Add HTTPS backend support

Signed-off-by: liangchuan <liangchuan@yf-networks.com>

Author: liangchuan

?bfe_balance/backend/health_check.go

@@ -17,25 +17,36 @@
 package backend
 
 import (
+	"crypto/x509"
+	"encoding/json"
 	"fmt"
 	"net"
 	"net/http"
+	"net/url"
+	"regexp"
+	"strconv"
 	"strings"
 	"time"
-)
 
-import (
 	"github.com/baidu/go-lib/log"
-)
 
-import (
 	"github.com/bfenetworks/bfe/bfe_config/bfe_cluster_conf/cluster_conf"
 	"github.com/bfenetworks/bfe/bfe_debug"
+	"github.com/bfenetworks/bfe/bfe_tls"
 )
 
+type checkRtn struct {
+	ok  bool
+	err error
+}
+
 func UpdateStatus(backend *BfeBackend, cluster string) bool {
+	var (
+		checkConf *cluster_conf.BackendCheck
+		httpConf *cluster_conf.BackendHTTPS
+	)
 	// get conf of health check, which is separately stored for each cluster
-	checkConf := getCheckConf(cluster)
+	checkConf, httpConf = getCheckConf(cluster)
 	if checkConf == nil {
 		// just ignore if not found health check conf
 		return false
@@ -45,14 +56,15 @@ func UpdateStatus(backend *BfeBackend, cluster string) bool {
 	// if backend's status become fail, start healthcheck.
 	// at most start 1 check goroutine for each backend.
 	if backend.UpdateStatus(*checkConf.FailNum) {
-		go check(backend, cluster)
+		go check(backend, cluster, httpConf)
 		return true
 	}
 
 	return false
 }
 
-func check(backend *BfeBackend, cluster string) {
+func check(backend *BfeBackend, cluster string, httpConf *cluster_conf.BackendHTTPS) {
+
 	log.Logger.Info("start healthcheck for %s", backend.Name)
 
 	// backend close chan
@@ -67,7 +79,7 @@ loop:
 		}
 
 		// get the latest conf to do health check
-		checkConf := getCheckConf(cluster)
+		checkConf, _ := getCheckConf(cluster)
 		if checkConf == nil {
 			// never come here
 			time.Sleep(time.Second)
@@ -76,7 +88,7 @@ loop:
 		checkInterval := time.Duration(*checkConf.CheckInterval) * time.Millisecond
 
 		// health check
-		if ok, err := CheckConnect(backend, checkConf); !ok {
+		if ok, err := CheckConnect(backend, checkConf, httpConf); !ok {
 			backend.ResetSuccNum()
 			if bfe_debug.DebugHealthCheck {
 				log.Logger.Debug("backend %s still not avail (check failure: %s)", backend.Name, err)
@@ -150,6 +162,232 @@ func doHTTPHealthCheck(request *http.Request, timeout time.Duration) (int, error
 	return response.StatusCode, nil
 }
 
