Release 1.3.5

Hopefully we can improve the availability of DoH under unstable network environments.

Changelog.md

@@ -0,0 +1,85 @@
+# Changelog
+
+This Changelog records major changes between versions.
+
+Not all changes are recorded. Please check git log for details.
+
+## Version 1.3.5
+
+- Limit the frequency of creating HTTP client on bad network condition
+
+## Version 1.3.4
+
+- doh-client now silently fails in case of network error to prevent caching of SERVFAIL
+- EDNS0 is now inserted to the beginning of OPT section, to ensure DNSSEC signatures are at the end
+- Improve building system
+- Update documents
+
+## Version 1.3.3
+
+- Take User-Agent out of common library, that would be better for packaging
+
+## Version 1.3.2
+
+- Fix version string in HTTP User-Agent
+
+## Version 1.3.1
+
+- Fix the "address already in use" issue
+
+## Version 1.3.0
+
+- Breaking change: Add client / server support for multiple listen address
+  The `listen` option in the configuration file is a list now
+
+## Version 1.2.1
+
+- Update protocol to IETF draft-07
+- Update installation documentations for Ubuntu / Debian
+
+## Version 1.2.0
+
+- Add installation documentations for Ubuntu / Debian
+- Include CloudFlare DOH server (1.1.1.1, 1.0.0.1) in default configuration
+- Fix a problem causing `go get` to fail due to relative paths
+- Add documentation about `/etc/hosts` preloading
+
+## Version 1.1.4
+
+- Add `no_cookies` option
+- Add documentation on privacy issues
+- Adapt for CloudFlare DNS service
+- Fix a problem causing a single network failure blocking future requests
+- Add experimental macOS support
+
+## Version 1.1.3
+
+- Unsupported Content-Type now generates HTTP error code 415
+
+## Version 1.1.2
+
+- Adapt to IETF protocol
+- Optimize for HTTP caches
+
+## Version 1.1.1
+
+- Adapt to IETF protocol
+- Optimize for HTTP caches
+- Add documentation for uninstallation instructions
+- Fix build issues
+
+## Version 1.1.0
+
+- Adpat to IETF protocol
+- Fix issues regarding to HTTP caching
+- Require Go 1.9 to build now
+- Fix systemd issue
+
+## Version 1.0.1
+
+- Fix build issues
+
+## Version 1.0.0
+
+- First release
+- Relicense as MIT license

Makefile

@@ -2,6 +2,7 @@
 
 GOBUILD=go build
 GOGET=go get -d -v
+GOGET_UPDATE=go get -d -u -v
 PREFIX=/usr/local
 ifeq ($(shell uname),Darwin)
 	CONFDIR=/usr/local/etc/dns-over-https
@@ -40,10 +41,12 @@ uninstall:
 	fi
 
 deps:
+	@# I am not sure if it is the correct way to keep the common library updated
+	$(GOGET_UPDATE) github.com/m13253/dns-over-https/json-dns
 	$(GOGET) ./doh-client ./doh-server
 
-doh-client/doh-client: deps doh-client/client.go doh-client/config.go doh-client/google.go doh-client/ietf.go doh-client/main.go json-dns/error.go json-dns/globalip.go json-dns/marshal.go json-dns/response.go json-dns/unmarshal.go
+doh-client/doh-client: deps doh-client/client.go doh-client/config.go doh-client/google.go doh-client/ietf.go doh-client/main.go doh-client/version.go json-dns/error.go json-dns/globalip.go json-dns/marshal.go json-dns/response.go json-dns/unmarshal.go
 	cd doh-client && $(GOBUILD)
 
-doh-server/doh-server: deps doh-server/config.go doh-server/google.go doh-server/ietf.go doh-server/main.go doh-server/server.go json-dns/error.go json-dns/globalip.go json-dns/marshal.go json-dns/response.go json-dns/unmarshal.go
+doh-server/doh-server: deps doh-server/config.go doh-server/google.go doh-server/ietf.go doh-server/main.go doh-server/server.go doh-server/version.go json-dns/error.go json-dns/globalip.go json-dns/marshal.go json-dns/response.go json-dns/unmarshal.go
 	cd doh-server && $(GOBUILD)

Readme.md

@@ -70,6 +70,9 @@ The following is a typical DNS-over-HTTPS architecture:
 Although DNS-over-HTTPS can work alone, a HTTP service muxer would be useful as
 you can host DNS-over-HTTPS along with other HTTPS services.
 
