From 10c9ccba538c8670793e04ee593fddd30f3bc50b Mon Sep 17 00:00:00 2001
From: Lev Lybin <lev.lybin@gmail.com>
Date: Fri, 19 Jul 2019 20:51:37 +0700
Subject: [PATCH] answer only with requested type

---
 burst/blockchain.go |  2 +-
 dns/dns.go          |  8 ++++++--
 dns/resourse.go     | 13 ++++++++++++-
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/burst/blockchain.go b/burst/blockchain.go
index 2c9bc0c..a1488de 100644
--- a/burst/blockchain.go
+++ b/burst/blockchain.go
@@ -23,7 +23,7 @@ type response struct {
 	Alias     string
 }
 
-var httpClient = &http.Client{Timeout: 5 * time.Second}
+var httpClient = &http.Client{Timeout: 10 * time.Second}
 
 func getJson(url string, target interface{}) error {
 	r, err := httpClient.Get(url)
diff --git a/dns/dns.go b/dns/dns.go
index c0f1d86..e231f39 100644
--- a/dns/dns.go
+++ b/dns/dns.go
@@ -50,6 +50,10 @@ func (s *BurstDNS) answer(addr net.UDPAddr, m dnsmessage.Message) {
 
 	if records, err := burst.GetRecords(aliasName); err == nil {
 		for _, record := range records {
+			// return only requested type
+			if record.Type != dnsTypeToStr(m.Questions[0].Type) {
+				continue
+			}
 			req := request{
 				Host: domain,
 				Type: record.Type,
@@ -57,7 +61,7 @@ func (s *BurstDNS) answer(addr net.UDPAddr, m dnsmessage.Message) {
 				TTL:  record.TTL,
 			}
 
-			res, err := ToResource(req)
+			res, err := toResource(req)
 			if err != nil {
 				log.Println(err)
 				continue
@@ -108,7 +112,7 @@ func (s *BurstDNS) Listen() {
 			continue
 		}
 
-		log.Printf("Got request %v, %v from: %s\n", m, m.Header, addr)
+		//log.Printf("Got request %v, %v from: %s\n", m, m.Header, addr)
 
 		go s.answer(*addr, m)
 	}
diff --git a/dns/resourse.go b/dns/resourse.go
index f415e72..7fc7257 100644
--- a/dns/resourse.go
+++ b/dns/resourse.go
@@ -11,7 +11,7 @@ var (
 	errUnknownType = errors.New("type unknown")
 )
 
-func ToResource(req request) (dnsmessage.Resource, error) {
+func toResource(req request) (dnsmessage.Resource, error) {
 	rName, err := dnsmessage.NewName(req.Host)
 	none := dnsmessage.Resource{}
 	if err != nil {
@@ -52,3 +52,14 @@ func ToResource(req request) (dnsmessage.Resource, error) {
 		Body: rBody,
 	}, nil
 }
+
+func dnsTypeToStr(dnsType dnsmessage.Type) string {
+	switch dnsType {
+	case dnsmessage.TypeA:
+		return "a"
+	case dnsmessage.TypeAAAA:
+		return "aaaa"
+	default:
+		return ""
+	}
+}