Merge https://github.com/bigeagle/godns into domain-specs-name-server

# Conflicts:
#	handler.go
#	hosts.go
#	hosts_test.go
#	resolver.go
#	settings.go

etc/china.conf

@@ -0,0 +1,5 @@
+server=8.8.8.8#53
+server=127.0.0.1#5553
+
+server=/baidu.com/114.114.114.114
+# refer https://github.com/felixonmars/dnsmasq-china-list

etc/godns.conf

@@ -12,6 +12,8 @@ host = "127.0.0.1"
 port = 53
 
 [resolv]
+#Domain-specific nameservers configuration, formatting keep compatible with Dnsmasq
+server-list-file = "./etc/china.conf"
 resolv-file = "/etc/resolv.conf"
 timeout = 5  # 5 seconds
 # The concurrency interval request upstream recursive server
@@ -21,6 +23,7 @@ interval = 200 # 200 milliseconds
 setedns0 = false #Support for larger UDP DNS responses
 
 [redis]
+enable = true
 host = "127.0.0.1"
 port = 6379
 db = 0

handler.go

@@ -32,21 +32,12 @@ type GODNSHandler struct {
 func NewHandler() *GODNSHandler {
 
 	var (
-		clientConfig    *dns.ClientConfig
 		cacheConfig     CacheSettings
 		resolver        *Resolver
 		cache, negCache Cache
 	)
 
-	resolvConfig := settings.ResolvConfig
-	clientConfig, err := dns.ClientConfigFromFile(resolvConfig.ResolvFile)
-	if err != nil {
-		logger.Warn(":%s is not a valid resolv.conf file\n", resolvConfig.ResolvFile)
-		logger.Error(err.Error())
-		panic(err)
-	}
-	clientConfig.Timeout = resolvConfig.Timeout
-	resolver = &Resolver{clientConfig}
+	resolver = NewResolver(settings.ResolvConfig)
 
 	cacheConfig = settings.Cache
 	switch cacheConfig.Backend {

hosts.go

@@ -218,7 +218,7 @@ func (f *FileHosts) Refresh() {
 		}
 
 		ip := sli[0]
-		if !f.isIP(ip) {
+		if !isIP(ip) {
 			continue
 		}
 
@@ -241,14 +241,14 @@ func (f *FileHosts) clear() {
 	f.hosts = make(map[string]string)
 }
 
-func (f *FileHosts) isDomain(domain string) bool {
-	if f.isIP(domain) {
+func isDomain(domain string) bool {
+	if isIP(domain) {
 		return false
 	}
 	match, _ := regexp.MatchString(`^([a-zA-Z0-9\*]([a-zA-Z0-9\-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,6}$`, domain)
 	return match
 }
 
-func (f *FileHosts) isIP(ip string) bool {
+func isIP(ip string) bool {
 	return (net.ParseIP(ip) != nil)
 }

hosts_test.go

@@ -8,26 +8,24 @@ import (
 
 func TestHostDomainAndIP(t *testing.T) {
 	Convey("Test Host File Domain and IP regex", t, func() {
-		f := &FileHosts{}
-
 		Convey("1.1.1.1 should be IP and not domain", func() {
-			So(f.isIP("1.1.1.1"), ShouldEqual, true)
-			So(f.isDomain("1.1.1.1"), ShouldEqual, false)
+			So(isIP("1.1.1.1"), ShouldEqual, true)
+			So(isDomain("1.1.1.1"), ShouldEqual, false)
 		})
 
 		Convey("2001:470:20::2 should be IP and not domain", func() {
-			So(f.isIP("2001:470:20::2"), ShouldEqual, true)
-			So(f.isDomain("2001:470:20::2"), ShouldEqual, false)
+			So(isIP("2001:470:20::2"), ShouldEqual, true)
+			So(isDomain("2001:470:20::2"), ShouldEqual, false)
 		})
 
 		Convey("`host` should not be domain and not IP", func() {
-			So(f.isDomain("host"), ShouldEqual, false)
-			So(f.isIP("host"), ShouldEqual, false)
+			So(isDomain("host"), ShouldEqual, false)
+			So(isIP("host"), ShouldEqual, false)
 		})
 
 		Convey("`123.test` should be domain and not IP", func() {
-			So(f.isDomain("123.test"), ShouldEqual, true)
-			So(f.isIP("123.test"), ShouldEqual, false)
+			So(isDomain("123.test"), ShouldEqual, true)
+			So(isIP("123.test"), ShouldEqual, false)
 		})
 
