Make generated files have `SUDO_USER`'s permissions if possible.

cmd/sing-box/cmd_run.go

@@ -133,7 +133,7 @@ func create() (*box.Box, context.CancelFunc, error) {
 		}
 		options.Log.DisableColor = true
 	}
-	ctx, cancel := context.WithCancel(context.Background())
+	ctx, cancel := context.WithCancel(globalCtx)
 	instance, err := box.New(box.Options{
 		Context: ctx,
 		Options: options,

cmd/sing-box/main.go

@@ -3,15 +3,19 @@ package main
 import (
 	"context"
 	"os"
+	"os/user"
+	"strconv"
 	"time"
 
 	_ "github.com/sagernet/sing-box/include"
 	"github.com/sagernet/sing-box/log"
+	"github.com/sagernet/sing/service/filemanager"
 
 	"github.com/spf13/cobra"
 )
 
 var (
+	globalCtx         context.Context
 	configPaths       []string
 	configDirectories []string
 	workingDir        string
@@ -37,15 +41,30 @@ func main() {
 }
 
 func preRun(cmd *cobra.Command, args []string) {
+	globalCtx = context.Background()
+	sudoUser := os.Getenv("SUDO_USER")
+	sudoUID, _ := strconv.Atoi(os.Getenv("SUDO_UID"))
+	sudoGID, _ := strconv.Atoi(os.Getenv("SUDO_GID"))
+	if sudoUID == 0 && sudoGID == 0 && sudoUser != "" {
+		sudoUserObject, _ := user.Lookup(sudoUser)
+		if sudoUserObject != nil {
+			sudoUID, _ = strconv.Atoi(sudoUserObject.Uid)
+			sudoGID, _ = strconv.Atoi(sudoUserObject.Gid)
+		}
+	}
+	if sudoUID > 0 && sudoGID > 0 {
+		globalCtx = filemanager.WithDefault(globalCtx, "", "", sudoUID, sudoGID)
+	}
 	if disableColor {
 		log.SetStdLogger(log.NewDefaultFactory(context.Background(), log.Formatter{BaseTime: time.Now(), DisableColors: true}, os.Stderr, "", nil, false).Logger())
 	}
 	if workingDir != "" {
 		_, err := os.Stat(workingDir)
 		if err != nil {
-			os.MkdirAll(workingDir, 0o777)
+			filemanager.MkdirAll(globalCtx, workingDir, 0o777)
 		}
-		if err := os.Chdir(workingDir); err != nil {
+		err = os.Chdir(workingDir)
+		if err != nil {
 			log.Fatal(err)
 		}
 	}