Release 2.2.2

json-dns/response.go: Fix variant question response in Response.Question

.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

Changelog.md

@@ -4,6 +4,40 @@ This Changelog records major changes between versions.
 
 Not all changes are recorded. Please check git log for details.
 
+## 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
+
+## Version 2.2.0
+
+- Breaking change: The configuration format of doh-server is changed
+- Add support for type prefix for upstream addresses of doh-server
+- Add support for DNS-over-TLS upstream addresses of doh-server
+- Remove `tcp_only` configuration option in doh-server
+- Add `no_user_agent` configuration option in doh-server
+- Add an RPM package script with SELinux policy
+- Fix Opcode never assigned in `jsonDNS.PrepareReply`
+- Improve error logging / checking
+- Updated Readme
+
+## Version 2.1.2
+
+- Update address for google's resolver
+- Fix a typo
+
+## Version 2.1.1
+
+- Add a set of Dockerfile contributed by the community
+- Include DNS.SB's resolver in example configuration
+
 ## Version 2.1.0
 
 - Add `local_addr` configuration for doh-server (#39)

Dockerfile.client

@@ -0,0 +1,23 @@
+FROM golang:alpine AS build-env
+
+RUN apk add --no-cache git make
+
+WORKDIR /src
+ADD . /src
+RUN make doh-client/doh-client
+
+FROM alpine:latest
+
+COPY --from=build-env /src/doh-client/doh-client /doh-client
+
+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/udp
+EXPOSE 53/tcp
+EXPOSE 5380
+
+ENTRYPOINT ["/doh-client"]
+CMD ["-conf", "/doh-client.conf"]

Dockerfile.server

@@ -0,0 +1,20 @@
+FROM golang:alpine AS build-env
+
+RUN apk add --no-cache git make
+
+WORKDIR /src
+ADD . /src
+RUN make doh-server/doh-server
+
+FROM alpine:latest
+
+COPY --from=build-env /src/doh-server/doh-server /doh-server
+
+ADD doh-server/doh-server.conf /doh-server.conf
+
+RUN sed -i '$!N;s/"127.0.0.1:8053",\s*"\[::1\]:8053",/":8053",/;P;D' /doh-server.conf
+
+EXPOSE 8053
+
+ENTRYPOINT ["/doh-server"]
+CMD ["-conf", "/doh-server.conf"]

Makefile

@@ -59,6 +59,7 @@ uninstall:
 
 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/doh-client/config
 	$(GOGET_UPDATE) github.com/m13253/dns-over-https/json-dns
 	$(GOGET) ./doh-client ./doh-server
 

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 1.10.
+> 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.
-
-(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:
-
-    make
-
-To install DNS-over-HTTPS as Systemd services, type:
-
-    sudo make install
-
-By default, [Google DNS over HTTPS](https://dns.google.com) is used. It should
+- First create an empty directory, used for `$GOPATH`:
+```bash
+mkdir ~/gopath
+export GOPATH=~/gopath
+```
+- To build the program, type:
+```bash
+make
+```
+- 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
 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:
+```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.
 
-    sudoedit /etc/dns-over-https/doh-client.conf
+- To test your configuration, type:
+```bash
+dig www.google.com
+Output:
+;; SERVER: 127.0.0.1#53(127.0.0.1)
+```
+#### Uninstall
 
-To automatically start DNS-over-HTTPS client as a system service, type:
+- To uninstall, type:
+```bash
+sudo make uninstall
+```
+> Note: The configuration files are kept at `/etc/dns-over-https`. Remove them manually if you want.
 
-    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.
-
-To test your configuration, type:
-
-    dig www.google.com
-
-If it is OK, you will wee:
-
-    ;; SERVER: 127.0.0.1#53(127.0.0.1)
-
-### Uninstalling
-
-To uninstall, type:
-
-    sudo make uninstall
-
-The configuration files are kept at `/etc/dns-over-https`. Remove them manually if you want.
+### Using docker image
+```bash
+docker run -itd --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
 
@@ -79,12 +90,192 @@ 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.
 
+### 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
+SSLUseStapling on
+SSLStaplingCache shmcb:/var/lib/apache2/stapling_cache(512000)
+
+<VirtualHost *:443>
+    ServerName MY_SERVER_NAME
+    Protocols h2 http/1.1
+    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;
+  server_name  MY_SERVER_NAME;
+
+  server_tokens off;
+
+  ssl_protocols TLSv1.2 TLSv1.3;          # TLS 1.3 requires nginx >= 1.13.0
+  ssl_prefer_server_ciphers on;
+  ssl_dhparam /etc/nginx/dhparam.pem;     # openssl dhparam -dsaparam -out /etc/nginx/dhparam.pem 4096
+  ssl_ciphers EECDH+AESGCM:EDH+AESGCM;
+  ssl_ecdh_curve secp384r1;               # Requires nginx >= 1.1.0
+  ssl_session_timeout  10m;
+  ssl_session_cache shared:SSL:10m;
+  ssl_session_tickets off;                # Requires nginx >= 1.5.9
+  ssl_stapling on;                        # Requires nginx >= 1.3.7
+  ssl_stapling_verify on;                 # Requires nginx => 1.3.7
+  ssl_early_data off;                     # 0-RTT, enable if desired - Requires nginx >= 1.15.4
+  resolver 1.1.1.1 valid=300s;            # Replace with your local resolver
+  resolver_timeout 5s;
+  # HTTP Security Headers
+  add_header X-Frame-Options DENY;
+  add_header X-Content-Type-Options nosniff;
+  add_header X-XSS-Protection "1; mode=block";
+  add_header Strict-Transport-Security "max-age=63072000";
+  ssl_certificate /path/to/your/server/certificates/fullchain.pem;
+  ssl_certificate_key /path/to/your/server/certificates/privkey.pem;
+  location /dns-query {
+    proxy_pass       http://localhost:8053/dns-query;
+    proxy_set_header Host      $host;
+    proxy_set_header X-Real-IP $remote_addr;
+  }
+}
+```
+(Credit: [Cipherli.st](https://cipherli.st/))
+
+### Example configuration: Caddy (v2)
+```bash
+my.server.name {
+        reverse_proxy * localhost:8053
+        tls your@email.address
+        try_files {path} {path}/index.php /index.php?{query}
+}
+```
+### Example configuration: Docker Compose + Traefik + Unbound (Raspberry Pi/Linux/Mac) [linux/amd64,linux/arm64,linux/arm/v7]
+
+```yaml
+version: '2.2'
+networks:
+  default:
+services:
+  proxy:
+    # The official v2 Traefik docker image
+    image: traefik:v2.2
+    hostname: proxy
+    networks:
+      - default
+    environment:
+      TRAEFIK_ACCESSLOG: "true"
+      TRAEFIK_API: "true"
+      TRAEFIK_PROVIDERS_DOCKER: "true"
+      TRAEFIK_API_INSECURE: "true"
+      TRAEFIK_PROVIDERS_DOCKER_NETWORK: "${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
+
+> No IPV6 Support: Docker Swarm does not support IPV6 as of yet. Issue is logged [here](https://github.com/moby/moby/issues/24379)
+
+> IPV6 Support for Docker Compose based configuration TBA
+
 ## 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)
 

