Feature: support DoH

This commit is contained in:
Dreamacro 2019-06-28 12:29:08 +08:00
parent 662038e40e
commit bc3fc0c840
8 changed files with 412 additions and 260 deletions

View File

@ -123,6 +123,7 @@ experimental:
# nameserver:
# - 114.114.114.114
# - tls://dns.rubyfish.cn:853 # dns over tls
# - https://1.1.1.1/dns-query # dns over https
# fallback: # concurrent request with nameserver, fallback used when GEOIP country isn't CN
# - tcp://1.1.1.1

View File

@ -475,9 +475,14 @@ func parseNameServer(servers []string) ([]dns.NameServer, error) {
case "tls":
host, err = hostWithDefaultPort(u.Host, "853")
dnsNetType = "tcp-tls" // DNS over TLS
case "https":
clearURL := url.URL{Scheme: "https", Host: u.Host, Path: u.Path}
host = clearURL.String()
dnsNetType = "https" // DNS over HTTPS
default:
return nil, fmt.Errorf("DNS NameServer[%d] unsupport scheme: %s", idx, u.Scheme)
}
if err != nil {
return nil, fmt.Errorf("DNS NameServer[%d] format error: %s", idx, err.Error())
}

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@ -2,270 +2,20 @@ package dns
import (
"context"
"crypto/tls"
"errors"
"net"
"strings"
"sync"
"time"
"github.com/Dreamacro/clash/common/cache"
"github.com/Dreamacro/clash/common/picker"
"github.com/Dreamacro/clash/component/fakeip"
C "github.com/Dreamacro/clash/constant"
D "github.com/miekg/dns"
geoip2 "github.com/oschwald/geoip2-golang"
)
var (
globalSessionCache = tls.NewLRUClientSessionCache(64)
mmdb *geoip2.Reader
once sync.Once
resolver *Resolver
)
type Resolver struct {
ipv6 bool
mapping bool
fakeip bool
pool *fakeip.Pool
fallback []*nameserver
main []*nameserver
cache *cache.Cache
}
type result struct {
Msg *D.Msg
Error error
}
func isIPRequest(q D.Question) bool {
if q.Qclass == D.ClassINET && (q.Qtype == D.TypeA || q.Qtype == D.TypeAAAA) {
return true
}
return false
}
func (r *Resolver) Exchange(m *D.Msg) (msg *D.Msg, err error) {
if len(m.Question) == 0 {
return nil, errors.New("should have one question at least")
}
q := m.Question[0]
cache, expireTime := r.cache.GetWithExpire(q.String())
if cache != nil {
msg = cache.(*D.Msg).Copy()
setMsgTTL(msg, uint32(expireTime.Sub(time.Now()).Seconds()))
return
}
defer func() {
if msg == nil {
return
}
putMsgToCache(r.cache, q.String(), msg)
if r.mapping {
ips := r.msgToIP(msg)
for _, ip := range ips {
putMsgToCache(r.cache, ip.String(), msg)
}
}
}()
isIPReq := isIPRequest(q)
if isIPReq {
msg, err = r.resolveIP(m)
return
}
msg, err = r.exchange(r.main, m)
return
}
func (r *Resolver) exchange(servers []*nameserver, m *D.Msg) (msg *D.Msg, err error) {
in := make(chan interface{})
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
defer cancel()
fast := picker.SelectFast(ctx, in)
wg := sync.WaitGroup{}
wg.Add(len(servers))
for _, server := range servers {
go func(s *nameserver) {
defer wg.Done()
msg, _, err := s.Client.Exchange(m, s.Address)
if err != nil || msg.Rcode != D.RcodeSuccess {
return
}
in <- msg
}(server)
}
// release in channel
go func() {
wg.Wait()
close(in)
}()
elm, exist := <-fast
if !exist {
return nil, errors.New("All DNS requests failed")
}
