From 6f3c0a126ca15bec6b0db0c77e65ed4ad2354ca2 Mon Sep 17 00:00:00 2001
From: Star Brilliant <m13253@hotmail.com>
Date: Fri, 13 Oct 2017 23:21:46 +0800
Subject: [PATCH] Fix EDNS Extended RCODE (#517)

* Fix EDNS Extended RCODE

Issue #516

* Fix EDNS Extended RCODE

Issue #516
---
 edns.go      | 7 ++-----
 edns_test.go | 2 +-
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/edns.go b/edns.go
index 718842f2..10d69f2c 100644
--- a/edns.go
+++ b/edns.go
@@ -106,15 +106,12 @@ func (rr *OPT) SetVersion(v uint8) {
 
 // ExtendedRcode returns the EDNS extended RCODE field (the upper 8 bits of the TTL).
 func (rr *OPT) ExtendedRcode() int {
-	return int((rr.Hdr.Ttl&0xFF000000)>>24) + 15
+	return int((rr.Hdr.Ttl&0xFF000000)>>24)
 }
 
 // SetExtendedRcode sets the EDNS extended RCODE field.
 func (rr *OPT) SetExtendedRcode(v uint8) {
-	if v < RcodeBadVers { // Smaller than 16.. Use the 4 bits you have!
-		return
-	}
-	rr.Hdr.Ttl = rr.Hdr.Ttl&0x00FFFFFF | (uint32(v-15) << 24)
+	rr.Hdr.Ttl = rr.Hdr.Ttl&0x00FFFFFF | (uint32(v) << 24)
 }
 
 // UDPSize returns the UDP buffer size.
diff --git a/edns_test.go b/edns_test.go
index c290b0c8..f7cf1575 100644
--- a/edns_test.go
+++ b/edns_test.go
@@ -63,6 +63,6 @@ func TestOPTTtl(t *testing.T) {
 
 	e.SetExtendedRcode(42)
 	if e.ExtendedRcode() != 42 {
-		t.Errorf("set 42, expected %d, got %d", 42-15, e.ExtendedRcode())
+		t.Errorf("set 42, expected %d, got %d", 42, e.ExtendedRcode())
 	}
 }