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Fixed bigger messages bug, added working login and register, other smaller fixes

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This commit is contained in:
Mariano Riefolo 2024-04-08 17:47:34 +02:00
parent 4588be4d74
commit 68ff067a5e
6 changed files with 134 additions and 66 deletions
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3
src/main/java/controllers/MessageForwarder.java
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@ -1,5 +1,6 @@
package controllers;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
@ -14,7 +15,7 @@ public class MessageForwarder {
idThread.put(id, thread);
}
public static void sendTo(int id, String message, int senderId) {
public static void sendTo(int id, String message, int senderId) throws IOException {
idThread.get(id).sendMessage(message, senderId);
}
}

73
src/main/java/controllers/ServerThread.java
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@ -13,7 +13,7 @@ import static controllers.Database.registerAccount;
public class ServerThread extends Thread {
private final Socket client;
private BufferedReader fromClient;
private PrintWriter toClient;
private BufferedWriter toClient;
private final Rsa rsa;
private BigInteger clientE, clientN;
private int clientId;
@ -26,13 +26,21 @@ public class ServerThread extends Thread {
public void run() {
try {
fromClient = new BufferedReader(new InputStreamReader(client.getInputStream()));
toClient = new PrintWriter(client.getOutputStream(),true);
toClient = new BufferedWriter(new OutputStreamWriter(client.getOutputStream()));
} catch (IOException e) {
throw new RuntimeException(e);
}
toClient.println(rsa.getE().toString());
toClient.println(rsa.getN().toString());
try {
send(rsa.getE().toString());
} catch (IOException e) {
throw new RuntimeException(e);
}
try {
send(rsa.getN().toString());
} catch (IOException e) {
throw new RuntimeException(e);
}
try {
clientE = new BigInteger(fromClient.readLine());
@ -43,8 +51,9 @@ public class ServerThread extends Thread {
for (;;) {
String operation;
sendEncrypted("Quale operazione vuoi effettuare? (REGISTER|LOGIN): ");
try {
operation = rsa.decrypt(new BigInteger(fromClient.readLine()));
operation = rsa.decrypt(fromClient.readLine());
} catch (IOException e) {
throw new RuntimeException(e);
}
@ -52,10 +61,10 @@ public class ServerThread extends Thread {
String username, password;
try {
toClient.print("Inserisci l'username: ");
username = rsa.decrypt(new BigInteger(fromClient.readLine()));
toClient.print("Inserisci la password: ");
password = rsa.decrypt(new BigInteger(fromClient.readLine()));
sendEncrypted("Inserisci l'username: ");
username = rsa.decrypt(fromClient.readLine());
sendEncrypted("Inserisci la password: ");
password = rsa.decrypt(fromClient.readLine());
} catch (IOException e) {
throw new RuntimeException(e);
}
@ -64,19 +73,23 @@ public class ServerThread extends Thread {
if ("LOGIN".equals(operation)) {
if (login(username, password)) {
Account account = getAccount(username, password);
toClient.println(rsa.encrypt(String.valueOf(account.n()), clientE, clientN).toString());
toClient.println(rsa.encrypt(String.valueOf(account.d()), clientE, clientN).toString());
toClient.println(rsa.encrypt(String.valueOf(account.e()), clientE, clientN).toString());
toClient.println(rsa.encrypt("SUCCESS", clientE, clientN).toString());
if (account == null) {
sendEncrypted("FAIL");
break;
}
sendEncrypted(String.valueOf(account.n()));
sendEncrypted(String.valueOf(account.e()));
sendEncrypted(String.valueOf(account.d()));
sendEncrypted("SUCCESS");
break;
}
} else if ("REGISTER".equals(operation)) {
if (register(username, password)) {
toClient.println(rsa.encrypt("SUCCESS", clientE, clientN).toString());
sendEncrypted("SUCCESS");
break;
}
} else {
toClient.println(rsa.encrypt("FAIL", clientE, clientN).toString());
sendEncrypted("FAIL");
}
}
@ -87,17 +100,35 @@ public class ServerThread extends Thread {
for (;;) {
try {
recipientId = Integer.parseInt(rsa.decrypt(new BigInteger(fromClient.readLine())));
message = rsa.decrypt(new BigInteger(fromClient.readLine()));
recipientId = Integer.parseInt(rsa.decrypt(fromClient.readLine()));
message = rsa.decrypt(fromClient.readLine());
} catch (IOException e) {
throw new RuntimeException(e);
}
if (message == null || "DISCONNECT".equals(message)) break;
try {
MessageForwarder.sendTo(recipientId, message, clientId);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}
private void sendEncrypted(String text) {
try {
send(rsa.encrypt(text, clientE, clientN));
} catch (Exception e) {
System.err.println(e.getMessage());
}
}
public void send(String message) throws IOException {
toClient.write(message);
toClient.newLine();
toClient.flush();
}
private boolean login(String username, String password) {
Account account = getAccount(username, password);
@ -119,9 +150,9 @@ public class ServerThread extends Thread {
return clientId != -1;
}
public void sendMessage(String message, int sender) {
toClient.println("INCOMING");
toClient.println(sender);
toClient.println(message);
public void sendMessage(String message, int sender) throws IOException {
send("INCOMING");
send(String.valueOf(sender));
send(message);
}
}

