LDAP Provider: TLS support (#1137)

Dockerfile

@@ -51,6 +51,7 @@ COPY --from=website-builder /static/build_docs/ /work/website/build_docs/
 
 COPY ./cmd /work/cmd
 COPY ./web/static.go /work/web/static.go
+COPY ./website/static.go /work/website/static.go
 COPY ./internal /work/internal
 COPY ./go.mod /work/go.mod
 COPY ./go.sum /work/go.sum

authentik/core/api/groups.py

@@ -1,24 +1,60 @@
 """Groups API Viewset"""
 from django.db.models.query import QuerySet
-from rest_framework.fields import JSONField
-from rest_framework.serializers import ModelSerializer
+from rest_framework.fields import BooleanField, CharField, JSONField
+from rest_framework.serializers import ListSerializer, ModelSerializer
 from rest_framework.viewsets import ModelViewSet
 from rest_framework_guardian.filters import ObjectPermissionsFilter
 
 from authentik.core.api.used_by import UsedByMixin
 from authentik.core.api.utils import is_dict
-from authentik.core.models import Group
+from authentik.core.models import Group, User
+
+
+class GroupMemberSerializer(ModelSerializer):
+    """Stripped down user serializer to show relevant users for groups"""
+
+    is_superuser = BooleanField(read_only=True)
+    avatar = CharField(read_only=True)
+    attributes = JSONField(validators=[is_dict], required=False)
+    uid = CharField(read_only=True)
+
+    class Meta:
+
+        model = User
+        fields = [
+            "pk",
+            "username",
+            "name",
+            "is_active",
+            "last_login",
+            "is_superuser",
+            "email",
+            "avatar",
+            "attributes",
+            "uid",
+        ]
 
 
 class GroupSerializer(ModelSerializer):
     """Group Serializer"""
 
     attributes = JSONField(validators=[is_dict], required=False)
+    users_obj = ListSerializer(
+        child=GroupMemberSerializer(), read_only=True, source="users", required=False
+    )
 
     class Meta:
 
         model = Group
-        fields = ["pk", "name", "is_superuser", "parent", "users", "attributes"]
+        fields = [
+            "pk",
+            "name",
+            "is_superuser",
+            "parent",
+            "users",
+            "attributes",
+            "users_obj",
+        ]
 
 
 class GroupViewSet(UsedByMixin, ModelViewSet):

authentik/providers/ldap/api.py

@@ -17,6 +17,8 @@ class LDAPProviderSerializer(ProviderSerializer):
         fields = ProviderSerializer.Meta.fields + [
             "base_dn",
             "search_group",
+            "certificate",
+            "tls_server_name",
         ]
 
 
@@ -44,6 +46,8 @@ class LDAPOutpostConfigSerializer(ModelSerializer):
             "bind_flow_slug",
             "application_slug",
             "search_group",
+            "certificate",
+            "tls_server_name",
         ]
 
 

authentik/providers/ldap/controllers/docker.py

@@ -11,4 +11,5 @@ class LDAPDockerController(DockerController):
         super().__init__(outpost, connection)
         self.deployment_ports = [
             DeploymentPort(389, "ldap", "tcp", 3389),
+            DeploymentPort(636, "ldaps", "tcp", 6636),
         ]

authentik/providers/ldap/controllers/kubernetes.py

@@ -11,4 +11,5 @@ class LDAPKubernetesController(KubernetesController):
         super().__init__(outpost, connection)
         self.deployment_ports = [
             DeploymentPort(389, "ldap", "tcp", 3389),
+            DeploymentPort(636, "ldaps", "tcp", 6636),
         ]

authentik/providers/ldap/migrations/0003_auto_20210713_1138.py

@@ -0,0 +1,30 @@
+# Generated by Django 3.2.5 on 2021-07-13 11:38
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("authentik_crypto", "0002_create_self_signed_kp"),
+        ("authentik_providers_ldap", "0002_ldapprovider_search_group"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="ldapprovider",
+            name="certificate",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                to="authentik_crypto.certificatekeypair",
+            ),
+        ),
+        migrations.AddField(
+            model_name="ldapprovider",
+            name="tls_server_name",
+            field=models.TextField(blank=True, default=""),
+        ),
+    ]

