gGPxkN7y

1package encryption;
2
3import java.io.BufferedReader;
4import java.io.BufferedWriter;
5import java.io.FileReader;
6import java.io.FileWriter;
7import java.io.IOException;
8import java.io.UnsupportedEncodingException;
9
10import java.security.AlgorithmParameters;
11import java.security.InvalidAlgorithmParameterException;
12import java.security.InvalidKeyException;
13import java.security.NoSuchAlgorithmException;
14import java.security.spec.InvalidKeySpecException;
15import java.security.spec.InvalidParameterSpecException;
16import java.security.spec.KeySpec;
17
18import java.util.logging.Level;
19import java.util.logging.Logger;
20
21import javax.crypto.BadPaddingException;
22import javax.crypto.Cipher;
23import javax.crypto.IllegalBlockSizeException;
24import javax.crypto.NoSuchPaddingException;
25import javax.crypto.SecretKey;
26import javax.crypto.SecretKeyFactory;
27import javax.crypto.spec.IvParameterSpec;
28import javax.crypto.spec.PBEKeySpec;
29import javax.crypto.spec.SecretKeySpec;
30
31/**
32 *
33 * @author jaredb
34 */
35public class PBE {
36    
37    public static SecretKey deriveKey(String password, byte[] salt) {
38        try {
39            SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256");
40            KeySpec spec = new PBEKeySpec(password.toCharArray(), salt, 65536, 256);
41            SecretKey tmp = factory.generateSecret(spec);
42            SecretKey secret = new SecretKeySpec(tmp.getEncoded(), "AES");
43            
44            return secret;
45        } catch (NoSuchAlgorithmException | InvalidKeySpecException ex) {
46            Logger.getLogger(PBE.class.getName()).log(Level.SEVERE, null, ex);
47        }
48        
49        return null;
50    }
51    
52    public static String encrypt(String plainText, SecretKey secret) {
53        try {
54            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
55            cipher.init(Cipher.ENCRYPT_MODE, secret);
56            
57            AlgorithmParameters params = cipher.getParameters();
58            byte[] iv = params.getParameterSpec(IvParameterSpec.class).getIV();
59            byte[] ciphertext = cipher.doFinal(plainText.getBytes("UTF-8"));
60            
61            String cipherString = new String(ciphertext);
62            String ivString = new String(iv);
63            
64            try(BufferedWriter writer = new BufferedWriter(new FileWriter("stored.txt"))) {
65                writer.write(cipherString + ":" + ivString);
66            } catch(IOException ex) {
67                System.out.println(ex.getMessage());
68            }
69            
70            return cipherString;
71        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | InvalidParameterSpecException | UnsupportedEncodingException | IllegalBlockSizeException | BadPaddingException ex) {
72            Logger.getLogger(PBE.class.getName()).log(Level.SEVERE, null, ex);
73        }
74        
75        return null;
76    }
77    
78    public static String decrypt(String cipherText, SecretKey secret) {
79        byte[] iv = null;
80        
81        try(BufferedReader reader = new BufferedReader(new FileReader("stored.txt"))) {
82            String line;
83            
84            while((line = reader.readLine()) != null) {
85                cipherText = line.split(":")[0];
86                iv = line.split(":")[1].getBytes();
87            }
88        } catch(IOException ex) {
89            System.out.println(ex.getMessage());
90        }
91        
92        try {
93            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
94            cipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(iv));
95            
96            String plaintext = new String(cipher.doFinal(cipherText.getBytes()), "UTF-8");
97            return plaintext;
98        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | InvalidAlgorithmParameterException | IllegalBlockSizeException | BadPaddingException | UnsupportedEncodingException ex) {
99            Logger.getLogger(PBE.class.getName()).log(Level.SEVERE, null, ex);
100        }
101        
102        return null;
103    }
104    
105}