26 changed files with 1526 additions and 776 deletions
--- a/.gitignore
+++ b/.gitignore
@ -1,5 +1,31 @@
 # Compiled Object files, Static and Dynamic libs (Shared Objects)
 *.o
 *.a
 *.so
 # Folders
 _obj
 _test
 # Architecture specific extensions/prefixes
 *.[568vq]
 [568vq].out
 *.cgo1.go
 *.cgo2.c
 _cgo_defun.c
 _cgo_gotypes.go
 _cgo_export.*
 _testmain.go
 *.exe
 *.test
 *.prof
 *~
 *.swp
 *.json
 *.txt
 gdns*
 *.key
 *.crt
 client.yaml
 server.yaml
--- a/675
+++ b/675
@ -0,0 +1,675 @@
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007
 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.
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            How to Apply These Terms to Your New Programs
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 free software which everyone can redistribute and change under these terms.
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 to attach them to the start of each source file to most effectively
 state the exclusion of warranty; and each file should have at least
 the "copyright" line and a pointer to where the full notice is found.
    {one line to give the program's name and a brief idea of what it does.}
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    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 Also add information on how to contact you by electronic and paper mail.
  If the program does terminal interaction, make it output a short
 notice like this when it starts in an interactive mode:
    {project}  Copyright (C) {year}  {fullname}
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.
 The hypothetical commands `show w' and `show c' should show the appropriate
 parts of the General Public License.  Of course, your program's commands
 might be different; for a GUI interface, you would use an "about box".
  You should also get your employer (if you work as a programmer) or school,
 if any, to sign a "copyright disclaimer" for the program, if necessary.
 For more information on this, and how to apply and follow the GNU GPL, see
 <http://www.gnu.org/licenses/>.
  The GNU General Public License does not permit incorporating your program
 into proprietary programs.  If your program is a subroutine library, you
 may consider it more useful to permit linking proprietary applications with
 the library.  If this is what you want to do, use the GNU Lesser General
 Public License instead of this License.  But first, please read
 <http://www.gnu.org/philosophy/why-not-lgpl.html>.
--- a/README.md
+++ b/README.md
@ -1,12 +1,27 @@
-gdns
+# gdns
-====
+a dns proxy server write by go
 Features
 ========
 support tcp, udp, tls, DoH(dns over https/http2)
 Usage
 =======
 ```bash
 go get github.com/fangdingjun/gdns
 cp $GOPATH/src/github.com/fangdingjun/gdns/config_example.yaml config.yaml
 vim config.yaml
 $GOPATH/bin/gdns -c config.yaml -log_level DEBUG
 ```
 Third-part library
 ==================
 use 
 [dns](https://github.com/miekg/dns)
 library to parse the dns message
 a dns forward proxy write by go
 **Features**
 - support listen tcp and udp protocol
 - support configure different domains to forward to different upstream servers
 - support tcp or udp to communicate to upstream servers
 - support ip blacklist to filter unwanted dns reply
 - support google https dns
--- a/cache.go
+++ b/cache.go
@ -1,84 +0,0 @@
 package main
 import (
 	"crypto/md5"
 	"encoding/binary"
 	"encoding/hex"
 	"github.com/miekg/dns"
 	"log"
 	"sync"
 	"time"
 )
 type cache struct {
 	m    map[string]*elem
 	lock *sync.RWMutex
 	ttl  int64
 	max  int
 }
 type elem struct {
 	m *dns.Msg
 	t int64
 }
 func newCache(max int, ttl int64) *cache {
 	return &cache{
 		max:  max,
 		ttl:  ttl,
 		m:    map[string]*elem{},
 		lock: new(sync.RWMutex),
 	}
 }
 func key(m *dns.Msg) string {
 	d := m.Question[0].Name
 	b := []byte(d)
 	b1 := make([]byte, 4)
 	binary.BigEndian.PutUint16(b1[0:], m.Question[0].Qclass)
 	binary.BigEndian.PutUint16(b1[2:], m.Question[0].Qtype)
 	b = append(b, b1...)
 	h := md5.New()
 	h.Write(b)
 	s1 := hex.EncodeToString(h.Sum(nil))
 	return s1
 }
 func (c *cache) get(m *dns.Msg) *dns.Msg {
 	c.lock.RLock()
 	defer c.lock.RUnlock()
 	k := key(m)
 	if m1, ok := c.m[k]; ok {
 		t := time.Now().Unix()
 		if t < m1.t {
 			return m1.m
 		}
 	}
 	return nil
 }
 func (c *cache) set(m *dns.Msg) {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 	if len(c.m) >= c.max {
 		log.Printf("clean the old cache")
 		c.cleanOld()
 	}
 	k := key(m)
 	c.m[k] = &elem{
 		m.Copy(),
 		time.Now().Unix() + c.ttl,
 	}
 }
 // must hold the write lock
 func (c *cache) cleanOld() {
 	t1 := time.Now().Unix()
 	for k, v := range c.m {
 		if v.t >= t1 {
 			delete(c.m, k)
 		}
 	}
 }
--- a/cache_test.go
+++ b/cache_test.go
@ -1,58 +0,0 @@
 package main
 import (
 	"github.com/miekg/dns"
 	"testing"
 	"time"
 )
 func TestCache(t *testing.T) {
 	c := newCache(5, 2)
 	tests := map[string]uint16{
 		"www.google.com":    dns.TypeA,
 		"www.google.com.hk": dns.TypeA,
 		"www.google.com.sg": dns.TypeA,
 		"www.google.com.it": dns.TypeA,
 		"www.google.com.de": dns.TypeA,
 		"www.google.com.cn": dns.TypeA,
 	}
 	var datas []*dns.Msg
 	for k, v := range tests {
 		m1 := new(dns.Msg)
 		m1.SetQuestion(k, v)
 		datas = append(datas, m1)
 	}
 	for i := 0; i < 3; i++ {
 		c.set(datas[i])
 	}
 	for i := 0; i < 3; i++ {
 		m2 := c.get(datas[i])
 		if m2 == nil {
 			t.Errorf("store cache failed")
 		}
 		if m2.Question[0].Name != datas[i].Question[0].Name {
 			t.Errorf("cache error")
 		}
 	}
 	time.Sleep(3 * time.Second)
 	for i := 0; i < 3; i++ {
 		m2 := c.get(datas[i])
 		if m2 != nil {
 			t.Errorf("cache not expired")
 		}
 	}
 	for i := 3; i < 6; i++ {
 		c.set(datas[i])
 	}
 	if len(c.m) > len(datas) {
 		t.Errorf("old cache not purged")
 	}
 }
--- a/cfg.go
+++ b/cfg.go
@ -1,144 +0,0 @@
 package main
 import (
 	"bufio"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"strings"
 )
 type item map[string]int
 func (i item) has(s string) bool {
 	if _, ok := i[s]; ok {
 		return true
 	}
 	return false
 }
 func (it item) match(s string) bool {
 	iis := strings.Split(s, ".")