+HTTP/2 with at least TLS v1.3 is recommended. OCSP stapling must be enabled,
+otherwise DNS recursion may happen.
+
 ## DNSSEC
 
 DNS-over-HTTPS is compatible with DNSSEC, and requests DNSSEC signatures by
@@ -90,8 +93,10 @@ EDNS0-Client-Subnet is affecting your privacy, you can set `no_ecs = true` in
 `/etc/dns-over-https/doh-client.conf`, with the cost of slower video streaming
 or software downloading speed.
 
-If your server is backed by `unbound` or `bind`, you probably want to enable
+To ultilize ECS, `X-Forwarded-For` or `X-Real-IP` should be enabled on your
-the EDNS0-Client-Subnet feature in their configuration files as well.
+HTTP service muxer. If your server is backed by `unbound` or `bind`, you
+probably want to configure it to enable the EDNS0-Client-Subnet feature as
+well.
 
 ## Protocol compatibility
 

doh-client/client.go

@@ -40,15 +40,16 @@ import (
 )
 
 type Client struct {
-	conf              *config
+	conf                 *config
-	bootstrap         []string
+	bootstrap            []string
-	udpServer         *dns.Server
+	udpServers           []*dns.Server
-	tcpServer         *dns.Server
+	tcpServers           []*dns.Server
-	bootstrapResolver *net.Resolver
+	bootstrapResolver    *net.Resolver
-	cookieJar         *cookiejar.Jar
+	cookieJar            *cookiejar.Jar
-	httpClientMux     *sync.RWMutex
+	httpClientMux        *sync.RWMutex
-	httpTransport     *http.Transport
+	httpTransport        *http.Transport
-	httpClient        *http.Client
+	httpClient           *http.Client
+	httpClientLastCreate time.Time
 }
 
 type DNSRequest struct {
@@ -64,16 +65,21 @@ func NewClient(conf *config) (c *Client, err error) {
 	c = &Client{
 		conf: conf,
 	}
-	c.udpServer = &dns.Server{
+
-		Addr:    conf.Listen,
+	udpHandler := dns.HandlerFunc(c.udpHandlerFunc)
-		Net:     "udp",
+	tcpHandler := dns.HandlerFunc(c.tcpHandlerFunc)
-		Handler: dns.HandlerFunc(c.udpHandlerFunc),
+	for _, addr := range conf.Listen {
-		UDPSize: 4096,
+		c.udpServers = append(c.udpServers, &dns.Server{
-	}
+			Addr:    addr,
-	c.tcpServer = &dns.Server{
+			Net:     "udp",
-		Addr:    conf.Listen,
+			Handler: udpHandler,
-		Net:     "tcp",
+			UDPSize: dns.DefaultMsgSize,
-		Handler: dns.HandlerFunc(c.tcpHandlerFunc),
+		})
+		c.tcpServers = append(c.tcpServers, &dns.Server{
+			Addr:    addr,
+			Net:     "tcp",
+			Handler: tcpHandler,
+		})
 	}
 	c.bootstrapResolver = net.DefaultResolver
 	if len(conf.Bootstrap) != 0 {
@@ -119,6 +125,9 @@ func NewClient(conf *config) (c *Client, err error) {
 func (c *Client) newHTTPClient() error {
 	c.httpClientMux.Lock()
 	defer c.httpClientMux.Unlock()
+	if !c.httpClientLastCreate.IsZero() && time.Now().Sub(c.httpClientLastCreate) < time.Duration(c.conf.Timeout)*time.Second {
+		return nil
+	}
 	if c.httpTransport != nil {
 		c.httpTransport.CloseIdleConnections()
 	}
@@ -145,31 +154,30 @@ func (c *Client) newHTTPClient() error {
 		Transport: c.httpTransport,
 		Jar:       c.cookieJar,
 	}
+	c.httpClientLastCreate = time.Now()
 	return nil
 }
 
