To create this app, I use 3 classes. The first class is an activity called AesMd5.java, GenerateAes.java, Md5Baru.java.
For the source code to create this simple apps I'll show below.
The first is
AesMd5.java
package org.aesmd5;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.*;
import android.widget.Button;
import android.widget.EditText;
public class AesMd5 extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_aes_md5);
final Button enkripButton = (Button)findViewById(R.id.enkrip_button);
final EditText inputKunci = (EditText)findViewById(R.id.input_kunci);
final EditText inputKata = (EditText)findViewById(R.id.input_kata);
final EditText teksEnkrip = (EditText)findViewById(R.id.teks_enkrip);
// handling for Encryption
enkripButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
String ambilKunci = inputKunci.getText().toString();
String ambilKata = inputKata.getText().toString();
String enKata = "";
try {
enKata = GenerateAES.encrypt(ambilKunci, ambilKata);
} catch (Exception e) {
e.printStackTrace();
}
//teksEnkrip.setText(enKata);
teksEnkrip.setText(Md5Baru.MD5(enKata));
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_aes_md5, menu);
return true;
}
}
GenerateAes.java
package org.aesmd5;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.security.SecureRandom;
public class GenerateAES {
//private Cipher cipher;
//private SecretKeySpec sKey;
public GenerateAES() {
}
public static String encrypt(String seed, String cleartext) throws Exception {
byte[] rawKey = getRawKey(seed.getBytes());
byte[] result = encrypt(rawKey, cleartext.getBytes());
return toHex(result);
}
public static String decrypt(String seed, String encrypted) throws Exception {
byte[] rawKey = getRawKey(seed.getBytes());
byte[] enc = toByte(encrypted);
byte[] result = decrypt(rawKey, enc);
return new String(result);
}
private static byte[] getRawKey(byte[] seed) throws Exception {
KeyGenerator kgen = KeyGenerator.getInstance("AES");
SecureRandom sr = SecureRandom.getInstance("SHA1PRNG");
sr.setSeed(seed);
kgen.init(128, sr); // 192 and 256 bits may not be available
SecretKey skey = kgen.generateKey();
byte[] raw = skey.getEncoded();
return raw;
}
private static byte[] encrypt(byte[] raw, byte[] clear) throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
byte[] encrypted = cipher.doFinal(clear);
return encrypted;
}
private static byte[] decrypt(byte[] raw, byte[] encrypted) throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, skeySpec);
byte[] decrypted = cipher.doFinal(encrypted);
return decrypted;
}
public static String toHex(String txt) {
return toHex(txt.getBytes());
}
public static byte[] toByte(String hexString) {
int len = hexString.length()/2;
byte[] result = new byte[len];
for (int i = 0; i < len; i++)
result[i] = Integer.valueOf(hexString.substring(2*i, 2*i+2), 16).byteValue();
return result;
}
public static String toHex(byte[] buf) {
if (buf == null)
return "";
StringBuffer result = new StringBuffer(2*buf.length);
for (int i = 0; i < buf.length; i++) {
appendHex(result, buf[i]);
}
return result.toString();
}
private final static String HEX = "0123456789ABCDEF";
private static void appendHex(StringBuffer sb, byte b) {
sb.append(HEX.charAt((b>>4)&0x0f)).append(HEX.charAt(b&0x0f));
}
}
Md5Baru.java
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package org.aesmd5;
import java.security.*;
/**
*
* @author nang
*/
public class Md5Baru {
public static String MD5(String text) {
String md5 = "";
byte test[] = text.getBytes();
int panjang = 16;
byte[] mesDig = new byte[panjang];
try {
MessageDigest mD = MessageDigest.getInstance("MD5");
mD.reset();
mD.update(text.getBytes(), 0, text.length());
mD.digest(mesDig, 0, panjang);
StringBuffer sB = new StringBuffer();
for(int i=0; i<mesDig.length;i++) {
//mesDig = mD.digest(test, 0, test.length);
String hex = Integer.toHexString(0xFF & mesDig[i]);
if(hex.length() == 1) {
sB.append('0');
}
sB.append(hex);
}
md5 = sB.toString();
} catch (Exception e){
}
return md5;
}
}
And the last is activity_aes_md5.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:id="@+id/teks_kunci"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Masukkan kunci"
/>
<EditText
android:id="@+id/input_kunci"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<TextView
android:id="@+id/teks_kata"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Masukkan kata"
/>
<EditText
android:id="@+id/input_kata"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<Button
android:id="@+id/enkrip_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Enkrip"
/>
<EditText
android:id="@+id/teks_enkrip"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
Ok, that's all for today, happy coding, and go Open Source.
