Rust Requires Chilkat v11.0.0+

JWS Using HMAC SHA-256

See more JSON Web Signatures (JWS) Examples

Creates a JSON Web Signatures (JWS) using HMAC SHA-256. Rust

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

// First create the JWS Protected Header
let jws_prot_hdr = chilkat::JsonObject::new();
let _ = jws_prot_hdr.append_string("typ", "JWT");
let _ = jws_prot_hdr.append_string("alg", "HS256");
println!("JWS Protected Header: {}", jws_prot_hdr.emit().unwrap_or_default());

// Output:
// JWS Protected Header: {"typ":"JWT","alg":"HS256"}

let jws = chilkat::Jws::new();

// Set the HMAC key:
let hmac_key = "AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow".to_string();
let mut signature_index = 0;
let _ = jws.set_mac_key(signature_index, &hmac_key, "base64url");

// Set the protected header:
let _ = jws.set_protected_header(signature_index, &jws_prot_hdr);

// Set the payload.
let b_include_bom = false;
let payload_str = "In our village, folks say God crumbles up the old moon into stars.".to_string();
let _ = jws.set_payload(&payload_str, "utf-8", b_include_bom);

// Create the JWS
// By default, the compact serialization is used.
let Ok(jws_compact) = jws.create_jws() else {
    println!("{}", jws.last_error_text());
    return;
};

println!("JWS: {}", jws_compact);

// sample output:
// JWS: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.bsYsi8HJ0N6OqGI1hKQ9QQRNPxxA5qMpcHLtOvXatk8

// Now load the JWS, validate, and recover the original text.
let jws2 = chilkat::Jws::new();

// Load the JWS.
let _ = jws2.load_jws(&jws_compact).is_ok();

// Set the MAC key used for validation.
signature_index = 0;
let _ = jws2.set_mac_key(signature_index, &hmac_key, "base64url");

// Validate the 1st (and only) signature at index 0..
let v = jws2.validate(signature_index);
if v < 0 {
    // Perhaps Chilkat was not unlocked or the trial expired..
    println!("Method call failed for some other reason.");
    println!("{}", jws2.last_error_text());
    return;
}

if v == 0 {
    println!("Invalid signature.  The MAC key was incorrect, the JWS was invalid, or both.");
    return;
}

// If we get here, the signature was validated..
println!("Signature validated.");

// Recover the original content:
println!("{}", jws2.get_payload("utf-8").unwrap_or_default());

// Examine the protected header:

let jose_header = chilkat::JsonObject::new();
if jws2.get_protected_h(signature_index, &jose_header).is_err() {
    println!("{}", jws2.last_error_text());
    return;
}

jose_header.set_emit_compact(false);

println!("Protected (JOSE) header:");
println!("{}", jose_header.emit().unwrap_or_default());

// Output:

// 	Signature validated.
// 	In our village, folks say God crumbles up the old moon into stars.
// 	Protected (JOSE) header:
// 	{ 
// 	  "typ": "JWT",
// 	  "alg": "HS256"
// 	}