1 /*
2  * Copyright (C) 2022 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 //! Trusty implementation of `kmr_common::crypto::Rng`.
17 use crate::ffi_bindings::trusty_rng_add_entropy;
18 use kmr_common::crypto;
19 
20 /// [`crypto::Rng`] implementation for Trusty.
21 #[derive(Default)]
22 pub struct TrustyRng;
23 
24 impl crypto::Rng for TrustyRng {
add_entropy(&mut self, data: &[u8])25     fn add_entropy(&mut self, data: &[u8]) {
26         trusty_rng_add_entropy(data);
27     }
fill_bytes(&mut self, dest: &mut [u8])28     fn fill_bytes(&mut self, dest: &mut [u8]) {
29         openssl::rand::rand_bytes(dest).unwrap(); // safe: BoringSSL's RAND_bytes() never fails
30     }
31 }
32