authentik/providers/ldap/models.py

@@ -6,6 +6,7 @@ from django.utils.translation import gettext_lazy as _
 from rest_framework.serializers import Serializer
 
 from authentik.core.models import Group, Provider
+from authentik.crypto.models import CertificateKeyPair
 from authentik.outposts.models import OutpostModel
 
 
@@ -28,6 +29,17 @@ class LDAPProvider(OutpostModel, Provider):
         ),
     )
 
+    tls_server_name = models.TextField(
+        default="",
+        blank=True,
+    )
+    certificate = models.ForeignKey(
+        CertificateKeyPair,
+        on_delete=models.SET_NULL,
+        null=True,
+        blank=True,
+    )
+
     @property
     def launch_url(self) -> Optional[str]:
         """LDAP never has a launch URL"""

outpost/pkg/ak/cert.go

@@ -37,7 +37,7 @@ func GenerateSelfSignedCert() (tls.Certificate, error) {
 		SerialNumber: serialNumber,
 		Subject: pkix.Name{
 			Organization: []string{"authentik"},
-			CommonName:   "authentik Proxy default certificate",
+			CommonName:   "authentik Outpost default certificate",
 		},
 		NotBefore: notBefore,
 		NotAfter:  notAfter,

outpost/pkg/ak/global.go

@@ -1,6 +1,8 @@
 package ak
 
 import (
+	"context"
+	"crypto/tls"
 	"net/http"
 	"os"
 	"strings"
@@ -9,6 +11,7 @@ import (
 	"github.com/getsentry/sentry-go"
 	httptransport "github.com/go-openapi/runtime/client"
 	log "github.com/sirupsen/logrus"
+	"goauthentik.io/outpost/api"
 	"goauthentik.io/outpost/pkg"
 )
 
@@ -66,3 +69,21 @@ func GetTLSTransport() http.RoundTripper {
 	}
 	return tlsTransport
 }
+
+// ParseCertificate Load certificate from Keyepair UUID and parse it into a go Certificate
+func ParseCertificate(kpUuid string, cryptoApi *api.CryptoApiService) (*tls.Certificate, error) {
+	cert, _, err := cryptoApi.CryptoCertificatekeypairsViewCertificateRetrieve(context.Background(), kpUuid).Execute()
+	if err != nil {
+		return nil, err
+	}
+	key, _, err := cryptoApi.CryptoCertificatekeypairsViewPrivateKeyRetrieve(context.Background(), kpUuid).Execute()
+	if err != nil {
+		return nil, err
+	}
+
+	x509cert, err := tls.X509KeyPair([]byte(cert.Data), []byte(key.Data))
+	if err != nil {
+		return nil, err
+	}
+	return &x509cert, nil
+}

outpost/pkg/ldap/api.go

@@ -2,6 +2,7 @@ package ldap
 
 import (
 	"context"
+	"crypto/tls"
 	"errors"
 	"fmt"
 	"net/http"
@@ -10,6 +11,7 @@ import (
 
 	"github.com/go-openapi/strfmt"
 	log "github.com/sirupsen/logrus"
+	"goauthentik.io/outpost/pkg/ak"
 )
 