+// extractIP extract ip address
+func extractIP(rsAddr string) string {
+	if strings.HasPrefix(rsAddr, "[") {
+		// IPv6
+		endIndex := strings.LastIndex(rsAddr, "]")
+		if endIndex == -1 {
+			return ""
+		}
+		ip := rsAddr[:endIndex+1]
+		if net.ParseIP(ip[1:endIndex]) == nil {
+			return ""
+		}
+		return ip
+	} else {
+		// IPv4
+		ip := strings.Split(rsAddr, ":")[0]
+		if net.ParseIP(ip) == nil {
+			return ""
+		}
+		return ip
+	}
+}
+
+func getHostByType(host, rsAddr, hostType *string, def string) string {
+	if hostType == nil {
+		ht := cluster_conf.HostType_HOST
+		hostType = &ht
+	}
+	switch *hostType {
+	case cluster_conf.HostType_Instance_IP:
+		if rsAddr != nil {
+			return extractIP(*rsAddr)
+		}
+	default:
+		if host != nil {
+			return *host
+		}
+	}
+	return def
+}
+
+// add by liangc
+func checkHTTPSConnect(backend *BfeBackend, checkConf *cluster_conf.BackendCheck, httpConf *cluster_conf.BackendHTTPS) (bool, error) {
+	var (
+		err          error
+		conn         net.Conn
+		addrInfo     = getHealthCheckAddrInfo(backend, checkConf)
+		checkTimeout = 30 * time.Second
+		statusCode   = 0
+		host         string
+		rootCAs      *x509.CertPool        = nil
+		certs        []bfe_tls.Certificate = nil
+		cert         bfe_tls.Certificate
+		insecure     = false
+		uri          = "/"
+		checkRtnCh   = make(chan checkRtn, 1)
+		rtn          checkRtn
+	)
+
+	var (
+		getStatusCodeFn = func(statusLine string) (int, error) {
+			// "HTTP/1.1 200 OK"
+			re, err := regexp.Compile(`\s(\d{3})\s`)
+			if err != nil {
+				return 0, err
+			}
+			matches := re.FindStringSubmatch(statusLine)
+			if len(matches) == 2 {
+				statusCode := matches[1]
+				log.Logger.Debug("StatusCode = %s, raw = %s", statusCode, statusLine)
+				return strconv.Atoi(statusCode)
+			} else {
+				return 0, fmt.Errorf("Status code not found: %s", statusLine)
+			}
+		}
+
+		doCheckFn = func(conn net.Conn) checkRtn {
+			// TLS Check >>>>>>>
+			if err = conn.(*bfe_tls.Conn).Handshake(); err != nil {
+				log.Logger.Debug("debug_http err=%s", err.Error())
+				return checkRtn{false, err}
+			}
+			if *checkConf.Schem == "tls" { // http or tls
+				return checkRtn{true, nil}
+			}
+			// TLS Check <<<<<<<
+
+			// HTTPS Check vvvvvvvvvvvvv
+			if checkConf.Uri != nil && *checkConf.Uri != "" {
+				uri = *checkConf.Uri
+			}
+			request := fmt.Sprintf("GET %s HTTP/1.1\r\n"+
+				"Host: %s\r\n"+
+				"User-Agent: BFE-Health-Check\r\n"+
+				"\r\n", uri, host)
+			_, err = conn.Write([]byte(request))
+			if err != nil {
+				log.Logger.Debug("debug_http err=%s", err.Error())
+				return checkRtn{false, err}
+			}
+			var (
+				response = ""
+				ok       bool
+				err      error
+				data     = make([]byte, 0)
+				bufSz    = 128
+				buf      = make([]byte, bufSz)
+				total    = 0
+			)
+			//TODO: if timeout , how to handle ?
+			for {
+				total, err = conn.Read(buf)
+				if err != nil {
+					break
+				}
+				data = append(data, buf[:total]...)
+				if total < bufSz {
+					break
+				}
+			}
+			//data, err = ioutil.ReadAll(conn)
+			if err != nil {
+				log.Logger.Debug("debug_http err=%s", err.Error())
+				return checkRtn{false, err}
+			}
+			response = string(data)
+			log.Logger.Debug("<- Request:\n%s", request)
+			log.Logger.Debug("-> Response:\n%s", response)
+			if checkConf.StatusCode != nil { // check status code
+				var (
+					s   string
+					arr = strings.Split(response, "\n")
+				)
+				if len(arr) > 0 {
+					s = strings.ToUpper(arr[0])
+					statusCode, err = getStatusCodeFn(s)
+					if err != nil {
+						return checkRtn{false, err}
+					}
+					if checkConf.StatusCodeRange != nil && *checkConf.StatusCodeRange != "" {
+						log.Logger.Debug("statusCode=%d, statusCodeRange=%s", statusCode, *checkConf.StatusCodeRange)
+						ok, err := cluster_conf.MatchStatusCodeRange(fmt.Sprintf("%d", statusCode), *checkConf.StatusCodeRange)
+						return checkRtn{ok, err}
+					}
+				}
+				ok, err = cluster_conf.MatchStatusCode(statusCode, *checkConf.StatusCode)
+			}
+			return checkRtn{ok, err}
+		}
+
+		toStringFn = func(o interface{}) string {
+			b, err := json.Marshal(o)
+			if err != nil {
+				return err.Error()
+			}
+			return string(b)
+		}
+	)
+
+	if checkConf.CheckTimeout != nil {
+		checkTimeout = time.Duration(*checkConf.CheckTimeout) * time.Millisecond
+	}
+	conn, err = net.DialTimeout("tcp", addrInfo, checkTimeout)
+
+	if err != nil {
+		log.Logger.Debug("debug_http err=%v", err)
+		return false, err
+	}
+
+	defer func() {
+		if r := recover(); r != nil {
+			log.Logger.Debug("recover_panic = %v", r)
+		}
+		_ = conn.Close()
+	}()
+
+	_, err = url.Parse(fmt.Sprintf("%s://%s%s", "http", addrInfo, *checkConf.Uri))
+	if err != nil {
+		log.Logger.Debug("debug_http err=%v", err)
+		return false, err
+	}
+
+	serverName := ""
+	if httpConf.RSHost != nil {
+		serverName = *httpConf.RSHost
+	} else if checkConf.Host != nil {
+		serverName = *checkConf.Host
+	}
+	host = getHostByType(checkConf.Host, &addrInfo, checkConf.HostType, serverName)
+
+	rootCAs, err = httpConf.GetRSCAList()
+
+	if cert, err = httpConf.GetBFECert(); err == nil {
+		certs = []bfe_tls.Certificate{cert}
+	}
+
+	if httpConf.RSInsecureSkipVerify != nil {
+		insecure = *httpConf.RSInsecureSkipVerify
+	}
+
+	conn = bfe_tls.Client(conn, &bfe_tls.Config{
+		Certificates:          certs,
+		InsecureSkipVerify:    true,
+		ServerName:            host,
+		RootCAs:               rootCAs,
+		VerifyPeerCertificate: bfe_tls.NewVerifyPeerCertHooks(insecure, host, rootCAs).Ready(),
+	})
+
+	log.Logger.Debug("httpCheck conf=%s", toStringFn(checkConf))
+	go func(conn net.Conn, rtnCh chan checkRtn) {
+		rtnCh <- doCheckFn(conn)
+	}(conn, checkRtnCh)
+
+	if checkTimeout > 0 {
+		select {
+		case rtn = <-checkRtnCh:
+			return rtn.ok, rtn.err
+		case <-time.Tick(checkTimeout):
+			return false, fmt.Errorf("http checkTimeout %dms", checkTimeout/time.Millisecond)
+		}
+	} else {
+		rtn = <-checkRtnCh
+	}
+	return rtn.ok, rtn.err
+}
+
 func checkHTTPConnect(backend *BfeBackend, checkConf *cluster_conf.BackendCheck) (bool, error) {
 	// prepare health check request
 	addrInfo := getHealthCheckAddrInfo(backend, checkConf)
@@ -182,26 +420,28 @@ func checkHTTPConnect(backend *BfeBackend, checkConf *cluster_conf.BackendCheck)
 }
 
