1//! The single place where we generate random material for our own use.
2
3use alloc::vec;
4use alloc::vec::Vec;
5
6use crate::crypto::SecureRandom;
7
8/// Make a [`Vec<u8>`] of the given size containing random material.
9pub(crate) fn random_vec(
10 secure_random: &dyn SecureRandom,
11 len: usize,
12) -> Result<Vec<u8>, GetRandomFailed> {
13 let mut v: Vec = vec![0; len];
14 secure_random.fill(&mut v)?;
15 Ok(v)
16}
17
18/// Return a uniformly random [`u32`].
19pub(crate) fn random_u32(secure_random: &dyn SecureRandom) -> Result<u32, GetRandomFailed> {
20 let mut buf: [u8; 4] = [0u8; 4];
21 secure_random.fill(&mut buf)?;
22 Ok(u32::from_be_bytes(buf))
23}
24
25/// Return a uniformly random [`u16`].
26pub(crate) fn random_u16(secure_random: &dyn SecureRandom) -> Result<u16, GetRandomFailed> {
27 let mut buf: [u8; 2] = [0u8; 2];
28 secure_random.fill(&mut buf)?;
29 Ok(u16::from_be_bytes(buf))
30}
31
32/// Random material generation failed.
33#[derive(Debug)]
34pub struct GetRandomFailed;
35