 func (ls *LDAPServer) Refresh() error {
@@ -24,6 +26,7 @@ func (ls *LDAPServer) Refresh() error {
 	for idx, provider := range outposts.Results {
 		userDN := strings.ToLower(fmt.Sprintf("ou=users,%s", *provider.BaseDn))
 		groupDN := strings.ToLower(fmt.Sprintf("ou=groups,%s", *provider.BaseDn))
+		logger := log.WithField("logger", "authentik.outpost.ldap").WithField("provider", provider.Name)
 		providers[idx] = &ProviderInstance{
 			BaseDN:              *provider.BaseDn,
 			GroupDN:             groupDN,
@@ -34,7 +37,18 @@ func (ls *LDAPServer) Refresh() error {
 			boundUsersMutex:     sync.RWMutex{},
 			boundUsers:          make(map[string]UserFlags),
 			s:                   ls,
-			log:                 log.WithField("logger", "authentik.outpost.ldap").WithField("provider", provider.Name),
+			log:                 logger,
+			tlsServerName:       provider.TlsServerName,
+		}
+		if provider.Certificate.Get() != nil {
+			logger.WithField("provider", provider.Name).Debug("Enabling TLS")
+			cert, err := ak.ParseCertificate(*provider.Certificate.Get(), ls.ac.Client.CryptoApi)
+			if err != nil {
+				logger.WithField("provider", provider.Name).WithError(err).Warning("Failed to fetch certificate")
+			} else {
+				providers[idx].cert = cert
+				logger.WithField("provider", provider.Name).Debug("Loaded certificates")
+			}
 		}
 	}
 	ls.providers = providers
@@ -58,9 +72,30 @@ func (ls *LDAPServer) StartLDAPServer() error {
 	return ls.s.ListenAndServe(listen)
 }
 
+func (ls *LDAPServer) StartLDAPTLSServer() error {
+	listen := "0.0.0.0:6636"
+	tlsConfig := &tls.Config{
+		MinVersion:     tls.VersionTLS12,
+		MaxVersion:     tls.VersionTLS12,
+		GetCertificate: ls.getCertificates,
+	}
+
+	ln, err := tls.Listen("tcp", listen, tlsConfig)
+	if err != nil {
+		ls.log.Fatalf("FATAL: listen (%s) failed - %s", listen, err)
+	}
+	ls.log.WithField("listen", listen).Info("Starting ldap tls server")
+	err = ls.s.Serve(ln)
+	if err != nil {
+		return err
+	}
+	ls.log.Printf("closing %s", ln.Addr())
+	return ls.s.ListenAndServe(listen)
+}
+
 func (ls *LDAPServer) Start() error {
 	wg := sync.WaitGroup{}
-	wg.Add(2)
+	wg.Add(3)
 	go func() {
 		defer wg.Done()
 		err := ls.StartHTTPServer()
@@ -75,6 +110,13 @@ func (ls *LDAPServer) Start() error {
 			panic(err)
 		}
 	}()
+	go func() {
+		defer wg.Done()
+		err := ls.StartLDAPTLSServer()
+		if err != nil {
+			panic(err)
+		}
+	}()
 	wg.Wait()
 	return nil
 }

outpost/pkg/ldap/api_tls.go

@@ -0,0 +1,23 @@
+package ldap
+
+import "crypto/tls"
+
+func (ls *LDAPServer) getCertificates(info *tls.ClientHelloInfo) (*tls.Certificate, error) {
+	if len(ls.providers) == 1 {
+		if ls.providers[0].cert != nil {
+			ls.log.WithField("server-name", info.ServerName).Debug("We only have a single provider, using their cert")
+			return ls.providers[0].cert, nil
+		}
+	}
+	for _, provider := range ls.providers {
+		if provider.tlsServerName == &info.ServerName {
+			if provider.cert == nil {
+				ls.log.WithField("server-name", info.ServerName).Debug("Handler does not have a certificate")
+				return ls.defaultCert, nil
+			}
+			return provider.cert, nil
+		}
+	}
+	ls.log.WithField("server-name", info.ServerName).Debug("Fallback to default cert")
+	return ls.defaultCert, nil
+}

outpost/pkg/ldap/instance_search.go

@@ -109,7 +109,7 @@ func (pi *ProviderInstance) UserEntry(u api.User) *ldap.Entry {
 
 	attrs = append(attrs, AKAttrsToLDAP(u.Attributes)...)
 
