javax.crypto.Cipher Java Examples

public static String decryptMessage(String encrypted_message, String secret_key) throws Exception {

        Log.d("Decrypt", "message: + " + encrypted_message);
        // Creating key and cipher
        SecretKeySpec aesKey = new SecretKeySpec(secret_key.getBytes(), "AES");
        Cipher cipher;

        //AES cipher
        cipher = Cipher.getInstance("AES");

        // decrypting the text
        cipher.init(Cipher.DECRYPT_MODE, aesKey);
        String decrypted;
        byte[] decoded;
        decoded = android.util.Base64.decode(encrypted_message.getBytes(), 0);
        decrypted = new String(cipher.doFinal(decoded));

        //returning decrypted text
        return decrypted;
    }
 

/**
 * Description 根据键值进行加密
 * @param data
 * @param key  加密键byte数组
 * @return
 * @throws Exception
 */
private static byte[] encrypt(byte[] data, byte[] key) throws Exception {
	// 生成一个可信任的随机数源
	SecureRandom sr = new SecureRandom();
	
	// 从原始密钥数据创建DESKeySpec对象
	DESKeySpec dks = new DESKeySpec(key);
	
	// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象
	SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
	SecretKey securekey = keyFactory.generateSecret(dks);
	
	// Cipher对象实际完成加密操作
	Cipher cipher = Cipher.getInstance(DES);
	
	// 用密钥初始化Cipher对象
	cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);
	
	return cipher.doFinal(data);
}
 

/**
 * Generates a random IV and encrypts this plain text with the given key. Then attaches
 * a hashed MAC, which is contained in the CipherTextIvMac class.
 *
 * @param plaintext The text that will be encrypted
 * @param secretKeys The combined AES and HMAC keys with which to encrypt
 * @return a tuple of the IV, ciphertext, mac
 * @throws GeneralSecurityException if AES is not implemented on this system
 */
public static CipherTextIvMac encrypt(byte[] plaintext, SecretKeys secretKeys)
        throws GeneralSecurityException {
    byte[] iv = generateIv();
    Cipher aesCipherForEncryption = Cipher.getInstance(CIPHER_TRANSFORMATION);
    aesCipherForEncryption.init(Cipher.ENCRYPT_MODE, secretKeys.getConfidentialityKey(), new IvParameterSpec(iv));

    /*
     * Now we get back the IV that will actually be used. Some Android
     * versions do funny stuff w/ the IV, so this is to work around bugs:
     */
    iv = aesCipherForEncryption.getIV();
    byte[] byteCipherText = aesCipherForEncryption.doFinal(plaintext);
    byte[] ivCipherConcat = CipherTextIvMac.ivCipherConcat(iv, byteCipherText);

    byte[] integrityMac = generateMac(ivCipherConcat, secretKeys.getIntegrityKey());
    return new CipherTextIvMac(byteCipherText, iv, integrityMac);
}
 

public static byte[] streamEncrypt(String message, SecretKey key,
    MessageDigest digest)
    throws Exception {

    byte[] data;
    Cipher encCipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
    encCipher.init(Cipher.ENCRYPT_MODE, key);
    try (ByteArrayOutputStream bos = new ByteArrayOutputStream();
        DigestOutputStream dos = new DigestOutputStream(bos, digest);
        CipherOutputStream cos = new CipherOutputStream(dos, encCipher)) {
        try (ObjectOutputStream oos = new ObjectOutputStream(cos)) {
            oos.writeObject(message);
        }
        data = bos.toByteArray();
    }

    if (debug) {
        System.out.println(DatatypeConverter.printHexBinary(data));
    }
    return data;
}
 

void writeEntry(@NonNull String entry) throws IOException {
  new SecureRandom().nextBytes(ivBuffer);

  byte[] plaintext = entry.getBytes();
  try {
    cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(secret, "AES"), new IvParameterSpec(ivBuffer));

    int    cipherLength = cipher.getOutputSize(plaintext.length);
    byte[] ciphertext   = ciphertextBuffer.get(cipherLength);
    cipherLength = cipher.doFinal(plaintext, 0, plaintext.length, ciphertext);

    outputStream.write(ivBuffer);
    outputStream.write(Conversions.intToByteArray(cipherLength));
    outputStream.write(ciphertext, 0, cipherLength);

    outputStream.flush();
  } catch (ShortBufferException | InvalidAlgorithmParameterException | InvalidKeyException | BadPaddingException | IllegalBlockSizeException e) {
    throw new AssertionError(e);
  }
}
 

