rebrand: frp -> kanhole (kanhole server, kanholec client)

cmd/kanholec/sub/nathole.go

@@ -0,0 +1,100 @@
+// Copyright 2023 The kanhole Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package sub
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+
+	"kanhole/pkg/config"
+	v1 "kanhole/pkg/config/v1"
+	"kanhole/pkg/nathole"
+)
+
+var (
+	natHoleSTUNServer string
+	natHoleLocalAddr  string
+)
+
+func init() {
+	rootCmd.AddCommand(natholeCmd)
+	natholeCmd.AddCommand(natholeDiscoveryCmd)
+
+	natholeCmd.PersistentFlags().StringVarP(&natHoleSTUNServer, "nat_hole_stun_server", "", "", "STUN server address for nathole")
+	natholeCmd.PersistentFlags().StringVarP(&natHoleLocalAddr, "nat_hole_local_addr", "l", "", "local address to connect STUN server")
+}
+
+var natholeCmd = &cobra.Command{
+	Use:   "nathole",
+	Short: "Actions about nathole",
+}
+
+var natholeDiscoveryCmd = &cobra.Command{
+	Use:   "discover",
+	Short: "Discover nathole information from stun server",
+	RunE: func(cmd *cobra.Command, args []string) error {
+		// ignore error here, because we can use command line parameters
+		cfg, _, _, _, err := config.LoadClientConfig(cfgFile, strictConfigMode)
+		if err != nil {
+			cfg = &v1.ClientCommonConfig{}
+			if err := cfg.Complete(); err != nil {
+				fmt.Printf("failed to complete config: %v\n", err)
+				os.Exit(1)
+			}
+		}
+		if natHoleSTUNServer != "" {
+			cfg.NatHoleSTUNServer = natHoleSTUNServer
+		}
+
+		if err := validateForNatHoleDiscovery(cfg); err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+
+		addrs, localAddr, err := nathole.Discover([]string{cfg.NatHoleSTUNServer}, natHoleLocalAddr)
+		if err != nil {
+			fmt.Println("discover error:", err)
+			os.Exit(1)
+		}
+		if len(addrs) < 2 {
+			fmt.Printf("discover error: can not get enough addresses, need 2, got: %v\n", addrs)
+			os.Exit(1)
+		}
+
+		localIPs, _ := nathole.ListLocalIPsForNatHole(10)
+
+		natFeature, err := nathole.ClassifyNATFeature(addrs, localIPs)
+		if err != nil {
+			fmt.Println("classify nat feature error:", err)
+			os.Exit(1)
+		}
+		fmt.Println("STUN server:", cfg.NatHoleSTUNServer)
+		fmt.Println("Your NAT type is:", natFeature.NatType)
+		fmt.Println("Behavior is:", natFeature.Behavior)
+		fmt.Println("External address is:", addrs)
+		fmt.Println("Local address is:", localAddr.String())
+		fmt.Println("Public Network:", natFeature.PublicNetwork)
+		return nil
+	},
+}
+
+func validateForNatHoleDiscovery(cfg *v1.ClientCommonConfig) error {
+	if cfg.NatHoleSTUNServer == "" {
+		return fmt.Errorf("nat_hole_stun_server can not be empty")
+	}
+	return nil
+}