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Implement IETF protocol

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Star Brilliant
2018-03-21 00:14:59 +08:00
parent f4e27c93a6
commit 521b4b6abc
17 changed files with 912 additions and 582 deletions
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65
doh-server/config.go
View File

@@ -1,63 +1,64 @@
/*
DNS-over-HTTPS
Copyright (C) 2017 Star Brilliant <m13253@hotmail.com>
DNS-over-HTTPS
Copyright (C) 2017-2018 Star Brilliant <m13253@hotmail.com>
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/
package main
import (
"fmt"
"github.com/BurntSushi/toml"
)
type config struct {
Listen string `toml:"listen"`
Cert string `toml:"cert"`
Key string `toml:"key"`
Path string `toml:"path"`
Upstream []string `toml:"upstream"`
Timeout uint `toml:"timeout"`
Tries uint `toml:"tries"`
TCPOnly bool `toml:"tcp_only"`
Verbose bool `toml:"verbose"`
Listen string `toml:"listen"`
Cert string `toml:"cert"`
Key string `toml:"key"`
Path string `toml:"path"`
Upstream []string `toml:"upstream"`
Timeout uint `toml:"timeout"`
Tries uint `toml:"tries"`
TCPOnly bool `toml:"tcp_only"`
Verbose bool `toml:"verbose"`
}
func loadConfig(path string) (*config, error) {
conf := &config {}
conf := &config{}
metaData, err := toml.DecodeFile(path, conf)
if err != nil {
return nil, err
}
for _, key := range metaData.Undecoded() {
return nil, &configError { fmt.Sprintf("unknown option %q", key.String()) }
return nil, &configError{fmt.Sprintf("unknown option %q", key.String())}
}
if conf.Listen == "" {
conf.Listen = "127.0.0.1:8053"
}
if conf.Path == "" {
conf.Path = "/resolve"
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{"8.8.8.8:53", "8.8.4.4:53"}
}
if conf.Timeout == 0 {
conf.Timeout = 10
@@ -67,14 +68,14 @@ func loadConfig(path string) (*config, error) {
}
if (conf.Cert != "") != (conf.Key != "") {
return nil, &configError { "You must specify both -cert and -key to enable TLS" }
return nil, &configError{"You must specify both -cert and -key to enable TLS"}
}
return conf, nil
}
type configError struct {
err string
err string
}
func (e *configError) Error() string {

2
doh-server/doh-server.conf
View File

@@ -8,7 +8,7 @@ cert = ""
key = ""
# HTTP path for resolve application
path = "/resolve"
path = "/dns-query"
# Upstream DNS resolver
# If multiple servers are specified, a random one will be chosen each time.

