Java socket通信实现DES加密与解密
(2037) DES是对称加密算法的其中一个，用一个密钥进行加密解密数据，安全性能比较低，效率较高，一些不太重要的数据可以使用DES加密算法进行加密解密传输，其他的3DES与AES用法类似。
流程图
首先认真看一下流程图，在脑海里过一遍，然后其实也就是分为以下两个过程，传输完密钥后，就可以使用这个密钥加密数据发送给服务器，服务器拿密钥解密数据，完事。
OK，直接贴代码吧，注意下Base64转码传输以及密钥的传输就行了。
Server 端
package des;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.security.InvalidKeyException;
import java.security.Key;
import javax.crypto.BadPaddingException;
import javax.crypto.IllegalBlockSizeException;
//DES加密
public class Server {
public void openServer() throws IOException{
ServerSocket serverSocket=new ServerSocket(4400);
Thread thread=null;
Socket socket=null;
while(true){
socket=serverSocket.accept();
thread=new Thread( new myThread(socket));
thread.start();
}
}
public static void main(String[] args){
try {
new Server().openServer();
} catch (IOException e) {
System.out.println(e.getMessage());
e.printStackTrace();
}
}
}
class myThread implements Runnable{
private Socket socket;
BufferedReader is;
PrintWriter os;
String passwd="bayaojiu.com";
Key key=null;
public myThread(Socket socket){
this.socket=socket;
try {
is=new BufferedReader(new InputStreamReader(socket.getInputStream()));
os=new PrintWriter(socket.getOutputStream());
} catch (IOException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
public void run(){
try {
DesKeyUtils des=new DesKeyUtils();
//接收到base64编码后的密钥字符串
String request=is.readLine();
//base64解密为普通二进制数组
byte decodeMsg[]=des.decoder.decode(request);
//根据二进制数组转换成key对象
key=des.strToKey(decodeMsg);
String passwdClient=null;
//等待客户端发送密文
String response=is.readLine();
//用密钥将密文解密
passwdClient=des.decodeKey(response.getBytes(),key);
System.out.println("receive:"+passwdClient);
//等于密码就通过验证了
if(passwdClient.equals(passwd))
os.println("yes");
else
os.println("false");
os.close();
is.close();
socket.close();
} catch (IOException | InvalidKeyException | IllegalBlockSizeException | BadPaddingException e) {
}
}
}
Client 端
package des;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.security.Key;
public class Client {
private static DesKeyUtils des;
private static Key publicKey;
public static void main(String[] args) throws IOException {
des=new DesKeyUtils();
//生成密钥
publicKey=des.generateSecrety();
connectServer();
}
public static void connectServer() throws IOException{
String passwd="bayaojiu.com";
Socket socket=new Socket("127.0.0.1",4400);
PrintWriter os=new PrintWriter(socket.getOutputStream());
BufferedReader is=new BufferedReader(new InputStreamReader(socket.getInputStream()));
//转换成二进制数据进行保存
byte[]encodeData=publicKey.getEncoded();
//因为DES生成二进制数据中有ascii码无法显示的字符，传输的时候会丢失，所以我们使用base64进行无损传输
String request=des.encoder.encodeToString(encodeData);
//发送给服务器
os.println(request);
os.flush();
//根据Key对象对发送的内容进行加密，然后再将加密后的密文经过base64编码
String decodeMes=des.encodeKey(passwd.getBytes("UTF-8"),publicKey);
//发送密文给服务器
os.println(decodeMes);
os.flush();
//查看是否成功验证
System.out.println(is.readLine());
os.close();
is.close();
socket.close();
}
}
然后我抽出来了一个加密解密类 DesKeyUtils
package des;
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.util.Base64;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
public class DesKeyUtils {
private static Cipher cipher;
final public static Base64.Decoder decoder=Base64.getDecoder();
final public static Base64.Encoder encoder=Base64.getEncoder();
//初始化
public DesKeyUtils(){
try {
cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
} catch (NoSuchAlgorithmException | NoSuchPaddingException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
//解密
public static String decodeKey(byte [] encodeKey,Key secretkey) throws InvalidKeyException, IllegalBlockSizeException, BadPaddingException{
//先将经过base64编码的密文还原
encodeKey=decoder.decode(encodeKey);
try {
cipher.init(Cipher.DECRYPT_MODE, secretkey);
//将原密文进行解密
return new String(cipher.doFinal(encodeKey),"UTF-8");
}catch(Exception e){
e.printStackTrace();
return null;
}
}
//加密
public static String encodeKey(byte[] decodekey,Key secretkey){
try {
cipher.init(Cipher.ENCRYPT_MODE, secretkey);
//将明文加密成密文
byte[] encodeMsg=cipher.doFinal(decodekey);
//将密文经过base64加密
return new String(encoder.encode(encodeMsg),"UTF-8");
} catch (IllegalBlockSizeException | BadPaddingException | InvalidKeyException | UnsupportedEncodingException e) {
e.printStackTrace();
return null;
}
}
//生成密钥
public static Key generateSecrety(){
KeyGenerator key;
try {
//生成
key = KeyGenerator.getInstance("DES");
key.init(56);
SecretKey secretKey=key.generateKey();
byte[] bytesKey=secretKey.getEncoded();
//转换
DESKeySpec desKeySpec=new DESKeySpec(bytesKey);
SecretKeyFactory factory =SecretKeyFactory.getInstance("DES");
Key convertSecretKey=factory.generateSecret(desKeySpec);
return convertSecretKey;
} catch (NoSuchAlgorithmException | InvalidKeyException | InvalidKeySpecException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
return null;
}
}
//将二进制转换成Key对象，跟转换密钥那里差不多
public static Key strToKey(byte[] data){
Key convertSecretKey1=null;
try {
DESKeySpec desKeySpec=new DESKeySpec(data);
SecretKeyFactory factory = SecretKeyFactory.getInstance("DES");
convertSecretKey1=factory.generateSecret(desKeySpec);
return convertSecretKey1;
} catch (NoSuchAlgorithmException | InvalidKeySpecException | InvalidKeyException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
return null;
}
}
}
运行结果
Server：
———————————————————————————-
Client：
参考：