 	})

resolver.go

@@ -1,8 +1,10 @@
 package main
 
 import (
+	"bufio"
 	"fmt"
-	"net"
+	"os"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -21,7 +23,92 @@ func (e ResolvError) Error() string {
 }
 
 type Resolver struct {
-	config *dns.ClientConfig
+	servers       []string
+	domain_server *suffixTreeNode
+	config        *ResolvSettings
+}
+
+func NewResolver(c ResolvSettings) *Resolver {
+	r := &Resolver{
+		servers:       []string{},
+		domain_server: newSuffixTreeRoot(),
+		config:        &c,
+	}
+
+	if len(c.ServerListFile) > 0 {
+		r.ReadServerListFile(c.ServerListFile)
+		// Debug("%v", r.servers)
+	}
+
+	if len(c.ResolvFile) > 0 {
+		clientConfig, err := dns.ClientConfigFromFile(c.ResolvFile)
+		if err != nil {
+			logger.Error(":%s is not a valid resolv.conf file\n", c.ResolvFile)
+			logger.Error("%s", err)
+			panic(err)
+		}
+		for _, server := range clientConfig.Servers {
+			nameserver := server + ":" + clientConfig.Port
+			r.servers = append(r.servers, nameserver)
+		}
+	}
+
+	return r
+}
+
+func (r *Resolver) ReadServerListFile(file string) {
+	buf, err := os.Open(file)
+	if err != nil {
+		panic("Can't open " + file)
+	}
+	scanner := bufio.NewScanner(buf)
+	for scanner.Scan() {
+		line := scanner.Text()
+		line = strings.TrimSpace(line)
+
+		if !strings.HasPrefix(line, "server") {
+			continue
+		}
+
+		sli := strings.Split(line, "=")
+		if len(sli) != 2 {
+			continue
+		}
+
+		line = strings.TrimSpace(sli[1])
+
+		tokens := strings.Split(line, "/")
+		switch len(tokens) {
+		case 3:
+			domain := tokens[1]
+			ip := tokens[2]
+			if !isDomain(domain) || !isIP(ip) {
+				continue
+			}
+			r.domain_server.sinsert(strings.Split(domain, "."), ip)
+		case 1:
+			srv_port := strings.Split(line, "#")
+			if len(srv_port) > 2 {
+				continue
+			}
+
+			ip := ""
+			if ip = srv_port[0]; !isIP(ip) {
+				continue
+			}
+
+			port := "53"
+			if len(srv_port) == 2 {
+				if _, err := strconv.Atoi(srv_port[1]); err != nil {
+					continue
+				}
+				port = srv_port[1]
+			}
+			r.servers = append(r.servers, ip+":"+port)
+
+		}
+	}
+
 }
 
 // Lookup will ask each nameserver in top-to-bottom fashion, starting a new request
@@ -60,7 +147,7 @@ func (r *Resolver) Lookup(net string, req *dns.Msg) (message *dns.Msg, err error
 				return
 			}
 		} else {
-			logger.Debug("%s resolv on %s (%s) ttl: %d", UnFqdn(qname), nameserver, net, rtt)
+			logger.Debug("%s resolv on %s (%s) ttl: %v", UnFqdn(qname), nameserver, net, rtt)
 		}
 		select {
 		case res <- r:
@@ -71,12 +158,14 @@ func (r *Resolver) Lookup(net string, req *dns.Msg) (message *dns.Msg, err error
 	ticker := time.NewTicker(time.Duration(settings.ResolvConfig.Interval) * time.Millisecond)
 	defer ticker.Stop()
 	// Start lookup on each nameserver top-down, in every second
-	for _, nameserver := range r.Nameservers() {
+	nameservers := r.Nameservers(qname)
+	for _, nameserver := range nameservers {
 		wg.Add(1)
 		go L(nameserver)
 		// but exit early, if we have an answer
 		select {
 		case r := <-res:
+			// logger.Debug("%s resolv on %s rtt: %v", UnFqdn(qname), nameserver, rtt)
 			return r, nil
 		case <-ticker.C:
 			continue
@@ -86,25 +175,32 @@ func (r *Resolver) Lookup(net string, req *dns.Msg) (message *dns.Msg, err error
 	wg.Wait()
 	select {
 	case r := <-res:
+		// logger.Debug("%s resolv on %s rtt: %v", UnFqdn(qname), nameserver, rtt)
 		return r, nil
 	default:
-		return nil, ResolvError{qname, net, r.Nameservers()}
+		return nil, ResolvError{qname, net, nameservers}
 	}
-
 }
 