-	dn := fmt.Sprintf("cn=%s,%s", u.Username, pi.UserDN)
+	dn := pi.GetUserDN(u.Username)
 
 	return &ldap.Entry{DN: dn, Attributes: attrs}
 }
@@ -129,6 +129,9 @@ func (pi *ProviderInstance) GroupEntry(g api.Group) *ldap.Entry {
 			Values: []string{GroupObjectClass, "goauthentik.io/ldap/group"},
 		},
 	}
+	attrs = append(attrs, &ldap.EntryAttribute{Name: "member", Values: pi.UsersForGroup(g)})
+	attrs = append(attrs, &ldap.EntryAttribute{Name: "goauthentik.io/ldap/superuser", Values: []string{BoolToString(*g.IsSuperuser)}})
+
 	attrs = append(attrs, AKAttrsToLDAP(g.Attributes)...)
 
 	dn := pi.GetGroupDN(g)

outpost/pkg/ldap/ldap.go

@@ -1,6 +1,7 @@
 package ldap
 
 import (
+	"crypto/tls"
 	"sync"
 
 	"github.com/go-openapi/strfmt"
@@ -25,6 +26,9 @@ type ProviderInstance struct {
 	s        *LDAPServer
 	log      *log.Entry
 
+	tlsServerName *string
+	cert          *tls.Certificate
+
 	searchAllowedGroups []*strfmt.UUID
 	boundUsersMutex     sync.RWMutex
 	boundUsers          map[string]UserFlags
@@ -39,7 +43,7 @@ type LDAPServer struct {
 	s           *ldap.Server
 	log         *log.Entry
 	ac          *ak.APIController
-
+	defaultCert *tls.Certificate
 	providers   []*ProviderInstance
 }
 
@@ -52,6 +56,11 @@ func NewServer(ac *ak.APIController) *LDAPServer {
 		ac:        ac,
 		providers: []*ProviderInstance{},
 	}
+	defaultCert, err := ak.GenerateSelfSignedCert()
+	if err != nil {
+		log.Warning(err)
+	}
+	ls.defaultCert = &defaultCert
 	s.BindFunc("", ls)
 	s.SearchFunc("", ls)
 	return ls

outpost/pkg/ldap/utils.go

@@ -2,8 +2,10 @@ package ldap
 
 import (
 	"fmt"
+	"reflect"
 
 	"github.com/nmcclain/ldap"
+	log "github.com/sirupsen/logrus"
 	"goauthentik.io/outpost/api"
 )
 
@@ -14,6 +16,24 @@ func BoolToString(in bool) string {
 	return "false"
 }
 
+func ldapResolveTypeSingle(in interface{}) *string {
+	switch t := in.(type) {
+	case string:
+		return &t
+	case *string:
+		return t
+	case bool:
+		s := BoolToString(t)
+		return &s
+	case *bool:
+		s := BoolToString(*t)
+		return &s
+	default:
+		log.WithField("type", reflect.TypeOf(in).String()).Warning("Type can't be mapped to LDAP yet")
+		return nil
+	}
+}
+
 func AKAttrsToLDAP(attrs interface{}) []*ldap.EntryAttribute {
 	attrList := []*ldap.EntryAttribute{}
 	a := attrs.(*map[string]interface{})
@@ -22,10 +42,19 @@ func AKAttrsToLDAP(attrs interface{}) []*ldap.EntryAttribute {
 		switch t := attrValue.(type) {
 		case []string:
 			entry.Values = t
-		case string:
-			entry.Values = []string{t}
-		case bool:
-			entry.Values = []string{BoolToString(t)}
+		case *[]string:
+			entry.Values = *t
+		case []interface{}:
+			entry.Values = make([]string, len(t))
+			for idx, v := range t {
+				v := ldapResolveTypeSingle(v)
+				entry.Values[idx] = *v
+			}
+		default:
+			v := ldapResolveTypeSingle(t)
+			if v != nil {
+				entry.Values = []string{*v}
+			}
 		}
 		attrList = append(attrList, entry)
 	}
@@ -40,6 +69,18 @@ func (pi *ProviderInstance) GroupsForUser(user api.User) []string {
 	return groups
 }
 