 	for i := 0; i < len(iis); i++ {
 		ii := strings.Join(iis[i:], ".")
 		if _, ok := it[ii]; ok {
 			return true
 		}
 	}
 	return false
 }
 type addr struct {
 	network string
 	addr    string
 }
 // Rule present a forward rule
 type Rule struct {
 	DomainlistFile string `json:"domain_list_file"`
 	domains        item
 	ServersString  []string `json:"servers"`
 	servers        []addr
 }
 type cfg struct {
 	EnableCache    bool     `json:"enable_cache"`
 	Listen         []string `json:"listen"`
 	User           string   `json:"user"`
 	Group          string   `json:"group"`
 	listen         []addr
 	ServersString  []string `json:"default_servers"`
 	servers        []addr
 	Timeout        int      `json:"timeout"`
 	TTL            int      `json:"ttl"`
 	BlacklistFiles []string `json:"blacklist_ips"`
 	blacklistIps   item
 	Rules          []Rule `json:"rules"`
 }
 func parseCfg(fn string) (*cfg, error) {
 	c := cfg{}
 	buf, err := ioutil.ReadFile(fn)
 	if err != nil {
 		return nil, err
 	}
 	err = json.Unmarshal(buf, &c)
 	if err != nil {
 		return nil, err
 	}
 	var adr []addr
 	for _, a := range c.ServersString {
 		a1 := parseAddr(a)
 		if a1.network != "" {
 			adr = append(adr, a1)
 		}
 	}
 	c.servers = adr
 	var ll []addr
 	for _, a := range c.Listen {
 		a1 := parseAddr(a)
 		if a1.network != "" {
 			ll = append(ll, a1)
 		}
 	}
 	c.listen = ll
 	l1 := make(item)
 	for _, a := range c.BlacklistFiles {
 		parseFile(a, &l1)
 	}
 	c.blacklistIps = l1
 	for i, r := range c.Rules {
 		l2 := make(item)
 		parseFile(r.DomainlistFile, &l2)
 		c.Rules[i].domains = l2
 		var adr1 []addr
 		for _, a := range r.ServersString {
 			a1 := parseAddr(a)
 			if a1.network != "" {
 				adr1 = append(adr1, a1)
 			}
 		}
 		c.Rules[i].servers = adr1
 	}
 	return &c, nil
 }
 func parseAddr(addr1 string) addr {
 	a := strings.SplitN(addr1, ":", 2)
 	if len(a) != 2 {
 		fmt.Printf("addr error")
 		return addr{"", ""}
 	}
 	return addr{a[0], a[1]}
 }
 func parseFile(fn string, i *item) {
 	ii := *i
 	fp, err := os.Open(fn)
 	if err != nil {
 		fmt.Printf("open failed: %s\n", err)
 		return
 	}
 	defer fp.Close()
 	r := bufio.NewReader(fp)
 	for {
 		line, err := r.ReadString('\n')
 		l := strings.Trim(line, " \r\n\t")
 		if err != nil {
 			if l != "" && l[0] != '#' {
 				ii[l] = 1
 			}
 			break
 		}
 		if l == "" || l[0] == '#' {
 			continue
 		}
 		ii[l] = 1
 	}
 }
--- a/cfg_test.go
+++ b/cfg_test.go
@ -1,19 +0,0 @@
 package main
 import (
 	"fmt"
 	"os"
 	"testing"
 )
 func TestCfg(t *testing.T) {
 	os.Chdir("example_config")
 	c, err := parseCfg("config.json")
 	if err != nil {
 		t.Fatalf("%s\n", err)
 	}
 	fmt.Printf("%+v\n", c)
 	fmt.Printf("%v\n", c.Rules[0].domains.match("google.com"))
 	fmt.Printf("%v\n", c.Rules[0].domains.match("www.ip.cn"))
 }
--- a/client_https.go
+++ b/client_https.go
@ -0,0 +1,59 @@
 package main
 import (
 	"bytes"
 	"context"
 	"fmt"
 	"io"
 	"net/http"
 	"time"
 	"github.com/miekg/dns"
 )
 type httpclient struct {
 	Net        string
 	Timeout    time.Duration
 	HTTPClient *http.Client
 }
 func (c *httpclient) Exchange(msg *dns.Msg, upstream string) (*dns.Msg, int, error) {
 	data, err := msg.Pack()
 	if err != nil {
 		return nil, 0, err
 	}
 	req, err := http.NewRequest("POST", upstream, bytes.NewReader(data))
 	if err != nil {
 		return nil, 0, err
 	}
 	req.Header.Set("Content-Type", dnsMsgType)
 	ctx, cancel := context.WithTimeout(context.Background(), c.Timeout)
 	defer cancel()
 	req = req.WithContext(ctx)
 	resp, err := c.HTTPClient.Do(req)
 	if err != nil {
 		return nil, 0, err
 	}
 	defer resp.Body.Close()
 	if resp.StatusCode != http.StatusOK {
 		return nil, 0, fmt.Errorf("http error %d", resp.StatusCode)
 	}
 	data, err = io.ReadAll(resp.Body)
 	if err != nil {
 		return nil, 0, err
 	}
 	m := new(dns.Msg)
 	if err = m.Unpack(data); err != nil {
 		return nil, 0, err
 	}
 	return m, 0, nil
 }
--- a/config.go
+++ b/config.go
@ -0,0 +1,33 @@
 package main
 import (
 	"os"
 	"github.com/go-yaml/yaml"
 )
 type conf struct {
 	UpstreamServers  []string `yaml:"upstream_servers"`
 	BootstrapServers []string `yaml:"bootstrap_servers"`
 	Listen           []listen `yaml:"listen"`
 	UpstreamTimeout  int      `yaml:"upstream_timeout"`
 	UpstreamInsecure bool     `yaml:"upstream_insecure"`
 }
 type listen struct {
 	Addr string `yaml:"addr"`
 	Cert string `yaml:"cert"`
 	Key  string `yaml:"key"`
 }
 func loadConfig(f string) (*conf, error) {
 	data, err := os.ReadFile(f)
 	if err != nil {
 		return nil, err
 	}
 	var c conf
 	if err := yaml.Unmarshal(data, &c); err != nil {
 		return nil, err
 	}
 	return &c, nil
 }
