protocol cache expiration, fix dns blocking thread, fix 1.8 fallback

src/main/kotlin/com/viaversion/aas/handler/BackEndInit.kt

@@ -7,13 +7,16 @@ import com.viaversion.viaversion.protocol.ProtocolPipelineImpl
 import io.netty.channel.Channel
 import io.netty.channel.ChannelInitializer
 import io.netty.handler.timeout.ReadTimeoutHandler
+import java.net.InetSocketAddress
+import java.net.URI
 import java.util.concurrent.TimeUnit
 
-class BackEndInit(val connectionData: ConnectionData) : ChannelInitializer<Channel>() {
+class BackEndInit(val connectionData: ConnectionData, val proxyUri: URI?, val proxyAddress: InetSocketAddress?) :
+    ChannelInitializer<Channel>() {
     override fun initChannel(ch: Channel) {
         val user = UserConnectionImpl(ch, true)
         ProtocolPipelineImpl(user)
-        ch.pipeline().also { addProxyHandler(it) }
+        ch.pipeline().also { addProxyHandler(it, proxyUri, proxyAddress) }
             // "crypto"
             .addLast("frame", FrameCodec())
             // compress

src/main/kotlin/com/viaversion/aas/handler/Util.kt

@@ -1,8 +1,6 @@
 package com.viaversion.aas.handler
 
-import com.viaversion.aas.AspirinServer
 import com.viaversion.aas.codec.packet.Packet
-import com.viaversion.aas.config.VIAaaSConfig
 import com.viaversion.aas.readRemainingBytes
 import com.viaversion.aas.send
 import com.viaversion.viaversion.api.protocol.version.ProtocolVersion
@@ -14,6 +12,7 @@ import io.netty.handler.proxy.HttpProxyHandler
 import io.netty.handler.proxy.Socks4ProxyHandler
 import io.netty.handler.proxy.Socks5ProxyHandler
 import java.net.InetSocketAddress
+import java.net.URI
 
 fun forward(handler: MinecraftHandler, packet: Packet, flush: Boolean = false) {
     send(handler.other!!, packet, flush)
@@ -21,10 +20,8 @@ fun forward(handler: MinecraftHandler, packet: Packet, flush: Boolean = false) {
 
 fun is17(handler: MinecraftHandler) = handler.data.frontVer!! <= ProtocolVersion.v1_7_6.version
 
-fun addProxyHandler(pipe: ChannelPipeline) {
-    val proxyUri = VIAaaSConfig.backendProxy
+fun addProxyHandler(pipe: ChannelPipeline, proxyUri: URI?, socket: InetSocketAddress?) {
     if (proxyUri != null) {
-        val socket = InetSocketAddress(AspirinServer.dnsResolver.resolve(proxyUri.host).get(), proxyUri.port)
         val user = proxyUri.userInfo?.substringBefore(':')
         val pass = proxyUri.userInfo?.substringAfter(':')
         val handler = when (proxyUri.scheme) {

src/main/kotlin/com/viaversion/aas/handler/autoprotocol/ProtocolDetector.kt

@@ -8,12 +8,14 @@ import com.viaversion.aas.codec.FrameCodec
 import com.viaversion.aas.codec.MinecraftCodec
 import com.viaversion.aas.codec.packet.handshake.Handshake
 import com.viaversion.aas.codec.packet.status.StatusRequest
+import com.viaversion.aas.config.VIAaaSConfig
 import com.viaversion.aas.handler.ConnectionData
 import com.viaversion.aas.handler.MinecraftHandler
 import com.viaversion.aas.handler.addProxyHandler
 import com.viaversion.aas.send
 import com.viaversion.viaversion.api.protocol.packet.State
 import com.viaversion.viaversion.api.protocol.version.ProtocolVersion
+import io.ktor.server.netty.*
 import io.netty.bootstrap.Bootstrap
 import io.netty.channel.Channel
 import io.netty.channel.ChannelFutureListener
@@ -21,52 +23,60 @@ import io.netty.channel.ChannelInitializer
 import io.netty.channel.ChannelOption
 import io.netty.handler.timeout.ReadTimeoutHandler
 import io.netty.resolver.NoopAddressResolverGroup
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.launch
 import java.net.InetSocketAddress
 import java.util.concurrent.CompletableFuture
 import java.util.concurrent.TimeUnit
 