36
src/main/java/models/Rsa.java
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@ -6,6 +6,7 @@ import java.security.SecureRandom;
public class Rsa {
private final BigInteger e, d, n;
private static final int CHUNK_SIZE = 64;
public Rsa(int numberOfBytes) {
BigInteger p = generatePrime(numberOfBytes);
@ -29,16 +30,39 @@ public class Rsa {
return new BigInteger(numberOfBytes, 100, secureRandom).nextProbablePrime();
}
public BigInteger encrypt(String message, BigInteger e, BigInteger n) {
BigInteger plaintext = toHex(message);
return plaintext.modPow(e, n);
public String encrypt(String message, BigInteger e, BigInteger n) {
StringBuilder encryptedMessage = new StringBuilder();
for (int i = 0; i < message.length(); i += CHUNK_SIZE) {
String chunk = message.substring(i, Math.min(i + CHUNK_SIZE, message.length()));
BigInteger plaintext = toHex(chunk);
BigInteger encryptedChunk = plaintext.modPow(e, n);
encryptedMessage.append(encryptedChunk).append("|");
}
public String decrypt(BigInteger ciphertext) {
BigInteger plaintext = ciphertext.modPow(d, n);
return fromHex(plaintext);
return encryptedMessage.toString();
//BigInteger plaintext = toHex(message);
//return plaintext.modPow(e, n);
}
public String decrypt(String ciphertext) {
StringBuilder decryptedMessage = new StringBuilder();
String[] chunks = ciphertext.split("\\|");
for (String chunk : chunks) {
BigInteger encryptedChunk = new BigInteger(chunk);
BigInteger decryptedChunk = encryptedChunk.modPow(d, n);
decryptedMessage.append(fromHex(decryptedChunk));
}
return decryptedMessage.toString();
//BigInteger plaintext = ciphertext.modPow(d, n);
//return fromHex(plaintext);
}
private static BigInteger toHex(String arg) {
return new BigInteger(1, arg.getBytes(StandardCharsets.UTF_8));
}

