dns: 支持反解

pkg/dns/dns.go

@@ -32,6 +32,9 @@ import (
 
 const (
 	PluginName string = "yunion"
+
+	// defaultTTL to apply to all answers
+	defaultTTL = 10
 )
 
 var (
@@ -52,6 +55,7 @@ type SRegionDNS struct {
 	Next          plugin.Handler
 	Fall          fall.F
 	Zones         []string
+	PrimaryZone   string
 	Upstream      upstream.Upstream
 	SqlConnection string
 	K8sConfigFile string
@@ -234,11 +238,6 @@ func (r *SRegionDNS) Services(state request.Request, exact bool, opt plugin.Opti
 	return internal, e
 }
 
-// Reverse implements the ServiceBackend interface
-func (r *SRegionDNS) Reverse(state request.Request, exact bool, opt plugin.Options) (services []msg.Service, err error) {
-	return r.Services(state, exact, opt)
-}
-
 // Lookup implements the ServiceBackend interface
 func (r *SRegionDNS) Lookup(state request.Request, name string, typ uint16) (*dns.Msg, error) {
 	return r.Upstream.Lookup(state, name, typ)
@@ -398,7 +397,7 @@ func (r *SRegionDNS) findInternalRecordIps(req *recordRequest) ([]string, error)
 func ips2DnsRecords(ips []string) []msg.Service {
 	recs := make([]msg.Service, 0)
 	for _, ip := range ips {
-		s := msg.Service{Host: ip, TTL: 5 * 60}
+		s := msg.Service{Host: ip, TTL: defaultTTL}
 		recs = append(recs, s)
 	}
 	return recs

pkg/dns/reverse.go

@@ -0,0 +1,61 @@
+package dns
+
+import (
+	"strings"
+
+	"github.com/coredns/coredns/plugin"
+	"github.com/coredns/coredns/plugin/etcd/msg"
+	"github.com/coredns/coredns/plugin/pkg/dnsutil"
+	"github.com/coredns/coredns/request"
+
+	"github.com/yunionio/log"
+
+	"github.com/yunionio/onecloud/pkg/compute/models"
+)
+
+// Reverse implements the ServiceBackend interface
+func (r *SRegionDNS) Reverse(state request.Request, exact bool, opt plugin.Options) (services []msg.Service, err error) {
+	ip := dnsutil.ExtractAddressFromReverse(state.Name())
+	if ip == "" {
+		_, e := r.Records(state, exact)
+		return nil, e
+	}
+	records, err := r.getNameForIp(ip, state)
+	if err != nil {
+		log.Errorf("Reverse get name for ip: %v", err)
+	}
+	if len(records) == 0 {
+		return records, errNoItems
+	}
+	return records, nil
+}
+
+func (r *SRegionDNS) getNameForIp(ip string, state request.Request) ([]msg.Service, error) {
+	req, e := parseRequest(state)
+	if e != nil {
+		return nil, e
+	}
+
+	// 1. try local dns records table
+	records := models.DnsRecordManager.QueryDnsIps(req.ProjectId(), req.Name(), req.Type())
+	for _, rec := range records {
+		return []msg.Service{{Host: rec.Addr, TTL: uint32(rec.Ttl)}}, nil
+	}
+
+	// 2. try hosts table
+	host := models.HostnetworkManager.GetHostByAddress(ip)
+	if host != nil {
+		return []msg.Service{{Host: r.joinDomain(host.Name), TTL: defaultTTL}}, nil
+	}
+
+	// 3. try guests table
+	guest := models.GuestnetworkManager.GetGuestByAddress(ip)
+	if guest != nil {
+		return []msg.Service{{Host: r.joinDomain(guest.Name), TTL: defaultTTL}}, nil
+	}
+	return nil, errNoItems
+}
+
+func (r *SRegionDNS) joinDomain(name string) string {
+	return strings.Join([]string{name, r.PrimaryZone}, ".")
+}

pkg/dns/setup.go

@@ -1,12 +1,15 @@
 package dns
 
 import (
+	"fmt"
 	"os"
 
 	"github.com/coredns/coredns/core/dnsserver"
 	"github.com/coredns/coredns/plugin"
 	"github.com/coredns/coredns/plugin/pkg/upstream"
 	"github.com/mholt/caddy"
+
+	"github.com/yunionio/pkg/util/regutils"
 )
 
 func init() {
@@ -24,6 +27,13 @@ func setup(c *caddy.Controller) error {
 		return plugin.Error(PluginName, err)
 	}
 
+	if rDNS.PrimaryZone == "" {
+		return fmt.Errorf("dns_domain must provided")
+	}
+	if !regutils.MatchDomainName(rDNS.PrimaryZone) {
+		return fmt.Errorf("dns_domain %q not match domain format", rDNS.PrimaryZone)
+	}
+
 	err = rDNS.initDB(c)
 	if err != nil {
 		return plugin.Error(PluginName, err)
@@ -58,6 +68,11 @@ func parseConfig(c *caddy.Controller) (*SRegionDNS, error) {
 		if c.NextBlock() {
 			for {
 				switch c.Val() {
+				case "dns_domain":
+					if !c.NextArg() {
+						return nil, c.ArgErr()
+					}
+					rDNS.PrimaryZone = c.Val()
 				case "fallthrough":
 					rDNS.Fall.SetZonesFromArgs(c.RemainingArgs())
 				case "sql_connection":