isV5Fjqb

1protected void EncryptAndroid()
2{
3byte[] data = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
4        '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
5        '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',                
6        };
7byte[] header = {'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd',
8        'a', 'b', 'c', 'd',};
9byte[] updatedHeader = {'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D',
10        'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D'};
11
12try {
13    SecretKey secret = generateKeyAndroid();
14
15    Cipher cipher = Cipher.getInstance("AES/CTR/NoPadding");
16    cipher.init(Cipher.ENCRYPT_MODE, secret);
17
18    AlgorithmParameters params = cipher.getParameters();
19    byte[] iv = params.getParameterSpec(IvParameterSpec.class).getIV();
20
21    FileOutputStream os = new FileOutputStream(sdCard.getAbsolutePath() + "/Notes/sample.encrypted");
22    CipherOutputStream cos = new CipherOutputStream(os, cipher);
23
24    int offset = 0;
25    cos.write(header, offset, 10);
26    cos.write(data, offset, 40);
27
28    FileOutputStream ivStream = new FileOutputStream(sdCard.getAbsolutePath() + "/Notes/iv.dat");
29    if (ivStream != null) {
30        Log.d("Encryption", "Writing iv data to output file");
31        ivStream.write(iv);
32    }
33    ivStream.close();
34    cos.close();
35
36    //Create new instance of cipher
37    cipher = Cipher.getInstance("AES/CTR/NoPadding");
38    cipher.init(Cipher.ENCRYPT_MODE, secret);
39
40    AlgorithmParameters params1 = cipher.getParameters();
41    byte[] iv1 = params1.getParameterSpec(IvParameterSpec.class).getIV();
42
43    //Re open the file to Update the header at starting of the file.
44    FileOutputStream os1 = new FileOutputStream(sdCard.getAbsolutePath() + "/Notes/sample.encrypted");
45    CipherOutputStream cos1 = new CipherOutputStream(os1, cipher);
46    cos1.write(updatedHeader, offset, 10);
47    cos1.close();
48
49    FileOutputStream ivStream1 = new FileOutputStream(sdCard.getAbsolutePath() + "/Notes/iv1.dat");
50    if (ivStream1 != null) {
51        Log.d("Encryption", "Writing iv data to output file");
52        ivStream1.write(iv1);
53    }
54}catch (Exception e) {
55    e.printStackTrace();
56}
57}
58
59protected void DecryptAndroid() {
60   byte[] hBytes = new byte[10];
61   byte[] dBytes = new byte[100];
62
63try {
64    Log.d("Decryption", "Reading iv data ");
65    File f1 = new File(sdCard.getAbsolutePath() + "/Notes/iv.dat");
66    byte[] newivtext = new byte[(int) f1.length()];
67    FileInputStream readivStream = new FileInputStream(sdCard.getAbsolutePath() + "/Notes/iv.dat");
68    if (readivStream != null) {
69        readivStream.read(newivtext);
70    }
71
72    File f2 = new File(sdCard.getAbsolutePath() + "/Notes/iv1.dat");
73    byte[] newivtext1 = new byte[(int) f2.length()];
74    FileInputStream readivStream1 = new FileInputStream(sdCard.getAbsolutePath() + "/Notes/iv1.dat");
75    if (readivStream1 != null) {
76        readivStream1.read(newivtext1);
77    }
78
79    // The key can also be obtained from the Android Keystore any time as follows:
80    KeyStore keyStore = KeyStore.getInstance("AndroidKeyStore");
81    keyStore.load(null);
82    SecretKey dsecret = (SecretKey) keyStore.getKey("key2", null);
83
84    // Initialize dcipher
85    Cipher dcipher = Cipher.getInstance("AES/CTR/NoPadding");
86    dcipher.init(Cipher.DECRYPT_MODE, dsecret,new IvParameterSpec(newivtext1));
87
88    FileInputStream inputStream = new FileInputStream(sdCard.getAbsolutePath() + "/Notes/sample.encrypted");
89    FileOutputStream os = new FileOutputStream(sdCard.getAbsolutePath() + "/Notes/sample.decrypted");
90
91    //decrypt header
92    int b = inputStream.read(hBytes);
93    byte[] dB = new byte[10];
94    dB = dcipher.doFinal(hBytes);
95    os.write(dB, 0, b);
96
97    // Re-Initialize dcipher
98    dcipher = Cipher.getInstance("AES/CTR/NoPadding");
99    dcipher.init(Cipher.DECRYPT_MODE, dsecret,new IvParameterSpec(newivtext));
100    FileInputStream inputStream1 = new FileInputStream(sdCard.getAbsolutePath() + "/Notes/sample.encrypted");
101    inputStream1.skip(10);
102    CipherInputStream cis = new CipherInputStream(inputStream1, dcipher);
103    b = cis.read(dBytes);
104    while (b != -1) {
105        Log.d("Decryption", "Bytes decrypted" + b);
106        os.write(dBytes, 0, b);
107    }
108    cis.close();
109    os.close();
110
111} catch (Exception e) {
112    e.printStackTrace();
113}
114}