 func (c *Client) Start() error {
-	result := make(chan error)
+	results := make(chan error, len(c.udpServers)+len(c.tcpServers))
-	go func() {
+	for _, srv := range append(c.udpServers, c.tcpServers...) {
-		err := c.udpServer.ListenAndServe()
+		go func(srv *dns.Server) {
-		if err != nil {
+			err := srv.ListenAndServe()
-			log.Println(err)
+			if err != nil {
-		}
+				log.Println(err)
-		result <- err
+			}
-	}()
+			results <- err
-	go func() {
+		}(srv)
-		err := c.tcpServer.ListenAndServe()
-		if err != nil {
-			log.Println(err)
-		}
-		result <- err
-	}()
-	err := <-result
-	if err != nil {
-		return err
 	}
-	err = <-result
+
-	return err
+	for i := 0; i < cap(results); i++ {
+		err := <-results
+		if err != nil {
+			return err
+		}
+	}
+	close(results)
+	return nil
 }
 
 func (c *Client) handlerFunc(w dns.ResponseWriter, r *dns.Msg, isTCP bool) {

doh-client/config.go

@@ -30,7 +30,7 @@ import (
 )
 
 type config struct {
-	Listen         string   `toml:"listen"`
+	Listen         []string `toml:"listen"`
 	UpstreamGoogle []string `toml:"upstream_google"`
 	UpstreamIETF   []string `toml:"upstream_ietf"`
 	Bootstrap      []string `toml:"bootstrap"`
@@ -50,8 +50,8 @@ func loadConfig(path string) (*config, error) {
 		return nil, &configError{fmt.Sprintf("unknown option %q", key.String())}
 	}
 
-	if conf.Listen == "" {
+	if len(conf.Listen) == 0 {
-		conf.Listen = "127.0.0.1:53"
+		conf.Listen = []string{"127.0.0.1:53", "[::1]:53"}
 	}
 	if len(conf.UpstreamGoogle) == 0 && len(conf.UpstreamIETF) == 0 {
 		conf.UpstreamGoogle = []string{"https://dns.google.com/resolve"}

doh-client/doh-client.conf

@@ -1,5 +1,8 @@
 # DNS listen port
-listen = "127.0.0.1:53"
+listen = [
+    "127.0.0.1:53",
+    "[::1]:53",
+]
 
 # HTTP path for upstream resolver
 # If multiple servers are specified, a random one will be chosen each time.
@@ -44,7 +47,7 @@ bootstrap = [
 ]
 
 # Timeout for upstream request
-timeout = 10
+timeout = 30
 
 # Disable HTTP Cookies
 #

doh-client/google.go

@@ -92,7 +92,7 @@ func (c *Client) generateRequestGoogle(w dns.ResponseWriter, r *dns.Msg, isTCP b
 		}
 	}
 	req.Header.Set("Accept", "application/json, application/dns-message, application/dns-udpwireformat")
-	req.Header.Set("User-Agent", "DNS-over-HTTPS/1.1 (+https://github.com/m13253/dns-over-https)")
+	req.Header.Set("User-Agent", USER_AGENT)
 	c.httpClientMux.RLock()
 	resp, err := c.httpClient.Do(req)
 	c.httpClientMux.RUnlock()

