full_exchange/
full_exchange.rs

1use pq_msg::{
2    exchange::pair::KEMPair, messaging::MessageSession, messaging::create_nonce,
3    messaging::gen_session_id, signatures::keypair::SignerPair,
4};
5
6fn main() {
7    let alice_kem = KEMPair::create();
8    let alice_signer = SignerPair::create();
9
10    let bob_kem = KEMPair::create();
11    let bob_signer = SignerPair::create();
12
13    // Create a base nonce with a new session id, and a counter of
14    let base_nonce = create_nonce(&gen_session_id(), 0);
15
16    // Lets create the message session for Alice first
17    let (mut alice_session, ciphertext) = MessageSession::new_initiator(
18        alice_kem,
19        alice_signer.clone(),
20        base_nonce,
21        &bob_kem.to_bytes().unwrap().0,    // Bob's public KEM key
22        &bob_signer.to_bytes().unwrap().0, // Bob's public signer key
23    )
24    .unwrap();
25
26    // Now for Bob it would look like this
27    let mut bob_session = MessageSession::new_responder(
28        bob_kem,
29        bob_signer.clone(),
30        base_nonce,
31        &ciphertext,
32        &alice_signer.to_bytes().unwrap().0, // Alice's public signer key
33    )
34    .unwrap();
35
36    // Now both sessions contain a shared secret they use to encrypt and decrypt messages
37    // and a nonce that is incremented with each message sent or received.
38
39    // Alice creates a mesasge and prepares to send it to Bob
40    let message = b"Hello, Bob! This is a secret message.";
41    let encrypted_message = alice_session.craft_message(message).unwrap();
42
43    // Bob decrypts and verifies Alice's message
44    let raw_message = bob_session.validate_message(&encrypted_message).unwrap();
45
46    // Both message and raw_message are equal, let's print them out to illustrate
47    let message_str = String::from_utf8_lossy(message);
48    let raw_message_str = String::from_utf8_lossy(&raw_message);
49
50    println!("[1] Alice's message: {}", message_str);
51    println!("[2] Bob's decrypted message: {}", raw_message_str);
52
53    // Bob crafts a reply message to Alice
54    let reply = b"Hello, Alice! I received your message safely.";
55    let encrypted_reply = bob_session.craft_message(reply).unwrap();
56
57    // Alice decrypts and verifies Bob's reply
58    let raw_reply = alice_session.validate_message(&encrypted_reply).unwrap();
59
60    // Both reply and raw_reply are equal, let's print them again
61    let reply_str = String::from_utf8_lossy(reply);
62    let raw_reply_str = String::from_utf8_lossy(&raw_reply);
63
64    println!("[3] Bob's reply: {}", reply_str);
65    println!("[4] Alice's decrypted reply: {}", raw_reply_str);
66}
full_exchange/full_exchange.rs

full_exchange/
full_exchange.rs