--- a/config_example.yaml
+++ b/config_example.yaml
@ -0,0 +1,40 @@
 # upstream servers
 # support DoH(DNS over https/http2), tcp, udp and tls(dns over tls)
 upstream_servers:
  - https://cloudflare-dns.com/dns-query
  - tcp://1.0.0.1:53
  - udp://1.0.0.1:53
  - tls://cloudflare-dns:853
 # bootstrap dns server,
 # this used to resolve the domain name used in Doh and TLS,
 # not needed if you don't use DoH and tls
 bootstrap_servers:
  - tcp://1.0.0.1:53
  - udp://1.0.0.1:53
 # listen ports
 listen:
  -
    addr: tcp://0.0.0.0:1053
    cert:
    key:
  -
    addr: udp://0.0.0.0:1053
    cert: 
    key:
  -
    addr: https://0.0.0.0:1054/dns-query
    cert: server.crt
    key: server.key
  -
    addr: tls://0.0.0.1:1055
    cert: server.crt
    key: server.key
 # timeout for upstream server, second
 upstream_timeout: 3
 # check upstream certificate or not
 # if you use self signed certificate, set this to true
 upstream_insecure: false
--- a/example_config/config.json
+++ b/example_config/config.json
@ -1,20 +0,0 @@
 {
    "listen":["tcp:0.0.0.0:8053","udp::8053"],
    "default_servers":["tcp:208.67.222.222:53","tcp:8.8.8.8:53"],
    "user":"nobody",
    "group":"nogroup",
    "ttl":3600,
    "timeout":1,
    "enable_cache":false,
    "blacklist_ips":["ip.txt"],
    "rules":[
        {
            "domain_list_file":"domain1.txt",
            "servers":["tcp:4.2.2.2:53"]
        },
        {
            "domain_list_file":"domain2.txt",
            "servers":["tcp:8.8.4.4:53","https:74.125.200.100"]
        }
    ]
 }
--- a/example_config/domain1.txt
+++ b/example_config/domain1.txt
@ -1,4 +0,0 @@
 ww.goole.com
 ip.cn
 taobao.com
 a.cn
--- a/example_config/domain2.txt
+++ b/example_config/domain2.txt
@ -1,3 +0,0 @@
 a.com
 b.org
 c.net
--- a/example_config/ip.txt
+++ b/example_config/ip.txt
@ -1,2 +0,0 @@
 1.2.3.4
 2.21.2.2
--- a/go.mod
+++ b/go.mod
@ -0,0 +1,22 @@
 module github.com/fangdingjun/gdns
 go 1.17
 require (
 	github.com/fangdingjun/go-log/v5 v5.0.0
 	github.com/fangdingjun/protolistener v0.0.0-20210804081554-626e6590d6e7
 	github.com/go-yaml/yaml v2.1.0+incompatible
 	github.com/miekg/dns v1.1.43
 	golang.org/x/net v0.0.0-20210726213435-c6fcb2dbf985
 )
 require (
 	github.com/kr/pretty v0.3.0 // indirect
 	github.com/pires/go-proxyproto v0.6.1 // indirect
 	golang.org/x/crypto v0.0.0-20210711020723-a769d52b0f97 // indirect
 	golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c // indirect
 	golang.org/x/term v0.0.0-20210615171337-6886f2dfbf5b // indirect
 	golang.org/x/text v0.3.6 // indirect
 	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )
--- a/go.sum
+++ b/go.sum
@ -0,0 +1,51 @@
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/fangdingjun/go-log/v5 v5.0.0 h1:vdh9Bk9C4ZFL6KoO6rII73zQIyaLf7hFdBvucO/ckiE=
 github.com/fangdingjun/go-log/v5 v5.0.0/go.mod h1:V012Oxo0/pSbccX4OFSp9MJglXwNsZo2ByBBorr7zzM=
 github.com/fangdingjun/protolistener v0.0.0-20210804081554-626e6590d6e7 h1:z5NlLvUNbGZxQhtUZELvIorAqpDmcIhGQXE5GdO7+5I=
 github.com/fangdingjun/protolistener v0.0.0-20210804081554-626e6590d6e7/go.mod h1:ljbjhI4fVrT5GwMu1iBhWTZwLJSqsXKwKlGKas5GudM=
 github.com/go-yaml/yaml v2.1.0+incompatible h1:RYi2hDdss1u4YE7GwixGzWwVo47T8UQwnTLB6vQiq+o=
 github.com/go-yaml/yaml v2.1.0+incompatible/go.mod h1:w2MrLa16VYP0jy6N7M5kHaCkaLENm+P+Tv+MfurjSw0=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pretty v0.3.0 h1:WgNl7dwNpEZ6jJ9k1snq4pZsg7DOEN8hP9Xw0Tsjwk0=
 github.com/kr/pretty v0.3.0/go.mod h1:640gp4NfQd8pI5XOwp5fnNeVWj67G7CFk/SaSQn7NBk=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/miekg/dns v1.1.43 h1:JKfpVSCB84vrAmHzyrsxB5NAr5kLoMXZArPSw7Qlgyg=
 github.com/miekg/dns v1.1.43/go.mod h1:+evo5L0630/F6ca/Z9+GAqzhjGyn8/c+TBaOyfEl0V4=
 github.com/pires/go-proxyproto v0.6.0/go.mod h1:Odh9VFOZJCf9G8cLW5o435Xf1J95Jw9Gw5rnCjcwzAY=
 github.com/pires/go-proxyproto v0.6.1 h1:EBupykFmo22SDjv4fQVQd2J9NOoLPmyZA/15ldOGkPw=
 github.com/pires/go-proxyproto v0.6.1/go.mod h1:Odh9VFOZJCf9G8cLW5o435Xf1J95Jw9Gw5rnCjcwzAY=
 github.com/rogpeppe/go-internal v1.6.1 h1:/FiVV8dS/e+YqF2JvO3yXRFbBLTIuSDkuC7aBOAvL+k=
 github.com/rogpeppe/go-internal v1.6.1/go.mod h1:xXDCJY+GAPziupqXw64V24skbSoqbTEfhy4qGm1nDQc=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210711020723-a769d52b0f97 h1:/UOmuWzQfxxo9UtlXMwuQU8CMgg1eZXqTRwkSQJWKOI=
 golang.org/x/crypto v0.0.0-20210711020723-a769d52b0f97/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210726213435-c6fcb2dbf985 h1:4CSI6oo7cOjJKajidEljs9h+uP0rRZBPPPhcCbj5mw8=
