From c2280555d34c795f95e1e5ce155508d35ddc5db9 Mon Sep 17 00:00:00 2001
From: Kr328 <39107975+Kr328@users.noreply.github.com>
Date: Tue, 14 Apr 2020 02:17:07 +0800
Subject: [PATCH] fix dns hijacking

---
 core/src/main/golang/tun/dns.go | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/core/src/main/golang/tun/dns.go b/core/src/main/golang/tun/dns.go
index a73320e..4b1a8f7 100644
--- a/core/src/main/golang/tun/dns.go
+++ b/core/src/main/golang/tun/dns.go
@@ -35,13 +35,11 @@ func InitialResolver() {
 
 	rawResolver := resolver.DefaultResolver
 	if rawResolver == nil {
-		hijackAddress = nil
 		dnsHandler = nil
 		return
 	}
 	r, ok := rawResolver.(*dns.Resolver)
 	if !ok || r == nil {
-		hijackAddress = nil
 		dnsHandler = nil
 		return
 	}
@@ -54,6 +52,10 @@ func hijackTCPDNS(conn net.Conn, endpoint *binding.Endpoint) bool {
 		return false
 	}
 
+	if dnsHandler == nil {
+		return false
+	}
+
 	if !hijackAddress.Equal(net.IPv4zero) && !hijackAddress.Equal(net.IPv6zero) && !hijackAddress.Equal(endpoint.Target.IP) {
 		return false
 	}
@@ -103,6 +105,10 @@ func hijackDNS(payload []byte, endpoint *binding.Endpoint, sender redirect.UDPSe
 		return false
 	}
 
+	if dnsHandler == nil {
+		return false
+	}
+
 	if !hijackAddress.Equal(net.IPv4zero) && !hijackAddress.Equal(net.IPv6zero) && !hijackAddress.Equal(endpoint.Target.IP) {
 		return false
 	}