Rust

JWE using PBES2 Key Wrapping

See more JSON Web Encryption (JWE) Examples

Demonstrates how to create and decrypt a JWE that using PBES2 key wrapping.

This example demonstrates PBES2 with HMAC SHA-256 and A128KW wrapping. It is also possible to do the following by simply changing the "alg" parameter:

• PBES2 with HMAC SHA-384 and A192KW wrapping
• PBES2 with HMAC SHA-512 and A256KW wrapping

Note: This example requires Chilkat v9.5.0.66 or greater.

Rust

// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// Note: This example requires Chilkat v9.5.0.66 or greater.

let plaintext = "Live long and prosper.".to_string();

let jwe = chilkat::Jwe::new();

// First build the JWE Protected Header..
let jwe_prot_hdr = chilkat::JsonObject::new();
let _ = jwe_prot_hdr.append_string("alg", "PBES2-HS256+A128KW");
let _ = jwe_prot_hdr.append_string("enc", "A128GCM");

// PBES2 requires two additional parameters:
// 1) A random salt parameter ("p2s") containing 8 or more bytes in base64url format.
// 2) An iteration count parameter ("p2c").  A minimum count of 1000 is recommended.
//    The iteration count is intended to make the PBES2 computation more expensive (time consuming)
//    to prevent brute-force attacks.
let prng = chilkat::Prng::new();
let _ = jwe_prot_hdr.append_string("p2s", &prng.gen_random(16, "base64url").unwrap_or_default());
let _ = jwe_prot_hdr.append_string("p2c", "1000");

println!("JWE Protected Header: {}", jwe_prot_hdr.emit().unwrap_or_default());
println!("--");

// Don't forget to actually provide the protected header to the JWE object:
let _ = jwe.set_protected_header(&jwe_prot_hdr);

// Set the PBES2 password
let recipient_index = 0;
let _ = jwe.set_password(recipient_index, "top secret");

// Encrypt and return the JWE:
let Ok(str_jwe) = jwe.encrypt(&plaintext, "utf-8") else {
    println!("{}", jwe.last_error_text());
    return;
};

// Show the JWE we just created:
println!("{}", str_jwe);

// Decrypt the JWE.
let jwe2 = chilkat::Jwe::new();
if jwe2.load_jwe(&str_jwe).is_err() {
    println!("{}", jwe2.last_error_text());
    return;
}

// Set the PBES2 password
let _ = jwe2.set_password(recipient_index, "top secret");

// Decrypt.
let Ok(original_plaintext) = jwe2.decrypt(0, "utf-8") else {
    println!("{}", jwe2.last_error_text());
    return;
};

println!("original text: ");
println!("{}", original_plaintext);

// Sample output:

// JWE Protected Header: {"alg":"PBES2-HS256+A128KW","enc":"A128GCM","p2s":"z39rTEfRy1T1Yn_D1mZRlg","p2c":"1000"}
// --
// eyJhbGciOiJQQkVTMi1IUzI1NitBMTI4S1ciLCJlbmMiOiJBMTI4R0NNIiwicDJzIjoiejM5clRFZlJ5MVQxWW5fRDFtWlJsZyIsInAyYyI6IjEwMDAifQ.koYt6PrFmYwcwdcT7ZcvXHA1d-Xez5h4.luGlbvEnZp-7IsBOj42Yhw.YMTcfLf8Qe4zazozGV2OAu3cUdQ8Kg.rWub47ESWkc6IqZJTvSTmg
// original text: 
// Live long and prosper.