Implement IETF protocol

doh-client/client.go

@@ -1,68 +1,64 @@
 /*
-    DNS-over-HTTPS
-    Copyright (C) 2017 Star Brilliant <m13253@hotmail.com>
+   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:
+   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 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.
+   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
 
 import (
 	"context"
-	"encoding/json"
-	"fmt"
-	"math/rand"
-	"io/ioutil"
 	"log"
+	"math/rand"
 	"net"
 	"net/http"
 	"net/http/cookiejar"
-	"net/url"
-	"strconv"
-	"strings"
 	"time"
-	"github.com/miekg/dns"
+
 	"../json-dns"
+	"github.com/miekg/dns"
+	"golang.org/x/net/http2"
 )
 
 type Client struct {
-	conf			*config
-	bootstrap		[]string
-	udpServer		*dns.Server
-	tcpServer		*dns.Server
-	httpTransport	*http.Transport
-	httpClient		*http.Client
+	conf          *config
+	bootstrap     []string
+	udpServer     *dns.Server
+	tcpServer     *dns.Server
+	httpTransport *http.Transport
+	httpClient    *http.Client
 }
 
 func NewClient(conf *config) (c *Client, err error) {
-	c = &Client {
+	c = &Client{
 		conf: conf,
 	}
-	c.udpServer = &dns.Server {
-		Addr: conf.Listen,
-		Net: "udp",
+	c.udpServer = &dns.Server{
+		Addr:    conf.Listen,
+		Net:     "udp",
 		Handler: dns.HandlerFunc(c.udpHandlerFunc),
 		UDPSize: 4096,
 	}
-	c.tcpServer = &dns.Server {
-		Addr: conf.Listen,
-		Net: "tcp",
+	c.tcpServer = &dns.Server{
+		Addr:    conf.Listen,
+		Net:     "tcp",
 		Handler: dns.HandlerFunc(c.tcpHandlerFunc),
 	}
 	bootResolver := net.DefaultResolver
@@ -71,37 +67,49 @@ func NewClient(conf *config) (c *Client, err error) {
 		for i, bootstrap := range conf.Bootstrap {
 			bootstrapAddr, err := net.ResolveUDPAddr("udp", bootstrap)
 			if err != nil {
-				bootstrapAddr, err = net.ResolveUDPAddr("udp", "[" + bootstrap + "]:53")
+				bootstrapAddr, err = net.ResolveUDPAddr("udp", "["+bootstrap+"]:53")
+			}
+			if err != nil {
+				return nil, err
 			}
-			if err != nil { return nil, err }
 			c.bootstrap[i] = bootstrapAddr.String()
 		}
-		bootResolver = &net.Resolver {
+		bootResolver = &net.Resolver{
 			PreferGo: true,
 			Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
 				var d net.Dialer
-				num_servers := len(c.bootstrap)
-				bootstrap := c.bootstrap[rand.Intn(num_servers)]
+				numServers := len(c.bootstrap)
+				bootstrap := c.bootstrap[rand.Intn(numServers)]
 				conn, err := d.DialContext(ctx, network, bootstrap)
 				return conn, err
 			},
 		}
 	}
 	c.httpTransport = new(http.Transport)
-	*c.httpTransport = *http.DefaultTransport.(*http.Transport)
-	c.httpTransport.DialContext = (&net.Dialer {
-		Timeout: time.Duration(conf.Timeout) * time.Second,
-		KeepAlive: 30 * time.Second,
-		DualStack: true,
-		Resolver: bootResolver,
-	}).DialContext
-	c.httpTransport.ResponseHeaderTimeout = time.Duration(conf.Timeout) * time.Second
+	c.httpTransport = &http.Transport{
+		DialContext: (&net.Dialer{
+			Timeout:   time.Duration(conf.Timeout) * time.Second,
+			KeepAlive: 30 * time.Second,
+			DualStack: true,
+			Resolver:  bootResolver,
+		}).DialContext,
+		ExpectContinueTimeout: 1 * time.Second,
+		IdleConnTimeout:       90 * time.Second,
+		MaxIdleConns:          100,
+		MaxIdleConnsPerHost:   10,
+		Proxy:                 http.ProxyFromEnvironment,
+		ResponseHeaderTimeout: time.Duration(conf.Timeout) * time.Second,
+		TLSHandshakeTimeout:   time.Duration(conf.Timeout) * time.Second,
+	}
+	http2.ConfigureTransport(c.httpTransport)
 	// Most CDNs require Cookie support to prevent DDoS attack
 	cookieJar, err := cookiejar.New(nil)
-	if err != nil { return nil, err }
-	c.httpClient = &http.Client {
+	if err != nil {
+		return nil, err
+	}
+	c.httpClient = &http.Client{
 		Transport: c.httpTransport,
-		Jar: cookieJar,
+		Jar:       cookieJar,
 	}
 	return c, nil
 }
@@ -114,14 +122,14 @@ func (c *Client) Start() error {
 			log.Println(err)
 		}
 		result <- err
-	} ()
+	}()
 	go func() {
 		err := c.tcpServer.ListenAndServe()
 		if err != nil {
 			log.Println(err)
 		}
 		result <- err
-	} ()
+	}()
 	err := <-result
 	if err != nil {
 		return err
@@ -136,110 +144,7 @@ func (c *Client) handlerFunc(w dns.ResponseWriter, r *dns.Msg, isTCP bool) {
 		return
 	}
 