/**
 * Encrypts the given string in a fairly secure way so that it can be
 * {@link #decrypt(String) decrypted} again.
 *
 * @param s string to encrypt
 * @return the encrypted string with a "{AES}" prefix.
 */
private static String encrypt(String s) {
    try {
        SecretKey key = KeyGenerator.getInstance("DES").generateKey();
        Cipher cipher = Cipher.getInstance("DES");
        byte[] keyBytes = key.getEncoded();
        byte[] data = s.getBytes("utf-8");
        ByteArrayOutputStream out = new ByteArrayOutputStream(keyBytes.length + data.length);
        out.write(keyBytes);
        cipher.init(Cipher.ENCRYPT_MODE, key);
        out.write(cipher.update(data));
        out.write(cipher.doFinal());
        StringBuilder ret = new StringBuilder(PREFIX);
        for (byte b: out.toByteArray()) {
            ret.append(Text.hexTable[b>>4 & 0x0f]).append(Text.hexTable[b&0x0f]);
        }
        return ret.toString();
    } catch (Exception e) {
        log.warn("Unable to encrypt string: " + e);
        return null;
    }
}
 

public byte[] encrypt (String passphrase, boolean production) throws ValidationException
{
	try
	{
		byte[] key = SCrypt.generate (passphrase.getBytes ("UTF-8"), BITCOIN_SEED, 16384, 8, 8, 32);
		SecretKeySpec keyspec = new SecretKeySpec (key, "AES");
		Cipher cipher = Cipher.getInstance ("AES/CBC/PKCS5Padding", "BC");
		cipher.init (Cipher.ENCRYPT_MODE, keyspec);
		byte[] iv = cipher.getIV ();
		byte[] c = cipher.doFinal (serialize (production).getBytes ());
		byte[] result = new byte[iv.length + c.length];
		System.arraycopy (iv, 0, result, 0, iv.length);
		System.arraycopy (c, 0, result, iv.length, c.length);
		return result;
	}
	catch ( UnsupportedEncodingException | NoSuchAlgorithmException | NoSuchProviderException | NoSuchPaddingException | InvalidKeyException
			| IllegalBlockSizeException | BadPaddingException e )
	{
		throw new ValidationException (e);
	}
}
 

private void decryptWithWrongAAD() throws Exception {
    System.out.println("decrypt with wrong AAD");

    // initialize it with wrong AAD to get an exception during decryption
    Cipher decryptCipher = createCipher(Cipher.DECRYPT_MODE,
            encryptCipher.getParameters());
    byte[] someAAD = Helper.generateBytes(AAD_SIZE + 1);
    decryptCipher.updateAAD(someAAD);

    // init output stream
    try (ByteArrayOutputStream baOutput = new ByteArrayOutputStream();
            CipherOutputStream ciOutput = new CipherOutputStream(baOutput,
                    decryptCipher);) {
        if (decrypt(ciOutput, baOutput)) {
            throw new RuntimeException(
                    "A decryption has been perfomed successfully in"
                            + " spite of the decrypt Cipher has been"
                            + " initialized with fake AAD");
        }
    }

    System.out.println("Passed");
}
 

public byte[] decrypt(byte[] data) {
    int version = fromSignedByte(data[0]);
    CryptVersion cryptVersion = cryptVersion(version);

    try {
        byte[] random = new byte[cryptVersion.saltLength];
        System.arraycopy(data, 1, random, 0, cryptVersion.saltLength);
        IvParameterSpec iv_spec = new IvParameterSpec(random);

        Cipher cipher = cipher(cryptVersions[version].cipher);
        cipher.init(Cipher.DECRYPT_MODE, cryptVersions[version].key, iv_spec);
        return cipher.doFinal(data, cryptVersion.saltLength + 1, data.length - cryptVersion.saltLength - 1);
    } catch (InvalidKeyException | InvalidAlgorithmParameterException | IllegalBlockSizeException | BadPaddingException e) {
        // wrap checked exception for easy use
        throw new CryptOperationException("JCE exception caught while decrypting with key version " + version, e);
    }
}
 

