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Peer-to-peer cloud environment
https://wetware.run
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Use cryptographic PRNG with `WithRandSource` option #106

Closed lthibault closed 1 year ago

lthibault commented 1 year ago

I just realized that WithRandSource maps onto crypto/rand, not math/rand.

Wazero is quite strict about not letting guest code make syscalls, so the value defaults to a (deterministic) stub. We definitely want to provide guests with crypto-grade entropy, so two questions:

  1. What is the benefit (if any) of providing per-instance/isolated random readers?
  2. If there is a benefit, how can we implement a stand-alone io.Reader that is suitable for crypto? (Maybe a stream cipher seeded with crypto/rand?)
lthibault commented 1 year ago

cc #103

lthibault commented 1 year ago

https://security.stackexchange.com/questions/86430/linux-kernel-entropy-does-it-matter-to-dev-urandom-and-what-is-a-minimum#86432

This has reassured me that there is no risk in sharing crypto/rand.Reader across many processes, at least from an entropy-depletion point of view.

At this point, I'm not certain why the Wazero folks have decided not to provide crypto/rand.Reader by default. I should make it a point to ask them.