Struct CtrDrbg

pub struct CtrDrbg<'a, RNG: RngCore + CryptoRng, D: DerefMut<Target = RNG>> { /* private fields */ }

CTR_DRBG pseudorandom generator

Cryptographically secure pseudorandom number generator (CSPRNG). The Mbed TLS implementation of CTR_DRBG which uses AES-256 (default) or AES-128.

Use this if:

• your RNG source isn’t suitable for generating sufficient amounts of cryptographically secure random numbers (e.g. your RNG isn’t fast enough)
• if you do not have a true hardware RNG and want to use it as an RNG initialized with a user-supplied (fixed) seed (use the personalization_string then); it should be obvious that a non-random seed does not yield true random numbers and that reusing the same seed undermines security
• if you want to augment your RNG with another source of entropy (again, use the personalization_string)

This type is a wrapper around the mbedtls_ctr_drbg_context

Implementations

impl<'a, RNG: RngCore + CryptoRng> CtrDrbg<'a, RNG, &'a mut RNG>

pub fn new( entropy_source: &'a mut RNG, personalization_string: Option<&'a [u8]>, ) -> Result<Self, Error>

Initialize and seed a CtrDrbg context

Might fail when no entropy can be collected.

When the alloc feature is activated, the new_with_heap_rng constructor can be used to pass an owned entropy source which will be moved to the heap. This enables you to freely move the CtrDrbg together with the context.

Example

use embedded_mbedtls::rng::CtrDrbg;
use rand_core::RngCore;

let mut entropy_src = rng;

let mut ctr_drbg = CtrDrbg::new(&mut entropy_src, None).unwrap();

let _random = ctr_drbg.next_u32();

Trait Implementations

impl<R: RngCore + CryptoRng, D: DerefMut<Target = R>> Drop for CtrDrbg<'_, R, D>

fn drop(&mut self)

Executes the destructor for this type.

impl<RNG: RngCore + CryptoRng, D: DerefMut<Target = RNG>> RngCore for CtrDrbg<'_, RNG, D>

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<RNG: RngCore + CryptoRng, D: DerefMut<Target = RNG>> CryptoRng for CtrDrbg<'_, RNG, D>