public static byte[] decrypt(Passphrase passphrase, byte[] encryptedData) throws Exception {
	if (encryptedData.length == 0) {
		return new byte[0];
	}
	byte[] byteHolder1;
	byte[] byteHolder2 = null;
	try {
		List<Cipher> ciphers = cipherList(passphrase.getPassphraseHash(), Cipher.DECRYPT_MODE);
		byteHolder1 = ciphers.get(2).doFinal(encryptedData);
		byteHolder2 = ciphers.get(1).doFinal(byteHolder1);
		byteHolder1 = ciphers.get(0).doFinal(byteHolder2);
		byteHolder2 = unPad4AES(byteHolder1);
	} catch (Exception ex) {
		ex.printStackTrace();
	}
	return byteHolder2;
}
 

static void gcm_suppressUnreadCorrupt() throws Exception {
    Cipher c;
    byte[] read = new byte[200];

    System.out.println("Running supressUnreadCorrupt test");

    // Encrypt 100 bytes with AES/GCM/PKCS5Padding
    byte[] ct = encryptedText("GCM", 100);
    // Corrupt the encrypted message
    ct = corruptGCM(ct);
    // Create stream for decryption
    CipherInputStream in = getStream("GCM", ct);

    try {
        in.close();
        System.out.println("  Pass.");
    } catch (IOException e) {
        System.out.println("  Fail: " + e.getMessage());
        throw new RuntimeException(e.getCause());
    }
}
 

/**
 * @throws RuntimeException in any case of error.
 * @see org.apache.openejb.cipher.PasswordCipher#decrypt(char[])
 */
public String decrypt(final char[] encodedPassword) {
    if (null == encodedPassword || encodedPassword.length == 0) {
        throw new IllegalArgumentException("encodedPassword cannot be null nor empty.");
    }

    try {
        final byte[] cipherText = Base64.decodeBase64(
            String.valueOf(encodedPassword).getBytes());

        // Get a 3DES Cipher object
        final Cipher cipher = Cipher.getInstance(TRANSFORMATION);
        // Set it into decryption mode
        cipher.init(Cipher.DECRYPT_MODE, KEY);

        // Decrypt data
        return new String(cipher.doFinal(cipherText));

    } catch (final Exception e) {
        throw new OpenEJBRuntimeException(e);
    }
}
 

@Override // GemStoneAddition
public void init() throws Exception {
    // generate keys according to the specified algorithms
    // generate publicKey and Private Key using RSA
    KeyPairGenerator KpairGen=KeyPairGenerator.getInstance(getAlgorithm(asymAlgorithm));
    KpairGen.initialize(asymInit, new SecureRandom());
    Kpair=KpairGen.generateKeyPair();

    // generate secret key
    KeyGenerator keyGen=KeyGenerator.getInstance(getAlgorithm(symAlgorithm));
    keyGen.init(symInit);
    desKey=keyGen.generateKey();

    // initialize for rsa, cipher encryption/decryption
    rsa=Cipher.getInstance(asymAlgorithm);
    cipher=Cipher.getInstance(symAlgorithm);


 if(log.isInfoEnabled()) log.info(ExternalStrings.ENCRYPT1_4_BOTH_ASYM_AND_SYM_ALGO_INITIALIZED_WITH_THE_SINGLE_SHARED_KEY);
}
 

public static String encode(String key, String data) {
    if (data == null)
        return null;
    try {
        DESKeySpec dks = new DESKeySpec(key.getBytes());
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
        // key的长度不能够小于8位字节
        Key secretKey = keyFactory.generateSecret(dks);
        Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
        IvParameterSpec iv = new IvParameterSpec("12345678".getBytes());
        AlgorithmParameterSpec paramSpec = iv;
        cipher.init(Cipher.ENCRYPT_MODE, secretKey, paramSpec);
        byte[] bytes = cipher.doFinal(data.getBytes());
        return byte2hex(bytes);
    } catch (Exception e) {
        e.printStackTrace();
        return data;
    }
}
 

private void runGCMWithSameArray(int mode, byte[] array, int txtOffset,
        int length, AlgorithmParameters params) throws Exception {
    // first, generate cipher text at an allocated buffer
    Cipher cipher = createCipher(mode, params);
    cipher.updateAAD(array, 0, AADLength);
    byte[] outputText = cipher.doFinal(array, txtOffset, length);

    // new cipher for encrypt operation
    Cipher anotherCipher = createCipher(mode, params);
    anotherCipher.updateAAD(array, 0, AADLength);