 // Namservers return the array of nameservers, with port number appended.
 // '#' in the name is treated as port separator, as with dnsmasq.
-func (r *Resolver) Nameservers() (ns []string) {
-	for _, server := range r.config.Servers {
-		if i := strings.IndexByte(server, '#'); i > 0 {
-			server = net.JoinHostPort(server[:i], server[i+1:])
-		} else {
-			server = net.JoinHostPort(server, r.config.Port)
+
+func (r *Resolver) Nameservers(qname string) []string {
+	queryKeys := strings.Split(qname, ".")
+	queryKeys = queryKeys[:len(queryKeys)-1] // ignore last '.'
+
+	ns := []string{}
+	if v, found := r.domain_server.search(queryKeys); found {
+		logger.Debug("found upstream: %v", v)
+		server := v
+		nameserver := server + ":53"
+		ns = append(ns, nameserver)
 	}
-		ns = append(ns, server)
+
+	for _, nameserver := range r.servers {
+		ns = append(ns, nameserver)
 	}
-	return
+	return ns
 }
 
 func (r *Resolver) Timeout() time.Duration {

settings.go

@@ -34,10 +34,11 @@ type Settings struct {
 }
 
 type ResolvSettings struct {
-	ResolvFile string `toml:"resolv-file"`
 	Timeout        int
 	Interval       int
 	SetEDNS0       bool
+	ServerListFile string `toml:"server-list-file"`
+	ResolvFile     string `toml:"resolv-file"`
 }
 
 type DNSServerSettings struct {
@@ -93,7 +94,7 @@ func init() {
 
 	var configFile string
 
-	flag.StringVar(&configFile, "c", "godns.conf", "Look for godns toml-formatting config file in this directory")
+	flag.StringVar(&configFile, "c", "./etc/godns.conf", "Look for godns toml-formatting config file in this directory")
 	flag.Parse()
 
 	if _, err := toml.DecodeFile(configFile, &settings); err != nil {

sfx_tree.go

@@ -0,0 +1,65 @@
+package main
+
+type suffixTreeNode struct {
+	key      string
+	value    string
+	children map[string]*suffixTreeNode
+}
+
+func newSuffixTreeRoot() *suffixTreeNode {
+	return newSuffixTree("", "")
+}
+
+func newSuffixTree(key string, value string) *suffixTreeNode {
+	root := &suffixTreeNode{
+		key:      key,
+		value:    value,
+		children: map[string]*suffixTreeNode{},
+	}
+	return root
+}
+
+func (node *suffixTreeNode) ensureSubTree(key string) {
+	if _, ok := node.children[key]; !ok {
+		node.children[key] = newSuffixTree(key, "")
+	}
+}
+
+func (node *suffixTreeNode) insert(key string, value string) {
+	if c, ok := node.children[key]; ok {
+		c.value = value
+	} else {
+		node.children[key] = newSuffixTree(key, value)
+	}
+}
+
+func (node *suffixTreeNode) sinsert(keys []string, value string) {
+	if len(keys) == 0 {
+		return
+	}
+
+	key := keys[len(keys)-1]
+	if len(keys) > 1 {
+		node.ensureSubTree(key)
+		node.children[key].sinsert(keys[:len(keys)-1], value)
+		return
+	}
+
+	node.insert(key, value)
+}
+
+func (node *suffixTreeNode) search(keys []string) (string, bool) {
+	if len(keys) == 0 {
+		return "", false
+	}
+
+	key := keys[len(keys)-1]
+	if n, ok := node.children[key]; ok {
+		if nextValue, found := n.search(keys[:len(keys)-1]); found {
+			return nextValue, found
+		}
+		return n.value, (n.value != "")
+	}
+
+	return "", false
+}

sfx_tree_test.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"strings"
+	"testing"
+
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func Test_Suffix_Tree(t *testing.T) {
+	root := newSuffixTreeRoot()
+
+	Convey("Google should not be found", t, func() {
+		root.insert("cn", "114.114.114.114")
+		root.sinsert([]string{"baidu", "cn"}, "166.111.8.28")
+		root.sinsert([]string{"sina", "cn"}, "114.114.114.114")
+
+		v, found := root.search(strings.Split("google.com", "."))
+		So(found, ShouldEqual, false)
+
+		v, found = root.search(strings.Split("baidu.cn", "."))
+		So(found, ShouldEqual, true)
+		So(v, ShouldEqual, "166.111.8.28")
+	})
+
+	Convey("Google should be found", t, func() {
+		root.sinsert(strings.Split("com", "."), "")
+		root.sinsert(strings.Split("google.com", "."), "8.8.8.8")
+		root.sinsert(strings.Split("twitter.com", "."), "8.8.8.8")
+		root.sinsert(strings.Split("scholar.google.com", "."), "208.67.222.222")
+
+		v, found := root.search(strings.Split("google.com", "."))
+		So(found, ShouldEqual, true)
+		So(v, ShouldEqual, "8.8.8.8")
+
+		v, found = root.search(strings.Split("scholar.google.com", "."))
+		So(found, ShouldEqual, true)
+		So(v, ShouldEqual, "208.67.222.222")
+
+		v, found = root.search(strings.Split("twitter.com", "."))
+		So(found, ShouldEqual, true)
+		So(v, ShouldEqual, "8.8.8.8")
+
+		v, found = root.search(strings.Split("baidu.cn", "."))
+		So(found, ShouldEqual, true)
+		So(v, ShouldEqual, "166.111.8.28")
+	})
+
+}