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Joined 19 days ago
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Cake day: May 10th, 2025

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  • Very interesting thanks for the explanation.

    I think that makes some sense to me. I’m moderately familiar with signatures and encryption. I’m going to do some more research into blind signatures now since that’s one thing I have never had to implement.

    Without doing that research, I still feel that the bank or whatever could store the signature info at the time of signing with the account that requested it, but perhaps the blind signing even protects against that if the verification process is done in some way that the original signing request info isn’t present in the same form.

    Anyway, thanks for the response!

    ETA:

    Oh the other hole in the ATMs I was talking about assuming a malicious ATM. Since the coin can only be verified by depositing it, (without doing more research on this) I still don’t see a way to verify that the ATM actually gave you a valid signature. Maybe it’s possible to validate the signature before unwrapping the coin, then impossible to validate the unwrapped coin that is given to the merchant. I could see that.

    Also presumably these could be bank ATMs and not sketchy Bitcoin ATMs so maybe the malicious case isn’t as much to worry about.




  • ARM has bit-banding specifically for this. I think it’s limited to M-profile CPUs (e.g. v7-M) but I’ve definitely used this before. It basically creates a 4-byte virtual address for every bit in a region. So the CPU itself can’t “address” a bit but it can access an address backed by only 1 bit of SRAM or registers (this is also useful to atomically access certain bits in registers without needing to use SW atomics).