doh-client/ietf.go

@@ -73,9 +73,9 @@ func (c *Client) generateRequestIETF(w dns.ResponseWriter, r *dns.Msg, isTCP boo
 		opt = new(dns.OPT)
 		opt.Hdr.Name = "."
 		opt.Hdr.Rrtype = dns.TypeOPT
-		opt.SetUDPSize(4096)
+		opt.SetUDPSize(dns.DefaultMsgSize)
 		opt.SetDo(false)
-		r.Extra = append(r.Extra, opt)
+		r.Extra = append([]dns.RR{opt}, r.Extra...)
 	} else {
 		udpSize = opt.UDPSize()
 	}
@@ -134,9 +134,8 @@ func (c *Client) generateRequestIETF(w dns.ResponseWriter, r *dns.Msg, isTCP boo
 	if len(requestURL) < 2048 {
 		req, err = http.NewRequest("GET", requestURL, nil)
 		if err != nil {
+			// Do not respond, silently fail to prevent caching of SERVFAIL
 			log.Println(err)
-			reply.Rcode = dns.RcodeServerFailure
-			w.WriteMsg(reply)
 			return &DNSRequest{
 				err: err,
 			}
@@ -144,9 +143,8 @@ func (c *Client) generateRequestIETF(w dns.ResponseWriter, r *dns.Msg, isTCP boo
 	} else {
 		req, err = http.NewRequest("POST", upstream, bytes.NewReader(requestBinary))
 		if err != nil {
+			// Do not respond, silently fail to prevent caching of SERVFAIL
 			log.Println(err)
-			reply.Rcode = dns.RcodeServerFailure
-			w.WriteMsg(reply)
 			return &DNSRequest{
 				err: err,
 			}
@@ -154,7 +152,7 @@ func (c *Client) generateRequestIETF(w dns.ResponseWriter, r *dns.Msg, isTCP boo
 		req.Header.Set("Content-Type", "application/dns-message")
 	}
 	req.Header.Set("Accept", "application/dns-message, application/dns-udpwireformat, application/json")
-	req.Header.Set("User-Agent", "DNS-over-HTTPS/1.1 (+https://github.com/m13253/dns-over-https)")
+	req.Header.Set("User-Agent", USER_AGENT)
 	c.httpClientMux.RLock()
 	resp, err := c.httpClient.Do(req)
 	c.httpClientMux.RUnlock()

doh-client/version.go

@@ -0,0 +1,29 @@
+/*
+   DNS-over-HTTPS
+   Copyright (C) 2017-2018 Star Brilliant <m13253@hotmail.com>
+
+   Permission is hereby granted, free of charge, to any person obtaining a
+   copy of this software and associated documentation files (the "Software"),
+   to deal in the Software without restriction, including without limitation
+   the rights to use, copy, modify, merge, publish, distribute, sublicense,
+   and/or sell copies of the Software, and to permit persons to whom the
+   Software is furnished to do so, subject to the following conditions:
+
+   The above copyright notice and this permission notice shall be included in
+   all copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+   DEALINGS IN THE SOFTWARE.
+*/
+
+package main
+
+const (
+	VERSION    = "1.3.5"
+	USER_AGENT = "DNS-over-HTTPS/" + VERSION + " (+https://github.com/m13253/dns-over-https)"
+)

doh-server/config.go

@@ -30,7 +30,7 @@ import (
 )
 
 type config struct {
-	Listen   string   `toml:"listen"`
+	Listen   []string `toml:"listen"`
 	Cert     string   `toml:"cert"`
 	Key      string   `toml:"key"`
 	Path     string   `toml:"path"`
@@ -51,9 +51,10 @@ func loadConfig(path string) (*config, error) {
 		return nil, &configError{fmt.Sprintf("unknown option %q", key.String())}
 	}
 
-	if conf.Listen == "" {
+	if len(conf.Listen) == 0 {
-		conf.Listen = "127.0.0.1:8053"
+		conf.Listen = []string{"127.0.0.1:8053", "[::1]:8053"}
 	}
+
 	if conf.Path == "" {
 		conf.Path = "/dns-query"
 	}

doh-server/doh-server.conf

@@ -1,5 +1,8 @@
 # HTTP listen port
-listen = "127.0.0.1:8053"
+listen = [
+    "127.0.0.1:8053",
+    "[::1]:8053",
+]
 
