package sample.crypto;import java.io.File;
import java.io.IOException;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ByteArrayOutputStream;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.KeyGenerator;
import javax.crypto.BadPaddingException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.spec.SecretKeySpec;public final class SymmetryCryptographerSample
extends Object
{
public static void main(String[] args)
throws IOException,
BadPaddingException,
InvalidKeyException,
ClassNotFoundException,
NoSuchPaddingException,
NoSuchAlgorithmException,
IllegalBlockSizeException
{
KeyGenerator keyGenerator = null;
String keyFileName = null;
String encodingFileName = null;
String resultFileName = null;
String sourceFileName = null;
SecretKey key = null;
SecretKeySpec keySpec = null;
byte[] encoding = null;
Cipher cipher = null;
byte[] source = null;
byte[] result = null; for (int i = 0; i<CRYPTOGRAPHERS.length; i++)
{
keyFileName =
KEY_FILE_NAME+CRYPTOGRAPHERS[i]+".txt";
encodingFileName =
ENCODING_FILE_NAME+CRYPTOGRAPHERS[i]+".txt";
keyGenerator = KeyGenerator.getInstance(
CRYPTOGRAPHERS[i]);
saveKey(keyGenerator, keyFileName);
key = loadKey(keyFileName);
encoding = key.getEncoded();
saveKeyEncoding(key, encodingFileName); resultFileName =
RESULT_FILE_NAME+CRYPTOGRAPHERS[i]+".txt";
cipher = Cipher.getInstance(CRYPTOGRAPHERS[i]);
cipher.init(Cipher.ENCRYPT_MODE, key);
source = loadSource(getSourceFile());
result = cipher.doFinal(source);
saveResult(result, resultFileName); sourceFileName =
SOURCE_FILE_NAME+CRYPTOGRAPHERS[i]+".txt";
encoding = loadKeyEncoding(encodingFileName);
keySpec =
new SecretKeySpec(encoding, CRYPTOGRAPHERS[i]);
cipher = Cipher.getInstance(CRYPTOGRAPHERS[i]);
cipher.init(Cipher.DECRYPT_MODE, key);
result = loadResult(resultFileName);
source = cipher.doFinal(result);
saveSource(source, sourceFileName);
}
} private static void saveKey(
KeyGenerator keyGenerator,
String keyFileName)
throws IOException
{
FileOutputStream outFile =
new FileOutputStream(keyFileName);
ObjectOutputStream outObject =
new ObjectOutputStream(outFile); SecretKey key = keyGenerator.generateKey();
outObject.writeObject(key); outObject.close();
outFile.close();
} private static SecretKey loadKey(
String keyFileName)
throws IOException,
ClassNotFoundException
{
FileInputStream inFile =
new FileInputStream(keyFileName);
ObjectInputStream inObject =
new ObjectInputStream(inFile);
Object object = inObject.readObject();
return (SecretKey)object;
} private static void saveKeyEncoding(
SecretKey key,
String encodingFileName)
throws IOException
{
FileOutputStream outFile =
new FileOutputStream(encodingFileName);
ObjectOutputStream outObject =
new ObjectOutputStream(outFile); outObject.write(key.getEncoded()); outObject.close();
outFile.close();
} private static byte[] loadKeyEncoding(
String encodingFileName)
throws IOException,
ClassNotFoundException
{
FileInputStream inFile =
new FileInputStream(encodingFileName);
ByteArrayOutputStream outByteArray =
new ByteArrayOutputStream();
int i = -1;
while ((i = inFile.read())!=-1)
outByteArray.write((byte)i);
return outByteArray.toByteArray();
} private static void saveSource(
byte[] source,
String fileName)
throws IOException
{
FileOutputStream outFile =
new FileOutputStream(fileName);
outFile.write(source);
outFile.close();
} private static byte[] loadSource(File file)
throws IOException
{
FileInputStream inFile = new FileInputStream(file);
ByteArrayOutputStream outByteArray =
new ByteArrayOutputStream();
int i = -1;
while ((i = inFile.read())!=-1)
outByteArray.write((byte)i);
return outByteArray.toByteArray();
} private static void saveResult(
byte[] result,
String fileName)
throws IOException
{
FileOutputStream outFile =
new FileOutputStream(fileName);
outFile.write(result);
outFile.close();
} private static byte[] loadResult(
String fileName)
throws IOException
{
FileInputStream inFile = new FileInputStream(fileName);
ByteArrayOutputStream outByteArray =
new ByteArrayOutputStream();
int i = -1;
while ((i = inFile.read())!=-1)
outByteArray.write((byte)i);
return outByteArray.toByteArray();
} private static String[] getCryptographers()
{
return CRYPTOGRAPHERS;
} private static File getSourceFile()
throws IOException
{
return new File("Source.txt");
} private static final String[] CRYPTOGRAPHERS =
new String[]
{
"Blowfish",
"DES",
"DESede",
//"HmacMD5",
//"HmacSHA1",
"AES"
}; private static final String KEY_FILE_NAME =
"SymmetryKey_"; private static final String ENCODING_FILE_NAME =
"SymmetryEncoding_"; private static final String RESULT_FILE_NAME =
"SymmetryResult_"; private static final String SOURCE_FILE_NAME =
"SymmetrySource_"; private SymmetryCryptographerSample()
{
super();
}
}