AESEncoder class is not supported on j2me chinese phone - encryption

Question

I am using this encryption class in a J2ME app. My J2ME application works fine on all Nokia devices. The app doesn't work on the Chinese MIw200 phone. Perhaps this cryptography is not supported on that phone? Is there another solution or any other method to encrypt and decrypt?
Please help me. Thanks a lot in advance.
My code is below:
import java.security.NoSuchAlgorithmException;
import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.SecretKeySpec;
public class AESEncoder {
private SecretKeySpec keyspec;
private Cipher cipher;
private String secretkey;
public AESEncoder(String secretkey) {
this.secretkey = secretkey;
keyspec = new SecretKeySpec(secretkey.getBytes(), 0, 16, "AES");
// keyspec=new SecretKeySpec(key, offset, len, secretkey);
try {
cipher = Cipher.getInstance("AES/ECB/NoPadding");
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
}
}
public byte[] encrypt(String text) throws Exception {
if (text == null || text.length() == 0) {
throw new Exception("Empty string");
}
int encrypted = 0;
byte[] bytenc = null;//new byte[32];
byte[] input = null;
try {
cipher.init(Cipher.ENCRYPT_MODE, keyspec);
// byte empty[]=padString(text).getBytes();
// encrypted = cipher.doFinal(padString(text).getBytes());
// encrypted=cipher.doFinal(padString(text).getBytes(), 0, 0, padString(text).getBytes(), 0);
input = padString(text).getBytes();
bytenc = new byte[input.length];
encrypted = cipher.doFinal(input, 0, input.length, bytenc, 0);
String str = new String(bytenc, 0, encrypted);
// encrypted=cipher.update(padString(text).getBytes(), 0, 0, 0, 0);
// System.out.println("Encrypted is:>>" + str);
// bytenc=hexToBytes(String.valueOf(encrypted));
} catch (Exception e) {
throw new Exception("[encrypt] " + e.getMessage());
}
return bytenc;
}
public String encrypt_hsm(String text) throws Exception {
if (text == null || text.length() == 0) {
throw new Exception("Empty string");
}
String base64=null;
int encrypted = 0;
byte[] bytenc = null;//new byte[32];
byte[] input = null;
try {
cipher.init(Cipher.ENCRYPT_MODE, keyspec);
// byte empty[]=padString(text).getBytes();
// encrypted = cipher.doFinal(padString(text).getBytes());
// encrypted=cipher.doFinal(padString(text).getBytes(), 0, 0, padString(text).getBytes(), 0);
input = padString(text).getBytes();
bytenc = new byte[input.length];
encrypted = cipher.doFinal(input, 0, input.length, bytenc, 0);
String str = new String(bytenc, 0, encrypted);
base64 = Base64.encode(bytenc);
// encrypted=cipher.update(padString(text).getBytes(), 0, 0, 0, 0);
// System.out.println("Encrypted is:>>" + str);
// bytenc=hexToBytes(String.valueOf(encrypted));
} catch (Exception e) {
throw new Exception("[encrypt] " + e.getMessage());
}
return base64;
}
public byte[] decrypt(String code) throws Exception {
if (code == null || code.length() == 0) {
throw new Exception("Empty string");
}
int decrypted = 0;
byte[] bytedec = null;
byte[] input = null;
try {
cipher.init(Cipher.DECRYPT_MODE, keyspec);
// input=hexToBytes(code);
input = Base64ToBytes(code);
bytedec = new byte[input.length];
decrypted = cipher.doFinal(input, 0, input.length, bytedec, 0);
String str = new String(bytedec, 0, decrypted);
// System.out.println("Decrypted is:>>" + str);
} catch (Exception e) {
throw new Exception("[decrypt] " + e.getMessage());
}
return bytedec;
}
public static String bytesToHex(byte[] bsData) {
int nDataLen = bsData.length;
String sHex = "";
for (int nIter = 0; nIter < nDataLen; nIter++) {
int nValue = (bsData[nIter] + 256) % 256;
int nIndex1 = nValue >> 4;
sHex += Integer.toHexString(nIndex1);
int nIndex2 = nValue & 0x0f;
sHex += Integer.toHexString(nIndex2);
}
return sHex;
}
public static byte[] hexToBytes(String str) {
if (str == null) {
return null;
} else if (str.length() < 2) {
return null;
} else {
int len = str.length() / 2;
byte[] buffer = new byte[len];
for (int i = 0; i < len; i++) {
buffer[i] = (byte) Integer.parseInt(str.substring(i * 2, i * 2 + 2), 16);
}
return buffer;
}
}
private static String padString(String source) {
char paddingChar = ' ';
int size = 32;
int x = source.length() % size;
int padLength = size - x;
for (int i = 0; i < padLength; i++) {
source += paddingChar;
}
// System.out.println("====>Pad String:" + source);
return source;
}
public void startApp() {
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
private byte[] Base64ToBytes(String code) {
code = code.replace('-', '+');
code = code.replace('_', '/');
code = code.replace(',', '=');
System.out.println("Final Base 64:"+code);
byte[] aesString = Base64.decode(code);
// System.out.println("Base64 after decoding:"+new String(aesString));
return aesString;
}
}

Answer 1

Please post a stack trace. Otherwise we are all just guessing.
AES is a required cipher, sometime between v4 and v7. Spend some time and confirm that this cipher isn't available on the MIw200.
Someone getting "AES not available" on a Mac got some suggestions.
Try allowing the system to fall back to 3DES or DES, instead of forcing AES. Here's an example that tests encryption with each algorithm.
Try using the BouncyCastle API. Here is a how-to guide.