RhUMkMVt

1import javax.crypto.*;
2import javax.crypto.spec.IvParameterSpec;
3import javax.crypto.spec.SecretKeySpec;
4import java.net.*;
5import java.io.*;
6import java.security.InvalidAlgorithmParameterException;
7import java.security.InvalidKeyException;
8import java.security.NoSuchAlgorithmException;
9import java.security.SecureRandom;
10
11public class Client {
12    public static void main(String args[]) {
13
14        Socket s = null;
15        int serversocket = 4567;
16        try {
17            s = new Socket("127.0.0.1", serversocket);
18
19            DataInputStream in = new DataInputStream(s.getInputStream());
20            DataOutputStream out = new DataOutputStream(s.getOutputStream());
21
22            while (true){
23                //key
24                byte [] key = {1,2,3,4,1,2,3,4,1,2,3,4,1,2,3,4};
25                SecretKey secretKey = new SecretKeySpec(key, 0, key.length, "AES");
26
27                //nonce
28                byte[] bytesForIV=new byte[16];
29                SecureRandom sr = new SecureRandom();
30                sr.nextBytes(bytesForIV);
31                IvParameterSpec iv = new IvParameterSpec(bytesForIV);
32
33                //sends the bytes in plaintext so that the server can create the same IV
34                out.write(bytesForIV);
35
36                Cipher c = Cipher.getInstance("AES/CTR/PKCS5Padding");
37                c.init(Cipher.ENCRYPT_MODE, secretKey, iv);
38
39                OutputStream ot = out;
40                CipherOutputStream cos = new CipherOutputStream(ot, c);
41                int text;
42                while((text=System.in.read())!=-1){
43                    cos.write((byte)text);
44                    cos.flush();
45                }
46
47            }
48        } catch (UnknownHostException e) {
49            System.out.println("Sock:" + e.getMessage());
50        } catch (EOFException e) {
51            System.out.println("EOF:" + e.getMessage());
52        } catch (IOException e) {
53            System.out.println("IO:" + e.getMessage());
54        } catch (NoSuchPaddingException e) {
55            e.printStackTrace();
56        } catch (NoSuchAlgorithmException e) {
57            e.printStackTrace();
58        } catch (InvalidAlgorithmParameterException e) {
59            e.printStackTrace();
60        } catch (InvalidKeyException e) {
61            e.printStackTrace();
62        } finally {
63            if (s != null)
64                try {
65                    s.close();
66                } catch (IOException e) {
67                    System.out.println("close:" + e.getMessage());
68                }
69        }
70    }
71}