193
doh-server/google.go Normal file
View File

@@ -0,0 +1,193 @@
/*
DNS-over-HTTPS
Copyright (C) 2017-2018 Star Brilliant <m13253@hotmail.com>
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/
package main
import (
"encoding/json"
"fmt"
"log"
"net"
"net/http"
"strconv"
"strings"
"../json-dns"
"github.com/miekg/dns"
"golang.org/x/net/idna"
)
func (s *Server) parseRequestGoogle(w http.ResponseWriter, r *http.Request) *DNSRequest {
name := r.FormValue("name")
if name == "" {
return &DNSRequest{
errcode: 400,
errtext: "Invalid argument value: \"name\"",
}
}
name = strings.ToLower(name)
if punycode, err := idna.ToASCII(name); err == nil {
name = punycode
} else {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Invalid argument value: \"name\" = %q (%s)", name, err.Error()),
}
}
rrTypeStr := r.FormValue("type")
rrType := uint16(1)
if rrTypeStr == "" {
} else if v, err := strconv.ParseUint(rrTypeStr, 10, 16); err == nil {
rrType = uint16(v)
} else if v, ok := dns.StringToType[strings.ToUpper(rrTypeStr)]; ok {
rrType = v
} else {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Invalid argument value: \"type\" = %q", rrTypeStr),
}
}
cdStr := r.FormValue("cd")
cd := false
if cdStr == "1" || cdStr == "true" {
cd = true
} else if cdStr == "0" || cdStr == "false" || cdStr == "" {
} else {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Invalid argument value: \"cd\" = %q", cdStr),
}
}
ednsClientSubnet := r.FormValue("edns_client_subnet")
ednsClientFamily := uint16(0)
ednsClientAddress := net.IP(nil)
ednsClientNetmask := uint8(255)
if ednsClientSubnet != "" {
if ednsClientSubnet == "0/0" {
ednsClientSubnet = "0.0.0.0/0"
}
slash := strings.IndexByte(ednsClientSubnet, '/')
if slash < 0 {
ednsClientAddress = net.ParseIP(ednsClientSubnet)
if ednsClientAddress == nil {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Invalid argument value: \"edns_client_subnet\" = %q", ednsClientSubnet),
}
}
if ipv4 := ednsClientAddress.To4(); ipv4 != nil {
ednsClientFamily = 1
ednsClientAddress = ipv4
ednsClientNetmask = 24
} else {
ednsClientFamily = 2
ednsClientNetmask = 48
}
} else {
ednsClientAddress = net.ParseIP(ednsClientSubnet[:slash])
if ednsClientAddress == nil {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Invalid argument value: \"edns_client_subnet\" = %q", ednsClientSubnet),
}
}
if ipv4 := ednsClientAddress.To4(); ipv4 != nil {
ednsClientFamily = 1
ednsClientAddress = ipv4
} else {
ednsClientFamily = 2
}
netmask, err := strconv.ParseUint(ednsClientSubnet[slash+1:], 10, 8)
if err != nil {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Invalid argument value: \"edns_client_subnet\" = %q", ednsClientSubnet),
}
}
ednsClientNetmask = uint8(netmask)
}
} else {
ednsClientAddress = s.findClientIP(r)
if ednsClientAddress == nil {
ednsClientNetmask = 0
} else if ipv4 := ednsClientAddress.To4(); ipv4 != nil {
ednsClientFamily = 1
ednsClientAddress = ipv4
ednsClientNetmask = 24
} else {
ednsClientFamily = 2
ednsClientNetmask = 48
}
}
msg := new(dns.Msg)
msg.SetQuestion(dns.Fqdn(name), rrType)
msg.CheckingDisabled = cd
opt := new(dns.OPT)
opt.Hdr.Name = "."
opt.Hdr.Rrtype = dns.TypeOPT
opt.SetUDPSize(4096)
opt.SetDo(true)
if ednsClientAddress != nil {
edns0Subnet := new(dns.EDNS0_SUBNET)
edns0Subnet.Code = dns.EDNS0SUBNET
edns0Subnet.Family = ednsClientFamily
edns0Subnet.SourceNetmask = ednsClientNetmask
edns0Subnet.SourceScope = 0
edns0Subnet.Address = ednsClientAddress
opt.Option = append(opt.Option, edns0Subnet)
}
msg.Extra = append(msg.Extra, opt)
return &DNSRequest{
request: msg,
isTailored: ednsClientSubnet == "",
}
}
func (s *Server) generateResponseGoogle(w http.ResponseWriter, r *http.Request, req *DNSRequest) {
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)
return
}
w.Header().Set("Content-Type", "application/json; charset=UTF-8")
if respJSON.HaveTTL {
if req.isTailored {
w.Header().Set("Cache-Control", "public, max-age="+strconv.Itoa(int(respJSON.LeastTTL)))
} else {
w.Header().Set("Cache-Control", "private, max-age="+strconv.Itoa(int(respJSON.LeastTTL)))
}
w.Header().Set("Expires", respJSON.EarliestExpires.Format(http.TimeFormat))
}
if respJSON.Status == dns.RcodeServerFailure {
w.WriteHeader(503)
}
w.Write(respStr)
}

