public void inicializarSeguridad() {
// Generar la llave
try {
KeyGenerator keygen = KeyGenerator.getInstance("DES");
desKey = keygen.generateKey();
// Iniciar un objeto para la encr / desencr
desCipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
} catch (Exception e) {
}
}
public static void main(String[] args) throws Exception {
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
// get user inputted key
byte[] userkey = null;
do {
System.out.println("Please enter a 8 character string to generate a Secret Key");
userkey = (in.readLine()).getBytes();
} while (userkey.length != 8);
// create Key Generator instance and generate a secret key
KeyGenerator kgen = KeyGenerator.getInstance("DES");
SecretKey skey = kgen.generateKey();
byte[] key = userkey;
// Create a Secret Key based on characters entered by the user
SecretKeySpec skeyspec = new SecretKeySpec(key, "DES");
// Create a cipher to encrypt with
Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, skeyspec);
// Get message
System.out.println("Please enter a string to encrypt");
byte[] userstring = null;
userstring = (in.readLine()).getBytes();
// Encrypt message with cipher
byte[] encrypted = cipher.doFinal(userstring);
String enc_string = new String(encrypted);
System.out.println("The String is encrypted as " + enc_string);
byte[] userdecrypt = null;
byte[] decrypted = null;
// Get user decrypt key
do {
System.out.println("Please enter the 8 character key to decrypt the message");
userdecrypt = (in.readLine()).getBytes();
} while (userdecrypt.length != 8);
// Reinitialize Secret Key and Cipher
key = userdecrypt;
SecretKeySpec decryptkey = new SecretKeySpec(key, "DES");
cipher.init(Cipher.DECRYPT_MODE, decryptkey);
// Decrypt message
decrypted = cipher.doFinal(encrypted);
if ((new String(decrypted)).equals(new String(userstring)))
System.out.println("\nMessage decrypted as: " + (new String(decrypted)));
else System.out.println("\nMessage was not decrypted");
}
public Encrypter() {
try {
SecretKey key = KeyGenerator.getInstance("DES").generateKey();
ecipher = Cipher.getInstance("DES");
dcipher = Cipher.getInstance("DES");
ecipher.init(Cipher.ENCRYPT_MODE, key);
dcipher.init(Cipher.DECRYPT_MODE, key);
} catch (javax.crypto.NoSuchPaddingException e) {
} catch (java.security.NoSuchAlgorithmException e) {
} catch (java.security.InvalidKeyException e) {
}
}
public static void main(String[] args) {
try {
if (args[0].equals("-genkey")) {
KeyPairGenerator pairgen = KeyPairGenerator.getInstance("RSA");
SecureRandom random = new SecureRandom();
pairgen.initialize(KEYSIZE, random);
KeyPair keyPair = pairgen.generateKeyPair();
ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(args[1]));
out.writeObject(keyPair.getPublic());
out.close();
out = new ObjectOutputStream(new FileOutputStream(args[2]));
out.writeObject(keyPair.getPrivate());
out.close();
} else if (args[0].equals("-encrypt")) {
KeyGenerator keygen = KeyGenerator.getInstance("AES");
SecureRandom random = new SecureRandom();
keygen.init(random);
SecretKey key = keygen.generateKey();
// wrap with RSA public key
ObjectInputStream keyIn = new ObjectInputStream(new FileInputStream(args[3]));
Key publicKey = (Key) keyIn.readObject();
keyIn.close();
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.WRAP_MODE, publicKey);
byte[] wrappedKey = cipher.wrap(key);
DataOutputStream out = new DataOutputStream(new FileOutputStream(args[2]));
out.writeInt(wrappedKey.length);
out.write(wrappedKey);
InputStream in = new FileInputStream(args[1]);
cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, key);
crypt(in, out, cipher);
in.close();
out.close();
} else {
DataInputStream in = new DataInputStream(new FileInputStream(args[1]));
int length = in.readInt();
byte[] wrappedKey = new byte[length];
in.read(wrappedKey, 0, length);
// unwrap with RSA private key
ObjectInputStream keyIn = new ObjectInputStream(new FileInputStream(args[3]));
Key privateKey = (Key) keyIn.readObject();
keyIn.close();
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.UNWRAP_MODE, privateKey);
Key key = cipher.unwrap(wrappedKey, "AES", Cipher.SECRET_KEY);
OutputStream out = new FileOutputStream(args[2]);
cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, key);
crypt(in, out, cipher);
in.close();
out.close();
}
} catch (IOException e) {
e.printStackTrace();
} catch (GeneralSecurityException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
/**
* Constructs a new QuickChipher with the given transformation and algorithm.
*
* @param transformation the transformation to be used to create the Cipher for this QuickCipher.
* @param algorithm the algorithm to be used to create the SecretKey for this QuickCipher.
* @throws NoSuchAlgorithmException if transformation is null, empty, in an invalid format, or if
* no Provider supports a CipherSpi implementation for the specified algorithm or if no
* Provider supports a KeyGeneratorSpi implementation for the specified algorithm.
* @throws NoSuchPaddingException if transformation contains a padding scheme that is not
* available.
*/
public QuickCipher(String transformation, String algorithm)
throws NoSuchAlgorithmException, NoSuchPaddingException {
this.algorithm = algorithm;
cipher = Cipher.getInstance(transformation);
key = KeyGenerator.getInstance(this.algorithm).generateKey();
}