 object ProtocolDetector {
     private val SERVER_VER = CacheBuilder.newBuilder()
-        .expireAfterAccess(30, TimeUnit.SECONDS)
+        .expireAfterWrite(30, TimeUnit.SECONDS)
         .build<InetSocketAddress, CompletableFuture<ProtocolVersion>>(CacheLoader.from { address ->
             val future = CompletableFuture<ProtocolVersion>()
-            try {
-                val ch = Bootstrap()
-                    .group(AspirinServer.childLoop)
-                    .resolver(NoopAddressResolverGroup.INSTANCE)
-                    .channelFactory(channelSocketFactory(AspirinServer.childLoop))
-                    .option(ChannelOption.TCP_NODELAY, true)
-                    .option(ChannelOption.IP_TOS, 0x18)
-                    .handler(object : ChannelInitializer<Channel>() {
-                        override fun initChannel(channel: Channel) {
-                            val data = ConnectionData(
-                                channel,
-                                state = ProtocolDetectionState(future),
-                                frontVer = -1
-                            )
-                            channel.pipeline().also { addProxyHandler(it) }
-                                .addLast("timeout", ReadTimeoutHandler(30, TimeUnit.SECONDS))
-                                .addLast("frame", FrameCodec())
-                                .addLast("mc", MinecraftCodec())
-                                .addLast("handler", MinecraftHandler(data, frontEnd = false))
+            GlobalScope.launch {
+                try {
+                    val proxyUri = VIAaaSConfig.backendProxy
+                    val proxySocket = if (proxyUri == null) null else {
+                        InetSocketAddress(AspirinServer.dnsResolver.resolve(proxyUri.host).suspendAwait(), proxyUri.port)
+                    }
+                    val ch = Bootstrap()
+                        .group(AspirinServer.childLoop)
+                        .resolver(NoopAddressResolverGroup.INSTANCE)
+                        .channelFactory(channelSocketFactory(AspirinServer.childLoop))
+                        .option(ChannelOption.TCP_NODELAY, true)
+                        .option(ChannelOption.IP_TOS, 0x18)
+                        .handler(object : ChannelInitializer<Channel>() {
+                            override fun initChannel(channel: Channel) {
+                                val data = ConnectionData(
+                                    channel,
+                                    state = ProtocolDetectionState(future),
+                                    frontVer = -1
+                                )
+                                channel.pipeline().also { addProxyHandler(it, proxyUri, proxySocket) }
+                                    .addLast("timeout", ReadTimeoutHandler(30, TimeUnit.SECONDS))
+                                    .addLast("frame", FrameCodec())
+                                    .addLast("mc", MinecraftCodec())
+                                    .addLast("handler", MinecraftHandler(data, frontEnd = false))
+                            }
+                        })
+                        .connect(address!!)
+                    ch.addListener(ChannelFutureListener {
+                        if (!it.isSuccess) {
+                            future.completeExceptionally(it.cause())
+                        } else {
+                            val handshake = Handshake()
+                            handshake.address = address.hostString
+                            handshake.port = address.port
+                            handshake.protocolId = -1
+                            handshake.nextState = State.STATUS
+                            send(ch.channel(), handshake)
+                            send(ch.channel(), StatusRequest(), flush = true)
                         }
                     })
-                    .connect(address!!)
-                ch.addListener(ChannelFutureListener {
-                    if (!it.isSuccess) {
-                        future.completeExceptionally(it.cause())
-                    } else {
-                        val handshake = Handshake()
-                        handshake.address = address.hostString
-                        handshake.port = address.port
-                        handshake.protocolId = -1
-                        handshake.nextState = State.STATUS
-                        send(ch.channel(), handshake)
-                        send(ch.channel(), StatusRequest(), flush = true)
-                    }
-                })
-            } catch (throwable: Throwable) {
-                future.completeExceptionally(throwable)
+                } catch (throwable: Throwable) {
+                    future.completeExceptionally(throwable)
+                }
             }
             future
         })

