public static void main(String[] args) {
if (args.length == 1) {
if (args[0].equals("-genkey")) {
try {
CipherUtils.generateKey();
} catch (KeyStoreException
| CertificateException
| NoSuchAlgorithmException
| IOException e) {
e.printStackTrace();
}
System.exit(0);
} else {
System.exit(-1);
}
}
try {
Socket s = new Socket("localhost", Servidor.PORT);
ObjectOutputStream oos = new ObjectOutputStream(s.getOutputStream());
ObjectInputStream ois = new ObjectInputStream(s.getInputStream());
CipherUtils cipherUtils = new CipherUtils(ois, oos);
String test;
BufferedReader stdIn = new BufferedReader(new InputStreamReader(System.in));
while ((test = stdIn.readLine()) != null) {
cipherUtils.encrypt(test);
}
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void run() {
ObjectInputStream ois = null;
ObjectOutputStream oos = null;
try {
oos = new ObjectOutputStream(mSocket.getOutputStream());
ois = new ObjectInputStream(mSocket.getInputStream());
// Enviar o nosso g^Y
oos.writeUTF(mPrivateKey.toString());
oos.flush();
// Receber o g^X da Alice
BigInteger gX = new BigInteger(ois.readUTF());
// Calcular a chave
mKey = mGpowModP.modPow(gX, mPrime);
CipherUtils cipherUtils = new CipherUtils(ois, oos, mKey);
String test;
BufferedReader stdIn = new BufferedReader(new InputStreamReader(System.in));
while ((test = stdIn.readLine()) != null) {
cipherUtils.encrypt(test);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (ois != null) {
try {
ois.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (oos != null) {
try {
oos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/*
* Initial IV client to server: HASH (K || H || "A" || session_id) Initial
* IV server to client: HASH (K || H || "B" || session_id) Encryption key
* client to server: HASH (K || H || "C" || session_id) Encryption key
* server to client: HASH (K || H || "D" || session_id) Integrity key client
* to server: HASH (K || H || "E" || session_id) Integrity key server to
* client: HASH (K || H || "F" || session_id)
*/
public void init(
String encryptionAlgorithm,
String cipherAlgorithm,
int keyLength,
String macAlgorithm,
byte[] K,
byte[] H,
byte[] sessionId)
throws GeneralSecurityException {
MessageDigest sha = MessageDigest.getInstance("SHA-1");
sha.reset();
sha.update(
new SshPacketBuilder().writeMpInt(K).append(H).writeByte('A').append(sessionId).finish());
byte[] iv = sha.digest();
sha.reset();
sha.update(
new SshPacketBuilder().writeMpInt(K).append(H).writeByte('C').append(sessionId).finish());
byte[] cipherKey = sha.digest();
try {
cipher = Cipher.getInstance(encryptionAlgorithm + "/" + cipherAlgorithm + "/NoPadding");
iv = CipherUtils.expandKey(K, H, iv, sha, cipher.getBlockSize());
cipherKey = CipherUtils.expandKey(K, H, cipherKey, sha, keyLength);
iv = CipherUtils.shrinkKey(iv, cipher.getBlockSize());
cipherKey = CipherUtils.shrinkKey(cipherKey, keyLength);
cipher.init(
Cipher.ENCRYPT_MODE,
new SecretKeySpec(cipherKey, encryptionAlgorithm),
new IvParameterSpec(iv));
sha.reset();
sha.update(
new SshPacketBuilder().writeMpInt(K).append(H).writeByte('E').append(sessionId).finish());
byte[] macKey = sha.digest();
mac = Mac.getInstance(macAlgorithm);
macKey = CipherUtils.expandKey(K, H, macKey, sha, mac.getMacLength());
macKey = CipherUtils.shrinkKey(macKey, mac.getMacLength());
mac.init(new SecretKeySpec(macKey, macAlgorithm));
} catch (GeneralSecurityException e) {
cipher = null;
mac = null;
throw e;
}
}
