支持任意域名通过CNAME访问服务（开启选项后）

go.mod

@@ -22,6 +22,7 @@ require (
 	github.com/jsummers/gobmp v0.0.0-20151104160322-e2ba15ffa76e // indirect
 	github.com/lionsoul2014/ip2region v2.2.0-release+incompatible
 	github.com/mattn/go-sqlite3 v2.0.3+incompatible
+	github.com/miekg/dns v1.1.43
 	github.com/mssola/user_agent v0.5.2
 	github.com/pires/go-proxyproto v0.6.1
 	github.com/shirou/gopsutil v3.21.5+incompatible

go.sum

@@ -96,6 +96,8 @@ github.com/lionsoul2014/ip2region v2.2.0-release+incompatible h1:1qp9iks+69h7IGL
 github.com/lionsoul2014/ip2region v2.2.0-release+incompatible/go.mod h1:+ZBN7PBoh5gG6/y0ZQ85vJDBe21WnfbRrQQwTfliJJI=
 github.com/mattn/go-sqlite3 v2.0.3+incompatible h1:gXHsfypPkaMZrKbD5209QV9jbUTJKjyR5WD3HYQSd+U=
 github.com/mattn/go-sqlite3 v2.0.3+incompatible/go.mod h1:FPy6KqzDD04eiIsT53CuJW3U88zkxoIYsOqkbpncsNc=
+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/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/mssola/user_agent v0.5.2 h1:CZkTUahjL1+OcZ5zv3kZr8QiJ8jy2H08vZIEkBeRbxo=
@@ -163,6 +165,7 @@ golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAG
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+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 v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

internal/nodes/listener_base.go

@@ -21,19 +21,19 @@ type BaseListener struct {
 	countActiveConnections int64 // 当前活跃的连接数
 }
 
-// 初始化
+// Init 初始化
 func (this *BaseListener) Init() {
 	this.namedServers = map[string]*NamedServer{}
 }
 
-// 清除既有配置
+// Reset 清除既有配置
 func (this *BaseListener) Reset() {
 	this.namedServersLocker.Lock()
 	this.namedServers = map[string]*NamedServer{}
 	this.namedServersLocker.Unlock()
 }
 
-// 获取当前活跃连接数
+// CountActiveListeners 获取当前活跃连接数
 func (this *BaseListener) CountActiveListeners() int {
 	return types.Int(this.countActiveConnections)
 }
@@ -253,3 +253,38 @@ func (this *BaseListener) findNamedServerMatched(name string) (serverConfig *ser
 
 	return nil, name
 }
+
+// 使用CNAME来查找服务
+// TODO 防止单IP随机生成域名攻击
+func (this *BaseListener) findServerWithCname(domain string) *serverconfigs.ServerConfig {
+	if !sharedNodeConfig.SupportCNAME {
+		return nil
+	}
+
+	var realName = sharedCNAMEManager.Lookup(domain)
+	if len(realName) == 0 {
+		return nil
+	}
+
+	this.serversLocker.Lock()
+	defer this.serversLocker.Unlock()
+
+	group := this.Group
+	if group == nil {
+		return nil
+	}
+
+	currentServers := group.Servers
+	countServers := len(currentServers)
+	if countServers == 0 {
+		return nil
+	}
+
+	for _, server := range currentServers {
+		if server.SupportCNAME && lists.ContainsString(server.AliasServerNames, realName) {
+			return server
+		}
+	}
+
+	return nil
+}

internal/nodes/listener_http.go

@@ -156,6 +156,8 @@ func (this *HTTPListener) handleHTTP(rawWriter http.ResponseWriter, rawReq *http
 	}
 
 	server, serverName := this.findNamedServer(domain)
+	if server == nil {
+		server = this.findServerWithCname(domain)
 		if server == nil {
 			// 严格匹配域名模式下，我们拒绝用户访问
 			if sharedNodeConfig.GlobalConfig != nil && sharedNodeConfig.GlobalConfig.HTTPAll.MatchDomainStrictly {
@@ -184,6 +186,9 @@ func (this *HTTPListener) handleHTTP(rawWriter http.ResponseWriter, rawReq *http
 
 			http.Error(rawWriter, "404 page not found: '"+rawReq.URL.String()+"'", http.StatusNotFound)
 			return
+		} else {
+			serverName = domain
+		}
 	}
 
