Default to tcp-tls for upstream

1 files changed, 14 insertions, 10 deletions

diff --git a/dns/proxy.go b/dns/proxy.go
index 4779b66..3994bb8 100644
--- a/dns/proxy.go
+++ b/dns/proxy.go
@@ -1,6 +1,7 @@
 package dns
 
 import (
+	"log"
 	"net"
 	"strings"
 	"time"
@@ -28,8 +29,9 @@ type Handler func(*Request) *Reply
 
 // Proxy represents a DNS proxy.
 type Proxy struct {
-	handler   Handler
-	resolvers []string
+	Handler   Handler
+	Resolvers []string
+	logger    *log.Logger
 	server    *dns.Server
 	client    client
 }
@@ -39,11 +41,10 @@ type client interface {
 }
 
 // NewProxy creates a new DNS proxy.
-func NewProxy(handler Handler, resolvers []string, timeout time.Duration) *Proxy {
+func NewProxy(logger *log.Logger, network string, timeout time.Duration) *Proxy {
 	return &Proxy{
-		handler:   handler,
-		resolvers: resolvers,
-		client:    &dns.Client{Timeout: timeout},
+		logger: logger,
+		client: &dns.Client{Net: network, Timeout: timeout},
 	}
 }
 
@@ -83,10 +84,10 @@ func (r *Reply) String() string {
 }
 
 func (p *Proxy) reply(r *dns.Msg) *dns.Msg {
-	if p.handler == nil || len(r.Question) != 1 {
+	if p.Handler == nil || len(r.Question) != 1 {
 		return nil
 	}
-	reply := p.handler(&Request{
+	reply := p.Handler(&Request{
 		Name: r.Question[0].Name,
 		Type: r.Question[0].Qtype,
 	})
@@ -115,10 +116,13 @@ func (p *Proxy) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 		_ = w.WriteMsg(reply) // TODO: Decide whether to handle write errors
 		return
 	}
-	for i, resolver := range p.resolvers {
+	for i, resolver := range p.Resolvers {
 		rr, _, err := p.client.Exchange(r, resolver)
 		if err != nil {
-			if i == len(p.resolvers)-1 {
+			if p.logger != nil {
+				p.logger.Printf("resolver %s failed: %s", resolver, err)
+			}
+			if i == len(p.Resolvers)-1 {
 				break
 			} else {
 				continue