Crate tc_misc_block_cipher 

Less common block ciphers on the tc_block_cipher traits, ported from Bouncy Castle, one Cargo feature each and none on by default. Each feature adds a module of the same name:

• idea: IDEA, with a 128-bit key and a 64-bit block.
• noekeon: Noekeon in direct-key mode, with a 128-bit key and block.
• rijndael: Rijndael with 128- to 256-bit blocks and keys.
• skipjack: SKIPJACK, with an 80-bit key and a 64-bit block.
• tea: TEA and XTEA, with a 128-bit key and a 64-bit block.

Timing

Noekeon, TEA and XTEA are constant time with respect to key and block contents: they use only additions, bitwise operations and fixed shifts or rotations. IDEA, Rijndael and SKIPJACK are variable time: IDEA’s multiplication branches on secret values and its decryption key setup runs a key-dependent Euclidean loop, Rijndael and SKIPJACK look up tables with secret data, and Rijndael’s field multiplication branches on it. Use them only where timing leakage is outside the threat model.

Stored schedules are wiped on replacement and drop, but caller buffers and every register or stack copy are not. No mode, padding or authentication is provided.

Example

XTEA, with the tea feature:

use tc_block_cipher::{BlockCipher, BlockCipherInit, CipherDirection, KeyRef};
use tc_misc_block_cipher::tea::{BLOCK_BYTES, KEY_BYTES, XteaEngine};

let key = [0x42; KEY_BYTES];
let mut engine = XteaEngine::new();
engine.init(CipherDirection::Encrypt, &KeyRef::new(&key)).unwrap();
let mut ciphertext = [0; BLOCK_BYTES];
assert_eq!(
    engine.process_block(&[0x11; BLOCK_BYTES], &mut ciphertext),
    Ok(BLOCK_BYTES)
);

Modules

idea

IDEA single-block encryption with 128-bit keys and 64-bit blocks.

noekeon

Noekeon single-block encryption in direct-key mode.

rijndael

Generalized Rijndael single-block ciphers.

skipjack

SKIPJACK single-block encryption with an 80-bit key and 64-bit blocks.

tea

TEA and XTEA single-block ciphers with big-endian key and block words.