+func (pi *ProviderInstance) UsersForGroup(group api.Group) []string {
+	users := make([]string, len(group.UsersObj))
+	for i, user := range group.UsersObj {
+		users[i] = pi.GetUserDN(user.Username)
+	}
+	return users
+}
+
+func (pi *ProviderInstance) GetUserDN(user string) string {
+	return fmt.Sprintf("cn=%s,%s", user, pi.UserDN)
+}
+
 func (pi *ProviderInstance) GetGroupDN(group api.Group) string {
 	return fmt.Sprintf("cn=%s,%s", group.Name, pi.GroupDN)
 }

outpost/pkg/proxy/api_bundle.go

@@ -1,7 +1,6 @@
 package proxy
 
 import (
-	"context"
 	"crypto/tls"
 	"net"
 	"net/http"
@@ -16,6 +15,7 @@ import (
 	"github.com/oauth2-proxy/oauth2-proxy/pkg/validation"
 	log "github.com/sirupsen/logrus"
 	"goauthentik.io/outpost/api"
+	"goauthentik.io/outpost/pkg/ak"
 )
 
 type providerBundle struct {
@@ -90,23 +90,12 @@ func (pb *providerBundle) prepareOpts(provider api.ProxyOutpostConfig) *options.
 
 	if provider.Certificate.Get() != nil {
 		pb.log.WithField("provider", provider.Name).Debug("Enabling TLS")
-		cert, _, err := pb.s.ak.Client.CryptoApi.CryptoCertificatekeypairsViewCertificateRetrieve(context.Background(), *provider.Certificate.Get()).Execute()
+		cert, err := ak.ParseCertificate(*provider.Certificate.Get(), pb.s.ak.Client.CryptoApi)
 		if err != nil {
 			pb.log.WithField("provider", provider.Name).WithError(err).Warning("Failed to fetch certificate")
 			return providerOpts
 		}
-		key, _, err := pb.s.ak.Client.CryptoApi.CryptoCertificatekeypairsViewPrivateKeyRetrieve(context.Background(), *provider.Certificate.Get()).Execute()
-		if err != nil {
-			pb.log.WithField("provider", provider.Name).WithError(err).Warning("Failed to fetch private key")
-			return providerOpts
-		}
-
-		x509cert, err := tls.X509KeyPair([]byte(cert.Data), []byte(key.Data))
-		if err != nil {
-			pb.log.WithField("provider", provider.Name).WithError(err).Warning("Failed to parse certificate")
-			return providerOpts
-		}
-		pb.cert = &x509cert
+		pb.cert = cert
 		pb.log.WithField("provider", provider.Name).Debug("Loaded certificates")
 	}
 	return providerOpts