msg = elm.(*D.Msg)
return
}
func (r *Resolver) resolveIP(m *D.Msg) (msg *D.Msg, err error) {
msgCh := r.resolve(r.main, m)
if r.fallback == nil {
res := <-msgCh
msg, err = res.Msg, res.Error
return
}
fallbackMsg := r.resolve(r.fallback, m)
res := <-msgCh
if res.Error == nil {
if mmdb == nil {
return nil, errors.New("GeoIP can't use")
}
if ips := r.msgToIP(res.Msg); len(ips) != 0 {
if record, _ := mmdb.Country(ips[0]); record.Country.IsoCode == "CN" || record.Country.IsoCode == "" {
// release channel
go func() { <-fallbackMsg }()
msg = res.Msg
return msg, err
}
}
}
res = <-fallbackMsg
msg, err = res.Msg, res.Error
return
}
func (r *Resolver) ResolveIP(host string) (ip net.IP, err error) {
ip = net.ParseIP(host)
if ip != nil {
return ip, nil
}
query := &D.Msg{}
dnsType := D.TypeA
if r.ipv6 {
dnsType = D.TypeAAAA
}
query.SetQuestion(D.Fqdn(host), dnsType)
msg, err := r.Exchange(query)
if err != nil {
return nil, err
}
ips := r.msgToIP(msg)
if len(ips) == 0 {
return nil, errors.New("can't found ip")
}
ip = ips[0]
return
}
func (r *Resolver) msgToIP(msg *D.Msg) []net.IP {
ips := []net.IP{}
for _, answer := range msg.Answer {
switch ans := answer.(type) {
case *D.AAAA:
ips = append(ips, ans.AAAA)
case *D.A:
ips = append(ips, ans.A)
}
}
return ips
}
func (r *Resolver) IPToHost(ip net.IP) (string, bool) {
cache := r.cache.Get(ip.String())
if cache == nil {
return "", false
}
fqdn := cache.(*D.Msg).Question[0].Name
return strings.TrimRight(fqdn, "."), true
}
func (r *Resolver) resolve(client []*nameserver, msg *D.Msg) <-chan *result {
ch := make(chan *result)
go func() {
res, err := r.exchange(client, msg)
ch <- &result{Msg: res, Error: err}
}()
return ch
}
func (r *Resolver) IsMapping() bool {
return r.mapping
}
func (r *Resolver) IsFakeIP() bool {
return r.fakeip
}
type NameServer struct {
Net string
Addr string
}
type nameserver struct {
Client *D.Client
type client struct {
*D.Client
Address string
}
type Config struct {
Main, Fallback []NameServer
IPv6 bool
EnhancedMode EnhancedMode
Pool *fakeip.Pool
func (c *client) Exchange(m *D.Msg) (msg *D.Msg, err error) {
return c.ExchangeContext(context.Background(), m)
}
func transform(servers []NameServer) []*nameserver {
var ret []*nameserver
for _, s := range servers {
ret = append(ret, &nameserver{
Client: &D.Client{
Net: s.Net,
TLSConfig: &tls.Config{
ClientSessionCache: globalSessionCache,
// alpn identifier, see https://tools.ietf.org/html/draft-hoffman-dprive-dns-tls-alpn-00#page-6
NextProtos: []string{"dns"},
},
UDPSize: 4096,
},
Address: s.Addr,
})
}
return ret
}
func New(config Config) *Resolver {
once.Do(func() {
mmdb, _ = geoip2.Open(C.Path.MMDB())
})
r := &Resolver{
main: transform(config.Main),
ipv6: config.IPv6,
cache: cache.New(time.Second * 60),
mapping: config.EnhancedMode == MAPPING,
fakeip: config.EnhancedMode == FAKEIP,
pool: config.Pool,
}
if config.Fallback != nil {
r.fallback = transform(config.Fallback)
}
return r
func (c *client) ExchangeContext(ctx context.Context, m *D.Msg) (msg *D.Msg, err error) {
msg, _, err = c.Client.ExchangeContext(ctx, m, c.Address)
return
}

