block_modes/
ecb.rs

1use crate::{
2    errors::InvalidKeyIvLength,
3    traits::BlockMode,
4    utils::{get_par_blocks, Block},
5};
6use block_padding::Padding;
7use cipher::{
8    generic_array::{
9        typenum::{Unsigned, U0},
10        GenericArray,
11    },
12    BlockCipher, BlockDecrypt, BlockEncrypt, NewBlockCipher,
13};
14use core::marker::PhantomData;
15
16/// [Electronic Codebook][1] (ECB) block cipher mode instance.
17///
18/// Note that `new` method ignores IV, so during initialization you can
19/// just pass `Default::default()` instead.
20///
21/// [1]: https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#ECB
22#[derive(Clone)]
23pub struct Ecb<C: BlockCipher + BlockEncrypt + BlockDecrypt, P: Padding> {
24    cipher: C,
25    _p: PhantomData<P>,
26}
27
28impl<C, P> BlockMode<C, P> for Ecb<C, P>
29where
30    C: BlockCipher + BlockEncrypt + BlockDecrypt,
31    P: Padding,
32{
33    type IvSize = U0;
34
35    fn new(cipher: C, _iv: &GenericArray<u8, U0>) -> Self {
36        Self {
37            cipher,
38            _p: Default::default(),
39        }
40    }
41
42    fn new_from_slices(key: &[u8], _iv: &[u8]) -> Result<Self, InvalidKeyIvLength>
43    where
44        C: NewBlockCipher,
45    {
46        let cipher = C::new_from_slice(key).map_err(|_| InvalidKeyIvLength)?;
47        Ok(Self {
48            cipher,
49            _p: Default::default(),
50        })
51    }
52
53    fn encrypt_blocks(&mut self, blocks: &mut [Block<C>]) {
54        if C::ParBlocks::to_usize() != 1 {
55            let (par_blocks, blocks) = get_par_blocks::<C>(blocks);
56            par_blocks
57                .iter_mut()
58                .for_each(|pb| self.cipher.encrypt_blocks(pb));
59            blocks
60                .iter_mut()
61                .for_each(|pb| self.cipher.encrypt_block(pb));
62        } else {
63            blocks
64                .iter_mut()
65                .for_each(|pb| self.cipher.encrypt_block(pb));
66        }
67    }
68
69    fn decrypt_blocks(&mut self, blocks: &mut [Block<C>]) {
70        if C::ParBlocks::to_usize() != 1 {
71            let (par_blocks, blocks) = get_par_blocks::<C>(blocks);
72            par_blocks
73                .iter_mut()
74                .for_each(|pb| self.cipher.decrypt_blocks(pb));
75            blocks
76                .iter_mut()
77                .for_each(|pb| self.cipher.decrypt_block(pb));
78        } else {
79            blocks
80                .iter_mut()
81                .for_each(|pb| self.cipher.decrypt_block(pb));
82        }
83    }
84}
block_modes/ecb.rs

block_modes/
ecb.rs