144
doh-server/ietf.go Normal file
View File

@@ -0,0 +1,144 @@
/*
DNS-over-HTTPS
Copyright (C) 2017-2018 Star Brilliant <m13253@hotmail.com>
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/
package main
import (
"encoding/base64"
"fmt"
"io/ioutil"
"log"
"net/http"
"strconv"
"time"
"../json-dns"
"github.com/miekg/dns"
)
func (s *Server) parseRequestIETF(w http.ResponseWriter, r *http.Request) *DNSRequest {
requestBase64 := r.FormValue("dns")
requestBinary, err := base64.StdEncoding.DecodeString(requestBase64)
if err != nil {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Invalid argument value: \"dns\" = %q", requestBase64),
}
}
if len(requestBinary) == 0 && r.Header.Get("Content-Type") == "application/dns-udpwireformat" {
requestBinary, err = ioutil.ReadAll(r.Body)
if err != nil {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Failed to read request body (%s)", err.Error()),
}
}
}
if len(requestBinary) == 0 {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("Invalid argument value: \"dns\""),
}
}
msg := new(dns.Msg)
err = msg.Unpack(requestBinary)
if err != nil {
return &DNSRequest{
errcode: 400,
errtext: fmt.Sprintf("DNS packet parse failure (%s)", err.Error()),
}
}
msg.Id = dns.Id()
opt := msg.IsEdns0()
if opt == nil {
opt = new(dns.OPT)
opt.Hdr.Name = "."
opt.Hdr.Rrtype = dns.TypeOPT
opt.SetUDPSize(4096)
opt.SetDo(false)
msg.Extra = append(msg.Extra, opt)
}
var edns0Subnet *dns.EDNS0_SUBNET
for _, option := range opt.Option {
if option.Option() == dns.EDNS0SUBNET {
edns0Subnet = option.(*dns.EDNS0_SUBNET)
break
}
}
isTailored := edns0Subnet == nil
if edns0Subnet == nil {
ednsClientFamily := uint16(0)
ednsClientAddress := s.findClientIP(r)
ednsClientNetmask := uint8(255)
if ednsClientAddress == nil {
ednsClientNetmask = 0
} else if ipv4 := ednsClientAddress.To4(); ipv4 != nil {
ednsClientFamily = 1
ednsClientAddress = ipv4
ednsClientNetmask = 24
} else {
ednsClientFamily = 2
ednsClientNetmask = 48
}
edns0Subnet = new(dns.EDNS0_SUBNET)
edns0Subnet.Code = dns.EDNS0SUBNET
edns0Subnet.Family = ednsClientFamily
edns0Subnet.SourceNetmask = ednsClientNetmask
edns0Subnet.SourceScope = 0
edns0Subnet.Address = ednsClientAddress
opt.Option = append(opt.Option, edns0Subnet)
}
return &DNSRequest{
request: msg,
isTailored: isTailored,
}
}
func (s *Server) generateResponseIETF(w http.ResponseWriter, r *http.Request, req *DNSRequest) {
respJSON := jsonDNS.Marshal(req.response)
req.response.Id = 0
respBytes, err := req.response.Pack()
if err != nil {
log.Println(err)
jsonDNS.FormatError(w, fmt.Sprintf("DNS packet construct failure (%s)", err.Error()), 500)
return
}
w.Header().Set("Content-Type", "application/dns-udpwireformat")
now := time.Now().Format(http.TimeFormat)
w.Header().Set("Date", now)
w.Header().Set("Last-Modified", now)
if respJSON.HaveTTL {
if req.isTailored {
w.Header().Set("Cache-Control", "public, max-age="+strconv.Itoa(int(respJSON.LeastTTL)))
} else {
w.Header().Set("Cache-Control", "private, max-age="+strconv.Itoa(int(respJSON.LeastTTL)))
}
w.Header().Set("Expires", respJSON.EarliestExpires.Format(http.TimeFormat))
}
if respJSON.Status == dns.RcodeServerFailure {
w.WriteHeader(503)
}
w.Write(respBytes)
}

34
doh-server/main.go
View File

@@ -1,24 +1,24 @@
/*
DNS-over-HTTPS
Copyright (C) 2017 Star Brilliant <m13253@hotmail.com>
DNS-over-HTTPS
Copyright (C) 2017-2018 Star Brilliant <m13253@hotmail.com>
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/
package main