 golang.org/x/net v0.0.0-20210726213435-c6fcb2dbf985/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c h1:5KslGYwFpkhGh+Q16bwMP3cOontH8FOep7tGV86Y7SQ=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210303074136-134d130e1a04/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c h1:F1jZWGFhYfh0Ci55sIpILtKKK8p3i2/krTr0H1rg74I=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210615171337-6886f2dfbf5b h1:9zKuko04nR4gjZ4+DNjHqRlAJqbJETHwiNKDqTfOjfE=
 golang.org/x/term v0.0.0-20210615171337-6886f2dfbf5b/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6 h1:aRYxNxv6iGQlyVaZmk6ZgYEDa+Jg18DxebPSrd6bg1M=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
--- a/httpdns.go
+++ b/httpdns.go
@ -1,186 +0,0 @@
 package main
 import (
 	"crypto/tls"
 	"encoding/json"
 	"fmt"
 	"github.com/miekg/dns"
 	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
 	"sync"
 	"time"
 )
 // ServerAddr is Google dns server ip
 var ServerAddr = "74.125.200.100"
 var queryIPApi = "https://www.simicloud.com/media/httpbin/ip"
 // HTTPDns struct
 type HTTPDns struct {
 	myip string
 	l    sync.Mutex
 }
 func (h *HTTPDns) getMyIP() string {
 	if h.myip != "" {
 		return h.myip
 	}
 	go h.queryMyIP()
 	return ""
 }
 type ipAPI struct {
 	IP string `json:"origin"`
 }
 func (h *HTTPDns) queryMyIP() {
 	h.l.Lock()
 	defer h.l.Unlock()
 	if h.myip != "" {
 		//fmt.Printf("myip: %s\n", h.myip)
 		return
 	}
 	//fmt.Println("get ip...")
 	res, err := http.Get(queryIPApi)
 	if err != nil {
 		//fmt.Println(err)
 		return
 	}
 	defer res.Body.Close()
 	d, err := ioutil.ReadAll(res.Body)
 	if err != nil {
 		//fmt.Println(err)
 		return
 	}
 	//fmt.Printf("%s\n", string(d))
 	ip := ipAPI{}
 	err = json.Unmarshal(d, &ip)
 	if err != nil {
 		//fmt.Println(err)
 		return
 	}
 	//fmt.Printf("got: %s\n", ip.Ip)
 	h.myip = ip.IP
 }
 func (h *HTTPDns) getMyNet() string {
 	ip := h.getMyIP()
 	if ip == "" {
 		return ""
 	}
 	mask := net.IPv4Mask(255, 255, 255, 0)
 	ipByte := net.ParseIP(ip)
 	ipnet := net.IPNet{ipByte.Mask(mask), mask}
 	return ipnet.String()
 }
 // Exchange send query to server and return the response
 func (h *HTTPDns) Exchange(m *dns.Msg, addr string) (*dns.Msg, time.Duration, error) {
 	name := m.Question[0].Name
 	t := dns.TypeToString[m.Question[0].Qtype]
 	mynet := h.getMyNet()
 	r, err := query(name, t, mynet, "", addr)
 	if err != nil {
 		return nil, 0, err
 	}
 	m1 := new(dns.Msg)
 	m1.SetRcode(m, r.Status)
 	for _, rr := range r.Answer {
 		_rr := fmt.Sprintf("%s %d IN %s %s", rr.Name, rr.TTL,
 			dns.TypeToString[uint16(rr.Type)], rr.Data)
 		an, err := dns.NewRR(_rr)
 		if err != nil {
 			return nil, 0, err
 		}
 		m1.Answer = append(m1.Answer, an)
 	}
 	m1.Truncated = r.TC
 	m1.RecursionDesired = r.RD
 	m1.RecursionAvailable = r.RA
 	m1.AuthenticatedData = r.AD
 	m1.CheckingDisabled = r.CD
 	return m1, 0, nil
 }
 // DefaultHTTPDnsClient default http dns client
 var DefaultHTTPDnsClient = &HTTPDns{}
 // Response represent the dns response from server
 type Response struct {
 	Status           int
 	TC               bool
 	RD               bool
 	RA               bool
 	AD               bool
 	CD               bool
 	Question         []RR
 	Answer           []RR
 	Additional       []RR
 	EDNSClientSubnet string `json:"edns_client_subnet"`
 	Comment          string
 }
 // RR represent the RR record
 type RR struct {
 	Name string `json:"name"`
 	Type int    `json:"type"`
 	TTL  int
 	Data string `json:"data"`
 }
 var httpclient = &http.Client{
 	Timeout: 5 * time.Second,
 	Transport: &http.Transport{
 		TLSClientConfig:     &tls.Config{ServerName: "dns.google.com"},
 		TLSHandshakeTimeout: 3 * time.Second,
 	},
 }
 func query(name, t, ednsClientSubnet, padding, srvAddr string) (*Response, error) {
 	srvaddr := ServerAddr
 	if srvAddr != "" {
 		srvaddr = srvAddr
 	}
 	v := url.Values{}
 	v.Add("name", name)
 	v.Add("type", t)
 	if ednsClientSubnet != "" {
 		v.Add("edns_client_subnet", ednsClientSubnet)
 	}
 	if padding != "" {
 		v.Add("random_padding", padding)
 	}
 	u := fmt.Sprintf("https://%s/resolve?%s", srvaddr, v.Encode())
 	r, _ := http.NewRequest("GET", u, nil)
 	r.Host = "dns.google.com"
 	//r.URL.Host = "dns.google.com"
 	res, err := httpclient.Do(r)
 	if err != nil {
 		return nil, err
 	}
 	defer res.Body.Close()
 	data, err := ioutil.ReadAll(res.Body)
 	if err != nil {
 		return nil, err
 	}
 	d := Response{}
 	err = json.Unmarshal(data, &d)
 	if err != nil {
 		return nil, err
 	}
 	return &d, nil
 }
--- a/httpdns_test.go
+++ b/httpdns_test.go
@ -1,80 +0,0 @@
 package main
 import (
 	"encoding/json"
 	"fmt"
 	"github.com/miekg/dns"
 	"io/ioutil"
 	"net"
 	"net/http"
 	"testing"
 	"time"
 )
 // MyIP my ip
 type MyIP struct {
 	IP string `json:"origin"`
 }
 func myip() string {
