www-apps/pmwiki/cookbook/AesCrypt/JavaAesCryptTest/src/main/java/org/pmwiki/cookbook/aescrypt/AesCrypto.java

   1 /*
   2  * To change this template, choose Tools | Templates
   3  * and open the template in the editor.
   4  */
   5
   6 package org.pmwiki.cookbook.aescrypt;
   7
   8 import java.security.SecureRandom;
   9 import java.util.Random;
  10 import javax.crypto.Cipher;
  11 import javax.crypto.spec.IvParameterSpec;
  12 import javax.crypto.spec.SecretKeySpec;
  13 import org.apache.commons.codec.binary.Base64;
  14 import org.apache.commons.codec.binary.Hex;
  15 import org.apache.commons.codec.digest.DigestUtils;
  16
  17 /**
  18  *
  19  * @author ludek
  20  * @author $Author$
  21  * @version $Rev$
  22  */
  23 public class AesCrypto {
  24
  25     public static final byte[] ZERO_NONCE = new byte[16];
  26
  27     public static final byte[] ONE_NONCE = new byte[] {
  28         0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1
  29     };
  30
  31     public static final int BITS = 256;
  32
  33     public static byte[] randomNonce() {
  34
  35         Random r = new SecureRandom();
  36         byte[] nonce = new byte[16];
  37         for (int i = 0; i < 8; i++) {
  38             nonce[i] = (byte) r.nextInt();
  39         }
  40         return nonce;
  41     }
  42
  43     public static byte[] encrypt(String plaintext, String password, byte[] nonce, KDF kdf) throws Exception
  44     {
  45         return encrypt(plaintext, kdf.getKey(password, BITS, nonce), nonce);
  46     }
  47
  48     public static String encryptToBase64(String plaintext, String password, byte[] nonce, KDF kdf) throws Exception
  49     {
  50
  51         return Base64.encodeBase64String(encrypt(plaintext, password, nonce, kdf)).trim();
  52     }
  53
  54     public static byte[] encrypt(String plaintext, byte[] keyData, byte[] nonce) throws Exception
  55     {
  56
  57         SecretKeySpec key = new SecretKeySpec(keyData, "AES");
  58
  59         Cipher cipher = Cipher.getInstance("AES/CTR/NoPadding");
  60         IvParameterSpec ivSpec = new IvParameterSpec(nonce);
  61         cipher.init(Cipher.ENCRYPT_MODE, key, ivSpec);
  62         byte[] resultData = cipher.doFinal(plaintext.getBytes());
  63
  64         byte enc[] = new byte[8 + resultData.length];
  65
  66         System.arraycopy(nonce, 0, enc, 0, 8);
  67         System.arraycopy(resultData, 0, enc, 8, resultData.length);
  68
  69         System.out.println(Hex.encodeHexString(enc));
  70         System.out.println(Base64.encodeBase64String(enc));
  71         return enc;
  72     }
  73
  74     public static String decrypt(byte[] cipher, String password, byte[] nonce, KDF kdf) throws Exception
  75     {
  76
  77         return decrypt(cipher, kdf.getKey(password, BITS, nonce), nonce);
  78     }
  79
  80     public static String decryptFromBase64(String ciphertext, String password, KDF kdf) throws Exception
  81     {
  82
  83         byte[] dataIn = Base64.decodeBase64(ciphertext);
  84         byte[] nonce = new byte[16];
  85
  86         byte enc[] = new byte[dataIn.length - 8];
  87
  88         System.arraycopy(dataIn, 0, nonce, 0, 8);
  89         System.arraycopy(dataIn, 8, enc, 0, dataIn.length - 8);
  90
  91         return decrypt(enc, password, nonce, kdf);
  92     }
  93
  94     public static String decryptFromBase64RawKey(String ciphertext, byte[] keyData) throws Exception
  95     {
  96
  97         byte[] dataIn = Base64.decodeBase64(ciphertext);
  98         byte[] nonce = new byte[16];
  99
 100         byte enc[] = new byte[dataIn.length - 8];
 101
 102         System.arraycopy(dataIn, 0, nonce, 0, 8);
 103         System.arraycopy(dataIn, 8, enc, 0, dataIn.length - 8);
 104
 105         return decrypt(enc, keyData, nonce);
 106     }
 107
 108     public static String decrypt(byte[] ciphertext, byte[] keyData, byte[] nonce) throws Exception
 109     {
 110
 111         SecretKeySpec key = new SecretKeySpec(keyData, "AES");
 112
 113         Cipher cipher = Cipher.getInstance("AES/CTR/NoPadding");
 114         IvParameterSpec ivSpec = new IvParameterSpec(nonce);
 115         cipher.init(Cipher.DECRYPT_MODE, key, ivSpec);
 116         byte[] resultData = cipher.doFinal(ciphertext);
 117         System.out.println(new String(resultData));
 118         return new String(resultData);
 119     }
 120
 121
 122 }