c9eqLVdE

1public byte[] autenticacao(byte[] input, SecretKey secret) throws DataLengthException, InvalidCipherTextException {
2	CBCBlockCipher cbcBlockCipher = new CBCBlockCipher(new AESEngine());
3	//SecureRandom random = new SecureRandom();
4	BlockCipherPadding bcp = new PKCS7Padding();
5	PaddedBufferedBlockCipher pbbc = new PaddedBufferedBlockCipher(cbcBlockCipher, bcp);
6
7	int blockSize = cbcBlockCipher.getBlockSize();
8	int inputOffset = 0;
9	int inputLength = input.length;
10	int outputOffset = 0;
11
12	byte[] iv = new byte[blockSize];
13	outputOffset += blockSize;
14
15	pbbc.init(true, new ParametersWithIV(new KeyParameter(secret.getEncoded()), iv));
16	byte[] output = new byte[pbbc.getOutputSize(inputLength) + outputOffset];
17
18	System.arraycopy(iv, 0, output, 0, blockSize);
19
20	int outputLength = outputOffset + pbbc.processBytes(input, inputOffset, inputLength, output, outputOffset);
21
22	outputLength += pbbc.doFinal(output, outputLength);
23
24	//Pego apenas o último bloco
25	byte[] out = new byte[blockSize];
26	System.arraycopy(output, outputLength - blockSize, out, 0, blockSize);
27
28	return out;
29}
30
31private byte[] process(byte[] input, boolean encrypt, SecretKey secret) throws DataLengthException, IllegalStateException, InvalidCipherTextException {
32	CBCBlockCipher cbcBlockCipher = new CBCBlockCipher(new AESEngine());
33	BlockCipherPadding bcp = new PKCS7Padding();
34	PaddedBufferedBlockCipher pbbc = new PaddedBufferedBlockCipher(cbcBlockCipher, bcp);
35
36	int blockSize = cbcBlockCipher.getBlockSize();
37	int inputOffset = 0;
38	int inputLength = input.length;
39	int outputOffset = 0;
40
41	byte[] iv = new byte[blockSize];
42	if (encrypt) {
43		//random.nextBytes(iv);
44		outputOffset += blockSize;
45	} else {
46		System.arraycopy(input, 0, iv, 0, blockSize);
47		inputOffset += blockSize;
48		inputLength -= blockSize;
49	}
50
51	pbbc.init(encrypt, new ParametersWithIV(new KeyParameter(secret.getEncoded()), iv));
52	byte[] output = new byte[pbbc.getOutputSize(inputLength) + outputOffset];
53
54	if (encrypt) {
55		System.arraycopy(iv, 0, output, 0, blockSize);
56	}
57
58	int outputLength = outputOffset + pbbc.processBytes(input, inputOffset, inputLength, output, outputOffset);
59
60	outputLength += pbbc.doFinal(output, outputLength);
61
62	byte[] out = new byte[outputLength];
63	System.arraycopy(output, 0, out, 0, outputLength);
64
65	return out;
66}