docs: explain how to use DNS-over-TLS with nginx/STunnel

chore: upgrade deps

.github/workflows/go.yml

@@ -0,0 +1,37 @@
+name: Go build for Linux
+on: [push, pull_request]
+jobs:
+
+  build:
+    name: Build
+    runs-on: ubuntu-18.04
+    steps:
+
+    - name: Set up Go
+      uses: actions/setup-go@v2
+      with:
+        go-version: 1.18
+      id: go
+
+    - name: Check out repository
+      uses: actions/checkout@v2
+
+    - name: Linux build
+      run: |
+        make
+
+    - name: Upload Linux build
+      uses: actions/upload-artifact@v2
+      with:
+        name: linux-amd64
+        path: |
+          doh-client/doh-client
+          doh-server/doh-server
+
+    - name: Cache
+      uses: actions/cache@v2
+      with:
+        # A directory to store and save the cache
+        path: ~/go/pkg/mod
+        # An explicit key for restoring and saving the cache
+        key: ${{ runner.os }}-${{ hashFiles('**/go.sum') }}

.gitignore

@@ -3,6 +3,9 @@
 *.dll
 *.so
 *.dylib
+darwin-wrapper/doh-logger
+doh-client/doh-client
+doh-server/doh-server
 
 # Test binary, build with `go test -c`
 *.test
@@ -14,3 +17,4 @@
 .glide/
 
 .idea/
+vendor/

Changelog.md

@@ -4,6 +4,38 @@ This Changelog records major changes between versions.
 
 Not all changes are recorded. Please check git log for details.
 
+## Version 2.3.1
+
+- No new features in this release
+- Bumped versions of Go toolchain and third-party dependencies, requested by #128
+
+## Version 2.3.0
+
+- The repository now conforms to the Go semvar standard (Fixed #115, thanks to @leiless)
+
+## Version 2.2.5
+
+- Add client certificate authentication
+- Fixing documentation related to Docker
+
+## Version 2.2.4
+
+- Add options to configure ECS netmask length
+- Add an option to disable TLS verification (Note: dangerous)
+
+## Version 2.2.3
+
+- Use the library ipTree to determine whether an IP is global routable, improving the performance
+- Google's 8.8.8.8 resolver is now marked as "Good ECS" in the example configuration file
+
+## Version 2.2.2
+
+- Allow client to opt-out EDNS0 Client Support
+- [JSON-DoH] Honor DNSSEC OK flag for incoming DNS requests
+- [JSON-DoH] Add support for non-standard response formats
+- `X-Real-IP` is now used in logging if set by frontend load balancer
+- Fix documentation
+
 ## Version 2.2.1
 
 - Fix messy log

Dockerfile.client

@@ -15,7 +15,8 @@ ADD doh-client/doh-client.conf /doh-client.conf
 RUN sed -i '$!N;s/"127.0.0.1:53",.*"127.0.0.1:5380",/":53",/;P;D' /doh-client.conf
 RUN sed -i '$!N;s/"\[::1\]:53",.*"\[::1\]:5380",/":5380",/;P;D' /doh-client.conf
 
-EXPOSE 53
+EXPOSE 53/udp
+EXPOSE 53/tcp
 EXPOSE 5380
 
 ENTRYPOINT ["/doh-client"]

Makefile

@@ -1,15 +1,11 @@
-.PHONY: all clean install uninstall deps
+.PHONY: all clean install uninstall
 
 PREFIX = /usr/local
 
 ifeq ($(GOROOT),)
 GOBUILD = go build
-GOGET = go get -d -v
-GOGET_UPDATE = go get -d -u -v
 else
 GOBUILD = $(GOROOT)/bin/go build
-GOGET = $(GOROOT)/bin/go get -d -v
-GOGET_UPDATE = $(GOROOT)/bin/go get -d -u -v
 endif
 
 ifeq ($(shell uname),Darwin)
@@ -57,14 +53,8 @@ uninstall:
 		$(MAKE) -C launchd uninstall "DESTDIR=$(DESTDIR)"; \
 	fi
 
-deps:
+doh-client/doh-client: doh-client/client.go doh-client/config/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
-	@# I am not sure if it is the correct way to keep the common library updated
-	$(GOGET_UPDATE) github.com/m13253/dns-over-https/doh-client/config
-	$(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/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 doh-server/version.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: 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

@@ -4,57 +4,68 @@ DNS-over-HTTPS
 Client and server software to query DNS over HTTPS, using [Google DNS-over-HTTPS protocol](https://developers.google.com/speed/public-dns/docs/dns-over-https)
 and [IETF DNS-over-HTTPS (RFC 8484)](https://www.rfc-editor.org/rfc/rfc8484.txt).
 
-## Guide
+## Guides
 
-[Tutorial to setup your own DNS-over-HTTPS (DoH) server](https://www.aaflalo.me/2018/10/tutorial-setup-dns-over-https-server/). (Thanks to Antoine Aflalo)
+- [Tutorial: Setup your own DNS-over-HTTPS (DoH) server](https://www.aaflalo.me/2018/10/tutorial-setup-dns-over-https-server/). (Thanks to Antoine Aflalo)
+- [Tutorial: Setup your own Docker based DNS-over-HTTPS (DoH) server](https://github.com/satishweb/docker-doh/blob/master/README.md). (Thanks to Satish Gaikwad)
 
 ## Installing
+### From Source
+- Install [Go](https://golang.org), at least version 1.13. The newer the better.
+> Note for Debian/Ubuntu users: You need to set `$GOROOT` if you could not get your new version of Go selected by the Makefile.)
 
-Install [Go](https://golang.org), at least version 1.10.
+- First create an empty directory, used for `$GOPATH`:
-
+```bash
-(Note for Debian/Ubuntu users: You need to set `$GOROOT` if you could not get your new version of Go selected by the Makefile.)
-
-First create an empty directory, used for `$GOPATH`:
-
 mkdir ~/gopath
 export GOPATH=~/gopath
-
+```
-To build the program, type:
+- To build the program, type:
-
+```bash
 make
-
+```
-To install DNS-over-HTTPS as Systemd services, type:
+- To install DNS-over-HTTPS as Systemd services, type:
-
+```bash
 sudo make install
-
+```
-By default, [Google DNS over HTTPS](https://dns.google.com) is used. It should
+- By default, [Google DNS over HTTPS](https://dns.google.com) is used. It should
 work for most users (except for People's Republic of China). If you need to
 modify the default settings, type:
-
+```bash
 sudoedit /etc/dns-over-https/doh-client.conf
-
+```
-To automatically start DNS-over-HTTPS client as a system service, type:
+- To automatically start DNS-over-HTTPS client as a system service, type:
-
+```bash
 sudo systemctl start doh-client.service
 sudo systemctl enable doh-client.service
+```
+- Then, modify your DNS settings (usually with NetworkManager) to 127.0.0.1.
 
-Then, modify your DNS settings (usually with NetworkManager) to 127.0.0.1.
+- To test your configuration, type:
-
+```bash
-To test your configuration, type:
-
 dig www.google.com
-
+Output:
-If it is OK, you will see:
-
 ;; SERVER: 127.0.0.1#53(127.0.0.1)
+```
+#### Uninstall
 
-### Uninstalling
+- To uninstall, type:
-
+```bash
-To uninstall, type:
-
 sudo make uninstall
+```
+> Note: The configuration files are kept at `/etc/dns-over-https`. Remove them manually if you want.
 