75
dns/doh.go Normal file
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@ -0,0 +1,75 @@
package dns
import (
"bytes"
"context"
"crypto/tls"
"io/ioutil"
"net/http"
D "github.com/miekg/dns"
)
const (
// dotMimeType is the DoH mimetype that should be used.
dotMimeType = "application/dns-message"
// dotPath is the URL path that should be used.
dotPath = "/dns-query"
)
var dohTransport = &http.Transport{
TLSClientConfig: &tls.Config{ClientSessionCache: globalSessionCache},
}
type dohClient struct {
url string
}
func (dc *dohClient) Exchange(m *D.Msg) (msg *D.Msg, err error) {
return dc.ExchangeContext(context.Background(), m)
}
func (dc *dohClient) ExchangeContext(ctx context.Context, m *D.Msg) (msg *D.Msg, err error) {
req, err := dc.newRequest(m)
if err != nil {
return nil, err
}
req = req.WithContext(ctx)
return dc.doRequest(req)
}
// newRequest returns a new DoH request given a dns.Msg.
func (dc *dohClient) newRequest(m *D.Msg) (*http.Request, error) {
buf, err := m.Pack()
if err != nil {
return nil, err
}
req, err := http.NewRequest(http.MethodPost, dc.url+"?bla=foo:443", bytes.NewReader(buf))
if err != nil {
return req, err
}
req.Header.Set("content-type", dotMimeType)
req.Header.Set("accept", dotMimeType)
return req, nil
}
func (dc *dohClient) doRequest(req *http.Request) (msg *D.Msg, err error) {
client := &http.Client{Transport: dohTransport}
resp, err := client.Do(req)
if err != nil {
return nil, err
}
defer resp.Body.Close()
buf, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil, err
}
msg = &D.Msg{}
err = msg.Unpack(buf)
return msg, err
}