contrib/rpm/dns-over-https-2.1.2-systemd.patch

@@ -0,0 +1,36 @@
+diff -Naur dns-over-https-2.1.2.org/systemd/doh-client.service dns-over-https-2.1.2/systemd/doh-client.service
+--- dns-over-https-2.1.2.org/systemd/doh-client.service	2019-09-10 12:08:35.177574074 +0200
++++ dns-over-https-2.1.2/systemd/doh-client.service	2019-09-10 12:10:05.473700374 +0200
+@@ -7,12 +7,12 @@
+ 
+ [Service]
+ AmbientCapabilities=CAP_NET_BIND_SERVICE
+-ExecStart=/usr/local/bin/doh-client -conf /etc/dns-over-https/doh-client.conf
++ExecStart=/usr/bin/doh-client -conf /etc/dns-over-https/doh-client.conf
+ LimitNOFILE=1048576
+ Restart=always
+ RestartSec=3
+ Type=simple
+-User=nobody
++User=doh-client
+ 
+ [Install]
+ WantedBy=multi-user.target
+diff -Naur dns-over-https-2.1.2.org/systemd/doh-server.service dns-over-https-2.1.2/systemd/doh-server.service
+--- dns-over-https-2.1.2.org/systemd/doh-server.service	2019-09-10 12:08:35.177574074 +0200
++++ dns-over-https-2.1.2/systemd/doh-server.service	2019-09-10 12:10:20.980273992 +0200
+@@ -5,12 +5,12 @@
+ 
+ [Service]
+ AmbientCapabilities=CAP_NET_BIND_SERVICE
+-ExecStart=/usr/local/bin/doh-server -conf /etc/dns-over-https/doh-server.conf
++ExecStart=/usr/bin/doh-server -conf /etc/dns-over-https/doh-server.conf
+ LimitNOFILE=1048576
+ Restart=always
+ RestartSec=3
+ Type=simple
+-User=nobody
++User=doh-server
+ 
+ [Install]
+ WantedBy=multi-user.target

