2g0Kj4Jt

1package javaapplication47;
2
3import java.security.InvalidAlgorithmParameterException;
4import java.security.Key; 
5import java.security.KeyPair; 
6import java.security.KeyPairGenerator; 
7import java.security.Security; 
8import java.security.SecureRandom; 
9import javax.crypto.Cipher; 
10 
11import java.security.InvalidKeyException; 
12import java.security.NoSuchAlgorithmException; 
13import java.security.spec.InvalidKeySpecException;
14import javax.crypto.BadPaddingException; 
15import javax.crypto.IllegalBlockSizeException; 
16import javax.crypto.NoSuchPaddingException; 
17import javax.crypto.SecretKey;
18import javax.crypto.SecretKeyFactory;
19import javax.crypto.ShortBufferException; 
20import javax.crypto.spec.PBEKeySpec;
21import javax.crypto.spec.SecretKeySpec; 
22import javax.rmi.CORBA.Util; 
23
24
25public class JavaApplication47 {
26
27    /**
28     * @param args the command line arguments
29     */
30    public static void main(String[] args) throws InvalidKeyException, NoSuchPaddingException, NoSuchPaddingException, ShortBufferException, IllegalBlockSizeException, BadPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeySpecException {
31        byte[] keyBytes = new byte[16]; 
32        // declare secure PRNG 
33        SecureRandom myPRNGCBC = new SecureRandom(); 
34        // seed the key 
35        myPRNGCBC.nextBytes(keyBytes); 
36        // build the key from random key bytes 
37        SecretKeySpec myKeyCBC = new SecretKeySpec(keyBytes, "AES"); 
38        // instantiate AES object for ECB with no padding 
39        Cipher myAESCBC = Cipher.getInstance("AES/CBC/NoPadding"); 
40        // initialize AES objecy to encrypt mode 
41        myAESCBC.init(Cipher.ENCRYPT_MODE, myKeyCBC); 
42        // initialize plaintext 0
43        byte[] plaintext = new byte[32];
44        plaintext[0] = 'Z';
45        plaintext[1] = 'S';
46        plaintext[2] = 'O';
47        plaintext[3] = 'L';
48        plaintext[4] = 'T';
49        plaintext[5] = 6;
50        plaintext[6] = 9;
51        
52        //initialize ciphertext 
53        byte[] ciphertextCBC = new byte[32]; 
54        byte[] ciphertextCFB = new byte[32];
55        byte[] ciphertextOFB = new byte[32];
56
57        
58        
59        
60        SecureRandom myPRNGOFB = new SecureRandom(); 
61        // seed the key 
62        myPRNGOFB.nextBytes(keyBytes); 
63        // build the key from random key bytes 
64        SecretKeySpec myKeyOFB = new SecretKeySpec(keyBytes, "AES"); 
65        // instantiate AES object for ECB with no padding 
66        Cipher myAESOFB = Cipher.getInstance("AES/OFB/NoPadding"); 
67        // initialize AES objecy to encrypt mode 
68        myAESOFB.init(Cipher.ENCRYPT_MODE, myKeyOFB); 
69        // initialize plaintext 0
70        
71                
72        SecureRandom myPRNGCFB = new SecureRandom(); 
73        // seed the key 
74        myPRNGCFB.nextBytes(keyBytes); 
75        // build the key from random key bytes 
76        SecretKeySpec myKeyCFB = new     SecretKeySpec(keyBytes, "AES"); 
77        // instantiate AES object for ECB with no padding 
78        Cipher myAESCFB = Cipher.getInstance("AES/OFB/NoPadding"); 
79        // initialize AES objecy to encrypt mode 
80        myAESCFB.init(Cipher.ENCRYPT_MODE, myKeyCFB); 
81        // initialize plaintext 0
82     
83     
84        System.out.println("plaintext: " + javax.xml.bind.DatatypeConverter.printHexBinary(plaintext)); 
85
86        // initialize AES for decryption 
87        int cLengthCBC = myAESCBC.update(plaintext, 0, plaintext.length, ciphertextCBC, 0);
88        myAESCBC.init(Cipher.DECRYPT_MODE, myKeyCBC, myAESCBC.getParameters()); 
