Merge branch 'modular'

README.md

@@ -1,14 +1,13 @@
 # dingo
-
-A DNS client in Go that supports the [Google
+A DNS client (stub resolver) implemented in Go for the [Google
 DNS-over-HTTPS](https://developers.google.com/speed/public-dns/docs/dns-over-https).
 It effectively encrypts all your DNS traffic. It also supports
 [OpenResolve](https://www.openresolve.com/) by OpenDNS.
 
-The ultimate goal for the project is to provide a secure, caching DNS proxy that
+The ultimate goal for the project is to provide a secure, caching DNS client that
 communicates with recursive DNS resolvers over encrypted channels only. For now,
-it resolves DNS queries over HTTPS/1.1 in independent threads. The plans for
-future include better caching and support for HTTP/2.0 and QUIC.
+it resolves DNS queries over HTTP/2 in independent threads. The plans for
+future include better caching and support for QUIC.
 
 ## Quick start
 
@@ -63,6 +62,8 @@ Usage of dingo-linux-amd64:
     	Google DNS: SNI string to send (should match server certificate) (default "www.google.com")
   -gdns:workers int
     	Google DNS: number of independent workers (default 10)
+  -h1
+    	use HTTPS/1.1 transport
   -odns:host string
     	OpenDNS: HTTP 'Host' header (real FQDN, encrypted in TLS) (default "api.openresolve.com")
   -odns:server string

dingo.go

@@ -23,15 +23,16 @@ import "math/rand"
 
 /* command-line arguments */
 var (
-	bindip  = flag.String("bind", "127.0.0.1", "IP address to bind to")
-	port    = flag.Int("port", 32000, "listen on port number")
-	dbglvl  = flag.Int("dbg", 2, "debugging level")
+	opt_bindip  = flag.String("bind", "127.0.0.1", "IP address to bind to")
+	opt_port    = flag.Int("port", 32000, "listen on port number")
+	opt_h1      = flag.Bool("h1", false, "use HTTPS/1.1 transport")
+	opt_dbglvl  = flag.Int("dbg", 2, "debugging level")
 )
 
 /**********************************************************************/
 
 /* logging stuff */
-func dbg(lvl int, fmt string, v ...interface{}) { if (*dbglvl >= lvl) { dbglog.Printf(fmt, v...) } }
+func dbg(lvl int, fmt string, v ...interface{}) { if (*opt_dbglvl >= lvl) { dbglog.Printf(fmt, v...) } }
 func die(msg error) { dbglog.Fatalln("fatal error:", msg.Error()) }
 var dbglog *log.Logger
 
@@ -165,15 +166,15 @@ func main() {
 	rcache = cache.New(24*time.Hour, 60*time.Second)
 
 	/* listen */
-	laddr   := net.UDPAddr{ IP: net.ParseIP(*bindip), Port: *port }
+	laddr   := net.UDPAddr{ IP: net.ParseIP(*opt_bindip), Port: *opt_port }
 	uc, err := net.ListenUDP("udp", &laddr)
 	if err != nil { die(err) }
 
 	/* start workers */
 	for _, mod := range Modules { mod.Start() }
 
 	/* accept new connections forever */
-	dbg(1, "dingo ver. 0.12 listening on %s UDP port %d", *bindip, laddr.Port)
+	dbg(1, "dingo ver. 0.13 listening on %s UDP port %d", *opt_bindip, laddr.Port)
 	var buf []byte
 	for {
 		buf = make([]byte, 1500)

gdns.go

@@ -64,7 +64,9 @@ func (R *Gdns) Start() {
 
 func (R *Gdns) worker(server string) {
 	var https = NewHttps(*R.sni)
-	for q := range qchan { *q.rchan <- *R.resolve(https, server, q.Name, q.Type) }
+	for q := range qchan {
+		*q.rchan <- *R.resolve(https, server, q.Name, q.Type)
+	}
 }
 
 func (R *Gdns) resolve(https *Https, server string, qname string, qtype int) *Reply {

https.go

@@ -13,21 +13,34 @@ import "net/http"
 import "io/ioutil"
 import "crypto/tls"
 import "errors"
+import "golang.org/x/net/http2"
 
 type Https struct {
-	client    http.Client
-	transport http.Transport
-	tlscfg    tls.Config
+	client     http.Client
 }
 
 func NewHttps(sni string) *Https {
 	H := Https{}
 
-	/* basic setup */
+	/* TLS setup */
+	tlscfg := new(tls.Config)
+	tlscfg.ServerName = sni
+
+	/* HTTP transport */
+	var tr http.RoundTripper
+	if (*opt_h1) {
+		h1 := new(http.Transport)
+		h1.TLSClientConfig = tlscfg
+		tr = h1
+	} else {
+		h2 := new(http2.Transport)
+		h2.TLSClientConfig = tlscfg
+		tr = h2
+	}
+
+	/* HTTP client */
 	H.client.Timeout = time.Second * 10
-	H.client.Transport = &H.transport
-	H.transport.TLSClientConfig = &H.tlscfg
-	H.tlscfg.ServerName = sni
+	H.client.Transport = tr
 
 	return &H
 }