contrib/rpm/doh.spec

@@ -0,0 +1,240 @@
+# vim: tabstop=4 shiftwidth=4 expandtab
+%global _hardened_build 1
+# Debug package is empty anyway
+%define debug_package %{nil}
+
+%global _release        1
+%global provider        github
+%global provider_tld    com
+%global project         m13253
+%global repo            dns-over-https
+%global provider_prefix %{provider}.%{provider_tld}/%{project}/%{repo}
+%global import_path     %{provider_prefix}
+
+#define commit          984df34ca7b45897ecb5871791e398cc160a4b93
+
+%if 0%{?commit:1}
+%define shortcommit     %(c=%{commit}; echo ${c:0:7})
+%define _date           %(date +'%%Y%%m%%dT%%H%%M%%S')
+%endif
+
+%define rand_id         %(head -c20 /dev/urandom|od -An -tx1|tr -d '[[:space:]]')
+
+%if ! 0%{?gobuild:1}
+%define gobuild(o:) go build -ldflags "${LDFLAGS:-} -B 0x%{rand_id}" -a -v -x %{?**};
+%endif
+
+%if ! 0%{?gotest:1}
+%define gotest() go test -ldflags "${LDFLAGS:-}" %{?**}
+%endif
+
+Name:           %{repo}
+Version:        2.1.2
+%if 0%{?commit:1}
+Release:    %{_release}.git%{shortcommit}.%{_date}%{?dist}
+Source0:        https://%{import_path}/archive/%{commit}.tar.gz
+%else
+Release:        %{_release}%{?dist}
+Source0:        https://%{import_path}/archive/v%{version}.tar.gz
+%endif
+Patch0:         %{name}-%{version}-systemd.patch
+
+Summary:        High performance DNS over HTTPS client & server
+License:        MIT
+URL:            https://github.com/m13253/dns-over-https
+
+
+# e.g. el6 has ppc64 arch without gcc-go, so EA tag is required
+# If go_compiler is not set to 1, there is no virtual provide. Use golang instead.
+#BuildRequires:  %{?go_compiler:compiler(go-compiler)}%{!?go_compiler:golang} >= 1.10
+BuildRequires:  golang >= 1.10
+BuildRequires:  systemd
+BuildRequires:  upx
+
+%description
+%{summary}
+
+%package common
+BuildArch: noarch
+Summary: %{summary} - common files
+
+%description common
+%{summary}
+
+%package server
+ExclusiveArch:  %{?go_arches:%{go_arches}}%{!?go_arches:%{ix86} x86_64 %{arm}}
+Summary: %{summary} - Server
+Requires(pre):          shadow-utils
+Requires(post):         systemd
+Requires(preun):        systemd
+Requires(postun):       systemd
+
+%description server
+%{summary}
+
+%package client
+ExclusiveArch:  %{?go_arches:%{go_arches}}%{!?go_arches:%{ix86} x86_64 %{arm}}
+Summary: %{summary} - Client
+Requires(pre):          shadow-utils
+Requires(post):         systemd
+Requires(preun):        systemd
+Requires(postun):       systemd
+
+%description client
+%{summary}
+
+%package selinux
+BuildArch:      noarch
+
+Source3:        doh_server.fc
+Source4:        doh_server.if
+Source5:        doh_server.te
+Source6:        doh_client.fc
+Source7:        doh_client.if
+Source8:        doh_client.te
+
+BuildRequires:  selinux-policy
+BuildRequires:  selinux-policy-devel
+Requires:       %{name}
+
+Requires(post):     policycoreutils
+Requires(post):     policycoreutils-python 
+Requires(postun):   policycoreutils
+
+Summary: SELinux policy for %{name}
+
+%description selinux
+%summary
+ 
+%prep
+%if 0%{?commit:1}
+%autosetup -n %{name}-%{commit} -p1
+%else
+%autosetup -n %{name}-%{version} -p1
+%endif
+
+mkdir -p selinux
+cp %{SOURCE3} %{SOURCE4} %{SOURCE5} %{SOURCE6} %{SOURCE7} %{SOURCE8} selinux
+
+%build
+cd selinux
+make -f /usr/share/selinux/devel/Makefile doh_server.pp doh_client.pp || exit
+cd -
+
+%set_build_flags
+%make_build \
+    PREFIX=%{_prefix} \
+    GOBUILD="go build -ldflags \"-s -w -B 0x%{rand_id}\" -a -v -x"
+
+%install
+%make_install \
+    PREFIX=%{_prefix}
+install -Dpm 0600 selinux/doh_server.pp %{buildroot}%{_datadir}/selinux/packages/doh_server.pp
+install -Dpm 0644 selinux/doh_server.if %{buildroot}%{_datadir}/selinux/devel/include/contrib/doh_server.if
+install -Dpm 0600 selinux/doh_client.pp %{buildroot}%{_datadir}/selinux/packages/doh_client.pp
+install -Dpm 0644 selinux/doh_client.if %{buildroot}%{_datadir}/selinux/devel/include/contrib/doh_client.if
+
+mkdir -p %{buildroot}%{_docdir}/%{name}
+mv %{buildroot}%{_sysconfdir}/%{name}/*.example %{buildroot}%{_docdir}/%{name}
+
+mkdir -p %{buildroot}%{_libdir}
+mv %{buildroot}%{_sysconfdir}/NetworkManager %{buildroot}%{_libdir}/
+
+for i in $(find %{_buildroot}%{_bindir} -type f)
+do
+    upx $i
+done
+
+%files common
+%license LICENSE
+%doc Changelog.md Readme.md
+
+%files server
+%{_libdir}/NetworkManager/dispatcher.d/doh-server
+%{_docdir}/%{name}/doh-server.conf.example
+%config(noreplace) %{_sysconfdir}/%{name}/doh-server.conf
+%{_bindir}/doh-server
+%{_unitdir}/doh-server.service
+
+%files client
+%{_libdir}/NetworkManager/dispatcher.d/doh-client
+%{_docdir}/%{name}/doh-client.conf.example
+%config(noreplace) %{_sysconfdir}/%{name}/doh-client.conf
+%{_bindir}/doh-client
+%{_unitdir}/doh-client.service
+
+%pre server
+test -d %{_sharedstatedir}/home || mkdir -p %{_sharedstatedir}/home
+getent group doh-server > /dev/null || groupadd -r doh-server
+getent passwd doh-server > /dev/null || \
+    useradd -r -d %{_sharedstatedir}/home/doh-server -g doh-server \
+    -s /sbin/nologin -c "%{name} - server" doh-server
+exit 0
+
+%pre client
+test -d %{_sharedstatedir}/home || mkdir -p %{_sharedstatedir}/home
+getent group doh-client > /dev/null || groupadd -r doh-client
+getent passwd doh-client > /dev/null || \
+    useradd -r -d %{_sharedstatedir}/home/doh-client -g doh-client \
+    -s /sbin/nologin -c "%{name} - client" doh-client
+exit 0
+
+%post server
+%systemd_post doh-server.service
+
+%preun server
+%systemd_preun doh-server.service
+
+%postun server
+%systemd_postun_with_restart doh-server.service
+
+%post client
+%systemd_post doh-client.service
+
+%preun client
+%systemd_preun doh-client.service
+
+%postun client
+%systemd_postun_with_restart doh-client.service
+
+%files selinux
+%{_datadir}/selinux/packages/doh_server.pp
+%{_datadir}/selinux/devel/include/contrib/doh_server.if
+%{_datadir}/selinux/packages/doh_client.pp
+%{_datadir}/selinux/devel/include/contrib/doh_client.if
+
+%post selinux
+semodule -n -i %{_datadir}/selinux/packages/doh_server.pp
+semodule -n -i %{_datadir}/selinux/packages/doh_client.pp
+if /usr/sbin/selinuxenabled ; then
+    /usr/sbin/load_policy
+    /usr/sbin/fixfiles -R %{name}-server restore
+    /usr/sbin/fixfiles -R %{name}-client restore
+fi;
+semanage -i - << __eof
+port -a -t doh_server_port_t -p tcp "8053"
+port -a -t doh_client_port_t -p udp "5380"
+__eof
+exit 0
+
+%postun selinux
+if [ $1 -eq 0 ]; then
+    semanage -i - << __eof
+port -d -t doh_server_port_t -p tcp "8053"
+port -d -t doh_client_port_t -p udp "5380"
+__eof
+
+    semodule -n -r doh_server
+    semodule -n -r doh_client
+    if /usr/sbin/selinuxenabled ; then
+       /usr/sbin/load_policy
+       /usr/sbin/fixfiles -R %{name}-server restore
+       /usr/sbin/fixfiles -R %{name}-client restore
+    fi;
+fi;
+exit 0
+
+%changelog
+* Tue Sep 10 2019 fuero <fuerob@gmail.com> 2.1.2-1
+- initial package
+

contrib/rpm/doh_client.fc

@@ -0,0 +1,2 @@
+/usr/bin/doh-client					--	gen_context(system_u:object_r:doh_client_exec_t,s0)
+/usr/lib/systemd/system/doh-client.service		--	gen_context(system_u:object_r:doh_client_unit_file_t,s0)

