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1package encriptionusingpbkgkey;
2
3import java.security.Key;
4import java.security.KeyPair;
5import java.security.KeyPairGenerator;
6import java.security.Security;
7import java.security.SecureRandom;
8import javax.crypto.Cipher;
9import javax.crypto.SecretKeyFactory;
10import javax.crypto.SecretKey;
11
12import java.security.InvalidKeyException;
13import java.security.NoSuchAlgorithmException;
14import java.security.spec.InvalidKeySpecException;
15import javax.crypto.BadPaddingException;
16import javax.crypto.IllegalBlockSizeException;
17import javax.crypto.NoSuchPaddingException;
18import javax.crypto.ShortBufferException;
19import javax.crypto.interfaces.PBEKey;
20import javax.crypto.spec.PBEKeySpec;
21import javax.crypto.spec.SecretKeySpec;
22import javax.rmi.CORBA.Util;
23
24
25public class EncriptionUsingPBKGKey {
26
27    public static void CBC_enc() throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, ShortBufferException, IllegalBlockSizeException, BadPaddingException{
28        byte[] keyBytes = new byte[16];
29        // declare secure PRNG
30        SecureRandom myPRNG = new SecureRandom();
31        // seed the key
32        myPRNG.nextBytes(keyBytes);
33        // build the key from random key bytes
34        SecretKeySpec myKey = new SecretKeySpec(keyBytes, "AES");
35        // instantiate AES object for ECB with no padding
36        Cipher myAES = Cipher.getInstance("AES/CBC/NoPadding");
37        // initialize AES objecy to encrypt mode
38        myAES.init(Cipher.ENCRYPT_MODE, myKey);
39        // initialize plaintext
40        byte[] plaintext = new byte[16];
41        //initialize ciphertext
42        byte[] ciphertext = new byte[16];
43        // update cipher with the plaintext
44        int cLength = myAES.update(plaintext, 0, plaintext.length, ciphertext,0);
45        // process remaining blocks of plaintext
46        cLength += myAES.doFinal(ciphertext, cLength);
47        // print plaintext and ciphertext
48        System.out.println("plaintext: " +
49            javax.xml.bind.DatatypeConverter.printHexBinary(plaintext));
50        System.out.println("ciphertext: " +
51            javax.xml.bind.DatatypeConverter.printHexBinary(ciphertext));
52    }
53    
54    public static void encriptFromPBKG () throws NoSuchAlgorithmException, InvalidKeySpecException, NoSuchPaddingException, InvalidKeyException, ShortBufferException, IllegalBlockSizeException, BadPaddingException {
55        byte[] salt = new byte[16];
56        char[] password = "short_password".toCharArray();
57        int iterationCount = 10000;
58        int keySize = 128;
59        SecureRandom myPRNG = new SecureRandom();
60        myPRNG.nextBytes(salt);
61        
62        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
63        PBEKeySpec pbekSpec = new PBEKeySpec(password, salt, iterationCount, keySize);
64        SecretKey myAESPBKey = new SecretKeySpec(keyFactory.generateSecret(pbekSpec).getEncoded(), "AES");
65        System.out.println("AES key: " + javax.xml.bind.DatatypeConverter.printHexBinary(myAESPBKey.getEncoded()));
66        
67        Cipher myAES = Cipher.getInstance("AES/OFB/NoPadding");
68        // initialize AES objecy to encrypt mode
69        myAES.init(Cipher.ENCRYPT_MODE, myAESPBKey);
70        // initialize plaintext
71        byte[] plaintext = new byte[16];
72        //initialize ciphertext
73        byte[] ciphertext = new byte[16];
74        // update cipher with the plaintext
75        int cLength = myAES.update(plaintext, 0, plaintext.length, ciphertext,0);
76        // process remaining blocks of plaintext
77        cLength += myAES.doFinal(ciphertext, cLength);
78        // print plaintext and ciphertext
79        System.out.println("OFB encryption:\nplaintext: " +
80            javax.xml.bind.DatatypeConverter.printHexBinary(plaintext));
81        System.out.println("ciphertext: " +
82            javax.xml.bind.DatatypeConverter.printHexBinary(ciphertext));
83       
84        myAES = Cipher.getInstance("AES/CFB/NoPadding");
85        // initialize AES objecy to encrypt mode
86        myAES.init(Cipher.ENCRYPT_MODE, myAESPBKey);
87        // initialize plaintext
88        plaintext = new byte[16];
89        //initialize ciphertext
90        ciphertext = new byte[16];
91        // update cipher with the plaintext
92        cLength = myAES.update(plaintext, 0, plaintext.length, ciphertext,0);
93        // process remaining blocks of plaintext
94        cLength += myAES.doFinal(ciphertext, cLength);
95        // print plaintext and ciphertext
96        System.out.println("\nCFB encryption:\nplaintext: " +
97            javax.xml.bind.DatatypeConverter.printHexBinary(plaintext));
98        System.out.println("ciphertext: " +
99            javax.xml.bind.DatatypeConverter.printHexBinary(ciphertext));
100    }
101
102    public static void main(String[] args) throws NoSuchAlgorithmException, NoSuchPaddingException, ShortBufferException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException, InvalidKeySpecException{
103        System.out.println("CBC encription: ");
104        CBC_enc();
105        System.out.println();
106        encriptFromPBKG();
107    }
108    
109}