 # TLS certification file
 cert = ""

doh-server/google.go

@@ -150,7 +150,7 @@ func (s *Server) parseRequestGoogle(w http.ResponseWriter, r *http.Request) *DNS
 	opt := new(dns.OPT)
 	opt.Hdr.Name = "."
 	opt.Hdr.Rrtype = dns.TypeOPT
-	opt.SetUDPSize(4096)
+	opt.SetUDPSize(dns.DefaultMsgSize)
 	opt.SetDo(true)
 	if ednsClientAddress != nil {
 		edns0Subnet := new(dns.EDNS0_SUBNET)

doh-server/ietf.go

@@ -93,9 +93,9 @@ func (s *Server) parseRequestIETF(w http.ResponseWriter, r *http.Request) *DNSRe
 		opt = new(dns.OPT)
 		opt.Hdr.Name = "."
 		opt.Hdr.Rrtype = dns.TypeOPT
-		opt.SetUDPSize(4096)
+		opt.SetUDPSize(dns.DefaultMsgSize)
 		opt.SetDo(false)
-		msg.Extra = append(msg.Extra, opt)
+		msg.Extra = append([]dns.RR{opt}, msg.Extra...)
 	}
 	var edns0Subnet *dns.EDNS0_SUBNET
 	for _, option := range opt.Option {

doh-server/main.go

@@ -43,8 +43,5 @@ func main() {
 	}
 
 	server := NewServer(conf)
-	err = server.Start()
+	_ = server.Start()
-	if err != nil {
-		log.Fatalln(err)
-	}
 }

doh-server/server.go

@@ -58,6 +58,7 @@ func NewServer(conf *config) (s *Server) {
 		conf: conf,
 		udpClient: &dns.Client{
 			Net:     "udp",
+			UDPSize: dns.DefaultMsgSize,
 			Timeout: time.Duration(conf.Timeout) * time.Second,
 		},
 		tcpClient: &dns.Client{
@@ -75,15 +76,35 @@ func (s *Server) Start() error {
 	if s.conf.Verbose {
 		servemux = handlers.CombinedLoggingHandler(os.Stdout, servemux)
 	}
-	if s.conf.Cert != "" || s.conf.Key != "" {
+	results := make(chan error, len(s.conf.Listen))
-		return http.ListenAndServeTLS(s.conf.Listen, s.conf.Cert, s.conf.Key, servemux)
+	for _, addr := range s.conf.Listen {
+		go func(addr string) {
+			var err error
+			if s.conf.Cert != "" || s.conf.Key != "" {
+				err = http.ListenAndServeTLS(addr, s.conf.Cert, s.conf.Key, servemux)
+			} else {
+				err = http.ListenAndServe(addr, servemux)
+			}
+			if err != nil {
+				log.Println(err)
+			}
+			results <- err
+		}(addr)
 	}
-	return http.ListenAndServe(s.conf.Listen, servemux)
+	// wait for all handlers
+	for i := 0; i < cap(results); i++ {
+		err := <-results
+		if err != nil {
+			return err
+		}
+	}
+	close(results)
+	return nil
 }
 
 func (s *Server) handlerFunc(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("Server", "DNS-over-HTTPS/1.1 (+https://github.com/m13253/dns-over-https)")
+	w.Header().Set("Server", USER_AGENT)
-	w.Header().Set("X-Powered-By", "DNS-over-HTTPS/1.1 (+https://github.com/m13253/dns-over-https)")
+	w.Header().Set("X-Powered-By", USER_AGENT)
 
 	if r.Form == nil {
 		const maxMemory = 32 << 20 // 32 MB

doh-server/version.go

@@ -0,0 +1,29 @@
+/*
+   DNS-over-HTTPS
+   Copyright (C) 2017-2018 Star Brilliant <m13253@hotmail.com>
+
+   Permission is hereby granted, free of charge, to any person obtaining a
+   copy of this software and associated documentation files (the "Software"),
+   to deal in the Software without restriction, including without limitation
+   the rights to use, copy, modify, merge, publish, distribute, sublicense,
+   and/or sell copies of the Software, and to permit persons to whom the
+   Software is furnished to do so, subject to the following conditions:
+
+   The above copyright notice and this permission notice shall be included in
+   all copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+   DEALINGS IN THE SOFTWARE.
+*/
+
+package main
+
+const (
+	VERSION    = "1.3.5"
+	USER_AGENT = "DNS-over-HTTPS/" + VERSION + " (+https://github.com/m13253/dns-over-https)"
+)