报文过大，可能导致解码失败,此时使用分包策略

app/src/main/java/com/virjar/g4proxy/HttpProxyService.java

@@ -128,24 +128,27 @@ public class HttpProxyService extends Service {
             }
         });
 
-        Log.i("weijia", "start G4Proxy front service");
-        Launcher.startHttpProxyService(3128);
 
-        Log.i("weijia", "start private network forward task");
         String clientKey = Settings.System.getString(getContentResolver(), Settings.Secure.ANDROID_ID);
-        ProxyClient.start(Constants.g4ProxyServerHost_1, Constants.g4ProxyServerPort, clientKey);
 
-        ProxyClient.start(Constants.g4ProxyServerHost_2, Constants.g4ProxyServerPort, clientKey);
+        Log.i("weijia", "start G4Proxy front service");
+        Launcher.startHttpProxyService(3128);
+
+//        Log.i("weijia", "start private network forward task");
+//
+//        ProxyClient.start(Constants.g4ProxyServerHost_1, Constants.g4ProxyServerPort, clientKey);
+//
+//        ProxyClient.start(Constants.g4ProxyServerHost_2, Constants.g4ProxyServerPort, clientKey);
 
 
         //新的代理服务器实现
 
         //默认使用3128，为了不影响之前的代码，先设置为3129
         LittelProxyBootstrap.setLittelServerPort(3129);
-        G4ProxyClient g4ProxyClient = new G4ProxyClient(Constants.g4ProxyServerHost_1, Constants.g4ProxyServerPort, clientKey);
+        G4ProxyClient g4ProxyClient = new G4ProxyClient("www.scumall.com", 50000, clientKey);
         g4ProxyClient.startup();
-        G4ProxyClient g4ProxyClient2 = new G4ProxyClient(Constants.g4ProxyServerHost_2, Constants.g4ProxyServerPort, clientKey);
-        g4ProxyClient2.startup();
+//        G4ProxyClient g4ProxyClient2 = new G4ProxyClient(Constants.g4ProxyServerHost_2, Constants.g4ProxyServerPort, clientKey);
+//        g4ProxyClient2.startup();
     }
 
 }

g4proxy-new/src/main/java/com/virjar/g4proxy_new/client/G4ProxyClient.java

@@ -57,7 +57,7 @@ public class G4ProxyClient {
             }
         });
 
-        Bootstrap join2NatServerBootStrap = new Bootstrap();
+        join2NatServerBootStrap = new Bootstrap();
         join2NatServerBootStrap.group(workerGroup);
         join2NatServerBootStrap.channel(NioSocketChannel.class);
         join2NatServerBootStrap.handler(new ChannelInitializer<SocketChannel>() {
@@ -70,6 +70,8 @@ public class G4ProxyClient {
                 ch.pipeline().addLast(new NatClientChannelHandler(G4ProxyClient.this));
             }
         });
+
+        forceReconnect();
     }
 
     private volatile boolean isConnecting = false;

g4proxy-new/src/main/java/com/virjar/g4proxy_new/client/LittleProxyChannelHandler.java

@@ -34,16 +34,36 @@ public class LittleProxyChannelHandler extends SimpleChannelInboundHandler<ByteB
             channel.close();
             return;
         }
-        NatMessage natMessage = new NatMessage();
 
-        byte[] bytes = new byte[msg.readableBytes()];
-        msg.readBytes(bytes);
-        natMessage.setData(bytes);
-        natMessage.setSerialNumber(seq);
-        natMessage.setType(NatMessage.P_TYPE_TRANSFER);
 
-        natChannel.writeAndFlush(natMessage);
-        log.info("receive data from littel proxy");
+        // 这里需要处理分包的问题，文件下载场景，这个包可能非常大。会导致 io.netty.handler.codec.TooLongFrameException: Adjusted frame length exceeds 1048576: 103335954 - discarded
+
+        int maxPackSize = Constant.MAX_FRAME_LENGTH - 128;
+        while (msg.readableBytes() > maxPackSize) {
+            byte[] bytes = new byte[maxPackSize];
+            msg.readBytes(bytes);
+
+            NatMessage natMessage = new NatMessage();
+            natMessage.setData(bytes);
+            natMessage.setSerialNumber(seq);
+            natMessage.setType(NatMessage.P_TYPE_TRANSFER);
+            //write,但是不需要 flush
+            natChannel.write(natMessage);
+            log.info("receive data from littel proxy");
+        }
+        if (msg.readableBytes() > 0) {
+            NatMessage natMessage = new NatMessage();
+            byte[] bytes = new byte[msg.readableBytes()];
+            msg.readBytes(bytes);
+            natMessage.setData(bytes);
+            natMessage.setSerialNumber(seq);
+            natMessage.setType(NatMessage.P_TYPE_TRANSFER);
+
+            natChannel.writeAndFlush(natMessage);
+            log.info("receive data from littel proxy");
+        } else {
+            natChannel.flush();
+        }
     }
 
 

g4proxy-new/src/main/java/com/virjar/g4proxy_new/protocol/Constant.java

@@ -4,6 +4,7 @@ import io.netty.channel.Channel;
 import io.netty.util.AttributeKey;
 
 public class Constant {
+    //单个报文，最大1M，超过1M需要分段
     public static final int MAX_FRAME_LENGTH = 1024 * 1024;
 
     public static final int LENGTH_FIELD_OFFSET = 0;

g4proxy-new/src/main/java/com/virjar/g4proxy_new/server/NatServerChannelHandler.java

