Crate random

A cryptographically secure source of randomness.

The randomness is provided by a global, cryptographically secure pseudorandom number generator. More specifically, rand_chacha::ChaCha20Rng.

The CSPRNG is instantiated using lazy_static and hence it is initialized lazily on the first request for randomness. It attempts to obtains a seed from the following sources in order:

• RDSEED
• RDRAND
• TSC

An error will be logged if the TSC is used as it is not a high quality source of randomness.

If a consumer requires one-off randomness, next_u32, next_u64, or fill_bytes should be used. Otherwise, init_rng should be used to seed a local PRNG, which can then be used as a source of randomness. Using a local PRNG avoids contention on the global CSPRNG and allows for PRNGs better suited for the task (e.g. non-crypto PRNGs).

Structs

• Error
  Error type of random number generators

Functions

• fill_bytes
  Fills dest with random data.
• init_rng
  Initialises a T RNG.
• next_u32
  Returns a random u32.
• next_u64
  Returns a random u64.