Fixes for vl3_dns

pkg/networkservice/connectioncontext/dnscontext/server.go

@@ -27,6 +27,7 @@ import (
 	"github.com/networkservicemesh/api/pkg/api/networkservice"
 
 	"github.com/networkservicemesh/sdk/pkg/networkservice/core/next"
+	"github.com/networkservicemesh/sdk/pkg/tools/dnsutils"
 )
 
 // GetDNSConfigsFunc gets dns configs
@@ -47,7 +48,7 @@ func (d *dnsContextServer) Request(ctx context.Context, request *networkservice.
 	}
 
 	for _, config := range d.configs {
-		if !contains(request.GetConnection().GetContext().GetDnsContext().Configs, config) {
+		if !dnsutils.ContainsDNSConfig(request.GetConnection().GetContext().GetDnsContext().Configs, config) {
 			request.GetConnection().GetContext().GetDnsContext().Configs = append(request.GetConnection().GetContext().GetDnsContext().Configs, config)
 		}
 	}
@@ -57,34 +58,3 @@ func (d *dnsContextServer) Request(ctx context.Context, request *networkservice.
 func (d *dnsContextServer) Close(ctx context.Context, conn *networkservice.Connection) (*empty.Empty, error) {
 	return next.Server(ctx).Close(ctx, conn)
 }
-
-func contains(array []*networkservice.DNSConfig, value *networkservice.DNSConfig) bool {
-	for i := range array {
-		if equal(array[i].DnsServerIps, value.DnsServerIps) && equal(array[i].SearchDomains, value.SearchDomains) {
-			return true
-		}
-	}
-	return false
-}
-
-func equal(a, b []string) bool {
-	if len(a) != len(b) {
-		return false
-	}
-
-	diff := make(map[string]int, len(a))
-	for _, v := range a {
-		diff[v]++
-	}
-
-	for _, v := range b {
-		if _, ok := diff[v]; !ok {
-			return false
-		}
-		diff[v]--
-		if diff[v] == 0 {
-			delete(diff, v)
-		}
-	}
-	return len(diff) == 0
-}

pkg/networkservice/connectioncontext/dnscontext/vl3dns/server.go

@@ -89,24 +89,15 @@ func (n *vl3DNSServer) Request(ctx context.Context, request *networkservice.Netw
 		request.Connection.Context.DnsContext = new(networkservice.DNSContext)
 	}
 
-	var dnsContext = request.GetConnection().GetContext().GetDnsContext()
-	var clientsConfigs = dnsContext.GetConfigs()
-
-	dnsContext.Configs = append(dnsContext.Configs, &networkservice.DNSConfig{
-		DnsServerIps: []string{n.getDNSServerIP().String()},
-	})
+	var clientsConfigs = request.GetConnection().GetContext().GetDnsContext().GetConfigs()
 
+	dnsServerIPStr, added := n.addDNSContext(request.GetConnection())
 	var recordNames, err = n.buildSrcDNSRecords(request.GetConnection())
 
 	if err != nil {
 		return nil, err
 	}
 
-	var ips []net.IP
-	for _, srcIPNet := range request.GetConnection().GetContext().GetIpContext().GetSrcIPNets() {
-		ips = append(ips, srcIPNet.IP)
-	}
-
 	if v, ok := metadata.Map(ctx, false).LoadAndDelete(clientDNSNameKey{}); ok {
 		var previousNames = v.([]string)
 		if !compareStringSlices(previousNames, recordNames) {
@@ -115,6 +106,8 @@ func (n *vl3DNSServer) Request(ctx context.Context, request *networkservice.Netw
 			}
 		}
 	}
+
+	ips := getSrcIPs(request.GetConnection())
 	if len(ips) > 0 {
 		for _, recordName := range recordNames {
 			n.dnsServerRecords.Store(recordName, ips)
@@ -127,11 +120,11 @@ func (n *vl3DNSServer) Request(ctx context.Context, request *networkservice.Netw
 
 	if err == nil {
 		configs := make([]*networkservice.DNSConfig, 0)
-		if srcRoutes := resp.GetContext().GetIpContext().GetSrcIPRoutes(); len(srcRoutes) > 0 {
+		if srcRoutes := resp.GetContext().GetIpContext().GetSrcRoutes(); len(srcRoutes) > 0 {
 			var lastPrefix = srcRoutes[len(srcRoutes)-1].Prefix
 			for _, config := range clientsConfigs {
 				for _, serverIP := range config.DnsServerIps {
-					if serverIP == n.getDNSServerIP().String() {
+					if added && dnsServerIPStr == serverIP {
 						continue
 					}
 					if withinPrefix(serverIP, lastPrefix) {
@@ -158,6 +151,20 @@ func (n *vl3DNSServer) Close(ctx context.Context, conn *networkservice.Connectio
 	return next.Server(ctx).Close(ctx, conn)
 }
 
+func (n *vl3DNSServer) addDNSContext(c *networkservice.Connection) (added string, ok bool) {
+	if dnsServerIP := n.getDNSServerIP(); dnsServerIP != nil {
+		var dnsContext = c.GetContext().GetDnsContext()
+		configToAdd := &networkservice.DNSConfig{
+			DnsServerIps: []string{dnsServerIP.String()},
+		}
+		if !dnsutils.ContainsDNSConfig(dnsContext.Configs, configToAdd) {
+			dnsContext.Configs = append(dnsContext.Configs, configToAdd)
+		}
+		return dnsServerIP.String(), true
+	}
+	return "", false
+}
+
 func (n *vl3DNSServer) buildSrcDNSRecords(c *networkservice.Connection) ([]string, error) {
 	var result []string
 	for _, templ := range n.domainSchemeTemplates {
@@ -190,3 +197,11 @@ func withinPrefix(ipAddr, prefix string) bool {
 	var pool = ippool.NewWithNet(ipNet)
 	return pool.ContainsString(ipAddr)
 }
+
+func getSrcIPs(c *networkservice.Connection) []net.IP {
+	var ips []net.IP
+	for _, srcIPNet := range c.GetContext().GetIpContext().GetSrcIPNets() {
+		ips = append(ips, srcIPNet.IP)
+	}
+	return ips
+}

pkg/tools/dnsutils/dnsutils.go

@@ -23,6 +23,8 @@ import (
 
 	"github.com/miekg/dns"
 
+	"github.com/networkservicemesh/api/pkg/api/networkservice"
+
 	"github.com/networkservicemesh/sdk/pkg/tools/log"
 )
 
@@ -56,3 +58,35 @@ func ListenAndServe(ctx context.Context, handler Handler, listenOn string) {
 		}()
 	}
 }
+
+// ContainsDNSConfig returns true if array contains a specific dns config
+func ContainsDNSConfig(array []*networkservice.DNSConfig, value *networkservice.DNSConfig) bool {
+	for i := range array {
+		if equal(array[i].DnsServerIps, value.DnsServerIps) && equal(array[i].SearchDomains, value.SearchDomains) {
+			return true
+		}
+	}
+	return false
+}
+
+func equal(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+
+	diff := make(map[string]int, len(a))
+	for _, v := range a {
+		diff[v]++
+	}
+
+	for _, v := range b {
+		if _, ok := diff[v]; !ok {
+			return false
+		}
+		diff[v]--
+		if diff[v] == 0 {
+			delete(diff, v)
+		}
+	}
+	return len(diff) == 0
+}