JGHQyWGN

1
2import java.io.UnsupportedEncodingException;
3import java.security.InvalidKeyException;
4
5import java.security.NoSuchAlgorithmException;
6
7
8import javax.crypto.*;
9
10
11import com.sun.mail.util.BASE64DecoderStream;
12
13import com.sun.mail.util.BASE64EncoderStream;
14
15public class des {
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17
18
19
20        private static Cipher ecipher;
21
22        private static Cipher dcipher;
23
24
25
26        private static SecretKey key;
27
28
29
30        public static void main(String[] args) throws InvalidKeyException, NoSuchPaddingException, NoSuchAlgorithmException, UnsupportedEncodingException, IllegalBlockSizeException, BadPaddingException {
31
32
33
34            try {
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36
37
38
39                key = KeyGenerator.getInstance("DES").generateKey();
40
41                ecipher = Cipher.getInstance("DES");
42
43                dcipher = Cipher.getInstance("DES");
44
45                ecipher.init(Cipher.ENCRYPT_MODE, key);
46
47                dcipher.init(Cipher.DECRYPT_MODE, key);
48
49                String encrypted = encrypt("This is a classified message!");
50
51                String decrypted = decrypt(encrypted);
52
53                System.out.println("Decrypted: " + decrypted);
54
55            }
56
57        catch (NoSuchAlgorithmException e) {
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59                System.out.println("No Such Algorithm:" + e.getMessage());
60
61                return;
62
63            }
64
65        catch (NoSuchPaddingException e) {
66
67                System.out.println("No Such Padding:" + e.getMessage());
68
69                return;
70
71            }
72
73        catch (InvalidKeyException e) {
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75                System.out.println("Invalid Key:" + e.getMessage());
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77                return;
78
79            }
80
81
82
83        }
84
85
86
87        public static String encrypt(String str) throws UnsupportedEncodingException, BadPaddingException, IllegalBlockSizeException {
88
89
90
91            try {
92
93
94                byte[] utf8 = str.getBytes("UTF8");
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96                byte[] enc = ecipher.doFinal(utf8);
97
98                enc = BASE64EncoderStream.encode(enc);
99
100                return new String(enc);
101
102            }
103
104  catch (Exception e) {
105
106                e.printStackTrace();
107
108            }
109
110            return null;
111
112        }
113
114
115
116        public static String decrypt(String str) throws UnsupportedEncodingException, BadPaddingException, IllegalBlockSizeException {
117
118            try {
119
120                byte[] dec = BASE64DecoderStream.decode(str.getBytes());
121
122                byte[] utf8 = dcipher.doFinal(dec);
123
124                return new String(utf8, "UTF8");
125
126            }
127
128
129
130  catch (Exception e) {
131
132                e.printStackTrace();
133
134            }
135
136            return null;
137
138        }
139
140    }
141
142}