iGfKSKS3

1package sample;
2
3import javax.crypto.*;
4import java.io.*;
5import java.security.InvalidKeyException;
6import java.security.NoSuchAlgorithmException;
7
8public class CypherUtils {
9
10    private static final String ALGO = "DESede";
11    private SecretKey key;
12
13    public CypherUtils() {
14        key = generateKey();
15    }
16
17    public boolean encrypt(String path, String outputPath) {
18        return doStuff(path, outputPath, key, Cipher.ENCRYPT_MODE);
19    }
20
21    public boolean decrypt(String path, String outputPath) {
22        return doStuff(path, outputPath, key, Cipher.DECRYPT_MODE);
23    }
24
25    private static boolean doStuff(String pathIn, String pathOut, SecretKey key, int mode) {
26
27        FileInputStream in;
28        FileOutputStream out;
29
30        try {
31            in = new FileInputStream(pathIn);
32            out = new FileOutputStream(pathOut);
33
34        } catch (FileNotFoundException e) {
35            return false;
36        }
37
38        Cipher c = getCipher(key, mode);
39        return c != null && writeToFile(in, new CipherOutputStream(out, c));
40    }
41
42    private static boolean writeToFile(InputStream in, OutputStream out) {
43
44        byte[] buffer = new byte[2048];
45        int read_bytes;
46
47        while (true) {
48            try {
49                if ((read_bytes = in.read(buffer)) == -1) break;
50                out.write(buffer, 0, read_bytes);
51            } catch (IOException e) {
52                return false;
53            }
54        }
55
56        try {
57            in.close();
58            out.close();
59        } catch (IOException ignored) {}
60
61        return true;
62    }
63
64    private static SecretKey generateKey() {
65        try {
66            KeyGenerator keygen = KeyGenerator.getInstance(ALGO);
67            return keygen.generateKey();
68        } catch (NoSuchAlgorithmException e) {
69            e.printStackTrace();
70        }
71        return null;
72    }
73
74    private static Cipher getCipher(SecretKey key, int mode) {
75
76        try {
77            Cipher c = Cipher.getInstance(ALGO);
78            c.init(mode, key);
79            return c;
80        } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException e) {
81            return null;
82        }
83    }
84}