    // next, generate cipher text again at the same buffer of plain text
    int off = anotherCipher.update(array, txtOffset, length,
            array, txtOffset);
    anotherCipher.doFinal(array, txtOffset + off);

    // check if two results are equal or not
    if (!isEqual(array, txtOffset, outputText, 0,
            outputText.length)) {
        throw new RuntimeException(
                "Two results are not equal, mode:" + mode);
    }
}
 

public static String encrypt(String value) {
    try {
        System.out.println(KEY);
        DESKeySpec keySpec = new DESKeySpec(KEY);
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
        SecretKey key = keyFactory.generateSecret(keySpec);

        byte[] clearText = value.getBytes("UTF8");
        // Implement this in a thread safe way, or switch to AES.
        Cipher cipher = Cipher.getInstance("DES");
        cipher.init(Cipher.ENCRYPT_MODE, key);

        String encrypedText = Base64.encodeToString(cipher.doFinal(clearText), Base64.DEFAULT);
        Log.d("Oh snap!", "Encrypted: " + value + " -> " + encrypedText);
        return encrypedText;

    } catch (InvalidKeyException | UnsupportedEncodingException | InvalidKeySpecException | NoSuchAlgorithmException | BadPaddingException | NoSuchPaddingException | IllegalBlockSizeException e) {
        e.printStackTrace();
    }
    return value;
}
 

private void combination_4(List<byte[]> results, int mode, byte[] AAD,
        byte[] plainText, AlgorithmParameters params) throws Exception {
    Cipher ci = createCipher(mode, params);
    ci.updateAAD(AAD);
    byte[] part41 = new byte[ci.getOutputSize(plainText.length)];
    int offset = plainText.length > ARRAY_OFFSET ? ARRAY_OFFSET : 0;
    int len = ci.update(plainText, 0, plainText.length - offset, part41, 0);
    int rest4 = ci.doFinal(plainText, plainText.length - offset, offset,
            part41, len);
    byte[] outputText4 = new byte[len + rest4];
    System.arraycopy(part41, 0, outputText4, 0, outputText4.length);
    results.add(outputText4);
}
 

/**
 * 加密
 *
 * @param algorithm
 * @param data
 * @param key
 * @return
 */
public byte[] encrypt(Algorithm algorithm, byte[] data, String key) {
    try {
        Cipher cipher = Cipher.getInstance(algorithm.toString());
        cipher.init(Cipher.ENCRYPT_MODE, this.toKey(algorithm, key));
        return cipher.doFinal(data);
    } catch (Exception e) {
        log.error("Encrypt setKey is exception.");
        throw new KissoException(e);
    }
}
 

@Override
public Cipher getCipher(int mode){
    try {
        byte[] iv = generateIv();
        Cipher cipher = Cipher.getInstance(CIPHER_TRANSFORMATION);
        cipher.init(mode, mKey.getConfidentialityKey(), new IvParameterSpec(iv));
        return cipher;
    }catch(GeneralSecurityException e){
        e.printStackTrace();
    }
    return null;
}
 

public static Cipher getCipher(String salt, String key, int mode) {
    try {
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
        cipher.init(mode, keyToSpec(salt, key));

        return cipher;
    } catch (GeneralSecurityException e) {
        throw new RuntimeException(e);
    }
}
 

/**
 * Returns the data as an InputStream
 */
public InputStream getInputStream() throws IOException
{
    if (tempFile != null)
    {
        if (encrypt)
        {
            final Cipher cipher;
            try
            {
                cipher = Cipher.getInstance(TRANSFORMATION);
                cipher.init(Cipher.DECRYPT_MODE, symKey, new IvParameterSpec(iv));
            }
            catch (Exception e)
            {
                destroy();

                if (logger.isErrorEnabled())
                {
                    logger.error("Cannot initialize decryption cipher", e);
                }

                throw new IOException("Cannot initialize decryption cipher", e);
            }

            return new BufferedInputStream(new CipherInputStream(new FileInputStream(tempFile), cipher));
        }
        return new BufferedInputStream(new FileInputStream(tempFile));
    }
    else
    {
        return new ByteArrayInputStream(tempStream.getBuffer(), 0, tempStream.getCount());
    }
}
 

public boolean encrypt_AES_key() {
	// get KeySpec
	X509EncodedKeySpec ks = new X509EncodedKeySpec(this.RSA_key);

	try {

		KeyFactory kf = KeyFactory.getInstance("RSA");