-The configuration files are kept at `/etc/dns-over-https`. Remove them manually if you want.
+### Using docker image
+```bash
+docker run -d --name doh-server \
+  -p 8053:8053 \
+  -e UPSTREAM_DNS_SERVER="udp:8.8.8.8:53" \
+  -e DOH_HTTP_PREFIX="/dns-query" \
+  -e DOH_SERVER_LISTEN=":8053" \
+  -e DOH_SERVER_TIMEOUT="10" \
+  -e DOH_SERVER_TRIES="3" \
+  -e DOH_SERVER_VERBOSE="false" \
+  satishweb/doh-server
+```
 
 ## Server Configuration
 
@@ -79,8 +90,19 @@ 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.
 
-### Example configuration: Apache
+### Configuration file
 
+The main configuration file is `doh-client.conf`.
+
+**Server selectors.** If several upstream servers are set, one is selected according to `upstream_selector` for each request. With `upstream_selector = "random"`, a random upstream server will be chosen for each request.
+
+```toml
+# available selector: random (default) or weighted_round_robin or lvs_weighted_round_robin
+upstream_selector = "random"
+```
+
+### Example configuration: Apache
+```bash
 SSLProtocol TLSv1.2
 SSLHonorCipherOrder On
 SSLCipherSuite ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+3DES:!aNULL:!MD5:!DSS:!eNULL:!EXP:!LOW:!MD5
@@ -93,11 +115,11 @@ otherwise DNS recursion may happen.
     ProxyPass /dns-query http://[::1]:8053/dns-query
     ProxyPassReverse /dns-query http://[::1]:8053/dns-query
 </VirtualHost>
-
+```
 (Credit: [Joan Moreau](https://github.com/m13253/dns-over-https/issues/51#issuecomment-526820884))
 
 ### Example configuration: Nginx
-
+```bash
 server {
   listen       443 ssl http2 default_server;
   listen       [::]:443 ssl http2 default_server;
@@ -131,35 +153,146 @@ otherwise DNS recursion may happen.
     proxy_set_header X-Real-IP $remote_addr;
   }
 }
-
+```
 (Credit: [Cipherli.st](https://cipherli.st/))
 
-### Example configuration: Caddy
+### Example configuration: Caddy (v2)
+```bash
+my.server.name {
+        reverse_proxy * localhost:8053
+        tls your@email.address
+        try_files {path} {path}/index.php /index.php?{query}
+}
+```
+### Example configuration: Docker Compose + Traefik + Unbound (Raspberry Pi/Linux/Mac) [linux/amd64,linux/arm64,linux/arm/v7]
 
-    https://MY_SERVER_NAME {
+```yaml
-            log     / syslog "{remote} - {user} [{when}] \"{method} {scheme}://{host}{uri} {proto}\" {status} {size} \"{>Referer}\" \"{>User-Agent}\" {>X-Forwarded-For}"
+version: '2.2'
-            errors  syslog
+networks:
-            gzip
+  default:
-            proxy   /dns-query      http://[::1]:18053 {
+
-                    header_upstream Host {host}
+services:
-                    header_upstream X-Real-IP {remote}
+  proxy:
-                    header_upstream X-Forwarded-For {>X-Forwarded-For},{remote}
+    # The official v2 Traefik docker image
-                    header_upstream X-Forwarded-Proto {scheme}
+    image: traefik:v2.3
-            }
+    hostname: proxy
-            root    /var/www
+    networks:
-            tls {
+      - default
-                    ciphers ECDHE-ECDSA-WITH-CHACHA20-POLY1305 ECDHE-RSA-WITH-CHACHA20-POLY1305 ECDHE-ECDSA-AES256-GCM-SHA384 ECDHE-RSA-AES256-GCM-SHA384 ECDHE-ECDSA-AES128-GCM-SHA256 ECDHE-RSA-AES128-GCM-SHA256
+    environment:
-                    curves  X25519 p384 p521
+      TRAEFIK_ACCESSLOG: "true"
-                    must_staple
+      TRAEFIK_API: "true"
+      TRAEFIK_PROVIDERS_DOCKER: "true"
+      TRAEFIK_API_INSECURE: "true"
+      TRAEFIK_PROVIDERS_DOCKER_NETWORK: "${STACK}_default"
+      # DNS provider specific environment variables for DNS Challenge using route53 (AWS)
+      AWS_ACCESS_KEY_ID: ${AWS_ACCESS_KEY_ID}
+      AWS_SECRET_ACCESS_KEY: ${AWS_SECRET_ACCESS_KEY}
+      AWS_REGION: ${AWS_REGION}
+      AWS_HOSTED_ZONE_ID: ${AWS_HOSTED_ZONE_ID}
+    ports:
+      # The HTTP port
+      - "80:80"
+      # The HTTPS port
+      - "443:443"
+      # The Web UI (enabled by --api.insecure=true)
+      - "8080:8080"
+    command:
+      #- "--log.level=DEBUG"
+      - "--providers.docker.exposedbydefault=false"
+      - "--entrypoints.web.address=:80"
+      - "--entrypoints.websecure.address=:443"
+      - "--certificatesresolvers.letsencrypt.acme.dnschallenge=true"
+      # Providers list:
+      #  https://docs.traefik.io/https/acme/#providers
+      #  https://go-acme.github.io/lego/dns/
+      - "--certificatesresolvers.letsencrypt.acme.dnschallenge.provider=route53"
+      # Enable below line to use staging letsencrypt server.
+      #- "--certificatesresolvers.letsencrypt.acme.caserver=https://acme-staging-v02.api.letsencrypt.org/directory"
+      - "--certificatesresolvers.letsencrypt.acme.email=${EMAIL}"
+      - "--certificatesresolvers.letsencrypt.acme.storage=/certs/acme.json"
+    volumes:
+      # So that Traefik can listen to the Docker events
+      - /var/run/docker.sock:/var/run/docker.sock
+      - ./data/proxy/certs:/certs
+  doh-server:
+    image: satishweb/doh-server:latest
+    hostname: doh-server
+    networks:
+      - default
+    environment:
+      # Enable below line to see more logs
+      # DEBUG: "1"
+      UPSTREAM_DNS_SERVER: "udp:unbound:53"
+      DOH_HTTP_PREFIX: "${DOH_HTTP_PREFIX}"
+      DOH_SERVER_LISTEN: ":${DOH_SERVER_LISTEN}"
+      DOH_SERVER_TIMEOUT: "10"
+      DOH_SERVER_TRIES: "3"
+      DOH_SERVER_VERBOSE: "false"
+    #volumes:
+      # - ./doh-server.conf:/server/doh-server.conf
+      # - ./app-config:/app-config
+    depends_on:
+      - unbound
+    labels:
+      - "traefik.enable=true"
+      - "traefik.http.routers.doh-server.rule=Host(`${SUBDOMAIN}.${DOMAIN}`) && Path(`${DOH_HTTP_PREFIX}`)"
+      - "traefik.http.services.doh-server.loadbalancer.server.port=${DOH_SERVER_LISTEN}"
+      - "traefik.http.middlewares.mw-doh-compression.compress=true"
+      - "traefik.http.routers.doh-server.tls=true"
+      - "traefik.http.middlewares.mw-doh-tls.headers.sslredirect=true"
+      - "traefik.http.middlewares.mw-doh-tls.headers.sslforcehost=true"
+      - "traefik.http.routers.doh-server.tls.certresolver=letsencrypt"
+      - "traefik.http.routers.doh-server.tls.domains[0].main=${DOMAIN}"
+      - "traefik.http.routers.doh-server.tls.domains[0].sans=${SUBDOMAIN}.${DOMAIN}"
+      # Protection from requests flood
+      - "traefik.http.middlewares.mw-doh-ratelimit.ratelimit.average=100"
+      - "traefik.http.middlewares.mw-doh-ratelimit.ratelimit.burst=50"
+      - "traefik.http.middlewares.mw-doh-ratelimit.ratelimit.period=10s"
+  unbound:
+    image: satishweb/unbound:latest
+    hostname: unbound
+    networks:
+      - default
+    ports:
+      # Disable these ports if DOH server is the only client
+      - 53:53/tcp
+      - 53:53/udp
+    volumes:
+      - ./unbound.sample.conf:/templates/unbound.sample.conf
+      - ./data/unbound/custom:/etc/unbound/custom
+      # Keep your custom.hosts file inside custom folder
+    #environment:
+    #  DEBUG: "1"
+````
+
+> Complete Guide available at: https://github.com/satishweb/docker-doh
+
+> IPV6 Support for Docker Compose based configuration TBA
+
+### Example configuration: DNS-over-TLS
+
+There is no native [DNS-over-TLS](https://en.wikipedia.org/wiki/DNS_over_TLS) support but you can easily add it via nginx:
+```
+stream {
+    server {
+        listen                  *:853 ssl;
+        proxy_pass              ipofyourdnsresolver:port  #127.0.0.1:53
     }
+
+    ssl_certificate /etc/letsencrypt/live/site.yourdomain/fullchain.pem; 
+    ssl_certificate_key /etc/letsencrypt/live/site.yourdomain/privkey.pem; 
 }
+```
+
+The DoT service can also be provided by running a [STunnel](https://www.stunnel.org/) instance to wrap dnsmasq (or any other resolver of your choice, listening on a TCP port);
+this approach does not need a stand-alone daemon to provide the DoT service.
 
