From 2e6cd26cecb7e2ea53db8aefa840f5a04bcfc0d1 Mon Sep 17 00:00:00 2001
From: Yiyang Kang <kkyy@kkyy.me>
Date: Wed, 23 Nov 2022 05:09:54 +0800
Subject: [PATCH] fix: domain name validation

hopefully
---
 cmds/dig.go | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/cmds/dig.go b/cmds/dig.go
index e61c1ab..c168b56 100644
--- a/cmds/dig.go
+++ b/cmds/dig.go
@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"github.com/go-errors/errors"
+	"golang.org/x/net/idna"
 
 	"git.gensokyo.cafe/kkyy/tgbot_misaka_5882f7/utils"
 )
@@ -27,7 +28,7 @@ var (
 
 	digErrInvalidArgs = fmt.Errorf("invalid request")
 
-	digDnsNameRe = regexp.MustCompile(`^([a-z0-9_-]+\.?)+|\.$`)
+	digIdnaMapper = idna.New(idna.MapForLookup(), idna.StrictDomainName(false))
 )
 
 type DigRequest struct {
@@ -61,8 +62,8 @@ func NewDigRequest(req string) (*DigRequest, error) {
 		return ret, nil
 	}
 
-	name := strings.ToLower(args[0])
-	if !digDnsNameRe.Match([]byte(name)) {
+	name, err := digIdnaMapper.ToASCII(args[0])
+	if err != nil {
 		return nil, digErrInvalidArgs
 	}
 	ret.Name = name