 	res, err := http.Get("https://www.simicloud.com/media/httpbin/ip")
 	if err != nil {
 		return ""
 	}
 	defer res.Body.Close()
 	data, err := ioutil.ReadAll(res.Body)
 	if err != nil {
 		return ""
 	}
 	ip := MyIP{}
 	err = json.Unmarshal(data, &ip)
 	if err != nil {
 		return ""
 	}
 	return ip.IP
 }
 func TestQuery(t *testing.T) {
 	m := net.IPv4Mask(255, 255, 255, 0)
 	ip1 := net.ParseIP(myip())
 	ipnet := net.IPNet{ip1.Mask(m), m}
 	r, err := query("www.taobao.com", "a", ipnet.String(), "", "")
 	if err != nil {
 		t.Error(err)
 	}
 	fmt.Printf("%+v\n", r)
 	r, err = query("www.taobao.com", "a", "", "", "")
 	if err != nil {
 		t.Error(err)
 	}
 	fmt.Printf("%+v\n", r)
 }
 func TestHttpsQuery(t *testing.T) {
 	m := new(dns.Msg)
 	m.SetQuestion("www.taobao.com", dns.TypeA)
 	m2, _, err := DefaultHTTPDnsClient.Exchange(m, ServerAddr)
 	if err != nil {
 		t.Error(err)
 	}
 	fmt.Println(m2)
 	time.Sleep(1 * time.Second)
 	m2, _, err = DefaultHTTPDnsClient.Exchange(m, ServerAddr)
 	if err != nil {
 		t.Error(err)
 	}
 	fmt.Println(m2)
 }
 func TestGetMyIP(t *testing.T) {
 	a := DefaultHTTPDnsClient.getMyIP()
 	time.Sleep(4 * time.Second)
 	a = DefaultHTTPDnsClient.getMyIP()
 	if a == "" {
 		t.Errorf("get ip failed")
 	}
 }
--- a/main.go
+++ b/main.go
@ -0,0 +1,67 @@
 package main
 import (
 	"flag"
 	"fmt"
 	"os"
 	"os/signal"
 	"syscall"
 	log "github.com/fangdingjun/go-log/v5"
 )
 var cfg *conf
 func main() {
 	var configfile string
 	var logFileCount int
 	var logFileSize int64
 	var loglevel string
 	var logfile string
 	flag.StringVar(&logfile, "log_file", "", "log file, default stdout")
 	flag.IntVar(&logFileCount, "log_count", 10, "max count of log to keep")
 	flag.Int64Var(&logFileSize, "log_size", 10, "max log file size MB")
 	flag.StringVar(&loglevel, "log_level", "INFO",
 		"log level, values:\nOFF, FATAL, PANIC, ERROR, WARN, INFO, DEBUG")
 	flag.StringVar(&configfile, "c", "gdns.yaml", "config file")
 	flag.Parse()
 	if logfile != "" {
 		log.Default.Out = &log.FixedSizeFileWriter{
 			MaxCount: logFileCount,
 			Name:     logfile,
 			MaxSize:  logFileSize * 1024 * 1024,
 		}
 	}
 	if loglevel != "" {
 		lv, err := log.ParseLevel(loglevel)
 		if err != nil {
 			fmt.Fprintln(os.Stderr, err)
 			os.Exit(1)
 		}
 		log.Default.Level = lv
 	}
 	_cfg, err := loadConfig(configfile)
 	if err != nil {
 		log.Fatal(err)
 	}
 	cfg = _cfg
 	if cfg.UpstreamTimeout == 0 {
 		cfg.UpstreamTimeout = 5
 	}
 	initDNSClient(cfg)
 	log.Debugf("%+v", cfg)
 	makeServers(cfg)
 	ch := make(chan os.Signal, 2)
 	signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM)
 	s := <-ch
 	log.Errorf("received signal %s, exit...", s)
 	log.Println("exit.")
 }
--- a/middleware.go
+++ b/middleware.go
@ -0,0 +1,56 @@
 package main
 import (
 	"net/http"
 	log "github.com/fangdingjun/go-log/v5"
 )
 type logHandler struct {
 	status int
 	w      http.ResponseWriter
 	size   int
 }
 func (lh *logHandler) WriteHeader(status int) {
 	lh.status = status
 	lh.w.WriteHeader(status)
 }
 func (lh *logHandler) Write(buf []byte) (int, error) {
 	lh.size += len(buf)
 	return lh.w.Write(buf)
 }
 func (lh *logHandler) Header() http.Header {
 	return lh.w.Header()
 }
 func (lh *logHandler) Status() int {
 	if lh.status != 0 {
 		return lh.status
 	}
 	return 200
 }
 var _ http.ResponseWriter = &logHandler{}
 // LogHandler is a log middleware
 // record request log
 func LogHandler(handler http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		defer func() {
 			if err := recover(); err != nil {
 				log.Error(err)
 				w.WriteHeader(http.StatusInternalServerError)
 				log.Infof("\"%s - %s %s %s\" - %d %d \"%s\"",
 					r.RemoteAddr, r.Method, r.RequestURI, r.Proto, 500, 0, r.UserAgent())
 			}
 		}()
 		lh := &logHandler{w: w}
 		handler.ServeHTTP(lh, r)
 		log.Infof("\"%s - %s %s %s\" - %d %d \"%s\"",
 			r.RemoteAddr, r.Method, r.RequestURI, r.Proto, lh.Status(), lh.size, r.UserAgent())
 	})
 }
--- a/routers.go
+++ b/routers.go
@ -1,134 +0,0 @@
 package main
 import (
 	"errors"
 	"github.com/miekg/dns"
 	//"log"
 	"strings"
 	"time"
 )
 type routers struct {
 	c     *cfg
 	tcp   *dns.Client
 	udp   *dns.Client
 	cache *cache
 }
 func (r *routers) checkBlacklist(m *dns.Msg) bool {
 	if m.Rcode != dns.RcodeSuccess {
 		// not success, not in blacklist
 		return false
 	}
 	for _, rr := range m.Answer {
 		var ip = ""
 		if t, ok := rr.(*dns.A); ok {
 			ip = t.A.String()
 		} else if t, ok := rr.(*dns.AAAA); ok {
 			ip = t.AAAA.String()
 		}
 		if ip != "" && r.c.blacklistIps.has(ip) {
 			//log.Printf("%s is in blacklist.\n", ip)
 			return true
 		}
 	}
 	return false
 }
 type dnsClient interface {