 ## DNSSEC
 
 DNS-over-HTTPS is compatible with DNSSEC, and requests DNSSEC signatures by
 default. However signature validation is not built-in. It is highly recommended
 that you install `unbound` or `bind` and pass results for them to validate DNS
-records.
+records. An instance of [Pi Hole](https://pi-hole.net) could also be used to validate DNS signatures as well as provide other capabilities.
 
 ## EDNS0-Client-Subnet (GeoDNS)
 

doh-client/client.go

@@ -25,6 +25,7 @@ package main
 
 import (
 	"context"
+	"crypto/tls"
 	"fmt"
 	"log"
 	"math/rand"
@@ -37,9 +38,9 @@ import (
 	"sync"
 	"time"
 
-	"github.com/m13253/dns-over-https/doh-client/config"
+	"github.com/m13253/dns-over-https/v2/doh-client/config"
-	"github.com/m13253/dns-over-https/doh-client/selector"
+	"github.com/m13253/dns-over-https/v2/doh-client/selector"
-	"github.com/m13253/dns-over-https/json-dns"
+	jsondns "github.com/m13253/dns-over-https/v2/json-dns"
 	"github.com/miekg/dns"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/idna"
@@ -247,6 +248,7 @@ func (c *Client) newHTTPClient() error {
 		MaxIdleConnsPerHost:   10,
 		Proxy:                 http.ProxyFromEnvironment,
 		TLSHandshakeTimeout:   time.Duration(c.conf.Other.Timeout) * time.Second,
+		TLSClientConfig:       &tls.Config{InsecureSkipVerify: c.conf.Other.TLSInsecureSkipVerify},
 	}
 	if c.conf.Other.NoIPv6 {
 		c.httpTransport.DialContext = func(ctx context.Context, network, address string) (net.Conn, error) {
@@ -305,7 +307,7 @@ func (c *Client) handlerFunc(w dns.ResponseWriter, r *dns.Msg, isTCP bool) {
 
 	if len(r.Question) != 1 {
 		log.Println("Number of questions is not 1")
-		reply := jsonDNS.PrepareReply(r)
+		reply := jsondns.PrepareReply(r)
 		reply.Rcode = dns.RcodeFormatError
 		w.WriteMsg(reply)
 		return
@@ -356,7 +358,7 @@ func (c *Client) handlerFunc(w dns.ResponseWriter, r *dns.Msg, isTCP bool) {
 			return
 		}
 		log.Println(err)
-		reply = jsonDNS.PrepareReply(r)
+		reply = jsondns.PrepareReply(r)
 		reply.Rcode = dns.RcodeServerFailure
 		w.WriteMsg(reply)
 		return
@@ -471,7 +473,7 @@ func (c *Client) findClientIP(w dns.ResponseWriter, r *dns.Msg) (ednsClientAddre
 	if err != nil {
 		return
 	}
-	if ip := remoteAddr.IP; jsonDNS.IsGlobalIP(ip) {
+	if ip := remoteAddr.IP; jsondns.IsGlobalIP(ip) {
 		if ipv4 := ip.To4(); ipv4 != nil {
 			ednsClientAddress = ipv4.Mask(ipv4Mask24)
 			ednsClientNetmask = 24

doh-client/config/config.go

@@ -56,6 +56,7 @@ type others struct {
 	NoUserAgent           bool     `toml:"no_user_agent"`
 	Verbose               bool     `toml:"verbose"`
 	DebugHTTPHeaders      []string `toml:"debug_http_headers"`
+	TLSInsecureSkipVerify bool     `toml:"insecure_tls_skip_verify"`
 }
 
 type Config struct {

doh-client/doh-client.conf

@@ -64,7 +64,7 @@ upstream_selector = "random"
 # bootstrap server, please make this list empty.
 bootstrap = [
 
-    # Google's resolver, bad ECS, good DNSSEC
+    # Google's resolver, good ECS, good DNSSEC
     "8.8.8.8:53",
     "8.8.4.4:53",
 
@@ -132,3 +132,9 @@ no_user_agent = false
 
 # Enable logging
 verbose = false
+
+# insecure_tls_skip_verification will disable necessary TLS security verification.
+# This option is designed for testing or development purposes,
+# turning on this option on public Internet may cause your connection
+# vulnerable to MITM attack.
+insecure_tls_skip_verify = false

doh-client/google.go

@@ -34,8 +34,8 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/m13253/dns-over-https/doh-client/selector"
+	"github.com/m13253/dns-over-https/v2/doh-client/selector"
-	"github.com/m13253/dns-over-https/json-dns"
+	jsondns "github.com/m13253/dns-over-https/v2/json-dns"
 	"github.com/miekg/dns"
 )
 