 	// 包装新请求对象

internal/nodes/server_cname_manager.go

@@ -0,0 +1,48 @@
+// Copyright 2021 Liuxiangchao iwind.liu@gmail.com. All rights reserved.
+
+package nodes
+
+import (
+	"github.com/TeaOSLab/EdgeNode/internal/ttlcache"
+	"github.com/TeaOSLab/EdgeNode/internal/utils"
+	"github.com/iwind/TeaGo/types"
+	"strings"
+	"sync"
+	"time"
+)
+
+var sharedCNAMEManager = NewServerCNAMEManager()
+
+// ServerCNAMEManager 服务CNAME管理
+// TODO 需要自动更新缓存里的记录
+type ServerCNAMEManager struct {
+	ttlCache *ttlcache.Cache
+
+	locker sync.Mutex
+}
+
+func NewServerCNAMEManager() *ServerCNAMEManager {
+	return &ServerCNAMEManager{
+		ttlCache: ttlcache.NewCache(),
+	}
+}
+
+func (this *ServerCNAMEManager) Lookup(domain string) string {
+	if len(domain) == 0 {
+		return ""
+	}
+
+	var item = this.ttlCache.Read(domain)
+	if item != nil {
+		return types.String(item.Value)
+	}
+
+	cname, _ := utils.LookupCNAME(domain)
+	if len(cname) > 0 {
+		cname = strings.TrimSuffix(cname, ".")
+	}
+
+	this.ttlCache.Write(domain, cname, time.Now().Unix()+600)
+
+	return cname
+}

internal/nodes/server_cname_manager_test.go

@@ -0,0 +1,19 @@
+// Copyright 2021 Liuxiangchao iwind.liu@gmail.com. All rights reserved.
+
+package nodes
+
+import (
+	"testing"
+	"time"
+)
+
+func TestServerCNameManager_Lookup(t *testing.T) {
+	var cnameManager = NewServerCNAMEManager()
+	t.Log(cnameManager.Lookup("www.yun4s.cn"))
+
+	var before = time.Now()
+	defer func() {
+		t.Log(time.Since(before).Seconds()*1000, "ms")
+	}()
+	t.Log(cnameManager.Lookup("www.yun4s.cn"))
+}

internal/utils/lookup.go

@@ -0,0 +1,35 @@
+package utils
+
+import (
+	"github.com/TeaOSLab/EdgeCommon/pkg/configutils"
+	"github.com/miekg/dns"
+)
+
+// LookupCNAME 获取CNAME
+func LookupCNAME(host string) (string, error) {
+	config, err := dns.ClientConfigFromFile("/etc/resolv.conf")
+	if err != nil {
+		return "", err
+	}
+
+	c := new(dns.Client)
+	m := new(dns.Msg)
+
+	m.SetQuestion(host+".", dns.TypeCNAME)
+	m.RecursionDesired = true
+
+	var lastErr error
+	for _, serverAddr := range config.Servers {
+		r, _, err := c.Exchange(m, configutils.QuoteIP(serverAddr)+":"+config.Port)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		if len(r.Answer) == 0 {
+			continue
+		}
+
+		return r.Answer[0].(*dns.CNAME).Target, nil
+	}
+	return "", lastErr
+}

internal/utils/lookup_test.go

@@ -0,0 +1,9 @@
+// Copyright 2021 Liuxiangchao iwind.liu@gmail.com. All rights reserved.
+
+package utils
+
+import "testing"
+
+func TestLookupCNAME(t *testing.T) {
+	t.Log(LookupCNAME("www.yun4s.cn"))
+}