basic_usage/
basic_usage.rs

1//! Basic usage example for Ever Crypto library
2//! 
3//! This example demonstrates:
4//! 1. XChaCha20Poly1305 encryption/decryption
5//! 2. Kyber1024 key encapsulation
6//! 3. Hybrid encryption combining both
7
8use ever_crypto::{
9    XChaChaCrypto, XChaChaKey, XChaChaNonce,
10    KyberCrypto,
11    Result,
12};
13
14fn main() -> Result<()> {
15    println!("=== Ever Crypto Library Example ===\n");
16    
17    // Example 1: XChaCha20Poly1305 Encryption
18    println!("1. XChaCha20Poly1305 Encryption");
19    xchacha_example()?;
20    
21    // Example 2: Kyber1024 Key Encapsulation
22    println!("\n2. Kyber1024 Key Encapsulation");
23    kyber_example()?;
24    
25    // Example 3: Hybrid Encryption
26    println!("\n3. Hybrid Encryption (Kyber1024 + XChaCha20Poly1305)");
27    hybrid_example()?;
28    
29    println!("\n=== All examples completed successfully! ===");
30    Ok(())
31}
32
33fn xchacha_example() -> Result<()> {
34    // Generate a key and nonce
35    let key = XChaChaKey::generate();
36    let nonce = XChaChaNonce::generate();
37    
38    // Message to encrypt
39    let plaintext = b"Hello, World! This is a secret message.";
40    let aad = b"Additional authenticated data";
41    
42    println!("  Original message: {:?}", std::str::from_utf8(plaintext).unwrap());
43    println!("  Key size: {} bytes", key.as_bytes().len());
44    println!("  Nonce size: {} bytes", nonce.as_bytes().len());
45    
46    // Encrypt the message
47    let ciphertext = XChaChaCrypto::encrypt(&key, &nonce, plaintext, Some(aad))?;
48    println!("  Ciphertext size: {} bytes", ciphertext.len());
49    
50    // Decrypt the message
51    let decrypted = XChaChaCrypto::decrypt(&key, &nonce, &ciphertext, Some(aad))?;
52    println!("  Decrypted message: {:?}", std::str::from_utf8(&decrypted).unwrap());
53    
54    // Verify they match
55    assert_eq!(plaintext, &decrypted[..]);
56    println!("  ✓ Encryption/Decryption successful!");
57    
58    Ok(())
59}
60
61fn kyber_example() -> Result<()> {
62    // Alice generates a key pair
63    let alice_keypair = KyberCrypto::generate_keypair();
64    
65    println!("  Alice's public key size: {} bytes", alice_keypair.public_key.as_bytes().len());
66    println!("  Alice's secret key size: {} bytes", alice_keypair.secret_key.as_bytes().len());
67    
68    // Bob encapsulates a shared secret for Alice
69    let (bob_shared_secret, ciphertext) = KyberCrypto::encapsulate(&alice_keypair.public_key);
70    
71    println!("  Encapsulated ciphertext size: {} bytes", ciphertext.as_bytes().len());
72    println!("  Bob's shared secret: {} bytes", bob_shared_secret.as_bytes().len());
73    
74    // Alice decapsulates the shared secret
75    let alice_shared_secret = KyberCrypto::decapsulate(&ciphertext, &alice_keypair.secret_key);
76    
77    println!("  Alice's shared secret: {} bytes", alice_shared_secret.as_bytes().len());
78    
79    // Verify they match
80    assert_eq!(bob_shared_secret.as_bytes(), alice_shared_secret.as_bytes());
81    println!("  ✓ Key encapsulation successful!");
82    
83    // Display key sizes
84    let sizes = KyberCrypto::sizes();
85    println!("  Component sizes:");
86    println!("    - Public key: {} bytes", sizes.public_key);
87    println!("    - Secret key: {} bytes", sizes.secret_key);
88    println!("    - Ciphertext: {} bytes", sizes.ciphertext);
89    println!("    - Shared secret: {} bytes", sizes.shared_secret);
90    
91    Ok(())
92}
93
94fn hybrid_example() -> Result<()> {
95    println!("  Setting up hybrid encryption...");
96    
97    // Step 1: Key establishment with Kyber1024
98    let alice_keypair = KyberCrypto::generate_keypair();
99    let (shared_secret, kyber_ciphertext) = KyberCrypto::encapsulate(&alice_keypair.public_key);
100    
101    // Step 2: Use shared secret as XChaCha20Poly1305 key
102    let xchacha_key = XChaChaKey::from_bytes(shared_secret.as_bytes())?;
103    
104    // Step 3: Encrypt data with XChaCha20Poly1305
105    let plaintext = b"This is a secret message using hybrid post-quantum encryption!";
106    println!("  Message to encrypt: {:?}", std::str::from_utf8(plaintext).unwrap());
107    
108    let (nonce, ciphertext) = XChaChaCrypto::encrypt_with_random_nonce(
109        &xchacha_key,
110        plaintext,
111        None,
112    )?;
113    
114    println!("  Hybrid encryption complete!");
115    println!("  - Kyber ciphertext size: {} bytes", kyber_ciphertext.as_bytes().len());
116    println!("  - XChaCha nonce size: {} bytes", nonce.as_bytes().len());
117    println!("  - XChaCha ciphertext size: {} bytes", ciphertext.len());
118    
119    // Decryption process:
120    println!("  Decrypting...");
121    
122    // Step 1: Alice decapsulates the shared secret
123    let alice_shared_secret = KyberCrypto::decapsulate(&kyber_ciphertext, &alice_keypair.secret_key);
124    let alice_xchacha_key = XChaChaKey::from_bytes(alice_shared_secret.as_bytes())?;
125    
126    // Step 2: Decrypt the message
127    let decrypted = XChaChaCrypto::decrypt(&alice_xchacha_key, &nonce, &ciphertext, None)?;
128    
129    println!("  Decrypted message: {:?}", std::str::from_utf8(&decrypted).unwrap());
130    
131    // Verify they match
132    assert_eq!(plaintext, &decrypted[..]);
133    println!("  ✓ Hybrid encryption/decryption successful!");
134    
135    Ok(())
136}
basic_usage/basic_usage.rs

basic_usage/
basic_usage.rs
