Struct rand::EntropyRng

pub struct EntropyRng { /* fields omitted */ }

A generator provided specifically for securely seeding algorithmic generators (PRNGs).

Where possible, EntropyRng retrieves random data from the operating system's interface for random numbers (OsRng); if that fails it will fall back to the JitterRng entropy collector. In the latter case it will still try to use OsRng on the next usage.

If no secure source of entropy is available EntropyRng will panic on use; i.e. it should never output predictable data.

This is either a little slow (OsRng requires a system call) or extremely slow (JitterRng must use significant CPU time to generate sufficient jitter). It is recommended to only use EntropyRng to seed a PRNG (as in thread_rng) or to generate a small key.

Methods

impl EntropyRng

pub fn new() -> Self

Create a new EntropyRng.

This method will do no system calls or other initialization routines, those are done on first use. This is done to make new infallible, and try_fill_bytes the only place to report errors.

Trait Implementations

impl Debug for EntropyRng

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl RngCore for EntropyRng

fn next_u32(&mut self) -> u32

Return the next random u32.

fn next_u64(&mut self) -> u64

Return the next random u64.

fn fill_bytes(&mut self, dest: &mut [u8])

Fill dest with random data.

fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error>

Fill dest entirely with random data.

impl CryptoRng for EntropyRng