fix dns client

Tun/Punchnet/DNSClient.swift

@@ -0,0 +1,102 @@
+//
+//  DNSClient.swift
+//  Tun
+//
+//  Created by 安礼成 on 2025/12/10.
+//
+
+import Foundation
+import NIOCore
+import NIOPosix
+
+// 处理和sn-server服务器之间的通讯
+@available(macOS 14, *)
+actor DNSClient {
+    private let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
+    private let asyncChannel: NIOAsyncChannel<AddressedEnvelope<ByteBuffer>, AddressedEnvelope<ByteBuffer>>
+    private let (writeStream, writeContinuation) = AsyncStream.makeStream(of: Data.self, bufferingPolicy: .unbounded)
+    
+    private let logger: SDLLogger
+    private let dnsServerAddress: SocketAddress
+    
+    public let packetFlow: AsyncStream<Data>
+    private let packetContinuation: AsyncStream<Data>.Continuation
+
+    // 启动函数
+    init(dnsServerAddress: SocketAddress, logger: SDLLogger) async throws {
+        self.dnsServerAddress = dnsServerAddress
+        self.logger = logger
+        
+        (self.packetFlow, self.packetContinuation) = AsyncStream.makeStream(of: Data.self, bufferingPolicy: .unbounded)
+        
+        let bootstrap = DatagramBootstrap(group: group)
+            .channelOption(ChannelOptions.socketOption(.so_reuseaddr), value: 1)
+        
+        self.asyncChannel = try await bootstrap.bind(host: "0.0.0.0", port: 0)
+            .flatMapThrowing { channel in
+                return try NIOAsyncChannel(wrappingChannelSynchronously: channel, configuration: .init(
+                    inboundType: AddressedEnvelope<ByteBuffer>.self,
+                    outboundType: AddressedEnvelope<ByteBuffer>.self
+                ))
+            }
+            .get()
+    }
+    
+    func start() async throws {
+        try await withTaskCancellationHandler {
+            try await self.asyncChannel.executeThenClose {inbound, outbound in
+                try await withThrowingTaskGroup(of: Void.self) { group in
+                    group.addTask {
+                        defer {
+                            self.logger.log("[DNSClient] inbound closed", level: .warning)
+                        }
+                        
+                        for try await envelope in inbound {
+                            try Task.checkCancellation()
+                            var buffer = envelope.data
+                            let remoteAddress = envelope.remoteAddress
+                            self.logger.log("[DNSClient] read data: \(buffer), from: \(remoteAddress)", level: .debug)
+                            
+                            let len = buffer.readableBytes
+                            if let bytes = buffer.readBytes(length: len) {
+                                self.packetContinuation.yield(Data(bytes))
+                            }
+                        }
+                    }
+                    
+                    group.addTask {
+                        defer {
+                            self.logger.log("[DNSClient] outbound closed", level: .warning)
+                        }
+                        
+                        for await message in self.writeStream {
+                            try Task.checkCancellation()
+                            
+                            let buffer = self.asyncChannel.channel.allocator.buffer(bytes: message)
+                            let envelope = AddressedEnvelope<ByteBuffer>(remoteAddress: self.dnsServerAddress, data: buffer)
+                            try await outbound.write(envelope)
+                        }
+                    }
+                    
+                    if let _ = try await group.next() {
+                        group.cancelAll()
+                    }
+                }
+            }
+        } onCancel: {
+            self.writeContinuation.finish()
+            self.packetContinuation.finish()
+            self.logger.log("[DNSClient] withTaskCancellationHandler cancel")
+        }
+    }
+    
+    func forward(ipPacket: IPPacket) {
+        self.writeContinuation.yield(ipPacket.data)
+    }
+    
+    deinit {
+        try? self.group.syncShutdownGracefully()
+        self.writeContinuation.finish()
+    }
+    
+}