243
doh-server/server.go
View File

@@ -1,61 +1,67 @@
/*
DNS-over-HTTPS
Copyright (C) 2017 Star Brilliant <m13253@hotmail.com>
DNS-over-HTTPS
Copyright (C) 2017-2018 Star Brilliant <m13253@hotmail.com>
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/
package main
import (
"encoding/json"
"fmt"
"math/rand"
"log"
"math/rand"
"net"
"net/http"
"os"
"strconv"
"strings"
"time"
"golang.org/x/net/idna"
"../json-dns"
"github.com/gorilla/handlers"
"github.com/miekg/dns"
"../json-dns"
)
type Server struct {
conf *config
udpClient *dns.Client
tcpClient *dns.Client
servemux *http.ServeMux
conf *config
udpClient *dns.Client
tcpClient *dns.Client
servemux *http.ServeMux
}
type DNSRequest struct {
request *dns.Msg
response *dns.Msg
isTailored bool
errcode int
errtext string
}
func NewServer(conf *config) (s *Server) {
s = &Server {
s = &Server{
conf: conf,
udpClient: &dns.Client {
Net: "udp",
udpClient: &dns.Client{
Net: "udp",
Timeout: time.Duration(conf.Timeout) * time.Second,
},
tcpClient: &dns.Client {
Net: "tcp",
tcpClient: &dns.Client{
Net: "tcp",
Timeout: time.Duration(conf.Timeout) * time.Second,
},
servemux: http.NewServeMux(),
@@ -71,151 +77,76 @@ func (s *Server) Start() error {
}
if s.conf.Cert != "" || s.conf.Key != "" {
return http.ListenAndServeTLS(s.conf.Listen, s.conf.Cert, s.conf.Key, servemux)
} else {
return http.ListenAndServe(s.conf.Listen, servemux)
}
return http.ListenAndServe(s.conf.Listen, servemux)
}
func (s *Server) handlerFunc(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json; charset=UTF-8")
w.Header().Set("Server", "DNS-over-HTTPS/1.0 (+https://github.com/m13253/dns-over-https)")
w.Header().Set("X-Powered-By", "DNS-over-HTTPS/1.0 (+https://github.com/m13253/dns-over-https)")
name := r.FormValue("name")
if name == "" {
jsonDNS.FormatError(w, "Invalid argument value: \"name\"", 400)
return
if r.Form == nil {
const maxMemory = 32 << 20 // 32 MB
r.ParseMultipartForm(maxMemory)
}
name = strings.ToLower(name)
if punycode, err := idna.ToASCII(name); err == nil {
name = punycode
} else {
jsonDNS.FormatError(w, fmt.Sprintf("Invalid argument value: \"name\" = %q (%s)", name, err.Error()), 400)
return
contentType := r.Header.Get("Content-Type")
if ct := r.FormValue("ct"); ct != "" {
contentType = ct
}
rrTypeStr := r.FormValue("type")
rrType := uint16(1)
if rrTypeStr == "" {
} else if v, err := strconv.ParseUint(rrTypeStr, 10, 16); err == nil {
rrType = uint16(v)
} else if v, ok := dns.StringToType[strings.ToUpper(rrTypeStr)]; ok {
rrType = v
} else {
jsonDNS.FormatError(w, fmt.Sprintf("Invalid argument value: \"type\" = %q", rrTypeStr), 400)
return
}
cdStr := r.FormValue("cd")
cd := false
if cdStr == "1" || cdStr == "true" {
cd = true
} else if cdStr == "0" || cdStr == "false" || cdStr == "" {
} else {
jsonDNS.FormatError(w, fmt.Sprintf("Invalid argument value: \"cd\" = %q", cdStr), 400)
return
}
ednsClientSubnet := r.FormValue("edns_client_subnet")
ednsClientFamily := uint16(0)
ednsClientAddress := net.IP(nil)
ednsClientNetmask := uint8(255)
if ednsClientSubnet != "" {
if ednsClientSubnet == "0/0" {
ednsClientSubnet = "0.0.0.0/0"
if contentType == "" {
// Guess request Content-Type based on other parameters
if r.FormValue("name") != "" {
contentType = "application/x-www-form-urlencoded"
} else if r.FormValue("dns") != "" {
contentType = "application/dns-udpwireformat"
}
slash := strings.IndexByte(ednsClientSubnet, '/')
if slash < 0 {
ednsClientAddress = net.ParseIP(ednsClientSubnet)
if ednsClientAddress == nil {
jsonDNS.FormatError(w, fmt.Sprintf("Invalid argument value: \"edns_client_subnet\" = %q", ednsClientSubnet), 400)
return
}
if ipv4 := ednsClientAddress.To4(); ipv4 != nil {
ednsClientFamily = 1
ednsClientAddress = ipv4
ednsClientNetmask = 24
} else {
ednsClientFamily = 2
ednsClientNetmask = 48
}
} else {
ednsClientAddress = net.ParseIP(ednsClientSubnet[:slash])
if ednsClientAddress == nil {
