Merge dns (#722)

* DNS: add clientip for specific nameserver

* Refactoring: DNS App

* DNS: add DNS over QUIC support

* Feat: add disableCache option for DNS

* Feat: add queryStrategy option for DNS

* Feat: add disableFallback & skipFallback option for DNS

* Feat: DNS hosts support multiple addresses

* Feat: DNS transport over TCP

* DNS: fix typo & refine code

* DNS: refine code

* Add disableFallbackIfMatch dns option

* Feat: routing and freedom outbound ignore Fake DNS

Turn off fake DNS for request sent from Routing and Freedom outbound.
Fake DNS now only apply to DNS outbound.
This is important for Android, where VPN service take over all system DNS
traffic and pass it to core.  "UseIp" option can be used in Freedom outbound
to avoid getting fake IP and fail connection.

* Fix test

* Fix dns return

* Fix local dns return empty

* Apply timeout to dns outbound

* Update app/dns/config.go

Co-authored-by: Loyalsoldier <10487845+loyalsoldier@users.noreply.github.com>
Co-authored-by: Ye Zhihao <vigilans@foxmail.com>
Co-authored-by: maskedeken <52683904+maskedeken@users.noreply.github.com>
Co-authored-by: V2Fly Team <51714622+vcptr@users.noreply.github.com>
Co-authored-by: CalmLong <37164399+calmlong@users.noreply.github.com>
Co-authored-by: Shelikhoo <xiaokangwang@outlook.com>
Co-authored-by: 秋のかえで <autmaple@protonmail.com>
Co-authored-by: 朱聖黎 <digglife@gmail.com>
Co-authored-by: rurirei <72071920+rurirei@users.noreply.github.com>
Co-authored-by: yuhan6665 <1588741+yuhan6665@users.noreply.github.com>
Co-authored-by: Arthur Morgan <4637240+badO1a5A90@users.noreply.github.com>
This commit is contained in:
世界 2021-10-16 21:02:51 +08:00 committed by GitHub
parent 5e606169f1
commit cd4631ce99
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
33 changed files with 2252 additions and 880 deletions

