added latency to cached status made protocol of the handshake configu…

…rable
slitherdmon · Jul 11, 2021 · bf98a7f · bf98a7f
1 parent c0d683e
commit bf98a7f
Show file tree

Hide file tree

Showing 6 changed files with 34 additions and 2 deletions.
diff --git a/README.md b/README.md
@@ -11,6 +11,7 @@ Im not planning on writing code to prevent Ultraviolet from crashing if you did
 This has implemented [tableflip](https://github.com/cloudflare/tableflip) which should make it able to reload/restart Ultraviolet without closing existing connections on Linux and macOS. Ultraviolet should still be usable on windows (testing purposes only pls). 
 Check their [documentation](https://pkg.go.dev/github.com/cloudflare/tableflip) to know what or how. 
 
+IMPORTANT: There is a limit of one 'parent' process. So when you reload Ultraviolet once you need to wait until the parent process is closed (all previous connections have been closed) before you can reload it again. 
 
 ## Command-Line Flags
 
@@ -48,6 +49,7 @@ time config values are based on go's duration formatting. They can be used in co
 |rateCooldown|1s|rateCooldown is the time which it will take before the rateLimit will be reset.|
 |stateUpdateCooldown|1s|The time it will assume that the state of the server isnt changed (that server isnt offline now while it was online the last time we checked). |
 |cacheStatus|false|Turn on or off whether it should cache the online cache of the server. If the server is recognized as offline it will send the offline status to the player.|
+|validProtocol|0|validProtocol is the protocol interger the handshake will have when sending the handshake to the backend. Its only necessary to have this when cacheStatus is on.|
 |cacheUpdateCooldown|1s|The time it will assume that the statys of the server isnt changed (including player count). |
 
 

diff --git a/config/types.go b/config/types.go
@@ -18,6 +18,7 @@ type ServerConfig struct {
 
 	CacheStatus         bool            `json:"cacheStatus"`
 	CacheUpdateCooldown string          `json:"cacheUpdateCooldown"`
+	ValidProtocol       int             `json:"validProtocol"`
 	OfflineStatus       mc.SimpleStatus `json:"offlineStatus"`
 
 	RateLimit           int    `json:"rateLimit"`

diff --git a/examples/server-example.json b/examples/server-example.json
@@ -6,6 +6,7 @@
     "sendProxyProtocol": false,
     "disconnectMessage": "Sorry, but the server is offline.",
     "cacheStatus": true,
+    "validProtocol": 755,
     "cacheUpdateCooldown": "5s",
     "offlineStatus": {
         "name": "Ultraviolet",

diff --git a/proxy/gateway.go b/proxy/gateway.go
@@ -136,6 +136,7 @@ func FileToWorkerConfig(cfg config.ServerConfig) WorkerServerConfig {
 		DialTimeout:         dialTimeout,
 		SendProxyProtocol:   cfg.SendProxyProtocol,
 		CacheStatus:         cfg.CacheStatus,
+		ValidProtocol:       cfg.ValidProtocol,
 		CacheUpdateCooldown: cacheCooldown,
 		OfflineStatus:       offlineStatusPk,
 		DisconnectPacket:    disconPk,

diff --git a/proxy/listener.go b/proxy/listener.go
@@ -6,6 +6,7 @@ import (
 	"io"
 	"log"
 	"net"
+	"time"
 
 	"github.com/realDragonium/Ultraviolet/mc"
 )
@@ -17,6 +18,7 @@ const (
 	PROXY McAction = iota
 	DISCONNECT
 	SEND_STATUS
+	SEND_STATUS_CACHE
 	CLOSE
 	ERROR
 )
@@ -30,6 +32,8 @@ func (state McAction) String() string {
 		text = "Disconnect"
 	case SEND_STATUS:
 		text = "Send Status"
+	case SEND_STATUS_CACHE:
+		text = "Send Status Cache"
 	case CLOSE:
 		text = "Close"
 	case ERROR:
@@ -68,6 +72,7 @@ type McAnswer struct {
 	Action         McAction
 	StatusPk       mc.Packet
 	ProxyCh        chan ProxyAction
+	Latency        time.Duration
 }
 
