Pull request: upstream: change doq port to 853

Merge in DNS/dnsproxy from 4276-doq-port to master

Updates AdguardTeam/AdGuardHome#4276.

Squashed commit of the following:

commit 3c889cd
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Mon Mar 21 20:10:40 2022 +0300

    upstream: rm deprecated stuff

commit 94f86fb
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Mon Mar 21 20:04:08 2022 +0300

    upstream: change doq port to 853

README.md

@@ -171,9 +171,9 @@ Runs a DNS-over-HTTPS proxy on `127.0.0.1:443`.
 ./dnsproxy -l 127.0.0.1 --https-port=443 --tls-crt=example.crt --tls-key=example.key -u 8.8.8.8:53 -p 0
 ```
 
-Runs a DNS-over-QUIC proxy on `127.0.0.1:8853`.
+Runs a DNS-over-QUIC proxy on `127.0.0.1:853`.
 ```shell
-./dnsproxy -l 127.0.0.1 --quic-port=8853 --tls-crt=example.crt --tls-key=example.key -u 8.8.8.8:53 -p 0
+./dnsproxy -l 127.0.0.1 --quic-port=853 --tls-crt=example.crt --tls-key=example.key -u 8.8.8.8:53 -p 0
 ```
 
 Runs a DNSCrypt proxy on `127.0.0.1:443`.

upstream/upstream.go

@@ -63,14 +63,11 @@ const (
 	// defaultPortDoT is the default port for DNS-over-TLS.
 	defaultPortDoT = 853
 
-	// defaultPortDoQ is the default port for DNS-over-QUIC.
+	// defaultPortDoQ is the default port for DNS-over-QUIC.  Prior to version
+	// -10 of the draft experiments were directed to use ports 8853, 784.
 	//
-	// Early experiments MAY use port 8853. This port is marked in the IANA
-	// registry as unassigned.  Note that prior to version -02 of this draft,
-	// experiments were directed to use port 784.
-	//
-	// See https://datatracker.ietf.org/doc/html/draft-ietf-dprive-dnsoquic-02#section-10.2.1.
-	defaultPortDoQ = 8853
+	// See https://datatracker.ietf.org/doc/html/draft-ietf-dprive-dnsoquic-10#section-10.2.
+	defaultPortDoQ = 853
 )
 
 // AddressToUpstream converts addr to an Upstream instance:
@@ -126,15 +123,6 @@ func urlToUpstream(uu *url.URL, opts *Options) (u Upstream, err error) {
 	switch sch := uu.Scheme; sch {
 	case "sdns":
 		return stampToUpstream(uu, opts)
-	// TODO(e.burkov): Remove in the next major-minor release.
-	case "dns":
-		log.Info(
-			"warning: using %q scheme is deprecated and will be removed in future versions; "+
-				"use \"udp\" instead",
-			sch,
-		)
-
-		return newPlain(uu, opts.Timeout, false), nil
 	case "udp", "tcp":
 		return newPlain(uu, opts.Timeout, sch == "tcp"), nil
 	case "quic":

upstream/upstream_test.go

@@ -221,6 +221,10 @@ func TestAddressToUpstream(t *testing.T) {
 		addr: "one.one.one.one",
 		opt:  nil,
 		want: "one.one.one.one:53",
+	}, {
+		addr: "udp://one.one.one.one",
+		opt:  nil,
+		want: "one.one.one.one:53",
 	}, {
 		addr: "tcp://one.one.one.one",
 		opt:  opt,