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package ase;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.AlgorithmParameters;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.InvalidParameterSpecException;
import java.security.spec.KeySpec;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
public class AES128_File {
public static String byteToHex(byte[] raw) {
String HEXES = "0123456789ABCDEF";
if (raw == null) {
return null;
}
final StringBuilder hex = new StringBuilder(2 * raw.length);
for (final byte b : raw) {
hex.append(HEXES.charAt((b & 0xF0) >> 4)).append(HEXES.charAt((b & 0x0F)));
}
return hex.toString();
}
public static byte[] hexToByte(String hexString) {
int len = hexString.length();
byte[] ba = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
ba[i / 2] = (byte) ((Character.digit(hexString.charAt(i), 16) << 4) + Character.digit(hexString.charAt(i + 1), 16));
}
return ba;
}
/**
* @param msg
*/
private void cryptMessage(String msg) {
System.out.println("** Crypt ** " + msg);
}
/**
* @param input
* - the cleartext file to be encrypted
* @param output
* - the encrypted data file
* @throws IOException
* @throws IllegalBlockSizeException
* @throws BadPaddingException
*/
public void WriteEncryptedFile(String cryptKey,InputStream inputStream, OutputStream outputStream) throws IOException, IllegalBlockSizeException, BadPaddingException {
try {
int SALT_LEN = 8;
byte[] mInitVec = null;
byte[] mSalt = new byte[SALT_LEN];
Cipher mEcipher = null;
int KEYLEN_BITS = 128; // see notes below where this is used.
int ITERATIONS = 65536;
int MAX_FILE_BUF = 2048;
long totalread = 0;
int nread = 0;
byte[] inbuf = new byte[MAX_FILE_BUF];
SecretKeyFactory factory = null;
SecretKey tmp = null;
mSalt = new byte[SALT_LEN];
SecureRandom rnd = new SecureRandom();
rnd.nextBytes(mSalt);
cryptMessage("generated salt :" + byteToHex(mSalt));
factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
KeySpec spec = new PBEKeySpec(cryptKey.toCharArray(), mSalt, ITERATIONS, KEYLEN_BITS);
tmp = factory.generateSecret(spec);
SecretKey secret = new SecretKeySpec(tmp.getEncoded(), "AES");
mEcipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
mEcipher.init(Cipher.ENCRYPT_MODE, secret);
AlgorithmParameters params = mEcipher.getParameters();
mInitVec = params.getParameterSpec(IvParameterSpec.class).getIV();
System.out.println("mInitVec : " + mInitVec);
cryptMessage("mInitVec is :" + byteToHex(mInitVec));
outputStream.write(mSalt);
outputStream.write(mInitVec);
while ((nread = inputStream.read(inbuf)) > 0) {
cryptMessage("read " + nread + " bytes");
totalread += nread;
byte[] trimbuf = new byte[nread];
for (int i = 0; i < nread; i++) {
trimbuf[i] = inbuf[i];
}
byte[] tmpBuf = mEcipher.update(trimbuf);
if (tmpBuf != null) {
outputStream.write(tmpBuf);
}
}
byte[] finalbuf = mEcipher.doFinal();
if (finalbuf != null) {
outputStream.write(finalbuf);
}
outputStream.flush();
inputStream.close();
outputStream.close();
outputStream.close();
cryptMessage("wrote " + totalread + " encrypted bytes");
System.out.println("파일 암호화 성공");
} catch (InvalidKeyException ex) {
Logger.getLogger(AES128_File.class.getName()).log(Level.SEVERE, null, ex);
} catch (InvalidParameterSpecException ex) {
Logger.getLogger(AES128_File.class.getName()).log(Level.SEVERE, null, ex);
} catch (NoSuchAlgorithmException ex) {
Logger.getLogger(AES128_File.class.getName()).log(Level.SEVERE, null, ex);
} catch (NoSuchPaddingException ex) {
Logger.getLogger(AES128_File.class.getName()).log(Level.SEVERE, null, ex);
} catch (InvalidKeySpecException ex) {
Logger.getLogger(AES128_File.class.getName()).log(Level.SEVERE, null, ex);
}
}
/**
* Read from the encrypted file (input) and turn the cipher back into
* cleartext. Write the cleartext buffer back out to disk as (output) File.
