14 releases
0.7.4 | May 2, 2023 |
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0.7.3 | Feb 6, 2023 |
0.7.2 | Apr 21, 2022 |
0.7.1 | Mar 25, 2022 |
0.5.0 | Dec 23, 2021 |
#983 in Cryptography
25KB
496 lines
XXXDH
Implementation of the Extended Triple Diffie-Hellman key exchange protocol written in Rust.
Implementation is close to the Signal Spec, but Ristretto point Curve25519 used as a curve for the default implementation. Though underlying algorithms could be changed fairly easily.
Usage
//! Basic example.
use cryptimitives::{aead, kdf::sha256, key::x25519_ristretto};
use cryptraits::{convert::ToVec, key::KeyPair, signature::Sign};
use rand_core::OsRng;
use xxxdh::{
inmem, IdentityKeyStorage, OnetimeKeyStorage, PreKeyStorage, Protocol, SignatureStorage,
};
fn main() {
// Instantiate Alice protocol.
let alice_identity = x25519_ristretto::KeyPair::generate_with(OsRng);
let alice_prekey = x25519_ristretto::KeyPair::generate_with(OsRng);
let alice_signature = alice_identity.sign(&alice_prekey.to_public().to_vec());
let mut alice_protocol = Protocol::<
x25519_ristretto::SecretKey,
x25519_ristretto::EphemeralSecretKey,
x25519_ristretto::Signature,
inmem::Storage<_, _>,
sha256::Kdf,
aead::aes_gcm::Aes256Gcm,
>::new(alice_identity, alice_prekey, alice_signature, None);
// Instantiate Bob protocol.
let onetime_keypair = x25519_ristretto::KeyPair::generate_with(OsRng);
let bob_identity = x25519_ristretto::KeyPair::generate_with(OsRng);
let bob_prekey = x25519_ristretto::KeyPair::generate_with(OsRng);
let bob_signature = bob_identity.sign(&bob_prekey.to_public().to_vec());
let mut bob_protocol = Protocol::<
x25519_ristretto::SecretKey,
x25519_ristretto::EphemeralSecretKey,
x25519_ristretto::Signature,
inmem::Storage<_, _>,
sha256::Kdf,
aead::aes_gcm::Aes256Gcm,
>::new(
bob_identity,
bob_prekey,
bob_signature,
Some(vec![onetime_keypair]),
);
// Derive shared secret for Alice and prepare message for Bob.
let bob_identity = bob_protocol.storage.get_identity_key_pair().to_public();
let bob_prekey = bob_protocol.storage.get_prekey_pair().to_public();
let bob_signature = bob_protocol
.storage
.get_signature(&bob_prekey)
.unwrap()
.unwrap();
let onetime_key = bob_protocol.storage.provide_ontime_key().unwrap().unwrap();
let (alice_identity, alice_ephemeral_key, bob_onetime_key, alice_sk, nonce, ciphertext) =
alice_protocol
.prepare_init_msg(&bob_identity, &bob_prekey, bob_signature, onetime_key)
.unwrap();
// Derive shared secret for Bob using Alice credentials.
let bob_sk = bob_protocol
.derive_shared_secret(
&alice_identity,
&alice_ephemeral_key,
&bob_onetime_key,
&nonce,
&ciphertext,
)
.unwrap();
println!("Alice shared secret: {:?}", alice_sk);
println!("Bob shared secret: {:?}", bob_sk);
}
Dependencies
~7MB
~148K SLoC