-	reply := jsonDNS.PrepareReply(r)
-
-	if len(r.Question) != 1 {
-		log.Println("Number of questions is not 1")
-		reply.Rcode = dns.RcodeFormatError
-		w.WriteMsg(reply)
-		return
-	}
-	question := r.Question[0]
-	questionName := strings.ToLower(question.Name)
-	questionType := ""
-	if qtype, ok := dns.TypeToString[question.Qtype]; ok {
-		questionType = qtype
-	} else {
-		questionType = strconv.Itoa(int(question.Qtype))
-	}
-
-	if c.conf.Verbose {
-		fmt.Printf("%s - - [%s] \"%s IN %s\"\n", w.RemoteAddr(), time.Now().Format("02/Jan/2006:15:04:05 -0700"), questionName, questionType)
-	}
-
-	num_servers := len(c.conf.Upstream)
-	upstream := c.conf.Upstream[rand.Intn(num_servers)]
-	requestURL := fmt.Sprintf("%s?name=%s&type=%s", upstream, url.QueryEscape(questionName), url.QueryEscape(questionType))
-
-	if r.CheckingDisabled {
-		requestURL += "&cd=1"
-	}
-
-	udpSize := uint16(512)
-	if opt := r.IsEdns0(); opt != nil {
-		udpSize = opt.UDPSize()
-	}
-
-	ednsClientAddress, ednsClientNetmask := c.findClientIP(w, r)
-	if ednsClientAddress != nil {
-		requestURL += fmt.Sprintf("&edns_client_subnet=%s/%d", ednsClientAddress.String(), ednsClientNetmask)
-	}
-
-	req, err := http.NewRequest("GET", requestURL, nil)
-	if err != nil {
-		log.Println(err)
-		reply.Rcode = dns.RcodeServerFailure
-		w.WriteMsg(reply)
-		return
-	}
-	req.Header.Set("User-Agent", "DNS-over-HTTPS/1.0 (+https://github.com/m13253/dns-over-https)")
-	resp, err := c.httpClient.Do(req)
-	if err != nil {
-		log.Println(err)
-		reply.Rcode = dns.RcodeServerFailure
-		w.WriteMsg(reply)
-		c.httpTransport.CloseIdleConnections()
-		return
-	}
-	if resp.StatusCode != 200 {
-		log.Printf("HTTP error: %s\n", resp.Status)
-		reply.Rcode = dns.RcodeServerFailure
-		w.WriteMsg(reply)
-		contentType := resp.Header.Get("Content-Type")
-		if contentType != "application/json" && !strings.HasPrefix(contentType, "application/json;") {
-			return
-		}
-	}
-
-	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		log.Println(err)
-		reply.Rcode = dns.RcodeServerFailure
-		w.WriteMsg(reply)
-		return
-	}
-
-	var respJson jsonDNS.Response
-	err = json.Unmarshal(body, &respJson)
-	if err != nil {
-		log.Println(err)
-		reply.Rcode = dns.RcodeServerFailure
-		w.WriteMsg(reply)
-		return
-	}
-
-	if respJson.Status != dns.RcodeSuccess && respJson.Comment != "" {
-		log.Printf("DNS error: %s\n", respJson.Comment)
-	}
-
-	fullReply := jsonDNS.Unmarshal(reply, &respJson, udpSize, ednsClientNetmask)
-	buf, err := fullReply.Pack()
-	if err != nil {
-		log.Println(err)
-		reply.Rcode = dns.RcodeServerFailure
-		w.WriteMsg(reply)
-		return
-	}
-	if !isTCP && len(buf) > int(udpSize) {
-		fullReply.Truncated = true
-		buf, err = fullReply.Pack()
-		if err != nil {
-			log.Println(err)
-			return
-		}
-		buf = buf[:udpSize]
-	}
-	w.Write(buf)
+	c.handlerFuncGoogle(w, r, isTCP)
 }
 