*
* I left CipherInputStream in here as a test to see if I could mix it with
* the update() and final() methods of encrypting and still have a correctly
* decrypted file in the end. Seems to work so left it in.
*
* @param input
* - File object representing encrypted data on disk
* @param output
* - File object of cleartext data to write out after decrypting
* @throws IllegalBlockSizeException
* @throws BadPaddingException
* @throws IOException
*/
public void ReadEncryptedFile(String cryptKey,InputStream inputStream, OutputStream outputStream) throws IllegalBlockSizeException, BadPaddingException, IOException {
try {
int SALT_LEN = 8;
byte[] mInitVec = null;
byte[] mSalt = new byte[SALT_LEN];
Cipher mDecipher = null;
int KEYLEN_BITS = 128; // see notes below where this is used.
int ITERATIONS = 65536;
int MAX_FILE_BUF = 2048;
CipherInputStream cin;
long totalread = 0;
int nread = 0;
byte[] inbuf = new byte[MAX_FILE_BUF];
SecretKeyFactory factory = null;
SecretKey tmp = null;
// SecretKey secret = null;
// Read the Salt
inputStream.read(mSalt);
cryptMessage("generated salt :" + byteToHex(mSalt));
factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
KeySpec spec = new PBEKeySpec(cryptKey.toCharArray(), mSalt, ITERATIONS, KEYLEN_BITS);
tmp = factory.generateSecret(spec);
SecretKey secret = new SecretKeySpec(tmp.getEncoded(), "AES");
mDecipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
mDecipher.init(Cipher.ENCRYPT_MODE, secret);
AlgorithmParameters params = mDecipher.getParameters();
mInitVec = params.getParameterSpec(IvParameterSpec.class).getIV();
inputStream.read(mInitVec);
cryptMessage("mInitVec is :" + byteToHex(mInitVec));
mDecipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(mInitVec));
cin = new CipherInputStream(inputStream, mDecipher);
System.out.println("inbuf.length : " + inbuf.length);
while ((nread = cin.read(inbuf)) > 0) {
// Db("read " + nread + " bytes");
totalread += nread;
byte[] trimbuf = new byte[nread];
for (int i = 0; i < nread; i++) {
trimbuf[i] = inbuf[i];
}
// write out the size-adjusted buffer
outputStream.write(trimbuf);
}
outputStream.flush();
cin.close();
inputStream.close();
outputStream.close();
cryptMessage("wrote " + totalread + " encrypted bytes");
} catch (Exception ex) {
ex.getStackTrace();
Logger.getLogger(AES128_File.class.getName()).log(Level.SEVERE, null, ex);
}
}
/**
* adding main() for usage demonstration. With member vars, some of the
* locals would not be needed
*/
public static void main(String[] args) {
// create the input.txt file in the current directory before continuing
File input = new File("C:\\Test\\test.txt");
File eoutput = new File("C:\\Test\\test.aes");
File doutput = new File("C:\\Test\\decrypted1.txt");
String iv = null;
String salt = null;
AES128_File aesFile = new AES128_File();
String cryptKey = "1q2w3e";
/*
* write out encrypted file
*/
try {
aesFile.WriteEncryptedFile(cryptKey,new FileInputStream(input), new FileOutputStream(eoutput));
System.out.printf("File encrypted to " + eoutput.getName() + "\niv:" + iv + "\nsalt:" + salt + "\n\n");
} catch (IllegalBlockSizeException | BadPaddingException | IOException e) {
e.printStackTrace();
}
/*
* decrypt file
*/
/*
* write out decrypted file
*/
try {
aesFile.ReadEncryptedFile(cryptKey,new FileInputStream(eoutput), new FileOutputStream(doutput));
System.out.println("decryption finished to " + doutput.getName());
} catch (IllegalBlockSizeException | BadPaddingException | IOException e) {
e.printStackTrace();
}
}
}
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