[android-developers] Android/JVM difference in RSA decryption

[Joseph]

I am trying to decrypt a String, that I have encrypted elsewhere. Here
is my code:

private void test() {

    try {
        String
stringMessage="Sf3O7Lr2+WN5szGyLejL3CjuBRZtQ72+ZBmgVTgWnatQZxUElzaBqFa1p0SVBqe9VWVxCxdEkejMVtDGEr0UJSVSK8EB/
fPI6v8JE8dIu0JN0mMs4xlowhITy0tQR+1pcBtDFjzOl33xxQcq5JuPezxRDxFIp
+IVkD8FdpqlttEKf2Tvqw9tqsdgiBKb5xDvKrkIDQXdLBh1gbAVZDSJYGHRkcOA8vz2ty/
PeooKkfDK6IOn7KBwOBgSRgQr/MLBF3Xk2vRWgVGRh/fRkzu21EWo99Q5moWKxWl3HW/
bbgTBQTb097XP3NTID9kSPhCfL0BEfBxonuNse5GBoeRnCw==";
        //Convert String back to Byte[] and decrpt
        byte[] byteMessage =
Base64.decodeBase64(stringMessage.getBytes("UTF-8"));
        System.out.println("ENCRYPTED MESSAGE byte Length:
"+byteMessage.length);

        String decryptedMsg = decryptString(byteMessage,
loadCASPrivateKey());
        System.out.println(decryptedMsg);
    } catch (Exception e) {
        e.printStackTrace();
        return;
    }
}

private static String decryptString(byte[] message, Key privateKey)
throws InvalidKeyException, NoSuchAlgorithmException,
NoSuchPaddingException, IllegalBlockSizeException,
BadPaddingException, UnsupportedEncodingException {
    Cipher cipher = Cipher.getInstance("RSA");
    cipher.init(Cipher.DECRYPT_MODE, privateKey);

    byte[] cipherData = cipher.doFinal(message);
    return new String(cipherData, "UTF-8");
}

private PrivateKey loadCASPrivateKey() throws IOException,
NoSuchAlgorithmException, InvalidKeySpecException {
    InputStream is = getClass().getResourceAsStream( "/keys/app-
private.key" );
    if (is == null) {
        System.out.println("NULL");
    }
    byte[] encodedPrivateKey = new byte[(int) 2000];
    is.read(encodedPrivateKey);
    is.close();

    // Generate KeyPair.
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");

    PKCS8EncodedKeySpec privateKeySpec = new
PKCS8EncodedKeySpec(encodedPrivateKey);
    PrivateKey privateKey =
keyFactory.generatePrivate(privateKeySpec);

    return privateKey;

}
This works 100% how I would like it to under my desktop JVM, however
when I run it in the Android emulator I get:

04-24 22:42:21.011: I/System.out(1041): ��k���_��*�ݣ���93|
@0�̍4�y)��Q�k�;*A����e�#��A� �oiu:�����W5@$�w�j��uS�R�Ocxٰ&����l �w'/
�d�8uA��ؔ�{�4$�U�0��{Ԑ��t!9��n�� ��a��'Jdt2�t�T�D��k+k�;������ ����GF��
\�rڼ��>]�y+^w�<�� ��'E{�8R]�ZHyu��ζ��軟�ށ掱�{�A�#ȟ�

I assume my problem is down to encoding, but I've spent all day trying
to work out what and am really stumped.

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