@@ -44,7 +44,7 @@ func (c *Client) generateRequestGoogle(ctx context.Context, w dns.ResponseWriter
 	questionName := question.Name
 	questionClass := question.Qclass
 	if questionClass != dns.ClassINET {
-		reply := jsonDNS.PrepareReply(r)
+		reply := jsondns.PrepareReply(r)
 		reply.Rcode = dns.RcodeRefused
 		w.WriteMsg(reply)
 		return &DNSRequest{
@@ -67,6 +67,9 @@ func (c *Client) generateRequestGoogle(ctx context.Context, w dns.ResponseWriter
 	udpSize := uint16(512)
 	if opt := r.IsEdns0(); opt != nil {
 		udpSize = opt.UDPSize()
+		if opt.Do() {
+			requestURL += "&do=1"
+		}
 	}
 
 	ednsClientAddress, ednsClientNetmask := c.findClientIP(w, r)
@@ -77,7 +80,7 @@ func (c *Client) generateRequestGoogle(ctx context.Context, w dns.ResponseWriter
 	req, err := http.NewRequest(http.MethodGet, requestURL, nil)
 	if err != nil {
 		log.Println(err)
-		reply := jsonDNS.PrepareReply(r)
+		reply := jsondns.PrepareReply(r)
 		reply.Rcode = dns.RcodeServerFailure
 		w.WriteMsg(reply)
 		return &DNSRequest{
@@ -108,7 +111,7 @@ func (c *Client) generateRequestGoogle(ctx context.Context, w dns.ResponseWriter
 
 	if err != nil {
 		log.Println(err)
-		reply := jsonDNS.PrepareReply(r)
+		reply := jsondns.PrepareReply(r)
 		reply.Rcode = dns.RcodeServerFailure
 		w.WriteMsg(reply)
 		return &DNSRequest{
@@ -118,7 +121,7 @@ func (c *Client) generateRequestGoogle(ctx context.Context, w dns.ResponseWriter
 
 	return &DNSRequest{
 		response:          resp,
-		reply:             jsonDNS.PrepareReply(r),
+		reply:             jsondns.PrepareReply(r),
 		udpSize:           udpSize,
 		ednsClientAddress: ednsClientAddress,
 		ednsClientNetmask: ednsClientNetmask,
@@ -145,7 +148,7 @@ func (c *Client) parseResponseGoogle(ctx context.Context, w dns.ResponseWriter,
 		return
 	}
 
-	var respJSON jsonDNS.Response
+	var respJSON jsondns.Response
 	err = json.Unmarshal(body, &respJSON)
 	if err != nil {
 		log.Println(err)
@@ -157,8 +160,9 @@ func (c *Client) parseResponseGoogle(ctx context.Context, w dns.ResponseWriter,
 	if respJSON.Status != dns.RcodeSuccess && respJSON.Comment != "" {
 		log.Printf("DNS error: %s\n", respJSON.Comment)
 	}
+	fixEmptyNames(&respJSON)
 
-	fullReply := jsonDNS.Unmarshal(req.reply, &respJSON, req.udpSize, req.ednsClientNetmask)
+	fullReply := jsondns.Unmarshal(req.reply, &respJSON, req.udpSize, req.ednsClientNetmask)
 	buf, err := fullReply.Pack()
 	if err != nil {
 		log.Println(err)
@@ -177,3 +181,19 @@ func (c *Client) parseResponseGoogle(ctx context.Context, w dns.ResponseWriter,
 	}
 	w.Write(buf)
 }
+
+// Fix DNS response empty []RR.Name
+// Additional section won't be rectified
+// see: https://stackoverflow.com/questions/52136176/what-is-additional-section-in-dns-and-how-it-works
+func fixEmptyNames(respJSON *jsondns.Response) {
+	for i := range respJSON.Answer {
+		if respJSON.Answer[i].Name == "" {
+			respJSON.Answer[i].Name = "."
+		}
+	}
+	for i := range respJSON.Authority {
+		if respJSON.Authority[i].Name == "" {
+			respJSON.Authority[i].Name = "."
+		}
+	}
+}

doh-client/ietf.go

@@ -35,8 +35,8 @@ import (
 	"strings"
 	"time"
 
-	"github.com/m13253/dns-over-https/doh-client/selector"
+	"github.com/m13253/dns-over-https/v2/doh-client/selector"
-	jsonDNS "github.com/m13253/dns-over-https/json-dns"
+	jsondns "github.com/m13253/dns-over-https/v2/json-dns"
 	"github.com/miekg/dns"
 )
 
@@ -90,7 +90,7 @@ func (c *Client) generateRequestIETF(ctx context.Context, w dns.ResponseWriter,
 	requestBinary, err := r.Pack()
 	if err != nil {
 		log.Println(err)
-		reply := jsonDNS.PrepareReply(r)
+		reply := jsondns.PrepareReply(r)
 		reply.Rcode = dns.RcodeFormatError
 		w.WriteMsg(reply)
 		return &DNSRequest{
@@ -107,7 +107,7 @@ func (c *Client) generateRequestIETF(ctx context.Context, w dns.ResponseWriter,
 		req, err = http.NewRequest(http.MethodGet, requestURL, nil)
 		if err != nil {
 			log.Println(err)
-			reply := jsonDNS.PrepareReply(r)
+			reply := jsondns.PrepareReply(r)
 			reply.Rcode = dns.RcodeServerFailure
 			w.WriteMsg(reply)
 			return &DNSRequest{
@@ -118,7 +118,7 @@ func (c *Client) generateRequestIETF(ctx context.Context, w dns.ResponseWriter,
 		req, err = http.NewRequest(http.MethodPost, upstream.URL, bytes.NewReader(requestBinary))
 		if err != nil {
 			log.Println(err)
-			reply := jsonDNS.PrepareReply(r)
+			reply := jsondns.PrepareReply(r)
 			reply.Rcode = dns.RcodeServerFailure
 			w.WriteMsg(reply)
 			return &DNSRequest{
@@ -149,7 +149,7 @@ func (c *Client) generateRequestIETF(ctx context.Context, w dns.ResponseWriter,
 
 	if err != nil {
 		log.Println(err)
-		reply := jsonDNS.PrepareReply(r)
+		reply := jsondns.PrepareReply(r)
 		reply.Rcode = dns.RcodeServerFailure
 		w.WriteMsg(reply)
 		return &DNSRequest{
@@ -159,7 +159,7 @@ func (c *Client) generateRequestIETF(ctx context.Context, w dns.ResponseWriter,
 
 	return &DNSRequest{
 		response:          resp,
-		reply:             jsonDNS.PrepareReply(r),
+		reply:             jsondns.PrepareReply(r),
 		udpSize:           udpSize,
 		ednsClientAddress: ednsClientAddress,
 		ednsClientNetmask: ednsClientNetmask,

doh-client/main.go

@@ -33,7 +33,7 @@ import (
 	"runtime"
 	"strconv"
 