39
src/main/java/views/Client.java
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@ -1,14 +1,11 @@
package views;
import models.*;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.encrypt.AesBytesEncryptor;
import org.springframework.security.crypto.password.PasswordEncoder;
import java.io.*;
import java.math.BigInteger;
import java.net.Socket;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
@ -16,18 +13,18 @@ import java.util.Arrays;
public class Client{
private static Rsa rsa;
private static DataInputStream in;
private static PrintWriter out;
private static BufferedReader in;
private static BufferedWriter out;
private static BigInteger se,sn;
private static final String salt = "50726f6653616e736f6e6e65";
public static void connect() throws Exception {
//connessione al server e creazione thread client
Socket clientSocket = new Socket("localhost", 21324);
//Creazione canale di comunicazione Full-Duplex
in = new DataInputStream(clientSocket.getInputStream());
out = new PrintWriter(clientSocket.getOutputStream(),true);
in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
out = new BufferedWriter(new OutputStreamWriter(clientSocket.getOutputStream()));
//ricezione chiave pubblica del server
se = new BigInteger(in.readLine());
@ -37,25 +34,35 @@ public class Client{
rsa = new Rsa(1024);
BigInteger nt = rsa.getN();
BigInteger et = rsa.getE();
//invio chiave pubblica temporanea al server
out.println(et);
out.println(nt);
send(String.valueOf(et));
send(String.valueOf(nt));
}
protected static void login() throws IOException, NoSuchAlgorithmException {
protected static void login(String password) throws IOException, NoSuchAlgorithmException {
//se le credenziali sono giuste il server invia le chiavi definitive
BigInteger n = new BigInteger(rsa.decrypt(new BigInteger(in.readLine())));
BigInteger e = new BigInteger(rsa.decrypt(new BigInteger(in.readLine())));
BigInteger d = new BigInteger(new AesBytesEncryptor("Password", "").decrypt(new BigInteger(rsa.decrypt(new BigInteger(in.readLine()))).toByteArray()));
BigInteger n = new BigInteger(rsa.decrypt(in.readLine()));
BigInteger e = new BigInteger(rsa.decrypt(in.readLine()));
BigInteger d = new BigInteger(new AesBytesEncryptor(password, salt).decrypt(new BigInteger(rsa.decrypt(in.readLine())).toByteArray()));
rsa = new Rsa(e, d, n);
}
protected static void register() throws NoSuchAlgorithmException, IOException {
protected static void register(String password) throws NoSuchAlgorithmException, IOException {
BigInteger d = rsa.getD();
//Invio Username,password e Chiave privata AESata
out.println(new AesBytesEncryptor("Password", "").encrypt(d.toByteArray()));
sendEncrypted(Arrays.toString(new AesBytesEncryptor(password, salt).encrypt(d.toByteArray())));
}
private static void sendEncrypted(String text) throws IOException {
send(rsa.encrypt(text, se, sn));
}
public static void send(String message) throws IOException {
out.write(message);
out.newLine();
out.flush();
}
public static void main(String[] args) throws Exception {
connect();

12
src/main/java/views/ClientReceiveThread.java
View File

@ -2,14 +2,13 @@ package views;
import models.Rsa;
import java.io.DataInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.math.BigInteger;
public class ClientReceiveThread extends Thread{
private static DataInputStream in;
private static Rsa rsa;
public ClientReceiveThread(DataInputStream in, Rsa rsa){
private final BufferedReader in;
private final Rsa rsa;
public ClientReceiveThread(BufferedReader in, Rsa rsa){
this.in=in;
this.rsa=rsa;
}
@ -17,8 +16,7 @@ public class ClientReceiveThread extends Thread{
while (true){
try {
String s = in.readLine();
System.out.println(s);
System.out.println(rsa.decrypt(new BigInteger(s)));
System.out.print(rsa.decrypt(s));
} catch (IOException e) {
throw new RuntimeException(e);
}

31
src/main/java/views/ClientSendThread.java
View File

@ -7,40 +7,41 @@ import java.math.BigInteger;
import java.security.NoSuchAlgorithmException;
public class ClientSendThread extends Thread{
private static PrintWriter out;
private static BigInteger se,sn;
private static Rsa rsa;
public ClientSendThread(PrintWriter out,BigInteger se, BigInteger sn,Rsa rsa){
private final BufferedWriter out;
private final BigInteger se,sn;
private final Rsa rsa;
public ClientSendThread(BufferedWriter out,BigInteger se, BigInteger sn,Rsa rsa){
this.out = out;
this.se = se;
this.sn=sn;
this.rsa=rsa;
}
public void run(){
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
while (true) {
try {
String s = br.readLine();
out.println(rsa.encrypt(s, se, sn));
out.flush();
send(rsa.encrypt(s, se, sn));
if("REGISTER".equals(s)){
s = br.readLine();
out.println(rsa.encrypt(s, se, sn));
send(rsa.encrypt(s, se, sn));
s = br.readLine();
out.println(rsa.encrypt(s, se, sn));
send(rsa.encrypt(s, se, sn));
try {
Client.register();
Client.register(s);
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException(e);
}
}
else if("LOGIN".equals(s)){
s = br.readLine();
out.println(rsa.encrypt(s, se, sn));
send(rsa.encrypt(s, se, sn));
s = br.readLine();
out.println(rsa.encrypt(s, se, sn));
send(rsa.encrypt(s, se, sn));
try {
Client.login();
Client.login(s);
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException(e);
}
@ -50,4 +51,10 @@ public class ClientSendThread extends Thread{
}
}
}
public void send(String message) throws IOException {
out.write(message);
out.newLine();
out.flush();
}
}