Rust

Get Ed25519 Key in Different Formats

See more Ed25519 Examples

Demonstrates how to get/save an Ed25519 private key to different formats.

Converting a private key from one format to another is done by loading in one format and saving/getting in another.

Note: This example requires Chilkat v9.5.0.83 or greater.

Rust

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

let eddsa = chilkat::EdDSA::new();
let prng = chilkat::Prng::new();
let priv_key = chilkat::PrivateKey::new();

// Generates a new ed25519 key and stores it in privKey.
if eddsa.gen_ed25519_key(&prng, &priv_key).is_err() {
    println!("{}", eddsa.last_error_text());
    return;
}

// ----------------------------------------------------------
// Ed25519 PKCS1 format
// 
// This is the format created by:  openssl genpkey -algorithm X25519 -out xkey.pem
let pkcs1_base64 = priv_key.get_pkcs1_enc("base64").unwrap_or_default();
println!("{}", pkcs1_base64);

// Sample output:  MC4CAQAwBQYDK2VuBCIEIB1mwirs+eC6XGbkjPIiZyBwQ7768uSd9v5PHOLFbIXo

// PKCS1 is a binary ASN.1 DER format.  You can examine the contents with two online tools:
// 1) Go to ASN.1 Decoder  and paste the base64 into the online form.
// 2) Or Decode Base64 ASN.1 to XML 

// The PKCS1 ASN.1 format for an Ed25519 key look like this:
//   SEQUENCE
//     INTEGER 0
//     SEQUENCE
//       OBJECT IDENTIFIER 1.3.101.110 curveX25519 (ECDH 25519 key agreement algorithm)
//     OCTET STRING 
//       OCTET STRING (32 byte) 1D66C...

// Save it directly to a file.
let _ = priv_key.save_pkcs1_file("qa_output/ed25519.key").is_ok();

// ----------------------------------------------------------
// Ed25519 Unencrypted PKCS8 format
// 
// For ed25519, the ASN.1 output is the same as for PKCS1.
let pkcs8_base64 = priv_key.get_pkcs8_enc("base64").unwrap_or_default();
println!("{}", pkcs8_base64);

// PKCS8 is a binary ASN.1 DER format.  You can examine the contents with two online tools:
// 1) Go to ASN.1 Decoder  and paste the base64 into the online form.
// 2) Or Decode Base64 ASN.1 to XML 

// ----------------------------------------------------------
// Ed25519 Encrypted PKCS8 format
// 
// Note: The encrypted output cannot be examined using the above online tools because the ASN.1 is encrypted.
let password = "secret".to_string();
let pkcs8_enc_base64 = priv_key.get_pkcs8_encrypted_enc("base64", &password).unwrap_or_default();
println!("{}", pkcs8_enc_base64);

// ----------------------------------------------------------
// Ed25519 in PEM format:
// 
let ed25519_pem = priv_key.get_pkcs1_pem().unwrap_or_default();
println!("{}", ed25519_pem);

// Sample output:

// -----BEGIN PRIVATE KEY-----
// MC4CAQAwBQYDK2VuBCIEIOKPhbULJagBAi7hbRdn1f4AAzh1RqqCHqCAvau7N6yO
// -----END PRIVATE KEY-----

// ----------------------------------------------------------
// Ed25519 in JWK Format
// 
let jwk = priv_key.get_jwk().unwrap_or_default();

let json = chilkat::JsonObject::new();
let _ = json.load(&jwk);
json.set_emit_compact(false);
println!("{}", json.emit().unwrap_or_default());

// Sample output:
// {
//   "kty": "OKP",
//   "crv": "Ed25519",
//   "x": "SE2Kne5xt51z1eciMH2T2ftDQp96Gl6FhY6zSQujiP0",
//   "d": "O-eRXewadF0sNyB0U9omcnt8Qg2ZmeK3WSXPYgqe570",
//   "use": "sig"
// }

// In the above JWK, x is the public key, y is the private key.
// Both are 32 bytes and are base64-url encoded.

// ----------------------------------------------------------
// Ed25519 in XML Format
// 
let ed25519_xml = priv_key.get_xml().unwrap_or_default();
println!("{}", ed25519_xml);

// Sample output:  <Ed25519KeyValue>w4b/gI0zgYKgjtfWLjNfc4issmP7Qap84uesYNgEefP/WoY3jNOhOzgTYsMtOnuyGn3MdA4NZtsUXVNI1NiTlA==</Ed25519KeyValue>

// The base64 content is composed of the concatenation of the 32-byte private key with the 32-byte public key and then base64 encoded.
// In other words:  Base64(privKey || pubKey)

// ----------------------------------------------------------
// Ed25519 in Raw Hex Format
// 
let sb_pub_key_hex = chilkat::StringBuilder::new();
let priv_key_hex = priv_key.get_raw_hex(&sb_pub_key_hex).unwrap_or_default();

// We should have a 32-byte private key (a 64 character hex string).
println!("private key = {}", priv_key_hex);

// We should have a 32-byte public key (a 64 character hex string).
println!("public key = {}", sb_pub_key_hex.get_as_string().unwrap_or_default());

// Sample output:
// key type = ed25519
// size in bits = 256
// private key = d4ee72dbf913584ad5b6d8f1f769f8ad3afe7c28cbf1d4fbe097a88f44755842
// public key = 19bf44096984cdfe8541bac167dc3b96c85086aa30b6b6cb0c5c38ad703166e1