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Earlier quoted context omitted.
Not at all.
Why not? If the data is zeroed, there wouldn't be anything to find by forensics.
I don't think this is a good way to initiate the destruction. Washing hands, sweating, condensation from beverages, etc. could easily trigger this.
But you want to trigger it, to keep the data safe. Though if the adversary has sweaty fingers they also get your data.
This could be implemented by writing a timestamp file on wakeup.
With the Big Red Switch that throws sparks and emits smoke, the adversary may still inflict punishment on you, but they have no illusions that they can torture you into revealing "the secret way to access it".
Does this actually prevent forensics from finding any data?
If you do this as part of a legal search and they catch on you're now in a lot more trouble and you've caught their attention.
But really, apart from the novelty, why attempt to destroy the chip in the first place? Encrypt the bulk flash memory, store the key in supercap backed SRAM, and then zero out and short the RAM when triggered. Then you'd have a reusable device in case of inadvertent triggering. You could even load it with a key from a trusted host computer (stored on the computer or derived from passphrase), gain safety for transporting your files while walking around and plugging in to less trusted computers), and then if you did accidentally trigger the device, simply reload the key afterwards when you got back to the trusted computer and not have to rewrite the flash. The utility of such reloading functionality would depend on your threat model, but could be very useful for a lot of people. Perhaps border crossings.
Since we're on the topic of bespoke crypto ideas, I've often mused about the possibility of a probabilistic KDF that would take a lengthy amount of time to derive the key, and/or be resilient to typos in the passphrase. Rather than doing a fixed number of rounds that take a few seconds to derive the key xor failure, there would be additional random bits that had to be derived via hash collision finding, stretching out the time. Such a thing could be resistant to typos or omissions of words in the passphrase, with the result that such errors would increase the time even more. Thus, until the KDF reported success, an attacker would not know whether you gave them the correct passphrase and they just need more time, or whether you were stalling.
Better off with a strong shallow field, high intensity rare earth magnet attenuated by a removable stainless steel shield that erases the data only if the USB key is removed from a holster incorrectly, thereby removing the stainless steel shield.
Earlier quoted context omitted.
But you want to trigger it, to keep the data safe. Though if the adversary has sweaty fingers they also get your data.
You could use a scheme kind of like how port-knocking works. For example, plugging in directly causes self-destruct, but plug and unplugging twice in 5 seconds will be the "okay it's me" signal. This could be implemented by writing a timestamp file on wakeup.
You’d need to embed a clock and an energy source to keep the clock going.
Earlier quoted context omitted.
Why not? If the data is zeroed, there wouldn't be anything to find by forensics.
From my reading it doesn't appear to zero the data, just overdrive the controller and hope to burn it out, which may or may not have downstream effects on the memory chip itself.
I think Naomi Wu's Big Red Switch Box is better. With a seemingly dead drive, an adversary may still try to rubber-hose an access method out of you on the assumption that there's some special sequence to required to gain access. A simply dead drive is suspect, especially given the prevalence of ideas like port knocking, etc. With the Big Red Switch that throws sparks and emits smoke, the adversary may still inflict p…