Rust Requires Chilkat v11.0.0+

JWE using RSAES-OAEP and AES GCM

See more JSON Web Encryption (JWE) Examples

This example duplicates the example A.1 in RFC 7516 for JSON Web Encryption (JWE). 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 = "The true sign of intelligence is not knowledge but imagination.".to_string();

// ---------------------------------
// A.1.1 JOSE Header
// First build the JWE Protected Header.
// We want to build this: {"alg":"RSA-OAEP","enc":"A256GCM"}
let jwe_prot_hdr = chilkat::JsonObject::new();
let _ = jwe_prot_hdr.append_string("alg", "RSA-OAEP");
let _ = jwe_prot_hdr.append_string("enc", "A256GCM");
println!("JWE Protected Header: {}", jwe_prot_hdr.emit().unwrap_or_default());
println!("--");

// ---------------------------------
// A.1.2 Content Encryption Key
// Note: Chilkat automatically generates the random CEK internally.
// The application does not need to explicitly take this step.

// ---------------------------------
// A.1.3.  Key Encryption
// The application should load an RSA private key from any format.
// However, the application does not need to explicitly construct the JWE Encrypted Key.
// Chilkat automatically does it internally.
// The design of the Chilkat JWE API is to allow the application to create the JWE
// after specifying the inputs.  (This is in contrast to forcing the application developer
// to painstakingly go through each step of the JWE construction process.)

