Dart

PKCS7 Sign Text using RSA 2048, SHA256, Base64 Output

See more Digital Signatures Examples

Demonstrates how to sign text using 2048-bit RSA with SHA256, producing PKCS#7 output in Base64. The certificate w/ private key used for signing is loaded from a .p12/.pfx file. Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // This example requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  final cert = CkCert();

  // Load the cert and private key.  Whatever the private key happens to be,
  // such as RSA or ECC, then Chilkat will use it.  If the private key is 
  // a 2048-bit RSA key, then that's what will be used..
  try {
    cert.loadPfxFile('qa_data/pfx/myCertAndKey.p12', 'password');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final crypt = CkCrypt2();

  try {
    crypt.setSigningCert(cert);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Use SHA-256
  crypt.hashAlgorithm = 'sha256';

  // Hash the utf-8 byte representation of the string
  crypt.charset = 'utf-8';

  // Return the result in base64
  crypt.encodingMode = 'base64';

  // Sign some text..
  final textToSign = 'This is the text to be hashed and signed.';
  final String sigBase64;
  try {
    sigBase64 = crypt.opaqueSignStringENC(textToSign);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print(sigBase64);

  // The result:
  // MIIS2wYJKoZIhvcNAQc ... zGeeY4Oxg==
}