RustCrypto: block ciphers

Collection of block ciphers and block modes written in pure Rust.

Warnings

Currently only AES crates provide constant-time implementations. If you do not really know what you are doing it's generally recommended not to use other cipher implementations in this repository.

Additionally crates in this repository have not yet received any formal cryptographic and security reviews.

USE AT YOUR OWN RISK.

Supported algorithms

Name	Alt name	Crate name	crates.io	Docs
AES	Rijndael	aes aesni aes-soft
Blowfish		blowfish
DES + 3DES	DEA + 3DEA	des
Kuznyechik	GOST R 34.12-2015	kuznyechik
Magma	GOST 28147-89 and GOST R 34.12-2015	magma
RC2	ARC2	rc2
Twofish		twofish

Additional crates

Crate name	crates.io	Docs
block-modes

Minimum Supported Rust Version

All crates in this repository support Rust 1.22 or higher. (except aesni and aes crates, which require Rust 1.27) In future minimum supported Rust version can be changed, but it will be done with the minor version bump.

Usage

Block cipher crates provide only bare block cipher implementations. For most applications you will need to use some block cipher mode of operation which are generically implemented in the block-modes crate.

Some block modes (CTR, CFB, OFV) transform block ciphers into stream ciphers.Such modes are published under separate crates in the RustCrypto/stream-ciphers repository.

Lets use AES128-CBC with PKCS7 padding to show an example:

#[macro_use] extern crate hex_literal;
extern crate aes_soft as aes;
extern crate block_modes;

use block_modes::{BlockMode, Cbc};
use block_modes::block_padding::Pkcs7;
use aes::Aes128;

// create an alias for convenience
type Aes128Cbc = Cbc<Aes128, Pkcs7>;

let key = hex!("000102030405060708090a0b0c0d0e0f");
let iv = hex!("f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff");
let plaintext = b"Hello world!";
let cipher = Aes128Cbc::new_var(&key, &iv).unwrap();

// buffer must have enough space for message+padding
let mut buffer = [0u8; 32];
// copy message to the buffer
let pos = plaintext.len();
buffer[..pos].copy_from_slice(plaintext);
let ciphertext = cipher.encrypt(&mut buffer, pos).unwrap();

assert_eq!(ciphertext, hex!("1b7a4c403124ae2fb52bedc534d82fa8"));

// re-create cipher mode instance and decrypt the message
let cipher = Aes128Cbc::new_var(&key, &iv).unwrap();
let mut buf = ciphertext.to_vec();
let decrypted_ciphertext = cipher.decrypt(&mut buf).unwrap();

assert_eq!(decrypted_ciphertext, plaintext);

With an enabled std feature (which is enabled by default) you can use encrypt_vec and descrypt_vec methods:

let cipher = Aes128Cbc::new_var(&key, &iv).unwrap();
let ciphertext = cipher.encrypt_vec(plaintext);

assert_eq!(ciphertext, hex!("1b7a4c403124ae2fb52bedc534d82fa8"));

let cipher = Aes128Cbc::new_var(&key, &iv).unwrap();
let decrypted_ciphertext = cipher.decrypt_vec(&ciphertext).unwrap();

assert_eq!(decrypted_ciphertext, plaintext);

Note that this example does not use any authentification which can lead to serious vulnarabilities! For Message Authentication Code implementations take a look at RustCrypto/MACs repository.

License

All crates licensed under either of

• Apache License, Version 2.0
• MIT license

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.