Tun/Punchnet/DNSUtil.swift

@@ -1,23 +1,23 @@
-////
-////  DNSUtil.swift
-////  punchnet
-////
-////  Created by 安礼成 on 2025/12/9.
-////
 //
-//import Foundation
+//  DNSUtil.swift
-//import Network
+//  punchnet
 //
-//struct DNSUtil {
+//  Created by 安礼成 on 2025/12/9.
-//    static let dnsServers: [String] = ["100.100.100.100"]
-//    // dns请求包的目标地址
-//    static let dnsDestIpAddr: UInt32 = 1684300900
-//    
-//    // 判断是否是dns请求的数据包
-//    static func isDnsRequestPacket(ipPacket: IPPacket) -> Bool {
-//        return ipPacket.header.destination == dnsDestIpAddr
-//    }
 //
+
+import Foundation
+import Network
+
+struct DNSUtil {
+    static let dnsServers: [String] = ["100.100.100.100"]
+    // dns请求包的目标地址
+    static let dnsDestIpAddr: UInt32 = 1684300900
+    
+    // 判断是否是dns请求的数据包
+    static func isDnsRequestPacket(ipPacket: IPPacket) -> Bool {
+        return ipPacket.header.destination == dnsDestIpAddr
+    }
+    
 //    // DNS Header 结构
 //    struct DNSHeader {
 //        var id: UInt16
@@ -35,8 +35,6 @@
 //        var qclass: UInt16
 //    }
 //
-//    
-//
 //    // 解析域名（DNS Label 格式）
 //    func parseName(from data: Data, offset: inout Int) -> String {
 //        var labels: [String] = []
@@ -109,13 +107,13 @@
 //            print("Question: \(q.name), type: \(q.type), class: \(q.qclass)")
 //        }
 //    }
-//    
+    
-//}
+}
-//
+
-//// Helper 扩展：读取整数类型
+// Helper 扩展：读取整数类型
-//private extension Data {
+private extension Data {
-//    func uint16(at offset: Int) -> UInt16 {
+    func uint16(at offset: Int) -> UInt16 {
-//        let subdata = self[offset..<offset+2]
+        let subdata = self[offset..<offset+2]
-//        return subdata.withUnsafeBytes { $0.load(as: UInt16.self).bigEndian }
+        return subdata.withUnsafeBytes { $0.load(as: UInt16.self).bigEndian }
-//    }
+    }
-//}
+}

Tun/Punchnet/SDLContext.swift

@@ -51,6 +51,9 @@ public class SDLContext: @unchecked Sendable {
     var udpHole: SDLUDPHole?
     var superClient: SDLSuperClient?
     
+    // dns的client对象
+    var dnsClient: DNSClient?
+    
     // 数据包读取任务
     private var readTask: Task<(), Never>?
     
@@ -107,6 +110,18 @@ public class SDLContext: @unchecked Sendable {
     public func start() async throws {
         self.rootTask = Task {
             try await withThrowingTaskGroup(of: Void.self) { group in
+                
+                group.addTask {
+                    while !Task.isCancelled {
+                        do {
+                            try await self.startDnsClient()
+                        } catch let err {
+                            self.logger.log("[SDLContext] UDPHole get err: \(err)", level: .warning)
+                            try await Task.sleep(for: .seconds(2))
+                        }
+                    }
+                }
+                
                 group.addTask {
                     while !Task.isCancelled {
                         do {
@@ -235,6 +250,35 @@ public class SDLContext: @unchecked Sendable {
         }
     }
     