-	"github.com/m13253/dns-over-https/doh-client/config"
+	"github.com/m13253/dns-over-https/v2/doh-client/config"
 )
 
 func checkPIDFile(pidFile string) (bool, error) {

doh-client/version.go

@@ -24,6 +24,6 @@
 package main
 
 const (
-	VERSION    = "2.2.1"
+	VERSION    = "2.3.2"
 	USER_AGENT = "DNS-over-HTTPS/" + VERSION + " (+https://github.com/m13253/dns-over-https)"
 )

doh-server/config.go

@@ -42,6 +42,10 @@ type config struct {
 	Verbose             bool     `toml:"verbose"`
 	DebugHTTPHeaders    []string `toml:"debug_http_headers"`
 	LogGuessedIP        bool     `toml:"log_guessed_client_ip"`
+	ECSAllowNonGlobalIP bool     `toml:"ecs_allow_non_global_ip"`
+	ECSUsePreciseIP     bool     `toml:"ecs_use_precise_ip"`
+	TLSClientAuth       bool     `toml:"tls_client_auth"`
+	TLSClientAuthCA     string   `toml:"tls_client_auth_ca"`
 }
 
 func loadConfig(path string) (*config, error) {

doh-server/doh-server.conf

@@ -51,3 +51,28 @@ verbose = false
 # Enable log IP from HTTPS-reverse proxy header: X-Forwarded-For or X-Real-IP
 # Note: http uri/useragent log cannot be controlled by this config
 log_guessed_client_ip = false
+
+# By default, non global IP addresses are never forwarded to upstream servers.
+# This is to prevent two things from happening:
+#   1. the upstream server knowing your private LAN addresses;
+#   2. the upstream server unable to provide geographically near results,
+#      or even fail to provide any result.
+# However, if you are deploying a split tunnel corporation network
+# environment, or for any other reason you want to inhibit this
+# behavior and allow local (eg RFC1918) address to be forwarded,
+# change the following option to "true".
+ecs_allow_non_global_ip = false
+
+# If ECS is added to the request, let the full IP address or
+# cap it to 24 or 128 mask. This option is to be used only on private
+# networks where knwoledge of the terminal endpoint may be required for
+# security purposes (eg. DNS Firewalling). Not a good option on the
+# internet where IP address may be used to identify the user and
+# not only the approximate location.
+ecs_use_precise_ip = false
+
+# If DOH is used for a controlled network, it is possible to enable
+# the client TLS certificate validation with a specific certificate
+# authority used to sign any client one. Disabled by default.
+# tls_client_auth = true
+# tls_client_auth_ca = "root-ca-public.crt"

doh-server/google.go

@@ -34,7 +34,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/m13253/dns-over-https/json-dns"
+	jsondns "github.com/m13253/dns-over-https/v2/json-dns"
 	"github.com/miekg/dns"
 	"golang.org/x/net/idna"
 )
@@ -170,11 +170,11 @@ func (s *Server) parseRequestGoogle(ctx context.Context, w http.ResponseWriter,
 }
 
 func (s *Server) generateResponseGoogle(ctx context.Context, w http.ResponseWriter, r *http.Request, req *DNSRequest) {
-	respJSON := jsonDNS.Marshal(req.response)
+	respJSON := jsondns.Marshal(req.response)
 	respStr, err := json.Marshal(respJSON)
 	if err != nil {
 		log.Println(err)
-		jsonDNS.FormatError(w, fmt.Sprintf("DNS packet parse failure (%s)", err.Error()), 500)
+		jsondns.FormatError(w, fmt.Sprintf("DNS packet parse failure (%s)", err.Error()), 500)
 		return
 	}
 

doh-server/ietf.go

@@ -36,7 +36,7 @@ import (
 	"strings"
 	"time"
 
-	jsonDNS "github.com/m13253/dns-over-https/json-dns"
+	jsondns "github.com/m13253/dns-over-https/v2/json-dns"
 	"github.com/miekg/dns"
 )
 
@@ -125,6 +125,7 @@ func (s *Server) parseRequestIETF(ctx context.Context, w http.ResponseWriter, r
 		}
 	}
 	isTailored := edns0Subnet == nil
+
 	if edns0Subnet == nil {
 		ednsClientFamily := uint16(0)
 		ednsClientAddress := s.findClientIP(r)
@@ -133,10 +134,20 @@ func (s *Server) parseRequestIETF(ctx context.Context, w http.ResponseWriter, r
 			if ipv4 := ednsClientAddress.To4(); ipv4 != nil {
 				ednsClientFamily = 1
 				ednsClientAddress = ipv4
+				if s.conf.ECSUsePreciseIP {
+					ednsClientNetmask = 32
+				} else {
 					ednsClientNetmask = 24
+					ednsClientAddress = ednsClientAddress.Mask(net.CIDRMask(24, 32))
+				}
 			} else {
 				ednsClientFamily = 2
+				if s.conf.ECSUsePreciseIP {
+					ednsClientNetmask = 128
+				} else {
 					ednsClientNetmask = 56
+					ednsClientAddress = ednsClientAddress.Mask(net.CIDRMask(56, 128))
+				}
 			}
 			edns0Subnet = new(dns.EDNS0_SUBNET)
 			edns0Subnet.Code = dns.EDNS0SUBNET
@@ -156,12 +167,12 @@ func (s *Server) parseRequestIETF(ctx context.Context, w http.ResponseWriter, r
 }
 
 func (s *Server) generateResponseIETF(ctx context.Context, w http.ResponseWriter, r *http.Request, req *DNSRequest) {
-	respJSON := jsonDNS.Marshal(req.response)
+	respJSON := jsondns.Marshal(req.response)
 	req.response.Id = req.transactionID
 	respBytes, err := req.response.Pack()
 	if err != nil {
 		log.Printf("DNS packet construct failure with upstream %s: %v\n", req.currentUpstream, err)
-		jsonDNS.FormatError(w, fmt.Sprintf("DNS packet construct failure (%s)", err.Error()), 500)
+		jsondns.FormatError(w, fmt.Sprintf("DNS packet construct failure (%s)", err.Error()), 500)
 		return
 	}
 
@@ -195,7 +206,9 @@ func (s *Server) generateResponseIETF(ctx context.Context, w http.ResponseWriter
 // Workaround a bug causing DNSCrypt-Proxy to expect a response with TransactionID = 0xcafe
 func (s *Server) patchDNSCryptProxyReqID(w http.ResponseWriter, r *http.Request, requestBinary []byte) bool {
 	if strings.Contains(r.UserAgent(), "dnscrypt-proxy") && bytes.Equal(requestBinary, []byte("\xca\xfe\x01\x00\x00\x01\x00\x00\x00\x00\x00\x01\x00\x00\x02\x00\x01\x00\x00\x29\x10\x00\x00\x00\x80\x00\x00\x00")) {
+		if s.conf.Verbose {
 			log.Println("DNSCrypt-Proxy detected. Patching response.")
+		}
 		w.Header().Set("Content-Type", "application/dns-message")
 		w.Header().Set("Vary", "Accept, User-Agent")
 		now := time.Now().UTC().Format(http.TimeFormat)
@@ -209,7 +222,9 @@ func (s *Server) patchDNSCryptProxyReqID(w http.ResponseWriter, r *http.Request,
 // Workaround a bug causing Firefox 61-62 to reject responses with Content-Type = application/dns-message
 func (s *Server) patchFirefoxContentType(w http.ResponseWriter, r *http.Request, req *DNSRequest) bool {
 	if strings.Contains(r.UserAgent(), "Firefox") && strings.Contains(r.Header.Get("Accept"), "application/dns-udpwireformat") && !strings.Contains(r.Header.Get("Accept"), "application/dns-message") {
+		if s.conf.Verbose {
 			log.Println("Firefox 61-62 detected. Patching response.")
+		}
 		w.Header().Set("Content-Type", "application/dns-udpwireformat")
 		w.Header().Set("Vary", "Accept, User-Agent")
 		req.isTailored = true

doh-server/server.go

@@ -25,7 +25,10 @@ package main
 
 import (
 	"context"
+	"crypto/tls"
+	"crypto/x509"
 	"fmt"
+	"io/ioutil"
 	"log"
 	"math/rand"
 	"net"
@@ -35,7 +38,7 @@ import (
 	"time"
 