contrib/rpm/doh_client.if

@@ -0,0 +1,103 @@
+
+## <summary>policy for doh_client</summary>
+
+########################################
+## <summary>
+##	Execute doh_client_exec_t in the doh_client domain.
+## </summary>
+## <param name="domain">
+## <summary>
+##	Domain allowed to transition.
+## </summary>
+## </param>
+#
+interface(`doh_client_domtrans',`
+	gen_require(`
+		type doh_client_t, doh_client_exec_t;
+	')
+
+	corecmd_search_bin($1)
+	domtrans_pattern($1, doh_client_exec_t, doh_client_t)
+')
+
+######################################
+## <summary>
+##	Execute doh_client in the caller domain.
+## </summary>
+## <param name="domain">
+##	<summary>
+##	Domain allowed access.
+##	</summary>
+## </param>
+#
+interface(`doh_client_exec',`
+	gen_require(`
+		type doh_client_exec_t;
+	')
+
+	corecmd_search_bin($1)
+	can_exec($1, doh_client_exec_t)
+')
+########################################
+## <summary>
+##	Execute doh_client server in the doh_client domain.
+## </summary>
+## <param name="domain">
+##	<summary>
+##	Domain allowed to transition.
+##	</summary>
+## </param>
+#
+interface(`doh_client_systemctl',`
+	gen_require(`
+		type doh_client_t;
+		type doh_client_unit_file_t;
+	')
+
+	systemd_exec_systemctl($1)
+        systemd_read_fifo_file_passwd_run($1)
+	allow $1 doh_client_unit_file_t:file read_file_perms;
+	allow $1 doh_client_unit_file_t:service manage_service_perms;
+
+	ps_process_pattern($1, doh_client_t)
+')
+
+
+########################################
+## <summary>
+##	All of the rules required to administrate
+##	an doh_client environment
+## </summary>
+## <param name="domain">
+##	<summary>
+##	Domain allowed access.
+##	</summary>
+## </param>
+## <param name="role">
+##	<summary>
+##	Role allowed access.
+##	</summary>
+## </param>
+## <rolecap/>
+#
+interface(`doh_client_admin',`
+	gen_require(`
+		type doh_client_t;
+	type doh_client_unit_file_t;
+	')
+
+	allow $1 doh_client_t:process { signal_perms };
+	ps_process_pattern($1, doh_client_t)
+
+    tunable_policy(`deny_ptrace',`',`
+        allow $1 doh_client_t:process ptrace;
+    ')
+
+	doh_client_systemctl($1)
+	admin_pattern($1, doh_client_unit_file_t)
+	allow $1 doh_client_unit_file_t:service all_service_perms;
+	optional_policy(`
+		systemd_passwd_agent_exec($1)
+		systemd_read_fifo_file_passwd_run($1)
+	')
+')

contrib/rpm/doh_client.te

@@ -0,0 +1,49 @@
+policy_module(doh_client, 1.0.0)
+
+########################################
+#
+# Declarations
+#
+
+type doh_client_t;
+type doh_client_exec_t;
+init_daemon_domain(doh_client_t, doh_client_exec_t)
+
+type doh_client_port_t;
+
+corenet_port(doh_client_port_t)
+
+type doh_client_unit_file_t;
+systemd_unit_file(doh_client_unit_file_t)
+
+########################################
+#
+# doh_client local policy
+#
+allow doh_client_t self:fifo_file rw_fifo_file_perms;
+allow doh_client_t self:unix_stream_socket create_stream_socket_perms;
+
+allow doh_client_t self:capability net_bind_service;
+allow doh_client_t self:process execmem;
+allow doh_client_t self:tcp_socket { accept bind connect create getattr getopt listen read setopt write };
+allow doh_client_t self:udp_socket { bind connect create getattr read setopt write };
+
+allow doh_client_t doh_client_exec_t:file execmod;
+allow doh_client_t doh_client_port_t:tcp_socket name_bind;
+
+corenet_tcp_bind_dns_port(doh_client_t)
+corenet_tcp_bind_generic_node(doh_client_t)
+corenet_tcp_connect_http_port(doh_client_t)
+corenet_udp_bind_dns_port(doh_client_t)
+corenet_udp_bind_generic_node(doh_client_t)
+corenet_udp_bind_generic_port(doh_client_t)
+kernel_read_net_sysctls(doh_client_t)
+kernel_search_network_sysctl(doh_client_t)
+miscfiles_read_certs(doh_client_t)
+sysnet_read_config(doh_client_t)
+
+domain_use_interactive_fds(doh_client_t)
+
+files_read_etc_files(doh_client_t)
+
+miscfiles_read_localization(doh_client_t)

contrib/rpm/doh_server.fc

@@ -0,0 +1,2 @@
+/usr/bin/doh-server					--	gen_context(system_u:object_r:doh_server_exec_t,s0)
+/usr/lib/systemd/system/doh-server.service		--	gen_context(system_u:object_r:doh_server_unit_file_t,s0)

contrib/rpm/doh_server.if

@@ -0,0 +1,122 @@
+
+## <summary>policy for doh_server</summary>
+
+########################################
+## <summary>
+##	Execute doh_server_exec_t in the doh_server domain.
+## </summary>
+## <param name="domain">
+## <summary>
+##	Domain allowed to transition.
+## </summary>
+## </param>
+#
+interface(`doh_server_domtrans',`
+	gen_require(`
+		type doh_server_t, doh_server_exec_t;
+	')
+
+	corecmd_search_bin($1)
+	domtrans_pattern($1, doh_server_exec_t, doh_server_t)
+')
+
+######################################
+## <summary>
+##	Execute doh_server in the caller domain.
+## </summary>
+## <param name="domain">
+##	<summary>
+##	Domain allowed access.
+##	</summary>
+## </param>
+#
+interface(`doh_server_exec',`
+	gen_require(`
+		type doh_server_exec_t;
+	')
+
+	corecmd_search_bin($1)
+	can_exec($1, doh_server_exec_t)
+')
+########################################
+## <summary>
+##	Execute doh_server server in the doh_server domain.
+## </summary>
+## <param name="domain">
+##	<summary>
+##	Domain allowed to transition.
+##	</summary>
+## </param>
+#
+interface(`doh_server_systemctl',`
+	gen_require(`
+		type doh_server_t;
+		type doh_server_unit_file_t;
+	')
+
+	systemd_exec_systemctl($1)
+        systemd_read_fifo_file_passwd_run($1)
+	allow $1 doh_server_unit_file_t:file read_file_perms;
+	allow $1 doh_server_unit_file_t:service manage_service_perms;
+
+	ps_process_pattern($1, doh_server_t)
+')
+
+
+########################################
+## <summary>
+##	All of the rules required to administrate
+##	an doh_server environment
+## </summary>
+## <param name="domain">
+##	<summary>
+##	Domain allowed access.
+##	</summary>
+## </param>
+## <param name="role">
+##	<summary>
+##	Role allowed access.
+##	</summary>
+## </param>
+## <rolecap/>
+#
+interface(`doh_server_admin',`
+	gen_require(`
+		type doh_server_t;
+	type doh_server_unit_file_t;
+	')
+
+	allow $1 doh_server_t:process { signal_perms };
+	ps_process_pattern($1, doh_server_t)
+
+    tunable_policy(`deny_ptrace',`',`
+        allow $1 doh_server_t:process ptrace;
+    ')
+
+	doh_server_systemctl($1)
+	admin_pattern($1, doh_server_unit_file_t)
+	allow $1 doh_server_unit_file_t:service all_service_perms;
+	optional_policy(`
+		systemd_passwd_agent_exec($1)
+		systemd_read_fifo_file_passwd_run($1)
+	')
+')
+
+########################################
+## <summary>
+##      Make a TCP connection to the vault_ocsp_responder port.
+## </summary>
+## <param name="domain">
+##      <summary>
+##      Domain allowed access.
+##      </summary>
+## </param>
+#
+interface(`doh_server_connect',`
+        gen_require(`
+                type doh_server_port_t;
+		type $1;
+        ')
+
+        allow $1 doh_server_port_t:tcp_socket name_connect;
+')