		// Get public key from KeySpec
		PublicKey pub = kf.generatePublic(ks);

		// create new AES.key file
		File kfile = new File("AES.key");
		kfile.createNewFile();

		// encrypt AES key with public
		Cipher cipher = Cipher.getInstance("RSA");
		cipher.init(Cipher.ENCRYPT_MODE, pub);

		// encrypted data buffer
		byte[] out = cipher.doFinal(this.PASS);

		// write encrypted data to AES.key file
		Files.write(kfile.toPath(), out);

	} catch (InvalidKeySpecException | IOException | NoSuchPaddingException | InvalidKeyException
			| IllegalBlockSizeException | BadPaddingException | NoSuchAlgorithmException e) {
		e.printStackTrace();
		return false;
	}

	return true;
}
 

/**
 * The method that will encrypt data.
 * 
 * @param secretKey
 * 		The key used to encrypt the data.
 * 
 * @param data
 * 		The data to encrypt.
 * 
 * @return The encrypted data.
 */
public static byte[] encrypt(SecretKey secretKey, byte[] data) {
	try {
		Cipher cipher = Cipher.getInstance(algorithm);
		cipher.init(Cipher.ENCRYPT_MODE, secretKey);
		return cipher.doFinal(data);
	} catch (Exception ex) {

	}

	return null;

}
 

public static String encrypt(String password) throws Exception {
    Key key = getKey();

    Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
    cipher.init(Cipher.ENCRYPT_MODE, key);

    byte[] input = password.getBytes();
    byte[] encrypted = cipher.doFinal(input);

    return new String(Base64.encodeBase64(encrypted));
}
 

StreamReadCipher(Authenticator authenticator,
        ProtocolVersion protocolVersion, String algorithm,
        Key key, AlgorithmParameterSpec params,
        SecureRandom random) throws GeneralSecurityException {
    super(authenticator, protocolVersion);
    this.cipher = JsseJce.getCipher(algorithm);
    cipher.init(Cipher.DECRYPT_MODE, key, params, random);
}
 

public static byte[] desDecrypt(byte[] pwd, byte[] key) throws Exception {
	// 从原始密钥数据创建DESKeySpec对象
	DESKeySpec dks = new DESKeySpec(key);
	// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象
	SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
	SecretKey securekey = keyFactory.generateSecret(dks);
	// Cipher对象实际完成加密操作
	Cipher cipher = Cipher.getInstance(DES);
	// 用密钥初始化Cipher对象
	cipher.init(Cipher.DECRYPT_MODE, securekey, random);
	return cipher.doFinal(pwd);
}
 

private static Cipher getCipherFromPassphrase(String passphrase, byte[] salt, int iterations, int opMode)
    throws GeneralSecurityException
{
  SecretKey key    = getKeyFromPassphrase(passphrase, salt, iterations);
  Cipher    cipher = Cipher.getInstance(key.getAlgorithm());
  cipher.init(opMode, key, new PBEParameterSpec(salt, iterations));

  return cipher;
}
 

public MasterCipher(MasterSecret masterSecret) {
  try {
    this.masterSecret = masterSecret;
    this.encryptingCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
    this.decryptingCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
    this.hmac             = Mac.getInstance("HmacSHA1");
  } catch (NoSuchPaddingException | NoSuchAlgorithmException nspe) {
    throw new AssertionError(nspe);
  }
}
 

final void doTest(BufferType type) throws Exception {
    // init ciphers
    encryptCipher = createCipher(Cipher.ENCRYPT_MODE);
    decryptCipher = createCipher(Cipher.DECRYPT_MODE);

    // init cipher input stream
    ciInput = new CipherInputStream(new ByteArrayInputStream(plaintext),
            encryptCipher);

    runTest(type);
}
 

/**
 * 加密内容
 * 
 * @param tsk
 * @param content
 * @return
 */
public static byte[] encrypt(byte[] tsk, byte[] content) {
	try {
		SecretKeySpec key = new SecretKeySpec(tsk, "AES");
		Cipher cipher = Cipher.getInstance(ALGORITHM);// 创建密码器
		cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
		return cipher.doFinal(content);
	} catch (Exception e) {
		logger.error("aes encrypt error tsk-size={} content-size={}", tsk.length, content.length);
	}
	return null;
}