 	"github.com/gorilla/handlers"
-	jsonDNS "github.com/m13253/dns-over-https/json-dns"
+	jsondns "github.com/m13253/dns-over-https/v2/json-dns"
 	"github.com/miekg/dns"
 )
 
@@ -107,12 +110,48 @@ func (s *Server) Start() error {
 	if s.conf.Verbose {
 		servemux = handlers.CombinedLoggingHandler(os.Stdout, servemux)
 	}
+
+	var clientCAPool *x509.CertPool
+	if s.conf.TLSClientAuth {
+		if s.conf.TLSClientAuthCA != "" {
+			clientCA, err := ioutil.ReadFile(s.conf.TLSClientAuthCA)
+			if err != nil {
+				log.Fatalf("Reading certificate for client authentication has failed: %v", err)
+			}
+			clientCAPool = x509.NewCertPool()
+			clientCAPool.AppendCertsFromPEM(clientCA)
+			log.Println("Certificate loaded for client TLS authentication")
+		} else {
+			log.Fatalln("TLS client authentication requires both tls_client_auth and tls_client_auth_ca, exiting.")
+		}
+	}
+
 	results := make(chan error, len(s.conf.Listen))
 	for _, addr := range s.conf.Listen {
 		go func(addr string) {
 			var err error
 			if s.conf.Cert != "" || s.conf.Key != "" {
+				if clientCAPool != nil {
+					srvtls := &http.Server{
+						Handler: servemux,
+						Addr:    addr,
+						TLSConfig: &tls.Config{
+							ClientCAs:  clientCAPool,
+							ClientAuth: tls.RequireAndVerifyClientCert,
+							GetCertificate: func(info *tls.ClientHelloInfo) (certificate *tls.Certificate, e error) {
+								c, err := tls.LoadX509KeyPair(s.conf.Cert, s.conf.Key)
+								if err != nil {
+									fmt.Printf("Error loading server certificate key pair: %v\n", err)
+									return nil, err
+								}
+								return &c, nil
+							},
+						},
+					}
+					err = srvtls.ListenAndServeTLS("", "")
+				} else {
 					err = http.ListenAndServeTLS(addr, s.conf.Cert, s.conf.Key, servemux)
+				}
 			} else {
 				err = http.ListenAndServe(addr, servemux)
 			}
@@ -136,6 +175,18 @@ func (s *Server) Start() error {
 func (s *Server) handlerFunc(w http.ResponseWriter, r *http.Request) {
 	ctx := r.Context()
 
+	if realIP := r.Header.Get("X-Real-IP"); realIP != "" {
+		if strings.ContainsRune(realIP, ':') {
+			r.RemoteAddr = "[" + realIP + "]:0"
+		} else {
+			r.RemoteAddr = realIP + ":0"
+		}
+		_, _, err := net.SplitHostPort(r.RemoteAddr)
+		if err != nil {
+			r.RemoteAddr = realIP
+		}
+	}
+
 	w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
 	w.Header().Set("Access-Control-Allow-Methods", "GET, HEAD, OPTIONS, POST")
 	w.Header().Set("Access-Control-Allow-Origin", "*")
@@ -204,23 +255,22 @@ func (s *Server) handlerFunc(w http.ResponseWriter, r *http.Request) {
 	} else if contentType == "application/dns-udpwireformat" {
 		req = s.parseRequestIETF(ctx, w, r)
 	} else {
-		jsonDNS.FormatError(w, fmt.Sprintf("Invalid argument value: \"ct\" = %q", contentType), 415)
+		jsondns.FormatError(w, fmt.Sprintf("Invalid argument value: \"ct\" = %q", contentType), 415)
 		return
 	}
 	if req.errcode == 444 {
 		return
 	}
 	if req.errcode != 0 {
-		jsonDNS.FormatError(w, req.errtext, req.errcode)
+		jsondns.FormatError(w, req.errtext, req.errcode)
 		return
 	}
 
 	req = s.patchRootRD(req)
 
-	var err error
+	err := s.doDNSQuery(ctx, req)
-	req, err = s.doDNSQuery(ctx, req)
 	if err != nil {
-		jsonDNS.FormatError(w, fmt.Sprintf("DNS query failure (%s)", err.Error()), 503)
+		jsondns.FormatError(w, fmt.Sprintf("DNS query failure (%s)", err.Error()), 503)
 		return
 	}
 
@@ -234,12 +284,17 @@ func (s *Server) handlerFunc(w http.ResponseWriter, r *http.Request) {
 }
 
 func (s *Server) findClientIP(r *http.Request) net.IP {
+	noEcs := r.URL.Query().Get("no_ecs")
+	if strings.ToLower(noEcs) == "true" {
+		return nil
+	}
+
 	XForwardedFor := r.Header.Get("X-Forwarded-For")
 	if XForwardedFor != "" {
 		for _, addr := range strings.Split(XForwardedFor, ",") {
 			addr = strings.TrimSpace(addr)
 			ip := net.ParseIP(addr)
-			if jsonDNS.IsGlobalIP(ip) {
+			if jsondns.IsGlobalIP(ip) {
 				return ip
 			}
 		}
@@ -248,15 +303,17 @@ func (s *Server) findClientIP(r *http.Request) net.IP {
 	if XRealIP != "" {
 		addr := strings.TrimSpace(XRealIP)
 		ip := net.ParseIP(addr)
-		if jsonDNS.IsGlobalIP(ip) {
+		if s.conf.ECSAllowNonGlobalIP || jsondns.IsGlobalIP(ip) {
 			return ip
 		}
 	}
+
 	remoteAddr, err := net.ResolveTCPAddr("tcp", r.RemoteAddr)
 	if err != nil {
 		return nil
 	}
-	if ip := remoteAddr.IP; jsonDNS.IsGlobalIP(ip) {
+	ip := remoteAddr.IP
+	if s.conf.ECSAllowNonGlobalIP || jsondns.IsGlobalIP(ip) {
 		return ip
 	}
 	return nil
@@ -282,8 +339,7 @@ func (s *Server) indexQuestionType(msg *dns.Msg, qtype uint16) int {
 	return -1
 }
 
