EtherGuard-VPN/main.go
2018-02-04 16:08:26 +01:00

197 lines
3.3 KiB
Go

package main
import (
"fmt"
"os"
"os/signal"
"runtime"
"strconv"
)
const (
ExitSetupSuccess = 0
ExitSetupFailed = 1
)
const (
ENV_WG_TUN_FD = "WG_TUN_FD"
ENV_WG_UAPI_FD = "WG_UAPI_FD"
)
func printUsage() {
fmt.Printf("usage:\n")
fmt.Printf("%s [-f/--foreground] INTERFACE-NAME\n", os.Args[0])
}
func main() {
// parse arguments
var foreground bool
var interfaceName string
if len(os.Args) < 2 || len(os.Args) > 3 {
printUsage()
return
}
switch os.Args[1] {
case "-f", "--foreground":
foreground = true
if len(os.Args) != 3 {
printUsage()
return
}
interfaceName = os.Args[2]
default:
foreground = false
if len(os.Args) != 2 {
printUsage()
return
}
interfaceName = os.Args[1]
}
// get log level (default: info)
logLevel := func() int {
switch os.Getenv("LOG_LEVEL") {
case "debug":
return LogLevelDebug
case "info":
return LogLevelInfo
case "error":
return LogLevelError
}
return LogLevelInfo
}()
logger := NewLogger(
logLevel,
fmt.Sprintf("(%s) ", interfaceName),
)
logger.Debug.Println("Debug log enabled")
// open TUN device (or use supplied fd)
tun, err := func() (TUNDevice, error) {
tunFdStr := os.Getenv(ENV_WG_TUN_FD)
if tunFdStr == "" {
return CreateTUN(interfaceName)
}
// construct tun device from supplied fd
fd, err := strconv.ParseUint(tunFdStr, 10, 32)
if err != nil {
return nil, err
}
file := os.NewFile(uintptr(fd), "")
return CreateTUNFromFile(interfaceName, file)
}()
if err != nil {
logger.Error.Println("Failed to create TUN device:", err)
os.Exit(ExitSetupFailed)
}
// open UAPI file (or use supplied fd)
fileUAPI, err := func() (*os.File, error) {
uapiFdStr := os.Getenv(ENV_WG_UAPI_FD)
if uapiFdStr == "" {
return UAPIOpen(interfaceName)
}
// use supplied fd
fd, err := strconv.ParseUint(uapiFdStr, 10, 32)
if err != nil {
return nil, err
}
return os.NewFile(uintptr(fd), ""), nil
}()
if err != nil {
logger.Error.Println("UAPI listen error:", err)
os.Exit(ExitSetupFailed)
return
}
// daemonize the process
if !foreground {
env := os.Environ()
env = append(env, fmt.Sprintf("%s=3", ENV_WG_TUN_FD))
env = append(env, fmt.Sprintf("%s=4", ENV_WG_UAPI_FD))
attr := &os.ProcAttr{
Files: []*os.File{
nil, // stdin
nil, // stdout
nil, // stderr
tun.File(),
fileUAPI,
},
Dir: ".",
Env: env,
}
err = Daemonize(attr)
if err != nil {
logger.Error.Println("Failed to daemonize:", err)
os.Exit(ExitSetupFailed)
}
return
}
// increase number of go workers (for Go <1.5)
runtime.GOMAXPROCS(runtime.NumCPU())
// create wireguard device
device := NewDevice(tun, logger)
logger.Info.Println("Device started")
// start uapi listener
errs := make(chan error)
term := make(chan os.Signal)
uapi, err := UAPIListen(interfaceName, fileUAPI)
go func() {
for {
conn, err := uapi.Accept()
if err != nil {
errs <- err
return
}
go ipcHandle(device, conn)
}
}()
logger.Info.Println("UAPI listener started")
// wait for program to terminate
signal.Notify(term, os.Kill)
signal.Notify(term, os.Interrupt)
select {
case <-term:
case <-errs:
case <-device.Wait():
}
// clean up
uapi.Close()
device.Close()
logger.Info.Println("Shutting down")
}