// The specific RSA key used in the A.1 example is the following JWK:
let sb_jwk = chilkat::StringBuilder::new();
let _ = sb_jwk.append("{\"kty\": \"RSA\",");
let _ = sb_jwk.append("\"n\": \"oahUIoWw0K0usKNuOR6H4wkf4oBUXHTxRvgb48E-BVvxkeDNjbC4he8rUW");
let _ = sb_jwk.append("cJoZmds2h7M70imEVhRU5djINXtqllXI4DFqcI1DgjT9LewND8MW2Krf3S");
let _ = sb_jwk.append("psk_ZkoFnilakGygTwpZ3uesH-PFABNIUYpOiN15dsQRkgr0vEhxN92i2a");
let _ = sb_jwk.append("sbOenSZeyaxziK72UwxrrKoExv6kc5twXTq4h-QChLOln0_mtUZwfsRaMS");
let _ = sb_jwk.append("tPs6mS6XrgxnxbWhojf663tuEQueGC-FCMfra36C9knDFGzKsNa7LZK2dj");
let _ = sb_jwk.append("YgyD3JR_MB_4NUJW_TqOQtwHYbxevoJArm-L5StowjzGy-_bq6Gw\",");
let _ = sb_jwk.append("\"e\": \"AQAB\",");
let _ = sb_jwk.append("\"d\": \"kLdtIj6GbDks_ApCSTYQtelcNttlKiOyPzMrXHeI-yk1F7-kpDxY4-WY5N");
let _ = sb_jwk.append("WV5KntaEeXS1j82E375xxhWMHXyvjYecPT9fpwR_M9gV8n9Hrh2anTpTD9");
let _ = sb_jwk.append("3Dt62ypW3yDsJzBnTnrYu1iwWRgBKrEYY46qAZIrA2xAwnm2X7uGR1hghk");
let _ = sb_jwk.append("qDp0Vqj3kbSCz1XyfCs6_LehBwtxHIyh8Ripy40p24moOAbgxVw3rxT_vl");
let _ = sb_jwk.append("t3UVe4WO3JkJOzlpUf-KTVI2Ptgm-dARxTEtE-id-4OJr0h-K-VFs3VSnd");
let _ = sb_jwk.append("VTIznSxfyrj8ILL6MG_Uv8YAu7VILSB3lOW085-4qE3DzgrTjgyQ\",");
let _ = sb_jwk.append("\"p\": \"1r52Xk46c-LsfB5P442p7atdPUrxQSy4mti_tZI3Mgf2EuFVbUoDBvaRQ-");
let _ = sb_jwk.append("SWxkbkmoEzL7JXroSBjSrK3YIQgYdMgyAEPTPjXv_hI2_1eTSPVZfzL0lf");
let _ = sb_jwk.append("fNn03IXqWF5MDFuoUYE0hzb2vhrlN_rKrbfDIwUbTrjjgieRbwC6Cl0\",");
let _ = sb_jwk.append("\"q\": \"wLb35x7hmQWZsWJmB_vle87ihgZ19S8lBEROLIsZG4ayZVe9Hi9gDVCOBm");
let _ = sb_jwk.append("UDdaDYVTSNx_8Fyw1YYa9XGrGnDew00J28cRUoeBB_jKI1oma0Orv1T9aX");
let _ = sb_jwk.append("IWxKwd4gvxFImOWr3QRL9KEBRzk2RatUBnmDZJTIAfwTs0g68UZHvtc\",");
let _ = sb_jwk.append("\"dp\": \"ZK-YwE7diUh0qR1tR7w8WHtolDx3MZ_OTowiFvgfeQ3SiresXjm9gZ5KL");
let _ = sb_jwk.append("hMXvo-uz-KUJWDxS5pFQ_M0evdo1dKiRTjVw_x4NyqyXPM5nULPkcpU827");
let _ = sb_jwk.append("rnpZzAJKpdhWAgqrXGKAECQH0Xt4taznjnd_zVpAmZZq60WPMBMfKcuE\",");
let _ = sb_jwk.append("\"dq\": \"Dq0gfgJ1DdFGXiLvQEZnuKEN0UUmsJBxkjydc3j4ZYdBiMRAy86x0vHCj");
let _ = sb_jwk.append("ywcMlYYg4yoC4YZa9hNVcsjqA3FeiL19rk8g6Qn29Tt0cj8qqyFpz9vNDB");
let _ = sb_jwk.append("UfCAiJVeESOjJDZPYHdHY8v1b-o-Z2X5tvLx-TCekf7oxyeKDUqKWjis\",");
let _ = sb_jwk.append("\"qi\": \"VIMpMYbPf47dT1w_zDUXfPimsSegnMOA1zTaX7aGk_8urY6R8-ZW1FxU7");
let _ = sb_jwk.append("AlWAyLWybqq6t16VFd7hQd0y6flUK4SlOydB61gwanOsXGOAOv82cHq0E3");
let _ = sb_jwk.append("eL4HrtZkUuKvnPrMnsUUFlfUdybVzxyjz9JF_XyaY14ardLSjf4L_FNY\"}");

// Load this JWK into a Chilkat private key object.
let rsa_priv_key = chilkat::PrivateKey::new();
if rsa_priv_key.load_jwk(&sb_jwk.get_as_string().unwrap_or_default()).is_err() {
    println!("{}", rsa_priv_key.last_error_text());
    return;
}

// The public key is used to encrypt (i.e. create the JWE), 
// and the private key is used to decrypt.
// The RSA public key is simply a subset of the private key.  The RSA public key
// is composed of the "n" and "e" members shown above.  These are also known as the
// modulus and exponent.
// We can simply get the public key object from the private key object
let rsa_pub_key = chilkat::PublicKey::new();
let _ = rsa_priv_key.to_public_key(&rsa_pub_key);

// ---------------------------------
// A.1.4.  Initialization Vector
// Chilkat automatically generates the necessary random IV internally.  
// The application does not need to do this explicitly.

// ---------------------------------
// A.1.5.  Additional Authenticated Data
// The Additional Authenticated Data encryption parameter is
// ASCII(BASE64URL(UTF8(JWE Protected Header))).
// Again, Chilkat automatically takes care of this internally.
// The application does not need to explicitly take this step.

// ---------------------------------
// A.1.6.  Content Encryption
// Again... this step is handled by Chilkat internally.

