Encryption_Internal.java
/*
* Copyright 2019 Gregory Graham.
*
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package nz.co.gregs.dbvolution.utility.encryption;
import java.io.IOException;
import java.nio.BufferOverflowException;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.util.Properties;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.ShortBufferException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import nz.co.gregs.dbvolution.exceptions.CannotEncryptInputException;
import nz.co.gregs.dbvolution.exceptions.UnableToDecryptInput;
import nz.co.gregs.dbvolution.utility.StringCheck;
import nz.co.gregs.looper.LoopVariable;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.crypto.cipher.CryptoCipher;
import org.apache.commons.crypto.utils.Utils;
/**
*
* @author gregorygraham
*/
public class Encryption_Internal {
private static final int DEFAULT_BUFFER_SIZE = 1024;
private static final String TRANSFORM = "AES/CBC/PKCS5Padding";
private static final IvParameterSpec IV = new IvParameterSpec(getUTF8Bytes("DBVOLUTION IV SE"));
private static final SecretKeySpec KEY = new SecretKeySpec(getUTF8Bytes("DBVOLUTION KEY S"), "AES");
private static final String ENCYPTED_PREAMPLE = "BASE64_AES:";
public static String encrypt(String inputString) throws CannotEncryptInputException {
Properties properties = new Properties();
//Creates a CryptoCipher instance with the transformation and properties.
int finalBytes;
try (CryptoCipher encipher = Utils.getCipherInstance(TRANSFORM, properties)) {
final byte[] utF8Bytes = getUTF8Bytes(inputString);
ByteBuffer inBuffer;
int bufferSize = DEFAULT_BUFFER_SIZE;
if (utF8Bytes.length > bufferSize) {
bufferSize = utF8Bytes.length;
}
inBuffer = ByteBuffer.allocateDirect(bufferSize);
inBuffer.put(utF8Bytes);
inBuffer.flip(); // ready for the cipher to read it
// Initializes the cipher with ENCRYPT_MODE,key and iv.
encipher.init(Cipher.ENCRYPT_MODE, KEY, IV);
ByteBuffer outBuffer;
int outBufferSize = bufferSize;
int updateBytes;
LoopVariable successfullyCallUpdate = new LoopVariable();
while (successfullyCallUpdate.hasNotHappened()) {
try {
successfullyCallUpdate.attempt();
outBuffer = ByteBuffer.allocateDirect(outBufferSize);
// Continues a multiple-part encryption/decryption operation for byte buffer.
updateBytes = encipher.update(inBuffer, outBuffer);
successfullyCallUpdate.done();
// We should call do final at the end of encryption/decryption.
finalBytes = encipher.doFinal(inBuffer, outBuffer);
outBuffer.flip(); // ready for use as decrypt
byte[] encoded = new byte[updateBytes + finalBytes];
outBuffer.duplicate().get(encoded);
final String base64Encoded = new String(Base64.encodeBase64(encoded), StandardCharsets.UTF_8);
return ENCYPTED_PREAMPLE + base64Encoded;
} catch (javax.crypto.ShortBufferException exp) {
outBufferSize *= 2;
} catch (IllegalBlockSizeException | BadPaddingException | BufferOverflowException ex) {
Logger.getLogger(Encryption_Internal.class.getName()).log(Level.SEVERE, null, ex);
throw new CannotEncryptInputException(ex);
}
}
} catch (IOException | InvalidKeyException | InvalidAlgorithmParameterException ex) {
Logger.getLogger(Encryption_Internal.class.getName()).log(Level.SEVERE, null, ex);
throw new CannotEncryptInputException(ex);
}
throw new CannotEncryptInputException();
}
public static String decrypt(String encodedCipherText) throws UnableToDecryptInput {
if (encodedCipherText != null && !encodedCipherText.isEmpty() && encodedCipherText.startsWith(ENCYPTED_PREAMPLE)) {
String encryptedString = encodedCipherText.replaceFirst(ENCYPTED_PREAMPLE, "");
Properties properties = new Properties();
// decode the base64 encoded input string
byte[] encryptedBytes = Base64.decodeBase64(encryptedString);
int bufferSize = DEFAULT_BUFFER_SIZE;
if (encryptedBytes.length > bufferSize) {
bufferSize = encryptedBytes.length;
}
//Creates a CryptoCipher instance with the transformation and properties.
ByteBuffer inBuffer;
inBuffer = ByteBuffer.allocateDirect(bufferSize);
// push the decoded input into the buffer
inBuffer.put(encryptedBytes);
// reverse the buffer to output mode for processing
inBuffer.flip();
try (CryptoCipher decipher = Utils.getCipherInstance(TRANSFORM, properties)) {
decipher.init(Cipher.DECRYPT_MODE, KEY, IV);
int outBufferSize = bufferSize;
LoopVariable update = new LoopVariable();
LoopVariable doFinal = new LoopVariable();
while (update.isNeeded() || doFinal.isNeeded()) {
ByteBuffer outBuffer = ByteBuffer.allocateDirect(outBufferSize);
try {
decipher.update(inBuffer, outBuffer);
update.done();
decipher.doFinal(inBuffer, outBuffer);
doFinal.done();
outBuffer.flip(); // ready for use
final String decrypted = asString(outBuffer);
return decrypted;
} catch (ShortBufferException ex) {
outBufferSize *= 2;
}
}
} catch (IOException | InvalidKeyException | InvalidAlgorithmParameterException | IllegalBlockSizeException | BadPaddingException | BufferOverflowException ex) {
Logger.getLogger(Encryption_Internal.class
.getName()).log(Level.SEVERE, null, ex);
throw new UnableToDecryptInput(ex);
}
} else {
throw new UnableToDecryptInput("failed to decrypt: "+StringCheck.checkNotNull("\""+encodedCipherText+"\"","NULL"));
}
throw new UnableToDecryptInput("failed to decrypt: "+StringCheck.checkNotNull("\""+encodedCipherText+"\"","NULL"));
}
private static byte[] getUTF8Bytes(String input) {
return input.getBytes(StandardCharsets.UTF_8);
}
private static String asString(ByteBuffer buffer) {
final ByteBuffer copy = buffer.duplicate();
final byte[] bytes = new byte[copy.remaining()];
copy.get(bytes);
return new String(bytes, StandardCharsets.UTF_8);
}
private Encryption_Internal() {
}
}