mN8Mcbk3

1import java.io.InputStream; 
2import java.io.OutputStream; 
3import java.io.FileInputStream; 
4import java.io.FileOutputStream; 
5import java.io.ObjectOutputStream; 
6import java.io.ObjectInputStream; 
7
8import javax.crypto.Cipher; 
9import javax.crypto.SecretKey; 
10import javax.crypto.spec.IvParameterSpec; 
11import javax.crypto.CipherInputStream; 
12import javax.crypto.CipherOutputStream; 
13import javax.crypto.KeyGenerator; 
14
15import java.security.spec.AlgorithmParameterSpec; 
16
17public class AESEncrypter 
18{ 
19Cipher ecipher; 
20Cipher dcipher; 
21
22public AESEncrypter(SecretKey key) 
23{ 
24// Create an 8-byte initialization vector 
25byte[] iv = new byte[] 
26{ 
270x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f 
28}; 
29
30AlgorithmParameterSpec paramSpec = new IvParameterSpec(iv); 
31try 
32{ 
33ecipher = Cipher.getInstance("AES/CBC/PKCS5Padding"); 
34dcipher = Cipher.getInstance("AES/CBC/PKCS5Padding"); 
35
36// CBC requires an initialization vector 
37ecipher.init(Cipher.ENCRYPT_MODE, key, paramSpec); 
38dcipher.init(Cipher.DECRYPT_MODE, key, paramSpec); 
39} 
40catch (Exception e) 
41{ 
42e.printStackTrace(); 
43} 
44} 
45
46// Buffer used to transport the bytes from one stream to another 
47byte[] buf = new byte[1024]; 
48
49public void encrypt(InputStream in, OutputStream out) 
50{ 
51try 
52{ 
53// Bytes written to out will be encrypted 
54out = new CipherOutputStream(out, ecipher); 
55
56// Read in the cleartext bytes and write to out to encrypt 
57int numRead = 0; 
58while ((numRead = in.read(buf)) >= 0) 
59{ 
60out.write(buf, 0, numRead); 
61} 
62out.close(); 
63} 
64catch (java.io.IOException e) 
65{ 
66} 
67} 
68
69public void decrypt(InputStream in, OutputStream out) 
70{ 
71try 
72{ 
73// Bytes read from in will be decrypted 
74in = new CipherInputStream(in, dcipher); 
75
76// Read in the decrypted bytes and write the cleartext to out 
77int numRead = 0; 
78while ((numRead = in.read(buf)) >= 0) 
79{ 
80out.write(buf, 0, numRead); 
81} 
82out.close(); 
83} 
84catch (java.io.IOException e) 
85{ 
86} 
87} 
88
89public static void main(String args[]) 
90{ 
91try 
92{ 
93// Generate a temporary key. In practice, you would save this key. 
94// See also e464 Encrypting with DES Using a Pass Phrase. 
95
96KeyGenerator kgen = KeyGenerator.getInstance("AES"); 
97kgen.init(128); 
98SecretKey key = kgen.generateKey(); 
99
100// Create encrypter/decrypter class 
101AESEncrypter encrypter = new AESEncrypter(key); 
102
103// Encrypt 
104encrypter.encrypt(new FileInputStream("E:\\keeper.txt"),new FileOutputStream("E:\\Encrypted.txt")); 
105// Decrypt 
106encrypter.decrypt(new FileInputStream("E:\\keeper.txt"),new FileOutputStream("E:\\Decrypted.txt")); 
107} 
108catch (Exception e) 
109{ 
110e.printStackTrace(); 
111} 
112} 
113}