// ---------------------------------
// A.1.7.  Complete Representation
// The application need only call the Encrypt, EncryptSb, or EncryptBd method
// return the fully assembled JWE.  
// The final representation in the Compact Serialization 
// is the string BASE64URL(UTF8(JWE Protected Header)) || '.' ||
// BASE64URL(JWE Encrypted Key) || '.' || BASE64URL(JWE Initialization
// Vector) || '.' || BASE64URL(JWE Ciphertext) || '.' || BASE64URL(JWE
// Authentication Tag).

let jwe = chilkat::Jwe::new();
let _ = jwe.set_protected_header(&jwe_prot_hdr);
let _ = jwe.set_public_key(0, &rsa_pub_key);

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

// Note: The RSA OAEP algorithm uses random padding bytes internally.
// Therefore, the results will appear different each time -- even if the
// identical plaintext is encrypted with the identical RSA key. 
// (Do not expect the appearance of the results to be the same as what
// is published in the RFC.  However, what is published in the RFC *should*
// be decryptable using the code that follows.)
println!("{}", str_jwe);

// Let's decrypt the JWE that was just produced.
// Do the following to decrypt a JWE:
// 1) Load the JWE.
// 2) Set the private key for decryption.
// 3) Decrypt.
let jwe2 = chilkat::Jwe::new();
if jwe2.load_jwe(&str_jwe).is_err() {
    println!("{}", jwe2.last_error_text());
    return;
}

// Provide the RSA private key for decryption.
// (The JWE was encrypted for a single recipient at index 0.)
let _ = jwe2.set_private_key(0, &rsa_priv_key);

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

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

// ---------------------------------------------------------------------------------
// It should also be possible to decrypt the JWE as shown in RFC 7516, Appendix A.1.7
// because it was produced using the same RSA key.

let sb_jwe = chilkat::StringBuilder::new();
let _ = sb_jwe.append("eyJhbGciOiJSU0EtT0FFUCIsImVuYyI6IkEyNTZHQ00ifQ.");
let _ = sb_jwe.append("OKOawDo13gRp2ojaHV7LFpZcgV7T6DVZKTyKOMTYUmKoTCVJRgckCL9kiMT03JGe");
let _ = sb_jwe.append("ipsEdY3mx_etLbbWSrFr05kLzcSr4qKAq7YN7e9jwQRb23nfa6c9d-StnImGyFDb");
let _ = sb_jwe.append("Sv04uVuxIp5Zms1gNxKKK2Da14B8S4rzVRltdYwam_lDp5XnZAYpQdb76FdIKLaV");
let _ = sb_jwe.append("mqgfwX7XWRxv2322i-vDxRfqNzo_tETKzpVLzfiwQyeyPGLBIO56YJ7eObdv0je8");
let _ = sb_jwe.append("1860ppamavo35UgoRdbYaBcoh9QcfylQr66oc6vFWXRcZ_ZT2LawVCWTIy3brGPi");
let _ = sb_jwe.append("6UklfCpIMfIjf7iGdXKHzg.");
let _ = sb_jwe.append("48V1_ALb6US04U3b.");
let _ = sb_jwe.append("5eym8TW_c8SuK0ltJ3rpYIzOeDQz7TALvtu6UG9oMo4vpzs9tX_EFShS8iB7j6ji");
let _ = sb_jwe.append("SdiwkIr3ajwQzaBtQD_A.");
let _ = sb_jwe.append("XFBoMYUZodetZdvTiFvSkQ");

if jwe2.load_jwe_sb(&sb_jwe).is_err() {
    println!("{}", jwe2.last_error_text());
    return;
}

// Provide the RSA private key for decryption.
let _ = jwe2.set_private_key(0, &rsa_priv_key);

// Decrypt.
original_plaintext = jwe2.decrypt(0, "utf-8").unwrap_or_default();
if !jwe2.last_method_success() {
    println!("{}", jwe2.last_error_text());
    return;
}

println!("{}", original_plaintext);