JavaScript Requires Chilkat v11.0.0+

RSA SHA256 Signature using Private Key from Java Keystore

See more RSA Examples

Signs plaintext using RSA SHA256 using a key from a Java keystore.

Duplicatest this code:

KeyStore keystore; // key repository for keys containing signature certificate
String alias; // alias for the certificate in the key repository
String password; // password for the certificate's private key
String plaintext; // text being signed


Signature signature = Signature.getInstance("SHA256withRSA");
signature.initSign((PrivateKey) keystore.getKey(alias, password.toCharArray()));
signature.update(plaintext.getBytes("UTF-8"));
byte[] rsa_text= signature.sign();

JavaScript

var success = false;

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

var jks = new CkJavaKeyStore();

var jksPassword = "secret";

//  Load the Java keystore from a file.  The JKS file password is used
//  to verify the keyed digest that is found at the very end of the keystore.
//  It verifies that the keystore has not been modified.
success = jks.LoadFile(jksPassword,"qa_data/jks/sample_secret.jks");
if (success == false) {
    console.log(jks.LastErrorText);
    return;
}

//  Get the private key from the JKS.
//  The private key password may be different than the file password.
var privKeyPassword = "secret";
var caseSensitive = false;
var privKey = new CkPrivateKey();
success = jks.PrivateKeyOf(privKeyPassword,"some.alias",caseSensitive,privKey);
if (success == false) {
    console.log(jks.LastErrorText);
    return;
}

//  Establish the RSA object and tell it to use the private key..
var rsa = new CkRsa();

success = rsa.UsePrivateKey(privKey);
if (success == false) {
    console.log(rsa.LastErrorText);
    return;
}

//  Indicate we'll be signing the utf-8 byte representation of the string..
rsa.Charset = "utf-8";

//  Sign some plaintext using RSA-SHA256

var plaintext = "this is the text to be signed";
binarySignature = rsa.SignString(plaintext,"SHA256");
if (rsa.LastMethodSuccess == false) {
    console.log(rsa.LastErrorText);
    return;
}

//  Alternatively, if the signature is desired in some encoded string form,
//  such as base64, base64-url, hex, etc.
rsa.EncodingMode = "base64-url";
var signatureStr = rsa.SignStringENC(plaintext,"SHA256");
console.log("base64-url RSA signature: " + signatureStr);