 func (c *Client) udpHandlerFunc(w dns.ResponseWriter, r *dns.Msg) {
@@ -251,8 +156,8 @@ func (c *Client) tcpHandlerFunc(w dns.ResponseWriter, r *dns.Msg) {
 }
 
 var (
-	ipv4Mask24	net.IPMask = net.IPMask { 255, 255, 255, 0 }
-	ipv6Mask48	net.IPMask = net.CIDRMask(48, 128)
+	ipv4Mask24 = net.IPMask{255, 255, 255, 0}
+	ipv6Mask48 = net.CIDRMask(48, 128)
 )
 
 func (c *Client) findClientIP(w dns.ResponseWriter, r *dns.Msg) (ednsClientAddress net.IP, ednsClientNetmask uint8) {

doh-client/config.go

@@ -1,57 +1,59 @@
 /*
-    DNS-over-HTTPS
-    Copyright (C) 2017 Star Brilliant <m13253@hotmail.com>
+   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:
+   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 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.
+   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
 
 import (
 	"fmt"
+
 	"github.com/BurntSushi/toml"
 )
 
 type config struct {
-	Listen		string		`toml:"listen"`
-	Upstream	[]string	`toml:"upstream"`
-	Bootstrap	[]string	`toml:"bootstrap"`
-	Timeout		uint		`toml:"timeout"`
-	NoECS		bool		`toml:"no_ecs"`
-	Verbose		bool		`toml:"verbose"`
+	Listen         string   `toml:"listen"`
+	UpstreamGoogle []string `toml:"upstream_google"`
+	UpstreamIETF   []string `toml:"upstream_ietf"`
+	Bootstrap      []string `toml:"bootstrap"`
+	Timeout        uint     `toml:"timeout"`
+	NoECS          bool     `toml:"no_ecs"`
+	Verbose        bool     `toml:"verbose"`
 }
 
 func loadConfig(path string) (*config, error) {
-	conf := &config {}
+	conf := &config{}
 	metaData, err := toml.DecodeFile(path, conf)
 	if err != nil {
 		return nil, err
 	}
 	for _, key := range metaData.Undecoded() {
-		return nil, &configError { fmt.Sprintf("unknown option %q", key.String()) }
+		return nil, &configError{fmt.Sprintf("unknown option %q", key.String())}
 	}
 
 	if conf.Listen == "" {
 		conf.Listen = "127.0.0.1:53"
 	}
-	if len(conf.Upstream) == 0 {
-		conf.Upstream = []string { "https://dns.google.com/resolve" }
+	if len(conf.UpstreamGoogle) == 0 && len(conf.UpstreamIETF) == 0 {
+		conf.UpstreamGoogle = []string{"https://dns.google.com/resolve"}
 	}
 	if conf.Timeout == 0 {
 		conf.Timeout = 10
@@ -61,7 +63,7 @@ func loadConfig(path string) (*config, error) {
 }
 
 type configError struct {
-	err		string
+	err string
 }
 
 func (e *configError) Error() string {

doh-client/doh-client.conf

@@ -3,9 +3,12 @@ listen = "127.0.0.1:53"
 
 # HTTP path for upstream resolver
 # If multiple servers are specified, a random one will be chosen each time.
-upstream = [
+upstream_google = [
     "https://dns.google.com/resolve",
 ]
+upstream_ietf = [
+    "https://dns.google.com/experimental",
+]
 
 # Bootstrap DNS server to resolve the address of the upstream resolver
 # If multiple servers are specified, a random one will be chosen each time.

