The AEGIS Family of Authenticated Encryption Algorithms

This is a performant and feature complete pure-rust implementation of AEGIS.

While https://github.com/jedisct1/rust-aegis/ exists, it only offers good performance using the C implementation. Its pure-rust implementation only offers Aegis256 and Aegis128l with ok perforamnce.

Currently this is built using an unstable version of RustCrypto traits.

Features

Authenticated Encryption with Additional Data (AEAD)

• Aegis128L offers authenticated encryption with 128 bit keys and nonces.
• Aegis256 offers authenticated encryption with 256 bit keys and nonces.

Both support either 128 bit or 256 bit message tags.

Aside from the core algorithms, there is also

• Aegis128X2 - Like Aegis128L but operates on 2 blocks at a time, offering performance improvements with AVX2.
• Aegis256X2 - Like Aegis256 but operates on 2 blocks at a time, offering performance improvements with AVX2.
• Aegis128X4 - Like Aegis128L but operates on 4 blocks at a time, offering performance improvements with AVX512.
• Aegis256X4 - Like Aegis256 but operates on 4 blocks at a time, offering performance improvements with AVX512.

Message Authentication Codes (MAC)

• AegisMac128: offers message authentication with 128 bit keys and nonces.
• AegisMac256 offers message authentication with 256 bit keys and nonces.

Both support either 128 bit or 256 bit authentication codes.

Aside from the core algorithms, there is also

• AegisMac128X2 - Like AegisMac128L but operates on 2 blocks at a time, offering performance improvements with AVX2.
• AegisMac256X2 - Like AegisMac256 but operates on 2 blocks at a time, offering performance improvements with AVX2.
• AegisMac128X4 - Like AegisMac128L but operates on 4 blocks at a time, offering performance improvements with AVX512.
• AegisMac256X4 - Like AegisMac256 but operates on 4 blocks at a time, offering performance improvements with AVX512.

## Usage

AEAD

use aegis_cl::{
    aead::{Aead, AeadCore, KeyInit},
    Aegis128L, Tag128
};

let key = Aegis128L::<Tag128>::generate_key().unwrap();
let cipher = Aegis128L::<Tag128>::new(&key);
let nonce = Aegis128L::<Tag128>::generate_nonce().unwrap();
let ciphertext = cipher.encrypt(&nonce, b"plaintext message".as_ref()).unwrap();
let plaintext = cipher.decrypt(&nonce, ciphertext.as_ref()).unwrap();
assert_eq!(&plaintext, b"plaintext message");

MAC

use aegis_cl::{
    digest::{Mac},
    digest::crypto_common::{KeyIvInit},
    AegisMac128L, Tag128
};

let key = AegisMac128L::<Tag128>::generate_key().unwrap();
let iv = AegisMac128L::<Tag128>::generate_iv().unwrap();

let mut mac = AegisMac128L::<Tag128>::new(&key, &iv);
mac.update(b"plaintext message".as_ref());
let tag = mac.finalize().into_bytes();

let mut mac = AegisMac128L::<Tag128>::new(&key, &iv);
mac.update(b"plaintext message".as_ref());
mac.verify(&tag).unwrap();

Stream

use aegis_cl::{
    cipher::{KeyIvInit, StreamCipher},
    high::AegisStream, mid::State128X, X1,
};

let key = AegisStream::<State128X<X1>>::generate_key().unwrap();
let iv = AegisStream::<State128X<X1>>::generate_iv().unwrap();

let mut buffer = *b"plaintext message";

let mut cipher = AegisStream::<State128X<X1>>::new(&key, &iv);
cipher.apply_keystream(&mut buffer);

let mut cipher = AegisStream::<State128X<X1>>::new(&key, &iv);
cipher.apply_keystream(&mut buffer);

assert_eq!(&buffer, b"plaintext message");