289
dns/resolver.go Normal file
View File

@ -0,0 +1,289 @@
package dns
import (
"context"
"crypto/tls"
"errors"
"net"
"strings"
"sync"
"time"
"github.com/Dreamacro/clash/common/cache"
"github.com/Dreamacro/clash/common/picker"
"github.com/Dreamacro/clash/component/fakeip"
C "github.com/Dreamacro/clash/constant"
D "github.com/miekg/dns"
geoip2 "github.com/oschwald/geoip2-golang"
)
var (
globalSessionCache = tls.NewLRUClientSessionCache(64)
mmdb *geoip2.Reader
once sync.Once
)
type resolver interface {
Exchange(m *D.Msg) (msg *D.Msg, err error)
ExchangeContext(ctx context.Context, m *D.Msg) (msg *D.Msg, err error)
}
type result struct {
Msg *D.Msg
Error error
}
type Resolver struct {
ipv6 bool
mapping bool
fakeip bool
pool *fakeip.Pool
fallback []resolver
main []resolver
cache *cache.Cache
}
// ResolveIP request with TypeA and TypeAAAA, priority return TypeAAAA
func (r *Resolver) ResolveIP(host string) (ip net.IP, err error) {
ch := make(chan net.IP)
go func() {
ip, err := r.resolveIP(host, D.TypeA)
if err != nil {
close(ch)
return
}
ch <- ip
}()
ip, err = r.resolveIP(host, D.TypeAAAA)
if err == nil {
go func() {
<-ch
}()
return
}
ip, closed := <-ch
if closed {
return nil, errors.New("can't found ip")
}
return ip, nil
}
// ResolveIPv4 request with TypeA
func (r *Resolver) ResolveIPv4(host string) (ip net.IP, err error) {
ip = net.ParseIP(host)
if ip != nil {
return ip, nil
}
query := &D.Msg{}
query.SetQuestion(D.Fqdn(host), D.TypeA)
msg, err := r.Exchange(query)
if err != nil {
return nil, err
}
ips := r.msgToIP(msg)
if len(ips) == 0 {
return nil, errors.New("can't found ip")
}
ip = ips[0]
return
}
// Exchange a batch of dns request, and it use cache
func (r *Resolver) Exchange(m *D.Msg) (msg *D.Msg, err error) {
if len(m.Question) == 0 {
return nil, errors.New("should have one question at least")
}
q := m.Question[0]
cache, expireTime := r.cache.GetWithExpire(q.String())
if cache != nil {
msg = cache.(*D.Msg).Copy()
setMsgTTL(msg, uint32(expireTime.Sub(time.Now()).Seconds()))
return
}
defer func() {
if msg == nil {
return
}
putMsgToCache(r.cache, q.String(), msg)
if r.mapping {
ips := r.msgToIP(msg)
for _, ip := range ips {
putMsgToCache(r.cache, ip.String(), msg)
}
}
}()
isIPReq := isIPRequest(q)
if isIPReq {
msg, err = r.fallbackExchange(m)
return
}
msg, err = r.batchExchange(r.main, m)
return
}
// IPToHost return fake-ip or redir-host mapping host
func (r *Resolver) IPToHost(ip net.IP) (string, bool) {
cache := r.cache.Get(ip.String())
if cache == nil {
return "", false
}
fqdn := cache.(*D.Msg).Question[0].Name
return strings.TrimRight(fqdn, "."), true
}
func (r *Resolver) IsMapping() bool {
return r.mapping
}
func (r *Resolver) IsFakeIP() bool {
return r.fakeip
}
func (r *Resolver) batchExchange(clients []resolver, m *D.Msg) (msg *D.Msg, err error) {
in := make(chan interface{})
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
defer cancel()
fast := picker.SelectFast(ctx, in)
wg := sync.WaitGroup{}
wg.Add(len(clients))
for _, r := range clients {
go func(r resolver) {
defer wg.Done()
msg, err := r.ExchangeContext(ctx, m)
if err != nil || msg.Rcode != D.RcodeSuccess {
return
}
in <- msg
}(r)
}
// release in channel
go func() {
wg.Wait()
close(in)
}()
elm, exist := <-fast
if !exist {
return nil, errors.New("All DNS requests failed")
}
msg = elm.(*D.Msg)
return
}
func (r *Resolver) fallbackExchange(m *D.Msg) (msg *D.Msg, err error) {
msgCh := r.asyncExchange(r.main, m)
if r.fallback == nil {
res := <-msgCh
msg, err = res.Msg, res.Error
return
}
fallbackMsg := r.asyncExchange(r.fallback, m)
res := <-msgCh
if res.Error == nil {
if mmdb == nil {
return nil, errors.New("GeoIP can't use")
}
if ips := r.msgToIP(res.Msg); len(ips) != 0 {
if record, _ := mmdb.Country(ips[0]); record.Country.IsoCode == "CN" || record.Country.IsoCode == "" {
// release channel
go func() { <-fallbackMsg }()
msg = res.Msg
return msg, err
}
}
}
res = <-fallbackMsg
msg, err = res.Msg, res.Error
return
}
func (r *Resolver) resolveIP(host string, dnsType uint16) (ip net.IP, err error) {
query := &D.Msg{}
query.SetQuestion(D.Fqdn(host), dnsType)
msg, err := r.Exchange(query)
if err != nil {
return nil, err
}
ips := r.msgToIP(msg)
if len(ips) == 0 {
return nil, errors.New("can't found ip")
}
ip = ips[0]
return
}
func (r *Resolver) msgToIP(msg *D.Msg) []net.IP {
ips := []net.IP{}
for _, answer := range msg.Answer {
switch ans := answer.(type) {
case *D.AAAA:
ips = append(ips, ans.AAAA)
case *D.A:
ips = append(ips, ans.A)
}
}
return ips
}
func (r *Resolver) asyncExchange(client []resolver, msg *D.Msg) <-chan *result {
ch := make(chan *result)
go func() {
res, err := r.batchExchange(client, msg)
ch <- &result{Msg: res, Error: err}
}()
return ch
}
type NameServer struct {
Net string
Addr string
}
type Config struct {
Main, Fallback []NameServer
IPv6 bool
EnhancedMode EnhancedMode
Pool *fakeip.Pool
}
func New(config Config) *Resolver {
once.Do(func() {
mmdb, _ = geoip2.Open(C.Path.MMDB())
})
r := &Resolver{
main: transform(config.Main),
ipv6: config.IPv6,
cache: cache.New(time.Second * 60),
mapping: config.EnhancedMode == MAPPING,
fakeip: config.EnhancedMode == FAKEIP,
pool: config.Pool,
}
if len(config.Fallback) != 0 {
r.fallback = transform(config.Fallback)
}
return r
}

