rs9Jm0ZD

1/*
2 * To change this license header, choose License Headers in Project Properties.
3 * To change this template file, choose Tools | Templates
4 * and open the template in the editor.
5 */
6package rebeca;
7
8import java.security.InvalidAlgorithmParameterException;
9import java.security.Key;
10import java.security.KeyPair;
11import java.security.KeyPairGenerator;
12import java.security.Security;
13import java.security.SecureRandom;
14import javax.crypto.Cipher;
15import java.security.InvalidKeyException;
16import java.security.NoSuchAlgorithmException;
17import java.security.spec.InvalidKeySpecException;
18import javax.crypto.BadPaddingException;
19import javax.crypto.IllegalBlockSizeException;
20import javax.crypto.NoSuchPaddingException;
21import javax.crypto.SecretKey;
22import javax.crypto.SecretKeyFactory;
23import javax.crypto.ShortBufferException;
24import javax.crypto.spec.IvParameterSpec;
25import javax.crypto.spec.PBEKeySpec;
26import javax.crypto.spec.SecretKeySpec;
27import javax.rmi.CORBA.Util;
28/**
29 *
30 * @author student
31 */
32public class Rebeca {
33
34    /**
35     * @param args the command line arguments
36     */
37    public static void main(String[] args) throws InvalidKeyException, ShortBufferException, IllegalBlockSizeException, BadPaddingException, NoSuchAlgorithmException, NoSuchPaddingException, InvalidAlgorithmParameterException, InvalidKeySpecException {
38        
39        byte[] keyBytes = new byte[16];
40        SecureRandom myPRNG = new SecureRandom();
41        IvParameterSpec ivparam = new IvParameterSpec(new byte[16]);
42        
43        char[] password = "short_password".toCharArray();
44        byte[] salt = new byte[16];
45        int iteration_count = 10000;
46        int key_size = 128;
47        // set salt values to random
48        myPRNG.nextBytes(salt);
49        // initialize key factory for HMAC-SHA1 derivation
50        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
51        // set key specification
52        PBEKeySpec pbekSpec = new PBEKeySpec(password, salt, iteration_count, key_size);
53        // generate the key
54        SecretKey myAESPBKey = new SecretKeySpec( keyFactory.generateSecret(pbekSpec).getEncoded(), "AES");
55        //SecretKey myRSAPBKey = new SecretKeySpec( keyFactory.generateSecret(pbekSpec).getEncoded(), "RSA");
56        // print the key
57        System.out.println("AES key: " + javax.xml.bind.DatatypeConverter.printHexBinary(myAESPBKey.getEncoded()));
58        
59        //Cipher myAES = null ;
60        // build the key from random key bytes
61        //SecretKeySpec myKey = new SecretKeySpec(keyBytes, "AES");
62        
63        /*String input = System.console().readLine();
64        myAES.init(Cipher.ENCRYPT_MODE, myKey, ivparam);
65        switch(Integer.parseInt(input))
66        {
67            case 1: myAES = Cipher.getInstance("AES/CBC/PKCS5PADDING");
68                break;
69            case 2: break;
70        }*/
71        
72        // instantiate AES object for ECB with no padding
73        Cipher myAES = Cipher.getInstance("AES/CBC/PKCS5Padding");
74        // initialize AES objecy to encrypt mode
75        myAES.init(Cipher.ENCRYPT_MODE, myAESPBKey,ivparam);
76        byte[] plaintext = "password".getBytes();
77        //initialize ciphertext
78        byte[] ciphertext = new byte[16];
79        // update cipher with the plaintext
80        int cLength = myAES.update(plaintext, 0, plaintext.length, ciphertext,0);
81        // process remaining blocks of plaintext
82        cLength += myAES.doFinal(ciphertext, cLength);
83        // print plaintext and ciphertext
84        System.out.println("plaintext: " + javax.xml.bind.DatatypeConverter.printHexBinary(plaintext));
85        System.out.println("ciphertext: " + javax.xml.bind.DatatypeConverter.printHexBinary(ciphertext));
86        // initialize AES for decryption
87        myAES.init(Cipher.DECRYPT_MODE, myAESPBKey,ivparam);
88        // initialize a new array of bytes to place the decryption
89        byte[] dec_plaintext = new byte[16];
90        cLength = myAES.update(ciphertext, 0, ciphertext.length, dec_plaintext,0);
91        // process remaining blocks of ciphertext
92        cLength += myAES.doFinal(dec_plaintext, cLength);
93        // print the new plaintext (hopefully identical to the initial one)
94        System.out.println("decrypted: " + javax.xml.bind.DatatypeConverter.printHexBinary(dec_plaintext));
95        
96        //get a Cipher instance for RSA with PKCS1 padding
97        Cipher myRSA = Cipher.getInstance("RSA/ECB/PKCS1Padding");
98        // get an instance for the Key Generator
99        KeyPairGenerator myRSAKeyGen = KeyPairGenerator.getInstance("RSA");
100        // generate an 1024 bit key
101        myRSAKeyGen.initialize(1024, myPRNG);
102        KeyPair myRSAKeyPair= myRSAKeyGen.generateKeyPair();
103        // store the public and private key individually
104        Key pbKey = myRSAKeyPair.getPublic();
105        Key pvKey = myRSAKeyPair.getPrivate();
106        // init cipher for encryption
107        myRSA.init(Cipher.ENCRYPT_MODE, pbKey, myPRNG);
108        // encrypt, as expected we encrypt a symmetric key with RSA rather than a file or some longer stream which should be encrypted with AES
109        ciphertext = myRSA.doFinal(keyBytes);
110        // init cipher for decryption
111        myRSA.init(Cipher.DECRYPT_MODE, pvKey);
112        // decrypt
113        plaintext = myRSA.doFinal(ciphertext);
114        System.out.println("plaintext: " + javax.xml.bind.DatatypeConverter.printHexBinary(plaintext));
115        System.out.println("ciphertext: " + javax.xml.bind.DatatypeConverter.printHexBinary(ciphertext));
116        System.out.println("keybytes: " + javax.xml.bind.DatatypeConverter.printHexBinary(keyBytes));
117    }
118}