to set. It adds a level of security aimed to complicate the lives of thieves and attackers. It purposefully leaves your default operating system unlocked and instead locks down alternative boot methods.
This means your computer will boot just fine without you needing to type a complicated gate key every time you power up. But, if you want to use your computer in target disk mode, or if you want to boot to an external drive and run a series of hacking — or “recovery” tools — you’ll need the firmware passcode to do so.
With the passcode set, a thief won’t be able to restore your Mac to a usable state, and maybe an attacker will be hard-pressed to break into your wholly-encrypted disk. It’s a layer of security I definitely recommend you establish on your Mac.
Just don’t forget the passcode.
I even wrote mine on a scrap of paper and practiced typing it, fully knowing the implications of forgetting it! But, I also feared the implications of having a written passcode!
And so, right before my brain made long-term out of what was short-term, I shredded that scrap of paper. And I gave the already full bucket of shreds a good toss with my hands just to obfuscate the evidence even more!
Today, I’m digging through that bucket of shreds, piecing together every sliver of the passcode I can find.
It reminds me of a scene from Ben Afflec’s Argo. In a dramatic retelling of the Iran Hostage Crisis, young children rebuild the identities of six U.S. diplomats by sifting through piles and piles of the CIA’s shreded documents. I find that it’s an incredibly tedious and yet surprisingly rewarding way to spend my morning.
It does beat going to the Genius Bar for help, and it definitely beats doing laundry. Also, it’s a testament to the facade of security we place on document shredders!
I mean, after only an hour of intense sifting and picking, I recover three-dozen, eighth-inch wide strips of ruled paper. Ten of the strips show signs of writing. And when lain out on a cutting board, they reconstruct 70-percent of the passcode.
A more-thorough search would turn up additional bits, but at this point, laundry is starting to look appealing.
Once again, I’m relegated to guessing.
I start with a new piece of paper, methodically writing out the possibilities. A few slivers from the shredded scrap confirm portions of the forgotten key, yet the missing bits are unfortunately the same bits I forgot in the first place.
Even worse, the recovered key looks terribly similar to one of the original guessed permutations that failed to unlock the computer earlier. On the third try, the gate opens. A monochromatic Apple logo appears, and the recovery console loads.
Yes, the key is one I tried before. I must have fat-fingered it in my frantic state.
Please let my experience be a lesson to you.
- Remember your passcodes
- Don’t rely on shredders to protect your private data
- Do laundry