burrow/third_party/rustls-fork-shadow-tls/src/rand.rs
2026-06-05 10:33:41 -07:00

30 lines
875 B
Rust

use crate::msgs::codec;
/// The single place where we generate random material
/// for our own use. These functions never fail,
/// they panic on error.
use ring::rand::{SecureRandom, SystemRandom};
/// Fill the whole slice with random material.
pub(crate) fn fill_random(bytes: &mut [u8]) -> Result<(), GetRandomFailed> {
SystemRandom::new()
.fill(bytes)
.map_err(|_| GetRandomFailed)
}
/// Make a Vec<u8> of the given size
/// containing random material.
pub(crate) fn random_vec(len: usize) -> Result<Vec<u8>, GetRandomFailed> {
let mut v = vec![0; len];
fill_random(&mut v)?;
Ok(v)
}
/// Return a uniformly random u32.
pub(crate) fn random_u32() -> Result<u32, GetRandomFailed> {
let mut buf = [0u8; 4];
fill_random(&mut buf)?;
codec::decode_u32(&buf).ok_or(GetRandomFailed)
}
#[derive(Debug)]
pub struct GetRandomFailed;