React Native

RSA Sign using a Private Key on a USB Token or Smartcard

See more Apple Keychain Examples

Create an RSA signature using a private key stored on a USB token or smartcard.

Note: On MacOS and iOS, this example requires Chilkat v10.1.2 or later when the Apple Keychain is used as the underlying means to do the signing.

React Native

import { BinData, Cert, Rsa } from '@chilkat/react-native'

function chilkatExample() {
  // Assuming the smartcard/USB token is installed with the correct drivers from the manufacturer,
  // this code can work on multiple platforms including Windows, MacOS, Linux, and iOS.

  // Chilkat automatically detects and determines the way in which the HSM is used,
  // which can be by PKCS11, Apple Keychain, Microsoft CNG / Crypto API, or ScMinidriver.

  const cert = new Cert();

  // Set the token/smartcard PIN prior to loading.
  cert.smartCardPin = '123456';

  // Specify the certificate by its common name.
  try {
    cert.loadFromSmartcard('cn=chilkat-rsa-2048');
  } catch {
    console.log(cert.lastErrorText);
    return;
  }

  console.log(`Signing with cert: ${cert.subjectCN}`);

  // Create data to be hashed and signed.
  const bd = new BinData();
  for (let i = 0; i <= 100; i++) {
    bd.appendEncoded('000102030405060708090A0B0C0D0E0F', 'hex');
  }

  const rsa = new Rsa();

  // Use the certificate's private key for signing.
  try {
    rsa.setX509Cert(cert, true);
  } catch {
    console.log(rsa.lastErrorText);
    return;
  }

  // Sign the SHA-256 hash of the contents of bd.
  const bdSig = new BinData();
  try {
    rsa.signBd(bd, 'sha256', bdSig);
  } catch {
    console.log(rsa.lastErrorText);
    return;
  }

  // The RSA signature is equal in length to the size of the RSA key.
  console.log(`Output signature size in bits = ${bdSig.numBytes * 8}`);

  // We can save the signature for later verification..
  bdSig.writeFile('rsaSignatures/test1.sig');

  // See the example to verify the RSA signature:
  // Verfies an RSA Signature
}