jsonDNS.FormatError(w, fmt.Sprintf("Invalid argument value: \"edns_client_subnet\" = %q", ednsClientSubnet), 400)
return
}
if ipv4 := ednsClientAddress.To4(); ipv4 != nil {
ednsClientFamily = 1
ednsClientAddress = ipv4
} else {
ednsClientFamily = 2
}
netmask, err := strconv.ParseUint(ednsClientSubnet[slash + 1:], 10, 8)
if err != nil {
jsonDNS.FormatError(w, fmt.Sprintf("Invalid argument value: \"edns_client_subnet\" = %q (%s)", ednsClientSubnet, err.Error()), 400)
return
}
ednsClientNetmask = uint8(netmask)
}
var responseType string
for _, responseCandidate := range strings.Split(r.Header.Get("Accept"), ",") {
responseCandidate = strings.ToLower(strings.SplitN(responseCandidate, ";", 2)[0])
if responseCandidate == "application/json" {
responseType = "application/json"
break
} else if responseCandidate == "application/dns-udpwireformat" {
responseType = "application/dns-udpwireformat"
break
}
} else {
ednsClientAddress = s.findClientIP(r)
if ednsClientAddress == nil {
ednsClientNetmask = 0
} else if ipv4 := ednsClientAddress.To4(); ipv4 != nil {
ednsClientFamily = 1
ednsClientAddress = ipv4
ednsClientNetmask = 24
} else {
ednsClientFamily = 2
ednsClientNetmask = 48
}
if responseType == "" {
// Guess response Content-Type based on request Content-Type
if contentType == "application/x-www-form-urlencoded" {
responseType = "application/json"
} else if contentType == "application/dns-udpwireformat" {
responseType = "application/dns-udpwireformat"
}
}
msg := new(dns.Msg)
msg.SetQuestion(dns.Fqdn(name), rrType)
msg.CheckingDisabled = cd
opt := new(dns.OPT)
opt.Hdr.Name = "."
opt.Hdr.Rrtype = dns.TypeOPT
opt.SetUDPSize(4096)
opt.SetDo(true)
if ednsClientAddress != nil {
edns0Subnet := new(dns.EDNS0_SUBNET)
edns0Subnet.Code = dns.EDNS0SUBNET
edns0Subnet.Family = ednsClientFamily
edns0Subnet.SourceNetmask = ednsClientNetmask
edns0Subnet.SourceScope = 0
edns0Subnet.Address = ednsClientAddress
opt.Option = append(opt.Option, edns0Subnet)
var req *DNSRequest
if contentType == "application/x-www-form-urlencoded" {
req = s.parseRequestGoogle(w, r)
} else if contentType == "application/dns-udpwireformat" {
req = s.parseRequestIETF(w, r)
} else {
jsonDNS.FormatError(w, fmt.Sprintf("Invalid argument value: \"ct\" = %q", contentType), 400)
return
}
if req.errcode != 0 {
jsonDNS.FormatError(w, req.errtext, req.errcode)
return
}
msg.Extra = append(msg.Extra, opt)
resp, err := s.doDNSQuery(msg)
var err error
req.response, err = s.doDNSQuery(req.request)
if err != nil {
jsonDNS.FormatError(w, fmt.Sprintf("DNS query failure (%s)", err.Error()), 503)
return
}
respJson := jsonDNS.Marshal(resp)
respStr, err := json.Marshal(respJson)
if err != nil {
log.Println(err)
jsonDNS.FormatError(w, fmt.Sprintf("DNS packet parse failure (%s)", err.Error()), 500)
return
}
if respJson.HaveTTL {
if ednsClientSubnet != "" {
w.Header().Set("Cache-Control", "public, max-age=" + strconv.Itoa(int(respJson.LeastTTL)))
} else {
w.Header().Set("Cache-Control", "private, max-age=" + strconv.Itoa(int(respJson.LeastTTL)))
}
w.Header().Set("Expires", respJson.EarliestExpires.Format(http.TimeFormat))
if contentType == "application/x-www-form-urlencoded" {
s.generateResponseGoogle(w, r, req)
} else if contentType == "application/dns-udpwireformat" {
s.generateResponseIETF(w, r, req)
}
if respJson.Status == dns.RcodeServerFailure {
w.WriteHeader(503)
}
w.Write(respStr)
}
func (s *Server) findClientIP(r *http.Request) net.IP {
@@ -248,9 +179,9 @@ func (s *Server) findClientIP(r *http.Request) net.IP {
}
func (s *Server) doDNSQuery(msg *dns.Msg) (resp *dns.Msg, err error) {
num_servers := len(s.conf.Upstream)
numServers := len(s.conf.Upstream)
for i := uint(0); i < s.conf.Tries; i++ {
server := s.conf.Upstream[rand.Intn(num_servers)]
server := s.conf.Upstream[rand.Intn(numServers)]
if !s.conf.TCPOnly {
resp, _, err = s.udpClient.Exchange(msg, server)
if err == dns.ErrTruncated {