contrib/rpm/doh_server.te

@@ -0,0 +1,42 @@
+policy_module(doh_server, 1.0.0)
+
+require {
+	class process execmem;
+	class tcp_socket { accept bind create read write getattr listen setopt connect getopt };
+	class udp_socket { connect create getattr setopt read write };
+	class file execmod;
+}
+
+type doh_server_t;
+type doh_server_exec_t;
+
+init_daemon_domain(doh_server_t, doh_server_exec_t)
+
+type doh_server_port_t;
+
+corenet_port(doh_server_port_t)
+
+type doh_server_unit_file_t;
+systemd_unit_file(doh_server_unit_file_t)
+
+allow doh_server_t self:fifo_file rw_fifo_file_perms;
+allow doh_server_t self:unix_stream_socket create_stream_socket_perms;
+allow doh_server_t self:process execmem;
+allow doh_server_t self:tcp_socket { accept read write bind create getattr listen setopt connect getopt};
+allow doh_server_t self:udp_socket { connect create getattr setopt read write };
+
+allow doh_server_t doh_server_exec_t:file execmod;
+allow doh_server_t doh_server_port_t:tcp_socket name_bind;
+
+domain_use_interactive_fds(doh_server_t)
+
+files_read_etc_files(doh_server_t)
+
+corenet_tcp_bind_generic_node(doh_server_t)
+corenet_tcp_connect_dns_port(doh_server_t)
+doh_server_connect(httpd_t)
+
+kernel_read_net_sysctls(doh_server_t)
+kernel_search_network_sysctl(doh_server_t)
+
+miscfiles_read_localization(doh_server_t)

doh-client/client.go

@@ -39,7 +39,7 @@ import (
 
 	"github.com/m13253/dns-over-https/doh-client/config"
 	"github.com/m13253/dns-over-https/doh-client/selector"
-	"github.com/m13253/dns-over-https/json-dns"
+	jsonDNS "github.com/m13253/dns-over-https/json-dns"
 	"github.com/miekg/dns"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/idna"

doh-client/config/config.go

@@ -53,6 +53,7 @@ type others struct {
 	NoCookies        bool     `toml:"no_cookies"`
 	NoECS            bool     `toml:"no_ecs"`
 	NoIPv6           bool     `toml:"no_ipv6"`
+	NoUserAgent      bool     `toml:"no_user_agent"`
 	Verbose          bool     `toml:"verbose"`
 	DebugHTTPHeaders []string `toml:"debug_http_headers"`
 }

doh-client/doh-client.conf

@@ -4,6 +4,9 @@ listen = [
     "127.0.0.1:5380",
     "[::1]:53",
     "[::1]:5380",
+
+    ## To listen on both 0.0.0.0:53 and [::]:53, use the following line
+    # ":53",
 ]
 
 # HTTP path for upstream resolver
@@ -15,9 +18,9 @@ upstream_selector = "random"
 
 # weight should in (0, 100], if upstream_selector is random, weight will be ignored
 
-## Google's productive resolver, good ECS, bad DNSSEC
-#[[upstream.upstream_google]]
-#    url = "https://dns.google.com/resolve"
+## Google's resolver, good ECS, good DNSSEC
+#[[upstream.upstream_ietf]]
+#    url = "https://dns.google/dns-query"
 #    weight = 50
 
 ## CloudFlare's resolver, bad ECS, good DNSSEC
@@ -33,17 +36,18 @@ upstream_selector = "random"
 #    url = "https://1.1.1.1/dns-query"
 #    weight = 50
 
+## DNS.SB's resolver, good ECS, good DNSSEC
+## The provider claims no logging: https://dns.sb/doh/
+#[[upstream.upstream_ietf]]
+#    url = "https://doh.dns.sb/dns-query"
+#    weight = 50
+
 ## Quad9's resolver, bad ECS, good DNSSEC
 ## ECS is disabled for privacy by design: https://www.quad9.net/faq/#What_is_EDNS_Client-Subnet
 #[[upstream.upstream_ietf]]
 #    url = "https://9.9.9.9/dns-query"
 #    weight = 50
 
-## Google's experimental resolver, good ECS, good DNSSEC
-#[[upstream.upstream_ietf]]
-#    url = "https://dns.google.com/experimental"
-#    weight = 50
-
 ## CloudFlare's resolver for Tor, available only with Tor
 ## Remember to disable ECS below when using Tor!
 ## Blog: https://blog.cloudflare.com/welcome-hidden-resolver/
@@ -115,5 +119,16 @@ no_ecs = false
 # Note that DNS listening and bootstrapping is not controlled by this option.
 no_ipv6 = false
 
+# Disable submitting User-Agent
+#
+# It is generally not recommended to disable submitting User-Agent because it
+# is still possible to probe client version according to behavior differences,
+# such as TLS handshaking, handling of malformed packets, and specific bugs.
+# Additionally, User-Agent is an important way for the server to distinguish
+# buggy, old, or insecure clients, and to workaround specific bugs.
+# (e.g. doh-server can detect and workaround certain issues of DNSCrypt-Proxy
+# and older Firefox.)
+no_user_agent = false
+
 # Enable logging
 verbose = false

doh-client/google.go

@@ -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)
@@ -86,7 +89,11 @@ func (c *Client) generateRequestGoogle(ctx context.Context, w dns.ResponseWriter
 	}
 
 	req.Header.Set("Accept", "application/json, application/dns-message, application/dns-udpwireformat")
-	req.Header.Set("User-Agent", USER_AGENT)
+	if !c.conf.Other.NoUserAgent {
+		req.Header.Set("User-Agent", USER_AGENT)
+	} else {
+		req.Header.Set("User-Agent", "")
+	}
 	req = req.WithContext(ctx)
 
 	c.httpClientMux.RLock()
@@ -153,6 +160,7 @@ 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)
 	buf, err := fullReply.Pack()
@@ -173,3 +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

