SoftEther Wrapper

main.go

package main

import (
    "flag"
    "fmt"
    "log"
    "os"
    "os/exec"
    "strings"
    "net"
)

func main(){
    flag.Parse()
    if flag.Arg(0) == "" {
        fmt.Println("Specify Connection Name")
        os.Exit(1)
    }
    out, err := exec.Command("vpncmd", "/client", "localhost", "/cmd", "AccountGet", flag.Arg(0)).Output()
    if err != nil {
        fmt.Printf("接続 %v は存在しません\n", flag.Arg(0))
        log.Fatal(err)
    }
    out_list := strings.Split(string(out), "\n")
    var server_address string = ""
    for i := 0; i < len(out_list); i++ {
        if strings.Index(out_list[i], "VPN Client>AccountGet") != -1 {
            server_address = out_list[i+5]
            break
        }
    }
    server_address = strings.Split(server_address, "|")[1]
    if net.ParseIP(server_address) != nil {
        fmt.Println("IP")
    } else {
        addr, err := net.ResolveIPAddr("ip", server_address)
        if err != nil {
            fmt.Println("Resolve error")
            os.Exit(1)
        }
        fmt.Printf("VPN Server URI: %v\n", server_address)
        server_address = addr.String()
    }
    fmt.Printf("VPN Server IP : %v\n", server_address)

    _ = exec.Command("ip", "route", "del", server_address).Run()
    _ = exec.Command("dhcpcd", "-x", "vpn_"+strings.ToLower(flag.Arg(0))).Run()

    out, err = exec.Command("sh", "-c", "ip route | grep default").Output()
    if err != nil {
        fmt.Println("Failed to exec ip route")
        log.Fatal(err)
        os.Exit(1)
    }
    if len(out) < 1 {
        fmt.Println("Failed to get default gateway")
        os.Exit(1)
    }
    gateway_string := strings.Split(string(out), "\n")[0]
    gateway_ip := strings.Split(string(gateway_string), " ")[2]
    gateway_dev := strings.Split(string(gateway_string), " ")[4]
    fmt.Printf("Default Gateway IP : %v\n", gateway_ip)
    fmt.Printf("Default Gateway Dev: %v\n", gateway_dev)
    fmt.Printf("Adding VPN Server Route...\n")
    out, err = exec.Command("ip", "route", "add", server_address, "via", gateway_ip, "dev", gateway_dev).Output()
    if err != nil {
        fmt.Println("Failed to exec ip route")
        log.Fatal(err)
        os.Exit(1)
    }
    fmt.Printf("Successfully Added VPN Server Route\n")
    out, err = exec.Command("vpncmd", "/client", "localhost", "/cmd", "AccountConnect", flag.Arg(0)).Output()
    if err != nil {
        fmt.Printf("Failed to Connect\n", flag.Arg(0))
        log.Fatal(err)
    }
}