gimli-crypto

A no_std compatible Rust implementation of the Gimli cryptographic permutation and its applications:

• AEAD (aead/gimli24v1): Authenticated Encryption with Associated Data
• Hash (hash/gimli24v1): Cryptographic hash function

Based on the Gimli specification by Bernstein et al.

Usage

AEAD Encryption (In-Place)

use gimli_crypto::{encrypt_in_place, decrypt_in_place, KEY_SIZE, NONCE_SIZE};

let key = [0u8; KEY_SIZE];
let nonce = [1u8; NONCE_SIZE]; // MUST be unique per encryption!
let mut data = *b"Secret message!!";
let aad = b"public header";

// Encrypt in-place
let tag = encrypt_in_place(&key, &nonce, aad, &mut data);

// Decrypt in-place with authentication
decrypt_in_place(&key, &nonce, aad, &mut data, &tag)
    .expect("authentication failed");

assert_eq!(&data, b"Secret message!!");

AEAD Encryption (RustCrypto Trait)

use gimli_crypto::GimliAead;
use aead::{AeadInPlace, KeyInit};
use aead::generic_array::GenericArray;

let key = GenericArray::from([1u8; 32]);
let cipher = GimliAead::new(&key);

let nonce = GenericArray::from([2u8; 16]);
let plaintext = *b"Hello, RustCrypto AEAD!";
let aad = b"associated data";

let mut ciphertext = plaintext.clone();
let tag = cipher
    .encrypt_in_place_detached(&nonce, aad, &mut ciphertext)
    .expect("encryption failed");

cipher
    .decrypt_in_place_detached(&nonce, aad, &mut ciphertext, &tag)
    .expect("decryption failed");

assert_eq!(&ciphertext, b"Hello, RustCrypto AEAD!");

Cryptographic Hash

use gimli_crypto::{hash, Hasher};

// One-shot hashing
let digest = hash(b"Hello, Gimli!");
assert_eq!(digest.len(), 32); // 256-bit output

// Incremental hashing
let mut hasher = Hasher::new();
hasher.update(b"Hello, ");
hasher.update(b"Gimli!");
let digest2 = hasher.finalize();

assert_eq!(digest, digest2);

Hash (RustCrypto Digest Trait)

use gimli_crypto::GimliHash;
use digest::Digest;

let mut hasher = GimliHash::new();
hasher.update(b"Hello, ");
hasher.update(b"Gimli!");
let result = hasher.finalize();

References

• Gimli specification paper
• Gimli website

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

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.