 	Exchange(*dns.Msg, string) (*dns.Msg, time.Duration, error)
 }
 func (r *routers) query(m *dns.Msg, servers []addr) (*dns.Msg, error) {
 	var up dnsClient
 	var lastErr error
 	if r.c.EnableCache {
 		// query cache
 		m2 := r.cache.get(m)
 		if m2 != nil {
 			//log.Printf("query %s, reply from cache\n", m.Question[0].Name)
 			m2.Id = m.Id
 			return m2, nil
 		}
 	}
 	for _, srv := range servers {
 		switch srv.network {
 		case "tcp":
 			up = r.tcp
 		case "udp":
 			up = r.udp
 		case "https":
 			up = DefaultHTTPDnsClient
 		default:
 			up = r.udp
 		}
 		//log.Printf("query %s use %s:%s\n", m.Question[0].Name, srv.network, srv.addr)
 		m1, _, err := up.Exchange(m, srv.addr)
 		if err == nil && !r.checkBlacklist(m) {
 			if m1.Rcode == dns.RcodeSuccess && r.c.EnableCache {
 				// store to cache
 				r.cache.set(m1)
 			}
 			return m1, err
 		}
 		//log.Println(err)
 		lastErr = err
 	}
 	if lastErr == nil {
 		// this happens when ip in blacklist
 		lastErr = errors.New("timeout")
 	}
 	// return last error
 	return nil, lastErr
 }
 // ServeDNS implements dns.Handler interface
 func (r *routers) ServeDNS(w dns.ResponseWriter, m *dns.Msg) {
 	domain := m.Question[0].Name
 	d := strings.Trim(domain, ".")
 	for _, rule := range r.c.Rules {
 		if rule.domains.match(d) {
 			m1, err := r.query(m, rule.servers)
 			if err == nil {
 				w.WriteMsg(m1)
 				return
 			}
 			//log.Println(err)
 		}
 	}
 	// no match or failed, fallback to default
 	m1, err := r.query(m, r.c.servers)
 	if err != nil {
 		//log.Println(err)
 		dns.HandleFailed(w, m)
 	} else {
 		w.WriteMsg(m1)
 	}
 }
 func initRouters(c *cfg) {
 	var cache1 *cache = nil
 	if c.EnableCache {
 		cache1 = newCache(1000, int64(c.TTL)) // cache 5 hours
 	}
 	router := &routers{
 		c,
 		&dns.Client{Net: "tcp", Timeout: time.Duration(c.Timeout) * time.Second},
 		&dns.Client{Net: "udp", Timeout: time.Duration(c.Timeout) * time.Second},
 		cache1,
 	}
 	dns.Handle(".", router)
 }
--- a/server.go
+++ b/server.go
@ -1,50 +1,158 @@
 package main
 import (
-	"flag"
+	"crypto/tls"
-	"github.com/fangdingjun/gpp/util"
+	"fmt"
-	"github.com/miekg/dns"
+	"net"
-	"log"
+	"net/http"
-	"os"
+	"net/url"
-	"time"
+	"strconv"
 	log "github.com/fangdingjun/go-log/v5"
 	"github.com/fangdingjun/protolistener"
 )
-func initListeners(c *cfg) {
+type server struct {
-	for _, a := range c.listen {
+	addr      *url.URL
-		log.Printf("Listen on %s %s...\n", a.network, a.addr)
+	cert      string
-		s := &dns.Server{Addr: a.addr, Net: a.network}
+	key       string
-		go func(s *dns.Server) {
+	upstreams []*url.URL
-			err := s.ListenAndServe()
+}
 func (srv *server) serve() {
 	switch srv.addr.Scheme {
 	case "udp":
 		srv.serveUDP()
 	case "tcp":
 		srv.serveTCP()
 	case "tls":
 		srv.serveTLS()
 	case "http":
 		srv.serveHTTP()
 	case "https":
 		srv.serveHTTP()
 	default:
 		log.Fatalf("unsupported type %s", srv.addr.Scheme)
 	}
 }
 func (srv *server) serveUDP() {
 	ip, port, _ := net.SplitHostPort(srv.addr.Host)
 	_ip := net.ParseIP(ip)
 	_port, _ := strconv.Atoi(port)
 	udpconn, err := net.ListenUDP("udp", &net.UDPAddr{IP: _ip, Port: _port})
 	if err != nil {
 		log.Fatalf("listen udp error %s", err)
 	}
 	defer udpconn.Close()
 	buf := make([]byte, 4096)
 	for {
 		n, addr, err := udpconn.ReadFrom(buf)
 		if err != nil {
-				log.Println(err)
+			log.Debugln(err)
-				os.Exit(-1)
+			break
 		}
-		}(s)
+		buf1 := make([]byte, n)
 		copy(buf1, buf[:n])
 		go srv.handleUDP(buf1, addr, udpconn)
 	}
 }
-func main() {
+func (srv *server) serveTCP() {
-	var configFile string
+	l, err := net.Listen("tcp", srv.addr.Host)
 	if err != nil {
 		log.Fatalln("listen tcp", err)
 	}
 	defer l.Close()
 	log.Debugf("listen tcp://%s", l.Addr().String())
 	for {
 		conn, err := l.Accept()
 		if err != nil {
 			log.Debugln(err)
 			break
 		}
 		go srv.handleTCP(conn)
 	}
 }
-	flag.StringVar(&configFile, "c", "", "config file")
+func (srv *server) serveTLS() {
-	flag.Parse()
+	cert, err := tls.LoadX509KeyPair(srv.cert, srv.key)
 	if err != nil {
 		log.Fatalln("load certificate failed", err)
 	}
-	config, err := parseCfg(configFile)
+	l, err := net.Listen("tcp", srv.addr.Host)
 	if err != nil {
-		log.Println(err)
+		log.Fatalln("listen tls", err)
 		os.Exit(-1)
 	}
 	defer l.Close()
-	initRouters(config)
+	log.Debugf("listen tls://%s", l.Addr().String())
-	initListeners(config)
+	tl := tls.NewListener(protolistener.New(l), &tls.Config{
 		Certificates: []tls.Certificate{cert},
 		//NextProtos:   []string{"h2"},
 	})
-	// make a delay to make sure net bind completed before drop privilege
+	for {
-	time.Sleep(time.Second)