 func ServeListener(listener net.Listener, reqCh chan McRequest) {
@@ -152,6 +157,13 @@ func ReadConnection(c net.Conn, reqCh chan McRequest) {
 		pingPk, _ := conn.ReadPacket()
 		conn.WritePacket(pingPk)
 		conn.netConn.Close()
+	case SEND_STATUS_CACHE:
+		conn.ReadPacket()
+		conn.WritePacket(ans.StatusPk)
+		pingPk, _ := conn.ReadPacket()
+		time.Sleep(ans.Latency)
+		conn.WritePacket(pingPk)
+		conn.netConn.Close()
 	case CLOSE:
 		conn.netConn.Close()
 	}

diff --git a/proxy/worker.go b/proxy/worker.go
@@ -42,6 +42,7 @@ type WorkerServerConfig struct {
 	StateUpdateCooldown time.Duration
 	CacheStatus         bool
 	CacheUpdateCooldown time.Duration
+	ValidProtocol       int
 	OfflineStatus       mc.Packet
 	DisconnectPacket    mc.Packet
 	ProxyTo             string
@@ -130,6 +131,12 @@ func NewPrivateWorker(serverId int, cfg WorkerServerConfig) PrivateWorker {
 			return serverConn, nil
 		}
 	}
+	handshakePacket := mc.ServerBoundHandshake{
+		ProtocolVersion: mc.VarInt(cfg.ValidProtocol),
+		ServerAddress:   "Ultraviolet",
+		ServerPort:      25565,
+		NextState:       1,
+	}.Marshal()
 
 	return PrivateWorker{
 		proxyCh:           make(chan ProxyAction),
@@ -142,6 +149,7 @@ func NewPrivateWorker(serverId int, cfg WorkerServerConfig) PrivateWorker {
 		stateUpdateCh:     make(chan ServerState),
 		disconnectPacket:  cfg.DisconnectPacket,
 		serverConnFactory: createConnFeature,
+		statusHandshake:   handshakePacket,
 	}
 }
 
@@ -165,6 +173,8 @@ type PrivateWorker struct {
 	statusCache     bool
 	statusCooldown  time.Duration
 	statusCacheTime time.Time
+	statusLatency   time.Duration
+	statusHandshake mc.Packet
 
 	serverConnFactory func(net.Addr) func() (net.Conn, error)
 	disconnectPacket  mc.Packet
@@ -217,8 +227,9 @@ func (worker *PrivateWorker) HandleRequest(request McRequest) McAnswer {
 			worker.updateCacheStatus()
 		}
 		return McAnswer{
-			Action:   SEND_STATUS,
+			Action:   SEND_STATUS_CACHE,
 			StatusPk: worker.cachedStatus,
+			Latency:  worker.statusLatency,
 		}
 	}
 	var connFunc func() (net.Conn, error)
@@ -260,7 +271,6 @@ func (worker *PrivateWorker) updateServerState() {
 }
 
 func (worker *PrivateWorker) updateCacheStatus() {
-
 	connFunc := worker.serverConnFactory(&net.IPAddr{})
 	conn, err := connFunc()
 	go func(sleepTime time.Duration, updateCh chan ServerState) {
@@ -274,8 +284,13 @@ func (worker *PrivateWorker) updateCacheStatus() {
 		worker.state = ONLINE
 	}
 	mcConn := NewMcConn(conn)
+	mcConn.WritePacket(worker.statusHandshake)
 	mcConn.WritePacket(mc.ServerBoundRequest{}.Marshal())
 	worker.cachedStatus, _ = mcConn.ReadPacket()
+	beginTime := time.Now()
+	mcConn.WritePacket(mc.NewServerBoundPing().Marshal())
+	mcConn.ReadPacket()
+	worker.statusLatency = time.Since(beginTime)
 	conn.Close()
 	worker.statusCacheTime = time.Now()
 }