src/main/kotlin/com/viaversion/aas/handler/state/Util.kt

@@ -19,19 +19,22 @@ import io.netty.channel.socket.SocketChannel
 import io.netty.handler.proxy.ProxyHandler
 import io.netty.resolver.NoopAddressResolverGroup
 import kotlinx.coroutines.future.await
-import kotlinx.coroutines.withTimeoutOrNull
+import kotlinx.coroutines.withTimeout
 import java.net.Inet4Address
 import java.net.InetSocketAddress
+import java.net.URI
 
 private suspend fun createBackChannel(
     handler: MinecraftHandler,
     socketAddr: InetSocketAddress,
     state: State,
-    extraData: String?
+    extraData: String?,
+    proxyUri: URI?,
+    proxyAddress: InetSocketAddress?
 ): Channel {
     val loop = handler.data.frontChannel.eventLoop()
     val channel = Bootstrap()
-        .handler(BackEndInit(handler.data))
+        .handler(BackEndInit(handler.data, proxyUri, proxyAddress))
         .channelFactory(channelSocketFactory(loop.parent()))
         .group(loop)
         .option(ChannelOption.WRITE_BUFFER_WATER_MARK, AspirinServer.bufferWaterMark)
@@ -64,23 +67,24 @@ private suspend fun createBackChannel(
 
 private suspend fun autoDetectVersion(handler: MinecraftHandler, socketAddr: InetSocketAddress) {
     if (handler.data.backServerVer == -2) { // Auto
+        var detectedProtocol: ProtocolVersion? = null
         try {
-            val detectedProtocol = withTimeoutOrNull(10_000) {
+            detectedProtocol = withTimeout(10_000) {
                 ProtocolDetector.detectVersion(socketAddr).await()
             }
-
-            if (detectedProtocol != null
-                && detectedProtocol.version !in arrayOf(-1, -2)
-                && ProtocolVersion.isRegistered(detectedProtocol.version)
-            ) {
-                handler.data.backServerVer = detectedProtocol.version
-            } else {
-                handler.data.backServerVer = 47 // fallback 1.8
-            }
         } catch (e: Exception) {
-            mcLogger.warn("Failed to auto-detect version for $socketAddr: $e")
+            mcLogger.warn("Failed to detect version of $socketAddr: $e")
             mcLogger.debug("Stacktrace: ", e)
         }
+
+        if (detectedProtocol != null
+            && detectedProtocol.version !in arrayOf(-1, -2)
+            && ProtocolVersion.isRegistered(detectedProtocol.version)
+        ) {
+            handler.data.backServerVer = detectedProtocol.version
+        } else {
+            handler.data.backServerVer = 47 // fallback 1.8
+        }
     }
 }
 
@@ -101,7 +105,12 @@ private suspend fun tryBackAddresses(
                 throw StacklessException("Not allowed")
             }
 
-            createBackChannel(handler, socketAddr, state, extraData)
+            val proxyUri = VIAaaSConfig.backendProxy
+            val proxySocket = if (proxyUri == null) null else {
+                InetSocketAddress(AspirinServer.dnsResolver.resolve(proxyUri.host).suspendAwait(), proxyUri.port)
+            }
+
+            createBackChannel(handler, socketAddr, state, extraData, proxyUri, proxySocket)
             return // Finally it worked!
         } catch (e: Exception) {
             latestException = e