View file

@ -1,300 +0,0 @@
package dns
import (
"context"
"strings"
"sync"
"sync/atomic"
"time"
"golang.org/x/net/dns/dnsmessage"
"github.com/xtls/xray-core/common"
"github.com/xtls/xray-core/common/log"
"github.com/xtls/xray-core/common/net"
"github.com/xtls/xray-core/common/protocol/dns"
udp_proto "github.com/xtls/xray-core/common/protocol/udp"
"github.com/xtls/xray-core/common/session"
"github.com/xtls/xray-core/common/signal/pubsub"
"github.com/xtls/xray-core/common/task"
dns_feature "github.com/xtls/xray-core/features/dns"
"github.com/xtls/xray-core/features/routing"
"github.com/xtls/xray-core/transport/internet/udp"
)
type ClassicNameServer struct {
sync.RWMutex
name string
address net.Destination
ips map[string]record
requests map[uint16]dnsRequest
pub *pubsub.Service
udpServer *udp.Dispatcher
cleanup *task.Periodic
reqID uint32
clientIP net.IP
}
func NewClassicNameServer(address net.Destination, dispatcher routing.Dispatcher, clientIP net.IP) *ClassicNameServer {
// default to 53 if unspecific
if address.Port == 0 {
address.Port = net.Port(53)
}
s := &ClassicNameServer{
address: address,
ips: make(map[string]record),
requests: make(map[uint16]dnsRequest),
clientIP: clientIP,
pub: pubsub.NewService(),
name: strings.ToUpper(address.String()),
}
s.cleanup = &task.Periodic{
Interval: time.Minute,
Execute: s.Cleanup,
}
s.udpServer = udp.NewDispatcher(dispatcher, s.HandleResponse)
newError("DNS: created UDP client initialized for ", address.NetAddr()).AtInfo().WriteToLog()
return s
}
func (s *ClassicNameServer) Name() string {
return s.name
}
func (s *ClassicNameServer) Cleanup() error {
now := time.Now()
s.Lock()
defer s.Unlock()
if len(s.ips) == 0 && len(s.requests) == 0 {
return newError(s.name, " nothing to do. stopping...")
}
for domain, record := range s.ips {
if record.A != nil && record.A.Expire.Before(now) {
record.A = nil
}
if record.AAAA != nil && record.AAAA.Expire.Before(now) {
record.AAAA = nil
}
if record.A == nil && record.AAAA == nil {
delete(s.ips, domain)
} else {
s.ips[domain] = record
}
}
if len(s.ips) == 0 {
s.ips = make(map[string]record)
}
for id, req := range s.requests {
if req.expire.Before(now) {
delete(s.requests, id)
}
}
if len(s.requests) == 0 {
s.requests = make(map[uint16]dnsRequest)
}
return nil
}
func (s *ClassicNameServer) HandleResponse(ctx context.Context, packet *udp_proto.Packet) {
ipRec, err := parseResponse(packet.Payload.Bytes())
if err != nil {
newError(s.name, " fail to parse responded DNS udp").AtError().WriteToLog()
return
}
s.Lock()
id := ipRec.ReqID
req, ok := s.requests[id]
if ok {
// remove the pending request
delete(s.requests, id)
}
s.Unlock()
if !ok {
newError(s.name, " cannot find the pending request").AtError().WriteToLog()
return
}
var rec record
switch req.reqType {
case dnsmessage.TypeA:
rec.A = ipRec
case dnsmessage.TypeAAAA:
rec.AAAA = ipRec
}
elapsed := time.Since(req.start)
newError(s.name, " got answer: ", req.domain, " ", req.reqType, " -> ", ipRec.IP, " ", elapsed).AtInfo().WriteToLog()
if len(req.domain) > 0 && (rec.A != nil || rec.AAAA != nil) {
s.updateIP(req.domain, rec)
}
}
func (s *ClassicNameServer) updateIP(domain string, newRec record) {
s.Lock()
newError(s.name, " updating IP records for domain:", domain).AtDebug().WriteToLog()
rec := s.ips[domain]
updated := false
if isNewer(rec.A, newRec.A) {
rec.A = newRec.A
updated = true
}
if isNewer(rec.AAAA, newRec.AAAA) {
rec.AAAA = newRec.AAAA
updated = true
}
if updated {
s.ips[domain] = rec
}
if newRec.A != nil {
s.pub.Publish(domain+"4", nil)
}
if newRec.AAAA != nil {
s.pub.Publish(domain+"6", nil)
}
s.Unlock()
common.Must(s.cleanup.Start())
}
func (s *ClassicNameServer) newReqID() uint16 {
return uint16(atomic.AddUint32(&s.reqID, 1))
}
func (s *ClassicNameServer) addPendingRequest(req *dnsRequest) {
s.Lock()
defer s.Unlock()
id := req.msg.ID
req.expire = time.Now().Add(time.Second * 8)
s.requests[id] = *req
}
func (s *ClassicNameServer) sendQuery(ctx context.Context, domain string, option dns_feature.IPOption) {
newError(s.name, " querying DNS for: ", domain).AtDebug().WriteToLog(session.ExportIDToError(ctx))
reqs := buildReqMsgs(domain, option, s.newReqID, genEDNS0Options(s.clientIP))
for _, req := range reqs {
s.addPendingRequest(req)
b, _ := dns.PackMessage(req.msg)
udpCtx := context.Background()
if inbound := session.InboundFromContext(ctx); inbound != nil {
udpCtx = session.ContextWithInbound(udpCtx, inbound)
}
udpCtx = session.ContextWithContent(udpCtx, &session.Content{
Protocol: "dns",
})
udpCtx = log.ContextWithAccessMessage(udpCtx, &log.AccessMessage{
From: "DNS",
To: s.address,
Status: log.AccessAccepted,
Reason: "",
})
s.udpServer.Dispatch(udpCtx, s.address, b)
}
}
func (s *ClassicNameServer) findIPsForDomain(domain string, option dns_feature.IPOption) ([]net.IP, error) {
s.RLock()
record, found := s.ips[domain]
s.RUnlock()
if !found {
return nil, errRecordNotFound
}
var ips []net.Address
var lastErr error
if option.IPv4Enable {
a, err := record.A.getIPs()
if err != nil {
lastErr = err
}
ips = append(ips, a...)
}
if option.IPv6Enable {
aaaa, err := record.AAAA.getIPs()
if err != nil {
lastErr = err
}
ips = append(ips, aaaa...)
}
if len(ips) > 0 {
return toNetIP(ips), nil
}
if lastErr != nil {
return nil, lastErr
}
return nil, dns_feature.ErrEmptyResponse
}
// QueryIP implements Server.
func (s *ClassicNameServer) QueryIP(ctx context.Context, domain string, option dns_feature.IPOption) ([]net.IP, error) {
fqdn := Fqdn(domain)
ips, err := s.findIPsForDomain(fqdn, option)
if err != errRecordNotFound {
newError(s.name, " cache HIT ", domain, " -> ", ips).Base(err).AtDebug().WriteToLog()
log.Record(&log.DNSLog{Server: s.name, Domain: domain, Result: ips, Status: log.DNSCacheHit, Elapsed: 0, Error: err})
return ips, err
}
// ipv4 and ipv6 belong to different subscription groups
var sub4, sub6 *pubsub.Subscriber
if option.IPv4Enable {
sub4 = s.pub.Subscribe(fqdn + "4")
defer sub4.Close()
}
if option.IPv6Enable {
sub6 = s.pub.Subscribe(fqdn + "6")
defer sub6.Close()
}
done := make(chan interface{})
go func() {
if sub4 != nil {
select {
case <-sub4.Wait():
case <-ctx.Done():
}
}
if sub6 != nil {
select {
case <-sub6.Wait():
case <-ctx.Done():
}
}
close(done)
}()
s.sendQuery(ctx, fqdn, option)
start := time.Now()
for {
ips, err := s.findIPsForDomain(fqdn, option)
if err != errRecordNotFound {
log.Record(&log.DNSLog{Server: s.name, Domain: domain, Result: ips, Status: log.DNSQueried, Elapsed: time.Since(start), Error: err})
return ips, err
}
select {
case <-ctx.Done():
return nil, ctx.Err()
case <-done:
}
}
}