@@ -36,7 +36,7 @@ import (
 	"time"
 
 	"github.com/m13253/dns-over-https/doh-client/selector"
-	"github.com/m13253/dns-over-https/json-dns"
+	jsonDNS "github.com/m13253/dns-over-https/json-dns"
 	"github.com/miekg/dns"
 )
 
@@ -128,7 +128,11 @@ func (c *Client) generateRequestIETF(ctx context.Context, w dns.ResponseWriter,
 		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", USER_AGENT)
+	if !c.conf.Other.NoUserAgent {
+		req.Header.Set("User-Agent", USER_AGENT)
+	} else {
+		req.Header.Set("User-Agent", "")
+	}
 	req = req.WithContext(ctx)
 	c.httpClientMux.RLock()
 	resp, err := c.httpClient.Do(req)
@@ -176,7 +180,7 @@ func (c *Client) parseResponseIETF(ctx context.Context, w dns.ResponseWriter, r
 
 	body, err := ioutil.ReadAll(req.response.Body)
 	if err != nil {
-		log.Println(err)
+		log.Printf("read error from upstream %s: %v\n", req.currentUpstream, err)
 		req.reply.Rcode = dns.RcodeServerFailure
 		w.WriteMsg(req.reply)
 		return
@@ -187,7 +191,7 @@ func (c *Client) parseResponseIETF(ctx context.Context, w dns.ResponseWriter, r
 		if nowDate, err := time.Parse(http.TimeFormat, headerNow); err == nil {
 			now = nowDate
 		} else {
-			log.Println(err)
+			log.Printf("Date header parse error from upstream %s: %v\n", req.currentUpstream, err)
 		}
 	}
 	headerLastModified := req.response.Header.Get("Last-Modified")
@@ -196,7 +200,7 @@ func (c *Client) parseResponseIETF(ctx context.Context, w dns.ResponseWriter, r
 		if lastModifiedDate, err := time.Parse(http.TimeFormat, headerLastModified); err == nil {
 			lastModified = lastModifiedDate
 		} else {
-			log.Println(err)
+			log.Printf("Last-Modified header parse error from upstream %s: %v\n", req.currentUpstream, err)
 		}
 	}
 	timeDelta := now.Sub(lastModified)
@@ -207,7 +211,7 @@ func (c *Client) parseResponseIETF(ctx context.Context, w dns.ResponseWriter, r
 	fullReply := new(dns.Msg)
 	err = fullReply.Unpack(body)
 	if err != nil {
-		log.Println(err)
+		log.Printf("unpacking error from upstream %s: %v\n", req.currentUpstream, err)
 		req.reply.Rcode = dns.RcodeServerFailure
 		w.WriteMsg(req.reply)
 		return
@@ -229,7 +233,7 @@ func (c *Client) parseResponseIETF(ctx context.Context, w dns.ResponseWriter, r
 
 	buf, err := fullReply.Pack()
 	if err != nil {
-		log.Println(err)
+		log.Printf("packing error with upstream %s: %v\n", req.currentUpstream, err)
 		req.reply.Rcode = dns.RcodeServerFailure
 		w.WriteMsg(req.reply)
 		return
@@ -238,12 +242,15 @@ func (c *Client) parseResponseIETF(ctx context.Context, w dns.ResponseWriter, r
 		fullReply.Truncated = true
 		buf, err = fullReply.Pack()
 		if err != nil {
-			log.Println(err)
+			log.Printf("re-packing error with upstream %s: %v\n", req.currentUpstream, err)
 			return
 		}
 		buf = buf[:req.udpSize]
 	}
-	w.Write(buf)
+	_, err = w.Write(buf)
+	if err != nil {
+		log.Printf("failed to write to client: %v\n", err)
+	}
 }
 
 func fixRecordTTL(rr dns.RR, delta time.Duration) dns.RR {

doh-client/main.go

@@ -89,7 +89,7 @@ func main() {
 	flag.Parse()
 
 	if *showVersion {
-		fmt.Printf("doh-server %s\nHomepage: https://github.com/m13253/dns-over-https\n", VERSION)
+		fmt.Printf("doh-client %s\nHomepage: https://github.com/m13253/dns-over-https\n", VERSION)
 		return
 	}
 

doh-client/version.go

@@ -24,6 +24,6 @@
 package main
 
 const (
-	VERSION    = "2.1.0"
+	VERSION    = "2.2.2"
 	USER_AGENT = "DNS-over-HTTPS/" + VERSION + " (+https://github.com/m13253/dns-over-https)"
 )

doh-server/config.go

@@ -25,6 +25,7 @@ package main
 
 import (
 	"fmt"
+	"regexp"
 
 	"github.com/BurntSushi/toml"
 )
@@ -38,7 +39,6 @@ type config struct {
 	Upstream         []string `toml:"upstream"`
 	Timeout          uint     `toml:"timeout"`
 	Tries            uint     `toml:"tries"`
-	TCPOnly          bool     `toml:"tcp_only"`
 	Verbose          bool     `toml:"verbose"`
 	DebugHTTPHeaders []string `toml:"debug_http_headers"`
 	LogGuessedIP     bool     `toml:"log_guessed_client_ip"`
@@ -62,7 +62,7 @@ func loadConfig(path string) (*config, error) {
 		conf.Path = "/dns-query"
 	}
 	if len(conf.Upstream) == 0 {
-		conf.Upstream = []string{"8.8.8.8:53", "8.8.4.4:53"}
+		conf.Upstream = []string{"udp:8.8.8.8:53", "udp:8.8.4.4:53"}
 	}
 	if conf.Timeout == 0 {
 		conf.Timeout = 10
@@ -75,9 +75,35 @@ func loadConfig(path string) (*config, error) {
 		return nil, &configError{"You must specify both -cert and -key to enable TLS"}
 	}
 
+	// validate all upstreams
+	for _, us := range conf.Upstream {
+		address, t := addressAndType(us)
+		if address == "" {
+			return nil, &configError{"One of the upstreams has not a (udp|tcp|tcp-tls) prefix e.g. udp:1.1.1.1:53"}
+		}
+
+		switch t {
+		case "tcp", "udp", "tcp-tls":
+			// OK
+		default:
+			return nil, &configError{"Invalid upstream prefix specified, choose one of: udp tcp tcp-tls"}
+		}
+	}
+
 	return conf, nil
 }
 