-func (s *Server) doDNSQuery(ctx context.Context, req *DNSRequest) (resp *DNSRequest, err error) {
+func (s *Server) doDNSQuery(ctx context.Context, req *DNSRequest) (err error) {
-	// TODO(m13253): Make ctx work. Waiting for a patch for ExchangeContext from miekg/dns.
 	numServers := len(s.conf.Upstream)
 	for i := uint(0); i < s.conf.Tries; i++ {
 		req.currentUpstream = s.conf.Upstream[rand.Intn(numServers)]
@@ -293,34 +349,34 @@ func (s *Server) doDNSQuery(ctx context.Context, req *DNSRequest) (resp *DNSRequ
 		switch t {
 		default:
 			log.Printf("invalid DNS type %q in upstream %q", t, upstream)
-			return nil, &configError{"invalid DNS type"}
+			return &configError{"invalid DNS type"}
 		// Use DNS-over-TLS (DoT) if configured to do so
 		case "tcp-tls":
-			req.response, _, err = s.tcpClientTLS.Exchange(req.request, upstream)
+			req.response, _, err = s.tcpClientTLS.ExchangeContext(ctx, req.request, upstream)
 		case "tcp", "udp":
 			// Use TCP if always configured to or if the Query type dictates it (AXFR)
 			if t == "tcp" || (s.indexQuestionType(req.request, dns.TypeAXFR) > -1) {
-				req.response, _, err = s.tcpClient.Exchange(req.request, upstream)
+				req.response, _, err = s.tcpClient.ExchangeContext(ctx, req.request, upstream)
 			} else {
-				req.response, _, err = s.udpClient.Exchange(req.request, upstream)
+				req.response, _, err = s.udpClient.ExchangeContext(ctx, req.request, upstream)
 				if err == nil && req.response != nil && req.response.Truncated {
 					log.Println(err)
-					req.response, _, err = s.tcpClient.Exchange(req.request, upstream)
+					req.response, _, err = s.tcpClient.ExchangeContext(ctx, req.request, upstream)
 				}
 
 				// Retry with TCP if this was an IXFR request and we only received an SOA
 				if (s.indexQuestionType(req.request, dns.TypeIXFR) > -1) &&
 					(len(req.response.Answer) == 1) &&
 					(req.response.Answer[0].Header().Rrtype == dns.TypeSOA) {
-					req.response, _, err = s.tcpClient.Exchange(req.request, upstream)
+					req.response, _, err = s.tcpClient.ExchangeContext(ctx, req.request, upstream)
 				}
 			}
 		}
 
 		if err == nil {
-			return req, nil
+			return nil
 		}
 		log.Printf("DNS error from upstream %s: %s\n", req.currentUpstream, err.Error())
 	}
-	return req, err
+	return err
 }

doh-server/version.go

@@ -24,6 +24,6 @@
 package main
 
 const (
-	VERSION    = "2.2.1"
+	VERSION    = "2.3.2"
 	USER_AGENT = "DNS-over-HTTPS/" + VERSION + " (+https://github.com/m13253/dns-over-https)"
 )

go.mod

@@ -1,12 +1,20 @@
-module github.com/m13253/dns-over-https
+module github.com/m13253/dns-over-https/v2
 
-go 1.12
+go 1.19
 
 require (
-	github.com/BurntSushi/toml v0.3.1
+	github.com/BurntSushi/toml v1.2.0
-	github.com/gorilla/handlers v1.4.0
+	github.com/gorilla/handlers v1.5.1
-	github.com/miekg/dns v1.1.22
+	github.com/infobloxopen/go-trees v0.0.0-20200715205103-96a057b8dfb9
-	golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 // indirect
+	github.com/miekg/dns v1.1.50
-	golang.org/x/net v0.0.0-20191027093000-83d349e8ac1a
+	golang.org/x/net v0.0.0-20220812174116-3211cb980234
-	golang.org/x/sys v0.0.0-20191026070338-33540a1f6037 // indirect
+)
+
+require (
+	github.com/felixge/httpsnoop v1.0.1 // indirect
+	golang.org/x/mod v0.4.2 // indirect
+	golang.org/x/sys v0.0.0-20220728004956-3c1f35247d10 // indirect
+	golang.org/x/text v0.3.7 // indirect
+	golang.org/x/tools v0.1.6-0.20210726203631-07bc1bf47fb2 // indirect
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 )

go.sum

@@ -1,36 +1,51 @@
-github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
+github.com/BurntSushi/toml v1.2.0 h1:Rt8g24XnyGTyglgET/PRUNlrUeu9F5L+7FilkXfZgs0=
-github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/BurntSushi/toml v1.2.0/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
-github.com/gorilla/handlers v1.4.0 h1:XulKRWSQK5uChr4pEgSE4Tc/OcmnU9GJuSwdog/tZsA=
+github.com/felixge/httpsnoop v1.0.1 h1:lvB5Jl89CsZtGIWuTcDM1E/vkVs49/Ml7JJe07l8SPQ=
-github.com/gorilla/handlers v1.4.0/go.mod h1:Qkdc/uu4tH4g6mTK6auzZ766c4CA0Ng8+o/OAirnOIQ=
+github.com/felixge/httpsnoop v1.0.1/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
-github.com/miekg/dns v1.1.14 h1:wkQWn9wIp4mZbwW8XV6Km6owkvRPbOiV004ZM2CkGvA=
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 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
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 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
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-golang.org/x/net v0.0.0-20191027093000-83d349e8ac1a h1:Yu34BogBivvmu7SAzHHaB9nZWH5D1C+z3F1jyIaYZSQ=
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 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
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+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
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json-dns/error.go

@@ -21,7 +21,7 @@
    DEALINGS IN THE SOFTWARE.
 */
 
-package jsonDNS
+package jsondns
 
 import (
 	"encoding/json"
@@ -38,11 +38,11 @@ type dnsError struct {
 
 func FormatError(w http.ResponseWriter, comment string, errcode int) {
 	w.Header().Set("Content-Type", "application/json; charset=UTF-8")
-	errJson := dnsError{
+	errJSON := dnsError{
 		Status:  dns.RcodeServerFailure,
 		Comment: comment,
 	}
-	errStr, err := json.Marshal(errJson)
+	errStr, err := json.Marshal(errJSON)
 	if err != nil {
 		log.Fatalln(err)
 	}

json-dns/globalip.go

@@ -21,109 +21,111 @@
    DEALINGS IN THE SOFTWARE.
 */
 
-package jsonDNS
+package jsondns
 
 import (
 	"net"
+
+	"github.com/infobloxopen/go-trees/iptree"
 )
 