View File

@ -1,6 +1,7 @@
package dns
import (
"crypto/tls"
"encoding/json"
"errors"
"time"
@ -107,3 +108,34 @@ func setMsgTTL(msg *D.Msg, ttl uint32) {
extra.Header().Ttl = ttl
}
}
func isIPRequest(q D.Question) bool {
if q.Qclass == D.ClassINET && (q.Qtype == D.TypeA || q.Qtype == D.TypeAAAA) {
return true
}
return false
}
func transform(servers []NameServer) []resolver {
ret := []resolver{}
for _, s := range servers {
if s.Net == "https" {
ret = append(ret, &dohClient{url: s.Addr})
continue
}
ret = append(ret, &client{
Client: &D.Client{
Net: s.Net,
TLSConfig: &tls.Config{
ClientSessionCache: globalSessionCache,
// alpn identifier, see https://tools.ietf.org/html/draft-hoffman-dprive-dns-tls-alpn-00#page-6
NextProtos: []string{"dns"},
},
UDPSize: 4096,
},
Address: s.Addr,
})
}
return ret
}

2
go.mod
View File

@ -8,7 +8,7 @@ require (
github.com/go-chi/render v1.0.1
github.com/gofrs/uuid v3.2.0+incompatible
github.com/gorilla/websocket v1.4.0
github.com/miekg/dns v1.1.9
github.com/miekg/dns v1.1.14
github.com/oschwald/geoip2-golang v1.2.1
github.com/oschwald/maxminddb-golang v1.3.0 // indirect
github.com/sirupsen/logrus v1.4.1

4
go.sum
View File

@ -18,8 +18,8 @@ github.com/gorilla/websocket v1.4.0 h1:WDFjx/TMzVgy9VdMMQi2K2Emtwi2QcUQsztZ/zLaH
github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
github.com/konsorten/go-windows-terminal-sequences v1.0.1 h1:mweAR1A6xJ3oS2pRaGiHgQ4OO8tzTaLawm8vnODuwDk=
github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
github.com/miekg/dns v1.1.9 h1:OIdC9wT96RzuZMf2PfKRhFgsStHUUBZLM/lo1LqiM9E=
github.com/miekg/dns v1.1.9/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
github.com/miekg/dns v1.1.14 h1:wkQWn9wIp4mZbwW8XV6Km6owkvRPbOiV004ZM2CkGvA=
github.com/miekg/dns v1.1.14/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
github.com/oschwald/geoip2-golang v1.2.1 h1:3iz+jmeJc6fuCyWeKgtXSXu7+zvkxJbHFXkMT5FVebU=
github.com/oschwald/geoip2-golang v1.2.1/go.mod h1:0LTTzix/Ao1uMvOhAV4iLU0Lz7eCrP94qZWBTDKf0iE=
github.com/oschwald/maxminddb-golang v1.3.0 h1:oTh8IBSj10S5JNlUDg5WjJ1QdBMdeaZIkPEVfESSWgE=