+var rxUpstreamWithTypePrefix = regexp.MustCompile("^[a-z-]+(:)")
+
+func addressAndType(us string) (string, string) {
+	p := rxUpstreamWithTypePrefix.FindStringSubmatchIndex(us)
+	if len(p) != 4 {
+		return "", ""
+	}
+
+	return us[p[2]+1:], us[:p[2]]
+}
+
 type configError struct {
 	err string
 }

doh-server/doh-server.conf

@@ -2,6 +2,9 @@
 listen = [
     "127.0.0.1:8053",
     "[::1]:8053",
+
+    ## To listen on both 0.0.0.0:8053 and [::]:8053, use the following line
+    # ":8053",
 ]
 
 # Local address and port for upstream DNS
@@ -24,11 +27,16 @@ path = "/dns-query"
 
 # Upstream DNS resolver
 # If multiple servers are specified, a random one will be chosen each time.
+# You can use "udp", "tcp" or "tcp-tls" for the type prefix.
+# For "udp", UDP will first be used, and switch to TCP when the server asks to
+# or the response is too large.
+# For "tcp", only TCP will be used.
+# For "tcp-tls", DNS-over-TLS (RFC 7858) will be used to secure the upstream connection.
 upstream = [
-    "1.1.1.1:53",
-    "1.0.0.1:53",
-    "8.8.8.8:53",
-    "8.8.4.4:53",
+    "udp:1.1.1.1:53",
+    "udp:1.0.0.1:53",
+    "udp:8.8.8.8:53",
+    "udp:8.8.4.4:53",
 ]
 
 # Upstream timeout
@@ -37,9 +45,6 @@ timeout = 10
 # Number of tries if upstream DNS fails
 tries = 3
 
-# Only use TCP for DNS query
-tcp_only = false
-
 # Enable logging
 verbose = false
 

doh-server/ietf.go

@@ -36,7 +36,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/m13253/dns-over-https/json-dns"
+	jsonDNS "github.com/m13253/dns-over-https/json-dns"
 	"github.com/miekg/dns"
 )
 
@@ -160,7 +160,7 @@ func (s *Server) generateResponseIETF(ctx context.Context, w http.ResponseWriter
 	req.response.Id = req.transactionID
 	respBytes, err := req.response.Pack()
 	if err != nil {
-		log.Println(err)
+		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)
 		return
 	}
@@ -183,9 +183,13 @@ func (s *Server) generateResponseIETF(ctx context.Context, w http.ResponseWriter
 	}
 
 	if respJSON.Status == dns.RcodeServerFailure {
+		log.Printf("received server failure from upstream %s: %v\n", req.currentUpstream, req.response)
 		w.WriteHeader(503)
 	}
-	w.Write(respBytes)
+	_, err = w.Write(respBytes)
+	if err != nil {
+		log.Printf("failed to write to client: %v\n", err)
+	}
 }
 
 // Workaround a bug causing DNSCrypt-Proxy to expect a response with TransactionID = 0xcafe

doh-server/server.go

@@ -35,15 +35,16 @@ import (
 	"time"
 
 	"github.com/gorilla/handlers"
-	"github.com/m13253/dns-over-https/json-dns"
+	jsonDNS "github.com/m13253/dns-over-https/json-dns"
 	"github.com/miekg/dns"
 )
 
 type Server struct {
-	conf      *config
-	udpClient *dns.Client
-	tcpClient *dns.Client
-	servemux  *http.ServeMux
+	conf         *config
+	udpClient    *dns.Client
+	tcpClient    *dns.Client
+	tcpClientTLS *dns.Client
+	servemux     *http.ServeMux
 }
 
 type DNSRequest struct {
@@ -69,6 +70,10 @@ func NewServer(conf *config) (*Server, error) {
 			Net:     "tcp",
 			Timeout: timeout,
 		},
+		tcpClientTLS: &dns.Client{
+			Net:     "tcp-tls",
+			Timeout: timeout,
+		},
 		servemux: http.NewServeMux(),
 	}
 	if conf.LocalAddr != "" {
@@ -88,6 +93,10 @@ func NewServer(conf *config) (*Server, error) {
 			Timeout:   timeout,
 			LocalAddr: tcpLocalAddr,
 		}
+		s.tcpClientTLS.Dialer = &net.Dialer{
+			Timeout:   timeout,
+			LocalAddr: tcpLocalAddr,
+		}
 	}
 	s.servemux.HandleFunc(conf.Path, s.handlerFunc)
 	return s, nil
@@ -127,6 +136,18 @@ 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", "*")
@@ -225,6 +246,11 @@ 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, ",") {
@@ -274,28 +300,39 @@ func (s *Server) indexQuestionType(msg *dns.Msg, qtype uint16) int {
 }
 
 func (s *Server) doDNSQuery(ctx context.Context, req *DNSRequest) (resp *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)]
 
-		// Use TCP if always configured to or if the Query type dictates it (AXFR)
-		if s.conf.TCPOnly || (s.indexQuestionType(req.request, dns.TypeAXFR) > -1) {
-			req.response, _, err = s.tcpClient.Exchange(req.request, req.currentUpstream)
-		} else {
-			req.response, _, err = s.udpClient.Exchange(req.request, req.currentUpstream)
-			if err == nil && req.response != nil && req.response.Truncated {
-				log.Println(err)
-				req.response, _, err = s.tcpClient.Exchange(req.request, req.currentUpstream)
-			}
+		upstream, t := addressAndType(req.currentUpstream)
 