doh-client/google.go

@@ -0,0 +1,147 @@
+/*
+   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
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"math/rand"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+	"time"
+
+	"../json-dns"
+	"github.com/miekg/dns"
+)
+
+func (c *Client) handlerFuncGoogle(w dns.ResponseWriter, r *dns.Msg, isTCP bool) {
+	reply := jsonDNS.PrepareReply(r)
+
+	if len(r.Question) != 1 {
+		log.Println("Number of questions is not 1")
+		reply.Rcode = dns.RcodeFormatError
+		w.WriteMsg(reply)
+		return
+	}
+	question := r.Question[0]
+	questionName := strings.ToLower(question.Name)
+	questionType := ""
+	if qtype, ok := dns.TypeToString[question.Qtype]; ok {
+		questionType = qtype
+	} else {
+		questionType = strconv.Itoa(int(question.Qtype))
+	}
+
+	if c.conf.Verbose {
+		fmt.Printf("%s - - [%s] \"%s IN %s\"\n", w.RemoteAddr(), time.Now().Format("02/Jan/2006:15:04:05 -0700"), questionName, questionType)
+	}
+
+	numServers := len(c.conf.UpstreamGoogle)
+	upstream := c.conf.UpstreamGoogle[rand.Intn(numServers)]
+	requestURL := fmt.Sprintf("%s?name=%s&type=%s", upstream, url.QueryEscape(questionName), url.QueryEscape(questionType))
+
+	if r.CheckingDisabled {
+		requestURL += "&cd=1"
+	}
+
+	udpSize := uint16(512)
+	if opt := r.IsEdns0(); opt != nil {
+		udpSize = opt.UDPSize()
+	}
+
+	ednsClientAddress, ednsClientNetmask := c.findClientIP(w, r)
+	if ednsClientAddress != nil {
+		requestURL += fmt.Sprintf("&edns_client_subnet=%s/%d", ednsClientAddress.String(), ednsClientNetmask)
+	}
+
+	req, err := http.NewRequest("GET", requestURL, nil)
+	if err != nil {
+		log.Println(err)
+		reply.Rcode = dns.RcodeServerFailure
+		w.WriteMsg(reply)
+		return
+	}
+	req.Header.Set("User-Agent", "DNS-over-HTTPS/1.0 (+https://github.com/m13253/dns-over-https)")
+	resp, err := c.httpClient.Do(req)
+	if err != nil {
+		log.Println(err)
+		reply.Rcode = dns.RcodeServerFailure
+		w.WriteMsg(reply)
+		c.httpTransport.CloseIdleConnections()
+		return
+	}
+	if resp.StatusCode != 200 {
+		log.Printf("HTTP error: %s\n", resp.Status)
+		reply.Rcode = dns.RcodeServerFailure
+		w.WriteMsg(reply)
+		contentType := resp.Header.Get("Content-Type")
+		if contentType != "application/json" && !strings.HasPrefix(contentType, "application/json;") {
+			return
+		}
+	}
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		log.Println(err)
+		reply.Rcode = dns.RcodeServerFailure
+		w.WriteMsg(reply)
+		return
+	}
+
+	var respJSON jsonDNS.Response
+	err = json.Unmarshal(body, &respJSON)
+	if err != nil {
+		log.Println(err)
+		reply.Rcode = dns.RcodeServerFailure
+		w.WriteMsg(reply)
+		return
+	}
+
+	if respJSON.Status != dns.RcodeSuccess && respJSON.Comment != "" {
+		log.Printf("DNS error: %s\n", respJSON.Comment)
+	}
+
+	fullReply := jsonDNS.Unmarshal(reply, &respJSON, udpSize, ednsClientNetmask)
+	buf, err := fullReply.Pack()
+	if err != nil {
+		log.Println(err)
+		reply.Rcode = dns.RcodeServerFailure
+		w.WriteMsg(reply)
+		return
+	}
+	if !isTCP && len(buf) > int(udpSize) {
+		fullReply.Truncated = true
+		buf, err = fullReply.Pack()
+		if err != nil {
+			log.Println(err)
+			return
+		}
+		buf = buf[:udpSize]
+	}
+	w.Write(buf)
+}

doh-client/main.go

@@ -1,24 +1,24 @@
 /*
-    DNS-over-HTTPS
-    Copyright (C) 2017 Star Brilliant <m13253@hotmail.com>
+   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:
+   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 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.
+   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