From 756c932e372e36b5a6814d73fa6dac6c8799c9a1 Mon Sep 17 00:00:00 2001
From: Dimitry Kolyshev <dkolyshev@adguard.com>
Date: Thu, 26 May 2022 17:53:11 +0300
Subject: [PATCH] Pull request: dnsforward: add doq alpn

Merge in DNS/adguard-home from 4592-doq-alpn to master

Squashed commit of the following:

commit 5985445dbf5158ae1e5b0235b404dd188c856e60
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Thu May 26 16:42:06 2022 +0200

    dnsforward: add doq alpn

commit 9dcd6fee615a1a5ac1f80641ac16c18371b67096
Merge: 2564c870 c3d5fcc6
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Thu May 26 15:24:07 2022 +0200

    Merge remote-tracking branch 'origin/master' into 4592-doq-alpn

commit 2564c870e704ff453d0ad2fb22fa295ef725dd13
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Thu May 26 15:20:16 2022 +0200

    dnsforward: add doq alpn
---
 internal/dnsforward/dns.go      | 21 ++++++++++++++++++---
 internal/dnsforward/dns_test.go | 26 ++++++++++++++++++++++++--
 2 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/internal/dnsforward/dns.go b/internal/dnsforward/dns.go
index 19d54d91..e049bef0 100644
--- a/internal/dnsforward/dns.go
+++ b/internal/dnsforward/dns.go
@@ -260,9 +260,8 @@ func (s *Server) processDDRQuery(ctx *dnsContext) (rc resultCode) {
 	}
 
 	if question.Name == ddrHostFQDN {
-		// TODO(a.garipov): Check DoQ support in next RFC drafts.
-		if s.dnsProxy.TLSListenAddr == nil && s.dnsProxy.HTTPSListenAddr == nil ||
-			question.Qtype != dns.TypeSVCB {
+		if s.dnsProxy.TLSListenAddr == nil && s.dnsProxy.HTTPSListenAddr == nil &&
+			s.dnsProxy.QUICListenAddr == nil || question.Qtype != dns.TypeSVCB {
 			d.Res = s.makeResponse(d.Req)
 
 			return resultCodeFinish
@@ -314,6 +313,22 @@ func (s *Server) makeDDRResponse(req *dns.Msg) (resp *dns.Msg) {
 		resp.Answer = append(resp.Answer, ans)
 	}
 
+	for _, addr := range s.dnsProxy.QUICListenAddr {
+		values := []dns.SVCBKeyValue{
+			&dns.SVCBAlpn{Alpn: []string{"doq"}},
+			&dns.SVCBPort{Port: uint16(addr.Port)},
+		}
+
+		ans := &dns.SVCB{
+			Hdr:      s.hdr(req, dns.TypeSVCB),
+			Priority: 3,
+			Target:   domainName,
+			Value:    values,
+		}
+
+		resp.Answer = append(resp.Answer, ans)
+	}
+
 	return resp
 }
 
diff --git a/internal/dnsforward/dns_test.go b/internal/dnsforward/dns_test.go
index 8ab7501c..b40b7bc2 100644
--- a/internal/dnsforward/dns_test.go
+++ b/internal/dnsforward/dns_test.go
@@ -36,6 +36,15 @@ func TestServer_ProcessDDRQuery(t *testing.T) {
 		},
 	}
 
+	doqSVCB := &dns.SVCB{
+		Priority: 3,
+		Target:   ddrTestDomainName,
+		Value: []dns.SVCBKeyValue{
+			&dns.SVCBAlpn{Alpn: []string{"doq"}},
+			&dns.SVCBPort{Port: 8042},
+		},
+	}
+
 	testCases := []struct {
 		name       string
 		host       string
@@ -43,6 +52,7 @@ func TestServer_ProcessDDRQuery(t *testing.T) {
 		wantRes    resultCode
 		portDoH    int
 		portDoT    int
+		portDoQ    int
 		qtype      uint16
 		ddrEnabled bool
 	}{{
@@ -88,6 +98,14 @@ func TestServer_ProcessDDRQuery(t *testing.T) {
 		qtype:      dns.TypeSVCB,
 		ddrEnabled: true,
 		portDoH:    8044,
+	}, {
+		name:       "doq",
+		wantRes:    resultCodeFinish,
+		want:       []*dns.SVCB{doqSVCB},
+		host:       ddrHostFQDN,
+		qtype:      dns.TypeSVCB,
+		ddrEnabled: true,
+		portDoQ:    8042,
 	}, {
 		name:       "dot_doh",
 		wantRes:    resultCodeFinish,
@@ -101,7 +119,7 @@ func TestServer_ProcessDDRQuery(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			s := prepareTestServer(t, tc.portDoH, tc.portDoT, tc.ddrEnabled)
+			s := prepareTestServer(t, tc.portDoH, tc.portDoT, tc.portDoQ, tc.ddrEnabled)
 
 			req := createTestMessageWithType(tc.host, tc.qtype)
 
@@ -130,7 +148,7 @@ func TestServer_ProcessDDRQuery(t *testing.T) {
 	}
 }
 
-func prepareTestServer(t *testing.T, portDoH, portDoT int, ddrEnabled bool) (s *Server) {
+func prepareTestServer(t *testing.T, portDoH, portDoT, portDoQ int, ddrEnabled bool) (s *Server) {
 	t.Helper()
 
 	proxyConf := proxy.Config{}
@@ -143,6 +161,10 @@ func prepareTestServer(t *testing.T, portDoH, portDoT int, ddrEnabled bool) (s *
 		proxyConf.TLSListenAddr = []*net.TCPAddr{{Port: portDoT}}
 	}
 
+	if portDoQ > 0 {
+		proxyConf.QUICListenAddr = []*net.UDPAddr{{Port: portDoQ}}
+	}
+
 	s = &Server{
 		dnsProxy: &proxy.Proxy{
 			Config: proxyConf,