 // CheckConnect checks whether backend server become available.
-func CheckConnect(backend *BfeBackend, checkConf *cluster_conf.BackendCheck) (bool, error) {
+func CheckConnect(backend *BfeBackend, checkConf *cluster_conf.BackendCheck, httpConf *cluster_conf.BackendHTTPS) (bool, error) {
 	switch *checkConf.Schem {
 	case "http":
 		return checkHTTPConnect(backend, checkConf)
 	case "tcp":
 		return checkTCPConnect(backend, checkConf)
+	case "http", "tls":
+		return checkHTTPSConnect(backend, checkConf, httpConf)
 	default:
 		// never come here
 		return checkHTTPConnect(backend, checkConf)
 	}
 }
 
 // CheckConfFetcher returns current health check conf for cluster.
-type CheckConfFetcher func(cluster string) *cluster_conf.BackendCheck
+type CheckConfFetcher func(name string) (*cluster_conf.BackendCheck, *cluster_conf.BackendHTTPS)
 
 var checkConfFetcher CheckConfFetcher
 
-func getCheckConf(cluster string) *cluster_conf.BackendCheck {
+func getCheckConf(cluster string) (*cluster_conf.BackendCheck, *cluster_conf.BackendHTTPS) {
 	if checkConfFetcher == nil {
-		return nil
+		return nil, nil
 	}
 	return checkConfFetcher(cluster)
 }