-			// 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, req.currentUpstream)
+		switch t {
+		default:
+			log.Printf("invalid DNS type %q in upstream %q", t, upstream)
+			return nil, &configError{"invalid DNS type"}
+		// Use DNS-over-TLS (DoT) if configured to do so
+		case "tcp-tls":
+			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.ExchangeContext(ctx, req.request, upstream)
+			} else {
+				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.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.ExchangeContext(ctx, req.request, upstream)
+				}
 			}
 		}
+
 		if err == nil {
 			return req, nil
 		}

doh-server/version.go

@@ -24,6 +24,6 @@
 package main
 
 const (
-	VERSION    = "2.1.0"
+	VERSION    = "2.2.2"
 	USER_AGENT = "DNS-over-HTTPS/" + VERSION + " (+https://github.com/m13253/dns-over-https)"
 )

go.mod

@@ -5,9 +5,9 @@ go 1.12
 require (
 	github.com/BurntSushi/toml v0.3.1
 	github.com/gorilla/handlers v1.4.0
-	github.com/miekg/dns v1.1.6
-	golang.org/x/crypto v0.0.0-20190313024323-a1f597ede03a // indirect
-	golang.org/x/net v0.0.0-20190311183353-d8887717615a
-	golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6 // indirect
-	golang.org/x/sys v0.0.0-20190312061237-fead79001313 // indirect
+	github.com/miekg/dns v1.1.31
+	golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de // indirect
+	golang.org/x/net v0.0.0-20200707034311-ab3426394381
+	golang.org/x/sys v0.0.0-20200728102440-3e129f6d46b1 // indirect
+	golang.org/x/text v0.3.2 // indirect
 )

go.sum

@@ -2,24 +2,54 @@ github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/gorilla/handlers v1.4.0 h1:XulKRWSQK5uChr4pEgSE4Tc/OcmnU9GJuSwdog/tZsA=
 github.com/gorilla/handlers v1.4.0/go.mod h1:Qkdc/uu4tH4g6mTK6auzZ766c4CA0Ng8+o/OAirnOIQ=
-github.com/miekg/dns v1.1.4 h1:rCMZsU2ScVSYcAsOXgmC6+AKOK+6pmQTOcw03nfwYV0=
-github.com/miekg/dns v1.1.4/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
-github.com/miekg/dns v1.1.6 h1:jVwb4GDwD65q/gtItR/lIZHjNH93QfeGxZUkzJcW9mc=
-github.com/miekg/dns v1.1.6/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90PveolxSbWFaJdECFbxSq0Mqo2M=
+github.com/miekg/dns v1.1.14 h1:wkQWn9wIp4mZbwW8XV6Km6owkvRPbOiV004ZM2CkGvA=
+github.com/miekg/dns v1.1.14/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
+github.com/miekg/dns v1.1.22 h1:Jm64b3bO9kP43ddLjL2EY3Io6bmy1qGb9Xxz6TqS6rc=
+github.com/miekg/dns v1.1.22/go.mod h1:bPDLeHnStXmXAq1m/Ch/hvfNHr14JKNPMBo3VZKjuso=
+github.com/miekg/dns v1.1.30 h1:Qww6FseFn8PRfw07jueqIXqodm0JKiiKuK0DeXSqfyo=
+github.com/miekg/dns v1.1.30/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
+github.com/miekg/dns v1.1.31 h1:sJFOl9BgwbYAWOGEwr61FU28pqsBNdpRBnhGXtO06Oo=
+github.com/miekg/dns v1.1.31/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20190313024323-a1f597ede03a h1:YX8ljsm6wXlHZO+aRz9Exqr0evNhKRNe5K/gi+zKh4U=
-golang.org/x/crypto v0.0.0-20190313024323-a1f597ede03a/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/net v0.0.0-20190301231341-16b79f2e4e95 h1:fY7Dsw114eJN4boqzVSbpVHO6rTdhq6/GnXeu+PKnzU=
-golang.org/x/net v0.0.0-20190301231341-16b79f2e4e95/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
-golang.org/x/net v0.0.0-20190311183353-d8887717615a h1:oWX7TPOiFAMXLq8o0ikBYfCJVlRHBcsciT5bXOrH628=
-golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6 h1:bjcUS9ztw9kFmmIxJInhon/0Is3p+EHBKNgquIzo1OI=
-golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/crypto v0.0.0-20190621222207-cc06ce4a13d4 h1:ydJNl0ENAG67pFbB+9tfhiL2pYqLhfoaZFw/cjLhY4A=
+golang.org/x/crypto v0.0.0-20190621222207-cc06ce4a13d4/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
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+golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 h1:ObdrDkeb4kJdCP557AjRjq69pTHfNouLtWZG7j9rPN8=
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 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190308023053-584f3b12f43e h1:K7CV15oJ823+HLXQ+M7MSMrUg8LjfqY7O3naO+8Pp/I=
-golang.org/x/sys v0.0.0-20190308023053-584f3b12f43e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190312061237-fead79001313 h1:pczuHS43Cp2ktBEEmLwScxgjWsBSzdaQiKzUyf3DTTc=
-golang.org/x/sys v0.0.0-20190312061237-fead79001313/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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json-dns/response.go

@@ -24,9 +24,29 @@
 package jsonDNS
 
 import (
+	"encoding/json"
 	"time"
 )
 
+type QuestionList []Question
+
+// 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
+func (ql *QuestionList) UnmarshalJSON(b []byte) error {
+	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"`
@@ -40,13 +60,13 @@ type Response struct {
 	// FIXME: We don't have DNSSEC yet! This bit is not reliable!
 	AD bool `json:"AD"`
 	// Whether the client asked to disable DNSSEC
-	CD               bool       `json:"CD"`
-	Question         []Question `json:"Question"`
-	Answer           []RR       `json:"Answer,omitempty"`
-	Authority        []RR       `json:"Authority,omitempty"`
-	Additional       []RR       `json:"Additional,omitempty"`
-	Comment          string     `json:"Comment,omitempty"`
-	EdnsClientSubnet string     `json:"edns_client_subnet,omitempty"`
+	CD               bool           `json:"CD"`
+	Question         QuestionList   `json:"Question"`
+	Answer           []RR           `json:"Answer,omitempty"`
+	Authority        []RR           `json:"Authority,omitempty"`
+	Additional       []RR           `json:"Additional,omitempty"`
+	Comment          string         `json:"Comment,omitempty"`
+	EdnsClientSubnet string         `json:"edns_client_subnet,omitempty"`
 	// Least time-to-live
 	HaveTTL         bool      `json:"-"`
 	LeastTTL        uint32    `json:"-"`

json-dns/unmarshal.go

@@ -38,7 +38,7 @@ func PrepareReply(req *dns.Msg) *dns.Msg {
 	reply := new(dns.Msg)
 	reply.Id = req.Id
 	reply.Response = true
-	reply.Opcode = reply.Opcode
+	reply.Opcode = req.Opcode
 	reply.RecursionDesired = req.RecursionDesired
 	reply.RecursionAvailable = req.RecursionDesired
 	reply.CheckingDisabled = req.CheckingDisabled