89        // initialize a new array of bytes to place the decryption 
90        byte[] dec_plaintextCBC = new byte[32]; 
91        cLengthCBC = myAESCBC.update(ciphertextCBC, 0, ciphertextCBC.length, dec_plaintextCBC, 0); 
92        // process remaining blocks of ciphertext 
93        cLengthCBC += myAESCBC.doFinal(dec_plaintextCBC, cLengthCBC); 
94        // print the new plaintext (hopefully identical to the initial one) 
95        System.out.println("ciphertext: " + javax.xml.bind.DatatypeConverter.printHexBinary(ciphertextCBC)); 
96        System.out.println("decrypted: " + javax.xml.bind.DatatypeConverter.printHexBinary(dec_plaintextCBC)); 
97        
98        
99
100        int cLengthOFB = myAESOFB.update(plaintext, 0, plaintext.length, ciphertextOFB, 0);
101        myAESOFB.init(Cipher.DECRYPT_MODE, myKeyOFB, myAESOFB.getParameters()); 
102        // initialize a new array of bytes to place the decryption 
103        byte[] dec_plaintextOFB = new byte[32]; 
104        cLengthOFB = myAESOFB.update(ciphertextOFB, 0, ciphertextOFB.length, dec_plaintextOFB, 0); 
105        // process remaining blocks of ciphertext 
106        cLengthOFB += myAESOFB.doFinal(dec_plaintextOFB, cLengthOFB); 
107        // print the new plaintext (hopefully identical to the initial one) 
108        System.out.println("ciphertext: " + javax.xml.bind.DatatypeConverter.printHexBinary(ciphertextOFB)); 
109        System.out.println("decrypted: " + javax.xml.bind.DatatypeConverter.printHexBinary(dec_plaintextOFB)); 
110        
111        
112        int cLengthCFB = myAESCFB.update(plaintext, 0, plaintext.length, ciphertextCFB, 0);
113        myAESCFB.init(Cipher.DECRYPT_MODE, myKeyCFB, myAESCFB.getParameters()); 
114        // initialize a new array of bytes to place the decryption 
115        byte[] dec_plaintextCFB = new byte[32]; 
116        cLengthCFB = myAESCFB.update(ciphertextCFB, 0, ciphertextCFB.length, dec_plaintextCFB, 0); 
117        // process remaining blocks of ciphertext 
118        cLengthCFB += myAESCFB.doFinal(dec_plaintextCFB, cLengthCFB); 
119        // print the new plaintext (hopefully identical to the initial one) 
120        System.out.println("ciphertext: " + javax.xml.bind.DatatypeConverter.printHexBinary(ciphertextCFB));
121        System.out.println("decrypted: " + javax.xml.bind.DatatypeConverter.printHexBinary(dec_plaintextCFB));
122        
123        
124        char[] password = "short_password".toCharArray(); 
125        byte[] salt = new byte[16]; 
126        int iteration_count = 10000; 
127        
128        
129        int key_size = 128; 
130        // set salt values to random
131        SecureRandom myPRNG = new SecureRandom();
132        myPRNG.nextBytes(salt); 
133
134        // initialize key factory for HMAC-SHA1 derivation 
135        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");             
136        // set key specification 
137        PBEKeySpec pbekSpec = new PBEKeySpec(password, salt, iteration_count, key_size); 
138        // generate the key 
139        SecretKey myAESPBKey = new SecretKeySpec( keyFactory.generateSecret(pbekSpec).getEncoded(), "AES"); 
140        // print the key 
141        System.out.println("AES key: " + javax.xml.bind.DatatypeConverter.printHexBinary(myAESPBKey.getEncoded())); 
142        
143        Cipher myAES = Cipher.getInstance("AES/OFB/NoPadding"); 
144        // initialize AES objecy to encrypt mode 
145        myAES.init(Cipher.ENCRYPT_MODE, myAESPBKey);
146        myAES.init(Cipher.DECRYPT_MODE, myAESPBKey,myAES.getParameters());
147        
148        
149        
150    }
151    
152}