+		conn, err := tl.Accept()
 		if err != nil {
 			log.Debugln("tls accept", err)
 			break
 		}
 		go srv.handleTCP(conn)
 	}
 }
 func (srv *server) serveHTTP() {
 	log.Debugf("listen %s://%s", srv.addr.Scheme, srv.addr.Host)
 	l, err := net.Listen("tcp", srv.addr.Host)
 	if err != nil {
 		log.Fatalln("listen https", err)
 	}
 	defer l.Close()
-	err = util.DropPrivilege(config.User, config.Group)
+	httpsrv := &http.Server{
 		Handler: LogHandler(srv),
 	}
 	switch srv.addr.Scheme {
 	case "http":
 		err = httpsrv.Serve(protolistener.New(l))
 	case "https":
 		err = httpsrv.ServeTLS(protolistener.New(l), srv.cert, srv.key)
 	default:
 		err = fmt.Errorf("not supported %s", srv.addr.Scheme)
 	}
 	if err != nil {
-		log.Println(err)
+		log.Fatal(err)
 	}
 }
-	select {}
+func makeServers(c *conf) {
 	upstreams := []*url.URL{}
 	for _, a := range c.UpstreamServers {
 		u, err := url.Parse(a)
 		if err != nil {
 			log.Fatal(err)
 		}
 		upstreams = append(upstreams, u)
 	}
 	for _, l := range c.Listen {
 		u, err := url.Parse(l.Addr)
 		if err != nil {
 			log.Fatal(err)
 		}
 		srv := &server{
 			addr:      u,
 			cert:      l.Cert,
 			key:       l.Key,
 			upstreams: upstreams,
 		}
 		go srv.serve()
 	}
 }
--- a/server_https.go
+++ b/server_https.go
@ -0,0 +1,66 @@
 package main
 import (
 	"io"
 	"net/http"
 	log "github.com/fangdingjun/go-log/v5"
 	"github.com/miekg/dns"
 )
 const dnsMsgType = "application/dns-message"
 func (srv *server) handleHTTPReq(w http.ResponseWriter, r *http.Request) {
 	/*
 		ctype := r.Header.Get("content-type")
 		if !strings.HasPrefix(ctype, dnsMsgType) {
 			log.Errorf("request type %s, require %s", ctype, dnsMsgType)
 			http.Error(w, "dns message is required", http.StatusBadRequest)
 			return
 		}
 	*/
 	if r.ContentLength < 10 {
 		log.Errorf("message is too small, %v", r.ContentLength)
 		http.Error(w, "message is too small", http.StatusBadRequest)
 		return
 	}
 	data, err := io.ReadAll(r.Body)
 	if err != nil {
 		log.Errorln("read request body", err)
 		http.Error(w, "read request failed", http.StatusBadRequest)
 		return
 	}
 	msg := new(dns.Msg)
 	if err := msg.Unpack(data); err != nil {
 		log.Errorln("parse dns message", err)
 		http.Error(w, "parse dns message error", http.StatusBadRequest)
 		return
 	}
 	m, err := getResponseFromUpstream(msg, srv.upstreams)
 	if err != nil {
 		log.Debugln("query", msg.Question[0].String(), "timeout")
 		http.Error(w, "query upstream server failed", http.StatusServiceUnavailable)
 		return
 	}
 	for _, a := range m.Answer {
 		log.Debugln("result", a.String())
 	}
 	w.Header().Set("content-type", dnsMsgType)
 	d, _ := m.Pack()
 	if _, err := w.Write(d); err != nil {
 		log.Errorln(err)
 	}
 }
 func (srv *server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	if r.RequestURI != srv.addr.Path {
 		http.Error(w, "Path not found", http.StatusNotFound)
 		return
 	}
 	srv.handleHTTPReq(w, r)
 }
--- a/server_tcp.go
+++ b/server_tcp.go
@ -0,0 +1,35 @@
 package main
 import (
 	"net"
 	log "github.com/fangdingjun/go-log/v5"
 	"github.com/miekg/dns"
 )
 func (srv *server) handleTCP(c net.Conn) {
 	defer c.Close()
 	log.Debugln("tcp from", c.RemoteAddr())
 	conn := dns.Conn{Conn: c}
 	for {
 		msg, err := conn.ReadMsg()
 		if err != nil {
 			log.Debugln("tcp read message", err)
 			break
 		}
 		m, err := getResponseFromUpstream(msg, srv.upstreams)
 		if err != nil {
 			log.Debugln("query", msg.Question[0].String(), "timeout")
 			break
 		}
 		for _, a := range m.Answer {
 			log.Debugln("result", a.String())
 		}
 		if err := conn.WriteMsg(m); err != nil {
 			log.Errorln(err)
 			break
 		}
 	}
 }
--- a/server_udp.go
+++ b/server_udp.go
@ -0,0 +1,30 @@
 package main
 import (
 	"net"
 	log "github.com/fangdingjun/go-log/v5"
 	"github.com/miekg/dns"
 )
 func (srv *server) handleUDP(buf []byte, addr net.Addr, conn *net.UDPConn) {
 	msg := new(dns.Msg)
 	if err := msg.Unpack(buf); err != nil {
 		log.Debugln("udp parse msg", err)
 		return
 	}
 	m, err := getResponseFromUpstream(msg, srv.upstreams)
 	if err != nil {
 		log.Debugln("query", msg.Question[0].String(), "timeout")
 		return
 	}
 	for _, a := range m.Answer {
 		log.Debugln("result", a.String())
 	}
 	d, _ := m.Pack()
 	if _, err := conn.WriteTo(d, addr); err != nil {
 		log.Errorln(err)
 	}
 }
--- a/upstream.go
+++ b/upstream.go
@ -0,0 +1,201 @@
 package main
 import (
 	"bufio"
 	"context"
 	"crypto/tls"
 	"errors"
 	"fmt"
 	"net"
 	"net/http"
 	"net/url"
 	"os"
 	"strings"
 	"time"
 	log "github.com/fangdingjun/go-log/v5"
 	"github.com/miekg/dns"
 	"golang.org/x/net/http2"
 )
 var dnsClientTCP *dns.Client