-// RFC6890
+var defaultFilter *iptree.Tree
-var localIPv4Nets = []net.IPNet{
+
-	// This host on this network
+func init() {
-	net.IPNet{
+	defaultFilter = iptree.NewTree()
-		net.IP{0, 0, 0, 0},
+
-		net.IPMask{255, 0, 0, 0},
+	// RFC6890
-	},
+	// This host on this network
-	// Private-Use Networks
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-	net.IPNet{
+		IP:   net.IP{0, 0, 0, 0},
-		net.IP{10, 0, 0, 0},
+		Mask: net.IPMask{255, 0, 0, 0},
-		net.IPMask{255, 0, 0, 0},
+	}, struct{}{})
-	},
+
-	// Shared Address Space
+	// Private-Use Networks
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-		net.IP{100, 64, 0, 0},
+		IP:   net.IP{10, 0, 0, 0},
-		net.IPMask{255, 192, 0, 0},
+		Mask: net.IPMask{255, 0, 0, 0},
-	},
+	}, struct{}{})
-	// Loopback
+
-	net.IPNet{
+	// Shared Address Space
-		net.IP{127, 0, 0, 0},
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-		net.IPMask{255, 0, 0, 0},
+		IP:   net.IP{100, 64, 0, 0},
-	},
+		Mask: net.IPMask{255, 192, 0, 0},
-	// Link Local
+	}, struct{}{})
-	net.IPNet{
+
-		net.IP{169, 254, 0, 0},
+	// Loopback
-		net.IPMask{255, 255, 0, 0},
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-	},
+		IP:   net.IP{127, 0, 0, 0},
-	// Private-Use Networks
+		Mask: net.IPMask{255, 0, 0, 0},
-	net.IPNet{
+	}, struct{}{})
-		net.IP{172, 16, 0, 0},
+
-		net.IPMask{255, 240, 0, 0},
+	// Link Local
-	},
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-	// DS-Lite
+		IP:   net.IP{169, 254, 0, 0},
-	net.IPNet{
+		Mask: net.IPMask{255, 255, 0, 0},
-		net.IP{192, 0, 0, 0},
+	}, struct{}{})
-		net.IPMask{255, 255, 255, 248},
+
-	},
+	// Private-Use Networks
-	// 6to4 Relay Anycast
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-	net.IPNet{
+		IP:   net.IP{172, 16, 0, 0},
-		net.IP{192, 88, 99, 0},
+		Mask: net.IPMask{255, 240, 0, 0},
-		net.IPMask{255, 255, 255, 0},
+	}, struct{}{})
-	},
+
-	// Private-Use Networks
+	// DS-Lite
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-		net.IP{192, 168, 0, 0},
+		IP:   net.IP{192, 0, 0, 0},
-		net.IPMask{255, 255, 0, 0},
+		Mask: net.IPMask{255, 255, 255, 248},
-	},
+	}, struct{}{})
-	// Reserved for Future Use & Limited Broadcast
+
-	net.IPNet{
+	// 6to4 Relay Anycast
-		net.IP{240, 0, 0, 0},
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-		net.IPMask{240, 0, 0, 0},
+		IP:   net.IP{192, 88, 99, 0},
-	},
+		Mask: net.IPMask{255, 255, 255, 0},
-}
+	}, struct{}{})
+
+	// Private-Use Networks
+	defaultFilter.InplaceInsertNet(&net.IPNet{
+		IP:   net.IP{192, 168, 0, 0},
+		Mask: net.IPMask{255, 255, 0, 0},
+	}, struct{}{})
+
+	// Reserved for Future Use & Limited Broadcast
+	defaultFilter.InplaceInsertNet(&net.IPNet{
+		IP:   net.IP{240, 0, 0, 0},
+		Mask: net.IPMask{240, 0, 0, 0},
+	}, struct{}{})
 
 	// RFC6890
-var localIPv6Nets = []net.IPNet{
 	// Unspecified & Loopback Address
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-		net.IP{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		IP:   net.IP{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-		net.IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe},
+		Mask: net.IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe},
-	},
+	}, struct{}{})
+
 	// Discard-Only Prefix
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-		net.IP{0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		IP:   net.IP{0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-		net.IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		Mask: net.IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-	},
+	}, struct{}{})
+
 	// Unique-Local
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-		net.IP{0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		IP:   net.IP{0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-		net.IPMask{0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		Mask: net.IPMask{0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-	},
+	}, struct{}{})
+
 	// Linked-Scoped Unicast
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
-		net.IP{0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		IP:   net.IP{0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-		net.IPMask{0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		Mask: net.IPMask{0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-	},
+	}, struct{}{})
+
 }
 
 func IsGlobalIP(ip net.IP) bool {
 	if ip == nil {
 		return false
 	}
-	if ipv4 := ip.To4(); len(ipv4) == net.IPv4len {
+	_, contained := defaultFilter.GetByIP(ip)
-		for _, ipnet := range localIPv4Nets {
+	return !contained
-			if ipnet.Contains(ip) {
-				return false
-			}
-		}
-		return true
-	}
-	if len(ip) == net.IPv6len {
-		for _, ipnet := range localIPv6Nets {
-			if ipnet.Contains(ip) {
-				return false
-			}
-		}
-		return true
-	}
-	return true
 }

json-dns/globalip_test.go

@@ -0,0 +1,34 @@
+package jsondns
+
+import (
+	"fmt"
+	"net"
+)
+
+func ExampleIsGlobalIP() {
+	fmt.Println(IsGlobalIP(net.ParseIP("127.0.0.1")))
+	fmt.Println(IsGlobalIP(net.IP{192, 168, 1, 1}))
+	fmt.Println(IsGlobalIP(net.ParseIP("8.8.8.8")))
+	fmt.Println(IsGlobalIP(net.IP{8, 8, 4, 4}))
+	fmt.Println(IsGlobalIP(net.ParseIP("::1")))
+	fmt.Println(IsGlobalIP(net.IP{0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}))
+	fmt.Println(IsGlobalIP(net.ParseIP("2001:4860:4860::8888")))
+	fmt.Println(IsGlobalIP(net.IP{0x20, 0x01, 0x48, 0x60, 0x48, 0x60, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x88, 0x44}))
+	fmt.Println(IsGlobalIP(net.ParseIP("::ffff:127.0.0.1")))
+	fmt.Println(IsGlobalIP(net.IP{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 192, 168, 1, 1}))
+	fmt.Println(IsGlobalIP(net.ParseIP("::ffff:808:808")))
+	fmt.Println(IsGlobalIP(net.IP{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 8, 8, 4, 4}))
+	// Output:
+	// false
+	// false
+	// true
+	// true
+	// false
+	// false
+	// true
+	// true
+	// false
+	// false
+	// true
+	// true
+}

json-dns/marshal.go

@@ -21,7 +21,7 @@
    DEALINGS IN THE SOFTWARE.
 */
 
-package jsonDNS
+package jsondns
 
 import (
 	"net"

json-dns/response.go

@@ -21,12 +21,32 @@
    DEALINGS IN THE SOFTWARE.
 */
 
-package jsonDNS
+package jsondns
 
 import (
+	"encoding/json"
 	"time"
 )
 
+type QuestionList []Question
+
+func (ql *QuestionList) UnmarshalJSON(b []byte) error {
+	// Fix variant question response in Response.Question
+	//
+	// Solution taken from:
+	//	https://engineering.bitnami.com/articles/dealing-with-json-with-non-homogeneous-types-in-go.html
+	//	https://archive.is/NU4zR
+	if len(b) > 0 && b[0] == '[' {
+		return json.Unmarshal(b, (*[]Question)(ql))
+	}
+	var q Question
+	if err := json.Unmarshal(b, &q); err != nil {
+		return err
+	}
+	*ql = []Question{q}
+	return nil
+}
+
 type Response struct {
 	// Standard DNS response code (32 bit integer)
 	Status uint32 `json:"Status"`
@@ -41,7 +61,7 @@ type Response struct {
 	AD bool `json:"AD"`
 	// Whether the client asked to disable DNSSEC
 	CD               bool         `json:"CD"`
-	Question         []Question `json:"Question"`
+	Question         QuestionList `json:"Question"`
 	Answer           []RR         `json:"Answer,omitempty"`
 	Authority        []RR         `json:"Authority,omitempty"`
 	Additional       []RR         `json:"Additional,omitempty"`

json-dns/unmarshal.go

@@ -21,7 +21,7 @@
    DEALINGS IN THE SOFTWARE.
 */
 
-package jsonDNS
+package jsondns
 
 import (
 	"fmt"