blob: 12f28c519de3dc7535dfd02705b3c9d66dafbd94 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
use core::ops::{Deref, DerefMut};
use core::ptr;
use core::sync::atomic;
use super::error::Error;
/// A seed, which a key pair can be derived from.
#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
pub struct Seed([u8; Seed::BYTES]);
impl From<[u8; 32]> for Seed {
fn from(seed: [u8; 32]) -> Self {
Seed(seed)
}
}
impl Seed {
/// Number of raw bytes in a seed.
pub const BYTES: usize = 32;
/// Creates a seed from raw bytes.
pub fn new(seed: [u8; Seed::BYTES]) -> Self {
Seed(seed)
}
/// Creates a seed from a slice.
pub fn from_slice(seed: &[u8]) -> Result<Self, Error> {
let mut seed_ = [0u8; Seed::BYTES];
if seed.len() != seed_.len() {
return Err(Error::InvalidSeed);
}
seed_.copy_from_slice(seed);
Ok(Seed::new(seed_))
}
/// Tentatively overwrite the content of the seed with zeros.
pub fn wipe(self) {
Mem::wipe(self.0)
}
}
#[cfg(feature = "random")]
impl Default for Seed {
/// Generates a random seed.
fn default() -> Self {
let mut seed = [0u8; Seed::BYTES];
getrandom::getrandom(&mut seed).expect("RNG failure");
Seed(seed)
}
}
#[cfg(feature = "random")]
impl Seed {
/// Generates a random seed.
pub fn generate() -> Self {
Seed::default()
}
}
impl Deref for Seed {
type Target = [u8; Seed::BYTES];
/// Returns a seed as raw bytes.
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl DerefMut for Seed {
/// Returns a seed as mutable raw bytes.
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.0
}
}
pub(crate) struct Mem;
impl Mem {
#[inline]
pub fn wipe<T: Default>(mut x: impl AsMut<[T]>) {
let x = x.as_mut();
for i in 0..x.len() {
unsafe {
ptr::write_volatile(x.as_mut_ptr().add(i), T::default());
}
}
atomic::compiler_fence(atomic::Ordering::SeqCst);
atomic::fence(atomic::Ordering::SeqCst);
}
}
|