@@ -174,4 +174,11 @@ public class NatServerChannelHandler extends SimpleChannelInboundHandler<NatMess
         clientManager.closeClient(clientId);
         super.channelInactive(ctx);
     }
+
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        //TODO 这里应该怎么办？？？
+        super.exceptionCaught(ctx, cause);
+    }
 }

g4proxy-new/src/main/java/com/virjar/g4proxy_new/server/UserMappingChannelHandler.java

@@ -75,15 +75,33 @@ public class UserMappingChannelHandler extends SimpleChannelInboundHandler<ByteB
             return;
         }
 
-        byte[] bytes = new byte[msg.readableBytes()];
-        msg.readBytes(bytes);
 
-        NatMessage natMessage = new NatMessage();
-        natMessage.setType(NatMessage.P_TYPE_TRANSFER);
-        natMessage.setSerialNumber(seq);
-        natMessage.setData(bytes);
-        client.getNatChannel().writeAndFlush(natMessage);
-        log.info("forward data to client:{}", clientId);
+        int maxPackSize = Constant.MAX_FRAME_LENGTH - 128;
+        while (msg.readableBytes() > maxPackSize) {
+            byte[] bytes = new byte[maxPackSize];
+            msg.readBytes(bytes);
+
+            NatMessage natMessage = new NatMessage();
+            natMessage.setData(bytes);
+            natMessage.setSerialNumber(seq);
+            natMessage.setType(NatMessage.P_TYPE_TRANSFER);
+            //write,但是不需要 flush
+            client.getNatChannel().write(natMessage);
+            log.info("receive data from littel proxy");
+        }
+        if (msg.readableBytes() > 0) {
+            NatMessage natMessage = new NatMessage();
+            byte[] bytes = new byte[msg.readableBytes()];
+            msg.readBytes(bytes);
+            natMessage.setData(bytes);
+            natMessage.setSerialNumber(seq);
+            natMessage.setType(NatMessage.P_TYPE_TRANSFER);
+
+            client.getNatChannel().writeAndFlush(natMessage);
+            log.info("receive data from littel proxy");
+        } else {
+            client.getNatChannel().flush();
+        }
     }
 
 

g4proxy-new/src/main/java/com/virjar/g4proxy_new/server/client/ClientManager.java

@@ -27,28 +27,32 @@ public class ClientManager {
 
     public boolean registerNewClient(String client, Channel channel) {
         NatClientImage natClientImage = natClientImageMap.get(client);
+        Integer mappingPort;
         if (natClientImage != null) {
-            natClientImage.updateChannel(channel);
-            return true;
+            log.warn("update nat channel");
+            natClientImage.getNatChannel().close();
+            natClientImage.closeAllUserChannel();
+            mappingPort = natClientImage.getMappingPort();
+        } else {
+            mappingPort = AvailablePortResManager.allocate();
+            if (mappingPort == null) {
+                log.error("failed to allocate port");
+                return false;
+            }
+            ChannelFuture channelFuture = userMappingBootstrap.bind(mappingPort);
+            try {
+                channelFuture.get();
+            } catch (Exception e) {
+                log.error("wait for port binding error", e);
+                return false;
+            }
+            if (!channelFuture.isSuccess()) {
+                log.warn("bind mapping port:{} failed", mappingPort, channelFuture.cause());
+                return false;
+            }
         }
 
-        Integer mappingPort = AvailablePortResManager.allocate();
-        if (mappingPort == null) {
-            log.error("failed to allocate port");
-            return false;
-        }
 
-        ChannelFuture channelFuture = userMappingBootstrap.bind(mappingPort);
-        try {
-            channelFuture.get();
-        } catch (Exception e) {
-            log.error("wait for port binding error", e);
-            return false;
-        }
-        if (!channelFuture.isSuccess()) {
-            log.warn("bind mapping port:{} failed", mappingPort, channelFuture.cause());
-            return false;
-        }
         channel.attr(Constant.NAT_CHANNEL_CLIENT_KEY).set(client);
         clientPortBiMap.put(client, mappingPort);
         natClientImage = new NatClientImage(client, mappingPort, channel);
@@ -62,7 +66,11 @@ public class ClientManager {
     }
 
     public NatClientImage getClient(Integer mappingPort) {
-        return natClientImageMap.get(clientPortBiMap.inverse().get(mappingPort));
+        String clientId = clientPortBiMap.inverse().get(mappingPort);
+        if (clientId == null) {
+            return null;
+        }
+        return natClientImageMap.get(clientId);
     }
 
 

g4proxy-new/src/main/java/com/virjar/g4proxy_new/server/client/NatClientImage.java

@@ -15,6 +15,7 @@ public class NatClientImage {
     @Getter
     private String clientId;
     private AtomicLong seqGenerator = new AtomicLong(0);
+    @Getter
     private int mappingPort;
     @Getter
     private Channel natChannel;
@@ -67,5 +68,6 @@ public class NatClientImage {
         for (Channel channel : userMappingChannels.values()) {
             releaseConnection(channel);
         }
+
     }
 }