+    private func startDnsClient() async throws {
+        let dnsSocketAddress = try SocketAddress.makeAddressResolvingHost("127.0.0.1", port: 15353)
+        self.dnsClient = try await DNSClient(dnsServerAddress: dnsSocketAddress, logger: self.logger)
+        
+        try await withThrowingTaskGroup(of: Void.self) { group in
+            defer {
+                self.logger.log("[SDLContext] dns client task cancel", level: .warning)
+            }
+            
+            group.addTask {
+                try await self.dnsClient?.start()
+            }
+            
+            group.addTask {
+                if let packetFlow = self.dnsClient?.packetFlow {
+                    for await packet in packetFlow {
+                        let nePacket = NEPacket(data: packet, protocolFamily: 2)
+                        self.provider.packetFlow.writePacketObjects([nePacket])
+                    }
+                }
+                
+            }
+            
+            if let _ = try await group.next() {
+                group.cancelAll()
+            }
+        }
+    }
+    
     private func handleSuperEvent(event: SDLSuperClient.SuperEvent) async throws {
         switch event {
         case .ready:
@@ -485,39 +529,47 @@ public class SDLContext: @unchecked Sendable {
             repeat {
                 let (packets, numbers) = await self.provider.packetFlow.readPackets()
                 for (data, number) in zip(packets, numbers) where number == 2 {
-                    if let packet = IPPacket(data) {
+                    await self.dealPacket(data: data)
-                        let destIp = packet.header.destination_ip
-                        NSLog("destIp: \(destIp), int: \(packet.header.destination)")
-                        
-                        
-                        Task.detached {
-                            let dstIp = packet.header.destination
-                            // 本地通讯, 目标地址是本地服务器的ip地址
-                            if dstIp == self.devAddr.netAddr {
-                                let nePacket = NEPacket(data: packet.data, protocolFamily: 2)
-                                self.provider.packetFlow.writePacketObjects([nePacket])
-                                return
-                            }
-                            
-                            // 查找arp缓存中是否有目标mac地址
-                            if let dstMac = await self.arpServer.query(ip: dstIp) {
-                                await self.routeLayerPacket(dstMac: dstMac, type: .ipv4, data: packet.data)
-                            }
-                            else {
-                                // 构造arp请求
-                                let broadcastMac = Data([0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF])
-                                let arpReqeust = ARPPacket.arpRequest(senderIP: self.devAddr.netAddr, senderMAC: self.devAddr.mac, targetIP: dstIp)
-                                await self.routeLayerPacket(dstMac: broadcastMac, type: .arp, data: arpReqeust.marshal())
-                                
-                                self.logger.log("[SDLContext] dstIp: \(dstIp) arp query not found", level: .debug)
-                            }
-                        }
-                    }
                 }
-                
             } while true
         }
+    }
     
+    // 处理读取的每个数据包
+    private func dealPacket(data: Data) async {
+        guard let packet = IPPacket(data) else {
+            return
+        }
+        
+        if DNSUtil.isDnsRequestPacket(ipPacket: packet) {
+            let destIp = packet.header.destination_ip
+            NSLog("destIp: \(destIp), int: \(packet.header.destination)")
+            await self.dnsClient?.forward(ipPacket: packet)
+        }
+        else {
+            Task.detached {
+                let dstIp = packet.header.destination
+                // 本地通讯, 目标地址是本地服务器的ip地址
+                if dstIp == self.devAddr.netAddr {
+                    let nePacket = NEPacket(data: packet.data, protocolFamily: 2)
+                    self.provider.packetFlow.writePacketObjects([nePacket])
+                    return
+                }
+                
+                // 查找arp缓存中是否有目标mac地址
+                if let dstMac = await self.arpServer.query(ip: dstIp) {
+                    await self.routeLayerPacket(dstMac: dstMac, type: .ipv4, data: packet.data)
+                }
+                else {
+                    // 构造arp请求
+                    let broadcastMac = Data([0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF])
+                    let arpReqeust = ARPPacket.arpRequest(senderIP: self.devAddr.netAddr, senderMAC: self.devAddr.mac, targetIP: dstIp)
+                    await self.routeLayerPacket(dstMac: broadcastMac, type: .arp, data: arpReqeust.marshal())
+                    
+                    self.logger.log("[SDLContext] dstIp: \(dstIp) arp query not found", level: .debug)
+                }
+            }
+        }
     }
     
     private func routeLayerPacket(dstMac: Data, type: LayerPacket.PacketType, data: Data) async {
@@ -594,6 +646,7 @@ public class SDLContext: @unchecked Sendable {
         self.rootTask?.cancel()
         self.udpHole = nil
         self.superClient = nil
+        self.dnsClient = nil
     }
     
     // 获取mac地址