4 ms·

The inclusion of TPM is definitely the most interesting aspect of this to me. I was initially turned off by the idea because I tend to associate them with nasty

The inclusion of TPM is definitely the most interesting aspect of this to me. I was initially turned off by the idea because I tend to associate them with nasty enterprise-y DRM types of stuff. But I wonder why it's included here. Maybe for secure storage of private keys? I'm guessing that's the desired purpose for TPM in a server setting. Obviously I'm not super familiar with TPM. I wonder if it can be used for things like better random number generation or hardware-accelerated hashing. I'm guessing if it supported hashing from userspace, the cryptocurrency crowd would have been all over it already.

simcop2387 5y ago
I believe the 2.0 standard does support rng, but I;m not sure of the specifics. there might be some hashing functionality but the interface is going to be too slow for large data. I think it;s there to do integrity checks for bootloaders and such
megous 5y ago
TPMs are just SPI connected devices. You can add them to any SBC. Hardware accelerated hashing would be severely limited by the SPI bus speed.
duskwuff 5y ago
> I wonder if it can be used for things like better random number generation... Too slow to be useful, and the BCM283x SoC already has an internal RNG: https://github.com/torvalds/linux/blob/master/drivers/char/hw_random/bcm2835-rng.c https://github.com/torvalds/linux/blob/master/drivers/char/h... > ... or hardware-accelerated hashing The TPM is on a really slow bus (33 MHz, 4 bits, tons of wait states). Even without any hardware acceleration, hashing on the CPU is much faster.
- staticassertion 5y ago
  You wouldn't hit a TPM every time you wanted a random number. Your OS would just use it when it wanted to seed its entropy pool. This is particularly useful at boot when entropy is very low.
chokeartist 5y ago
> Maybe for secure storage of private keys? That's the first thing I thought of. Separation of long-term lived [private] key material from the OS / filesystem.

simcop2387 5y ago

I believe the 2.0 standard does support rng, but I;m not sure of the specifics. there might be some hashing functionality but the interface is going to be too slow for large data. I think it;s there to do integrity checks for bootloaders and such

megous 5y ago

TPMs are just SPI connected devices. You can add them to any SBC. Hardware accelerated hashing would be severely limited by the SPI bus speed.

duskwuff 5y ago

> I wonder if it can be used for things like better random number generation... Too slow to be useful, and the BCM283x SoC already has an internal RNG: https://github.com/torvalds/linux/blob/master/drivers/char/hw_random/bcm2835-rng.c https://github.com/torvalds/linux/blob/master/drivers/char/h... > ... or hardware-accelerated hashing The TPM is on a really slow bus (33 MHz, 4 bits, tons of wait states). Even without any hardware acceleration, hashing on the CPU is much faster.

staticassertion 5y ago
You wouldn't hit a TPM every time you wanted a random number. Your OS would just use it when it wanted to seed its entropy pool. This is particularly useful at boot when entropy is very low.

chokeartist 5y ago

> Maybe for secure storage of private keys? That's the first thing I thought of. Separation of long-term lived [private] key material from the OS / filesystem.