0 概述
netty 通过JDK的SSLEngine，以SslHandler的方式提供对SSL/TLS 安全传输的支持，极大的简化了开发工作。本文主要讲述如何使用netty实现简单的https服务器。

1 SSL单向认证
所谓的单向认证，即客户端只验证服务端的合法性，服务端不会验证客户端。
单向认证过程的总结如下：
1.SSL客户端（浏览器）向服务端传送客户端 SSL协议的版本号、支持的加密算法种类、产生的随机数，以及其他可选信息。
2.服务端返回握手应答，向客户端传送确认SSL协议的版本号、加密算法种类、随机数以及其他信息。
3.服务端向客户端发送自己的证书，这个证书其实就是公钥，只是包含了很多信息，如证书的颁发机构，过期时间等等
4.客户端对服务端的证书进行认证，服务端的合法性校验包括：证书是否过期、发行服务器证书CA是否可靠、发行者证书的公钥能否解开服务器证书的“发行者数字签名”等
5.客户端随机产生一个用于后续通信的对称密钥，然后用服务端的公钥加密传输给服务端，通知服务端客户端的握手结束。
6.服务端解密获取客户端的对称密钥，同时通知客户端服务端的握手结束。
7.SSL的握手部分结束，SSL安全通道建立，客户端和服务端开始使用相同的对称密钥对数据进行加密，然后通过socket进行传输。

2 具体实现
<dependency>
<groupId>io.netty</groupId>
<artifactId>netty-all</artifactId>
<version>4.1.15.Final</version>
</dependency>
 
利用JDK的keytool 工具，生成服务端私钥和证书仓库。
执行如下命令：
keytool -genkey -keysize 2048 -validity 365 -keyalg RSA -dname “CN=localhost” -keypass hsc123 -storepass hsc123 -keystore local.jks

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.ssl.SslHandler;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLEngine;

/**
* Created by apple on 17/10/21.
*/
public class HttpsServer {

public static void start(final int port) throws Exception {
EventLoopGroup boss = new NioEventLoopGroup();
EventLoopGroup worker = new NioEventLoopGroup();
ServerBootstrap serverBootstrap = new ServerBootstrap();
try {
serverBootstrap.channel(NioServerSocketChannel.class)
.option(ChannelOption.SO_BACKLOG, 1024)
.group(boss, worker)
.childHandler(new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel ch) throws Exception {
SSLEngine sslEngine = SSLContextFactory.getSslContext().createSSLEngine();
sslEngine.setUseClientMode(false);
ch.pipeline().addLast(new SslHandler(sslEngine));
ch.pipeline().addLast("http-decoder", new HttpServerCodec());
ch.pipeline().addLast(new HttpsSeverHandler());
}
});
ChannelFuture future = serverBootstrap.bind(port).sync();
future.channel().closeFuture().sync();
} finally {
boss.shutdownGracefully();
worker.shutdownGracefully();
}

}

public static void main(String[] args) throws Exception {
start(7000);
}

}
 
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import java.io.FileInputStream;
import java.security.KeyStore;
import java.security.KeyStoreException;

/**
* Created by apple on 17/10/21.
*/
public class SSLContextFactory {

public static SSLContext getSslContext() throws Exception {
char[] passArray = "hsc123".toCharArray();
SSLContext sslContext = SSLContext.getInstance("TLSv1");
KeyStore ks = KeyStore.getInstance("JKS");
//加载keytool 生成的文件
FileInputStream inputStream = new FileInputStream("/Users/apple/local.jks");
ks.load(inputStream, passArray);
KeyManagerFactory kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
kmf.init(ks, passArray);
sslContext.init(kmf.getKeyManagers(), null, null);
inputStream.close();
return sslContext;

}
 
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.handler.codec.http.*;

/**
* Created by apple on 17/10/21.
*/
public class HttpsSeverHandler extends ChannelInboundHandlerAdapter {
@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
if (msg instanceof HttpRequest) {
HttpRequest request = (HttpRequest) msg;
boolean keepaLive = HttpUtil.isKeepAlive(request);
System.out.println("method" + request.method());
System.out.println("uri" + request.uri());
FullHttpResponse httpResponse = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK);
httpResponse.content().writeBytes("https".getBytes());
httpResponse.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/html;charset=UTF-8");
httpResponse.headers().setInt(HttpHeaderNames.CONTENT_LENGTH, httpResponse.content().readableBytes());
if (keepaLive) {
httpResponse.headers().set(HttpHeaderNames.CONNECTION, HttpHeaderValues.KEEP_ALIVE);
ctx.writeAndFlush(httpResponse);
} else {
ctx.writeAndFlush(httpResponse).addListener(ChannelFutureListener.CLOSE);
}
}
}
} 

3 测试
启动服务 输入https://127.0.0.1:7000

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版权声明：本文为CSDN博主「huangshanchun」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。
原文链接：https://blog.csdn.net/huangshanchun/article/details/78305964