Dart Requires Chilkat v11.0.0+

RSA Encrypt with SHA-256 hash function and SHA-256 mask function

See more RSA Examples

How can this Javascript be duplicated using Chilkat?

function a(e, t) {
                var r = s.pki.publicKeyFromPem(e)
                  , n = r.encrypt(t, "RSA-OAEP", {
                    md: s.md.sha256.create(),
                    mgf1: {
                        md: s.md.sha1.create()
                    }
                });
                return s.util.encode64(n)
            }

Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens, even using the same data and key, the result will be different -- but still valid. One should not expect to get the same output.

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 pubkey = CkPublicKey();

  final sbPem = CkStringBuilder();
  final bCrlf = true;
  sbPem.appendLine('-----BEGIN PUBLIC KEY-----', bCrlf);
  sbPem.appendLine('MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA33TqqLR3eeUmDtHS89qF', bCrlf);
  sbPem.appendLine('3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA', bCrlf);
  sbPem.appendLine('04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7s', bCrlf);
  sbPem.appendLine('Jp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwF', bCrlf);
  sbPem.appendLine('wnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUE', bCrlf);
  sbPem.appendLine('f0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1W', bCrlf);
  sbPem.appendLine('SwIDAQAB', bCrlf);
  sbPem.appendLine('-----END PUBLIC KEY-----', bCrlf);

  // Load the public key object from the PEM. 
  try {
    pubkey.loadFromString(sbPem.getAsString());
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final originalData = 'This is the original data to be SHA-256 hashed and RSA encrypted.';

  // First we SHA-256 hash the original data.
  final crypt = CkCrypt2();
  crypt.hashAlgorithm = 'SHA-256';
  final hashBytes = crypt.hashString(originalData);

  // Now to RSA encrypt using OAEP padding with SHA-256 for the mask function.
  final rsa = CkRsa();
  rsa.pkcsPadding = false;
  rsa.oaepHash = 'SHA256';
  rsa.usePublicKey(pubkey);
  rsa.encodingMode = 'base64';

  // Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens,
  // even using the same data and key, the result will be different --  but still valid.  One should not expect
  // to get the same output.
  final bUsePrivateKey = false;
  final String encryptedStr;
  try {
    encryptedStr = rsa.encryptBytesENC(hashBytes, bUsePrivateKey);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('Base64 RSA encrypted output: $encryptedStr');
}