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
#![no_std]
pub extern crate generic_array;
use generic_array::{GenericArray, ArrayLength};
use generic_array::typenum::Unsigned;
type Block<BlockSize> = GenericArray<u8, BlockSize>;
pub trait BlockCipher {
type BlockSize: ArrayLength<u8>;
fn encrypt_block(&self, block: &mut Block<Self::BlockSize>);
fn decrypt_block(&self, block: &mut Block<Self::BlockSize>);
}
pub trait NewFixKey: BlockCipher {
type KeySize: ArrayLength<u8>;
fn new(key: &GenericArray<u8, Self::KeySize>) -> Self;
}
#[derive(Debug, Copy, Clone, Eq, PartialEq)]
pub struct InvalidKeyLength;
pub trait NewVarKey: BlockCipher + Sized {
fn new(key: &[u8]) -> Result<Self, InvalidKeyLength>;
}
impl<T: NewFixKey> NewVarKey for T {
fn new(key: &[u8]) -> Result<Self, InvalidKeyLength> {
if key.len() != T::KeySize::to_usize() {
Err(InvalidKeyLength)
} else {
Ok(T::new(GenericArray::from_slice(key)))
}
}
}