Node.js

RSA Sign with PKCS8 Encrypted Key

See more RSA Examples

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature (and then verify it). Node.js

NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

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

    var privKey = new chilkat.PrivateKey();

    // Load the private key from an RSA PEM file:
    success = privKey.LoadAnyFormatFile("raul_privateKey.key","a0123456789");
    if (success == false) {
        console.log(privKey.LastErrorText);
        return;
    }

    var rsa = new chilkat.Rsa();

    // Import the private key into the RSA component:
    success = rsa.UsePrivateKey(privKey);
    if (success == false) {
        console.log(rsa.LastErrorText);
        return;
    }

    // This example will sign a string, and receive the signature
    // in a hex-encoded string.  Therefore, set the encoding mode
    // to "hex":
    rsa.EncodingMode = "hex";

    var strData = "This is the string to be signed.";

    // Sign the string using the sha256 hash algorithm.
    // Other valid choices are sha1, sha384, sha512 and others.
    var hexSig = rsa.SignStringENC(strData,"sha256");
    if (rsa.LastMethodSuccess == false) {
        console.log(rsa.LastErrorText);
        return;
    }

    console.log(hexSig);

    // Now verify with the public key.
    // This example shows how to use the public key from 
    // a digital certificate (.cer file)
    var cert = new chilkat.Cert();
    success = cert.LoadFromFile("raul_publicKey.cer");
    if (success == false) {
        console.log(cert.LastErrorText);
        return;
    }

    var pubKey = new chilkat.PublicKey();
    cert.GetPublicKey(pubKey);

    var rsa2 = new chilkat.Rsa();
    success = rsa2.UsePublicKey(pubKey);
    if (success == false) {
        console.log(rsa2.LastErrorText);
        return;
    }

    // Verify the signature against the original data:
    rsa2.EncodingMode = "hex";
    success = rsa2.VerifyStringENC(strData,"sha256",hexSig);
    if (success == false) {
        console.log(rsa2.LastErrorText);
        return;
    }

    console.log("Signature verified!");

    // Verify with incorrect data:
    success = rsa2.VerifyStringENC("something else","sha256",hexSig);
    if (success !== true) {
        console.log("Signature not verified! (which was expected in this case)");
    }
    else {
        console.log("Hmmm... that's not right...");
    }


}

chilkatExample();