Add secret generator

cmd/generate-mtproto-secret/main.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"crypto/rand"
+	"os"
+
+	"github.com/sagernet/sing-box/log"
+	"github.com/sagernet/sing-box/transport/mtproto"
+
+	"github.com/spf13/cobra"
+)
+
+var mainCommand = &cobra.Command{
+	Use:  "generate-mtproto-secret <hostname>",
+	Args: cobra.ExactArgs(1),
+	Run: func(cmd *cobra.Command, args []string) {
+		err := generate(args[0])
+		if err != nil {
+			log.Fatal(err)
+		}
+	},
+}
+
+func main() {
+	if err := mainCommand.Execute(); err != nil {
+		log.Fatal(err)
+	}
+}
+
+func generate(hostname string) error {
+	secret := mtproto.Secret{
+		Host: hostname,
+	}
+	_, err := rand.Read(secret.Key[:])
+	if err != nil {
+		return err
+	}
+	_, err = os.Stdout.WriteString(secret.String() + "\n")
+	return err
+}