 var dnsClientUDP *dns.Client
 var dnsClientTLS *dns.Client
 var dnsClientHTTPS *httpclient
 func getResponseFromUpstream(msg *dns.Msg, upstreams []*url.URL) (*dns.Msg, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(cfg.UpstreamTimeout+1)*time.Second)
 	defer cancel()
 	resch := make(chan *dns.Msg, len(upstreams))
 	for _, up := range upstreams {
 		go func(u *url.URL) {
 			m, err := queryUpstream(msg, u)
 			if err == nil {
 				resch <- m
 				return
 			}
 			log.Errorln(u.String(), err)
 		}(up)
 	}
 	var errmsg *dns.Msg
 	for i := 0; i < len(upstreams); i++ {
 		select {
 		case <-ctx.Done():
 			return nil, errors.New("time out")
 		case m := <-resch:
 			if m.MsgHdr.Rcode == dns.RcodeSuccess {
 				return m, nil
 			}
 			errmsg = m
 		}
 	}
 	if errmsg != nil {
 		return errmsg, nil
 	}
 	return nil, errors.New("empty result")
 }
 func queryUpstream(msg *dns.Msg, upstream *url.URL) (*dns.Msg, error) {
 	switch upstream.Scheme {
 	case "tcp":
 		return queryUpstreamTCP(msg, upstream)
 	case "https":
 		return queryUpstreamHTTPS(msg, upstream)
 	case "udp":
 		return queryUpstreamUDP(msg, upstream)
 	case "tls":
 		return queryUpstreamTLS(msg, upstream)
 	default:
 	}
 	return nil, errors.New("unknown upstream type")
 }
 func queryUpstreamUDP(msg *dns.Msg, upstream *url.URL) (*dns.Msg, error) {
 	m, _, err := dnsClientUDP.Exchange(msg, upstream.Host)
 	if err != nil {
 		log.Debugf("query udp error %s", err)
 	}
 	return m, err
 }
 func queryUpstreamTCP(msg *dns.Msg, upstream *url.URL) (*dns.Msg, error) {
 	m, _, err := dnsClientTCP.Exchange(msg, upstream.Host)
 	if err != nil {
 		log.Debugf("query tcp error %s", err)
 	}
 	return m, err
 }
 func queryUpstreamTLS(msg *dns.Msg, upstream *url.URL) (*dns.Msg, error) {
 	m, _, err := dnsClientTLS.Exchange(msg, upstream.Host)
 	if err != nil {
 		log.Debugf("query tls error %s", err)
 	}
 	return m, err
 }
 func queryUpstreamHTTPS(msg *dns.Msg, upstream *url.URL) (*dns.Msg, error) {
 	m, _, err := dnsClientHTTPS.Exchange(msg, upstream.String())
 	if err != nil {
 		log.Debugf("query https error %s", err)
 	}
 	return m, err
 }
 func initDNSClient(c *conf) {
 	var resolver = new(net.Resolver)
 	if len(c.BootstrapServers) > 0 {
 		log.Debugf("init dns client, bootstrap servers %v", c.BootstrapServers)
 		resolver = &net.Resolver{
 			Dial: func(ctx context.Context, network, addr string) (net.Conn, error) {
 				for _, a := range c.BootstrapServers {
 					u, _ := url.Parse(a)
 					conn, err := net.Dial(u.Scheme, u.Host)
 					if err == nil {
 						return conn, err
 					}
 				}
 				return nil, errors.New("dial failed")
 			},
 		}
 	}
 	dialer := &net.Dialer{
 		Resolver: resolver,
 	}
 	dnsClientTLS = &dns.Client{
 		Net:     "tcp-tls",
 		Timeout: time.Duration(c.UpstreamTimeout) * time.Second,
 		Dialer:  dialer,
 		TLSConfig: &tls.Config{
 			InsecureSkipVerify: c.UpstreamInsecure,
 		},
 	}
 	dnsClientUDP = &dns.Client{
 		Net:     "udp",
 		Timeout: time.Duration(c.UpstreamTimeout) * time.Second,
 	}
 	dnsClientTCP = &dns.Client{
 		Net:     "tcp",
 		Timeout: time.Duration(c.UpstreamTimeout) * time.Second,
 	}
 	dnsClientHTTPS = &httpclient{
 		Net:     "https",
 		Timeout: time.Duration(c.UpstreamTimeout) * time.Second,
 		HTTPClient: &http.Client{
 			Transport: &http2.Transport{
 				DialTLS: func(network, addr string, cfg *tls.Config) (net.Conn, error) {
 					log.Debugln("dial to", network, addr)
 					p := os.Getenv("https_proxy")
 					if p == "" {
 						p = os.Getenv("http_proxy")
 					}
 					if p == "" {
 						conn, err := tls.DialWithDialer(dialer, network, addr, cfg)
 						return conn, err
 					}
 					u, _ := url.Parse(p)
 					log.Debugf("dial to proxy %s", u.Host)
 					conn, err := net.Dial(network, u.Host)
 					if err != nil {
 						return nil, err
 					}
 					fmt.Fprintf(conn, "CONNECT %s HTTP/1.1\r\nHost: %s\r\n\r\n", addr, addr)
 					r := bufio.NewReader(conn)
 					line, err := r.ReadString('\n')
 					if err != nil {
 						return nil, err
 					}
 					ss := strings.Fields(line)
 					if ss[1] != "200" {
 						return nil, fmt.Errorf("http code %s", ss[1])
 					}
 					for {
 						line, err := r.ReadString('\n')
 						if err != nil {
 							return nil, err
 						}
 						line = strings.Trim(line, "\r\n")
 						if line == "" {
 							break
 						}
 					}
 					tlsconn := tls.Client(conn, cfg)
 					if err = tlsconn.Handshake(); err != nil {
 						return nil, err
 					}
 					return tlsconn, nil
 				},
 				TLSClientConfig: &tls.Config{
 					InsecureSkipVerify: c.UpstreamInsecure,
 					NextProtos:         []string{"h2"},
 				},
 			},
 		},
 	}
 }