Node.js

Generate RSA Key and Sign a String

See more RSA Examples

Demonstrates how to generate a new RSA public/private key pair and use it to generate a signature for a string. The (binary) digital signature is returned as a hexidecimalized string. 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 rsa = new chilkat.Rsa();

    // Generate a 2048-bit RSA key.
    var privKey = new chilkat.PrivateKey();
    success = rsa.GenKey(2048,privKey);

    rsa.UsePrivateKey(privKey);

    // Return the signature in hex.
    rsa.EncodingMode = "hex";

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

    // Sign the SHA256 hash of the string.
    var hexSig = rsa.SignStringENC(strData,"sha256");

    console.log(hexSig);

    // Now verify the signature:
    var pubKey = new chilkat.PublicKey();
    privKey.ToPublicKey(pubKey);
    rsa.UsePublicKey(pubKey);

    success = rsa.VerifyStringENC(strData,"sha256",hexSig);
    if (success == true) {
        console.log("Signature verified!");
    }
    else {
        console.log(rsa.LastErrorText);
    }

    // Try it with an invalid signature:
    success = rsa.VerifyStringENC(strData,"sha256","not a valid sig");
    if (success == true) {
        console.log("Signature verified!");
    }
    else {
        console.log("Signature validation failed!");
    }

    // Try it with invalid data:
    success = rsa.VerifyStringENC("Not the original data","sha256",hexSig);
    if (success == true) {
        console.log("Signature verified!");
    }
    else {
        console.log("Signature validation failed!");
    }


}

chilkatExample();