Java Tutorial/Security/SecretKey

Create a 192 bit secret key from raw bytes

   <source lang="java">

import javax.crypto.Cipher; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec; public class MainClass {

 public static void main(String[] args) throws Exception {
   byte[] data = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07 };
   Cipher c = Cipher.getInstance("Blowfish/ECB/NoPadding");
   SecretKey key192 = new SecretKeySpec(new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
       0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
       0x16, 0x17 }, "Blowfish");
   c.init(Cipher.ENCRYPT_MODE, key192);
   c.doFinal(data);
 }

}</source>

Create a 64 bit secret key from raw bytes

   <source lang="java">

import javax.crypto.Cipher; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec; public class MainClass {

 public static void main(String[] args) throws Exception {
   byte[] data = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07 };
   SecretKey key64 = new SecretKeySpec(
       new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07 }, "Blowfish");
   Cipher c = Cipher.getInstance("Blowfish/ECB/NoPadding");
   c.init(Cipher.ENCRYPT_MODE, key64);
   c.doFinal(data);
 }

}</source>

Create SecretKey

   <source lang="java">

import java.security.Key; import javax.crypto.Cipher; import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; import javax.crypto.SecretKeyFactory; import javax.crypto.spec.PBEKeySpec; import javax.crypto.spec.PBEParameterSpec; public class MainClass {

 public static void main(String[] args) throws Exception {
   KeyGenerator kg = KeyGenerator.getInstance("DESede");
   Key sharedKey = kg.generateKey();
   String password = "password";
   byte[] salt = "salt1234".getBytes();
   PBEParameterSpec paramSpec = new PBEParameterSpec(salt, 20);
   PBEKeySpec keySpec = new PBEKeySpec(password.toCharArray());
   SecretKeyFactory kf = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
   SecretKey passwordKey = kf.generateSecret(keySpec);
   Cipher c = Cipher.getInstance("PBEWithMD5AndDES");
   c.init(Cipher.WRAP_MODE, passwordKey, paramSpec);
   byte[] wrappedKey = c.wrap(sharedKey);
   c = Cipher.getInstance("DESede");
   c.init(Cipher.ENCRYPT_MODE, sharedKey);
   byte[] input = "input".getBytes();
   byte[] encrypted = c.doFinal(input);
   c = Cipher.getInstance("PBEWithMD5AndDES");
   c.init(Cipher.UNWRAP_MODE, passwordKey, paramSpec);
   Key unwrappedKey = c.unwrap(wrappedKey, "DESede", Cipher.SECRET_KEY);
   c = Cipher.getInstance("DESede");
   c.init(Cipher.DECRYPT_MODE, unwrappedKey);
   System.out.println(new String(c.doFinal(encrypted)));
 }

}</source>

implements SecretKey

   <source lang="java">

import javax.crypto.SecretKey; public class XORKey implements SecretKey {

 int rotValue;
 XORKey(int value) {
   rotValue = value;
 }
 public String getAlgorithm() {
   return "XOR";
 }
 public String getFormat() {
   return "XOR Special Format";
 }
 public byte[] getEncoded() {
   byte b[] = new byte[4];
   b[3] = (byte) ((rotValue << 24) & 0xff);
   b[2] = (byte) ((rotValue << 16) & 0xff);
   b[1] = (byte) ((rotValue << 8) & 0xff);
   b[0] = (byte) ((rotValue << 0) & 0xff);
   return b;
 }

}</source>