schema.yml

@@ -19927,11 +19927,100 @@ components:
         attributes:
           type: object
           additionalProperties: {}
+        users_obj:
+          type: array
+          items:
+            $ref: '#/components/schemas/GroupMember'
+          readOnly: true
       required:
       - name
       - parent
       - pk
       - users
+      - users_obj
+    GroupMember:
+      type: object
+      description: Stripped down user serializer to show relevant users for groups
+      properties:
+        pk:
+          type: integer
+          readOnly: true
+          title: ID
+        username:
+          type: string
+          description: Required. 150 characters or fewer. Letters, digits and @/./+/-/_
+            only.
+          pattern: ^[\w.@+-]+$
+          maxLength: 150
+        name:
+          type: string
+          description: User's display name.
+        is_active:
+          type: boolean
+          title: Active
+          description: Designates whether this user should be treated as active. Unselect
+            this instead of deleting accounts.
+        last_login:
+          type: string
+          format: date-time
+          nullable: true
+        is_superuser:
+          type: boolean
+          readOnly: true
+        email:
+          type: string
+          format: email
+          title: Email address
+          maxLength: 254
+        avatar:
+          type: string
+          readOnly: true
+        attributes:
+          type: object
+          additionalProperties: {}
+        uid:
+          type: string
+          readOnly: true
+      required:
+      - avatar
+      - is_superuser
+      - name
+      - pk
+      - uid
+      - username
+    GroupMemberRequest:
+      type: object
+      description: Stripped down user serializer to show relevant users for groups
+      properties:
+        username:
+          type: string
+          description: Required. 150 characters or fewer. Letters, digits and @/./+/-/_
+            only.
+          pattern: ^[\w.@+-]+$
+          maxLength: 150
+        name:
+          type: string
+          description: User's display name.
+        is_active:
+          type: boolean
+          title: Active
+          description: Designates whether this user should be treated as active. Unselect
+            this instead of deleting accounts.
+        last_login:
+          type: string
+          format: date-time
+          nullable: true
+        email:
+          type: string
+          format: email
+          title: Email address
+          maxLength: 254
+        attributes:
+          type: object
+          additionalProperties: {}
+      required:
+      - name
+      - username
     GroupRequest:
       type: object
       description: Group Serializer
@@ -20402,6 +20491,12 @@ components:
           nullable: true
           description: Users in this group can do search queries. If not set, every
             user can execute search queries.
+        certificate:
+          type: string
+          format: uuid
+          nullable: true
+        tls_server_name:
+          type: string
       required:
       - application_slug
       - bind_flow_slug
@@ -20514,6 +20609,12 @@ components:
           nullable: true
           description: Users in this group can do search queries. If not set, every
             user can execute search queries.
+        certificate:
+          type: string
+          format: uuid
+          nullable: true
+        tls_server_name:
+          type: string
       required:
       - assigned_application_name
       - assigned_application_slug
@@ -20547,6 +20648,12 @@ components:
           nullable: true
           description: Users in this group can do search queries. If not set, every
             user can execute search queries.
+        certificate:
+          type: string
+          format: uuid
+          nullable: true
+        tls_server_name:
+          type: string
       required:
       - authorization_flow
       - name
@@ -24883,6 +24990,12 @@ components:
           nullable: true
           description: Users in this group can do search queries. If not set, every
             user can execute search queries.
+        certificate:
+          type: string
+          format: uuid
+          nullable: true
+        tls_server_name:
+          type: string
     PatchedLDAPSourceRequest:
       type: object
       description: LDAP Source Serializer

web/src/pages/providers/ldap/LDAPProviderForm.ts

@@ -1,4 +1,4 @@
-import { FlowsApi, ProvidersApi, LDAPProvider, CoreApi, FlowsInstancesListDesignationEnum } from "authentik-api";
+import { FlowsApi, ProvidersApi, LDAPProvider, CoreApi, FlowsInstancesListDesignationEnum, CryptoApi } from "authentik-api";
 import { t } from "@lingui/macro";
 import { customElement } from "lit-element";
 import { html, TemplateResult } from "lit-html";
@@ -90,6 +90,27 @@ export class LDAPProviderFormPage extends ModelForm<LDAPProvider, number> {
                         <input type="text" value="${first(this.instance?.baseDn, "DC=ldap,DC=goauthentik,DC=io")}" class="pf-c-form-control" required>
                         <p class="pf-c-form__helper-text">${t`LDAP DN under which bind requests and search requests can be made.`}</p>
                     </ak-form-element-horizontal>
+                    <ak-form-element-horizontal
+                        label=${t`TLS Server name`}
+                        name="baseDn">
+                        <input type="text" value="${first(this.instance?.tlsServerName, "")}" class="pf-c-form-control">
+                        <p class="pf-c-form__helper-text">${t`Server name for which this provider's certificate is valid for.`}</p>
+                    </ak-form-element-horizontal>
+                    <ak-form-element-horizontal
+                        label=${t`Certificate`}
+                        name="certificate">
+                        <select class="pf-c-form-control">
+                            <option value="" ?selected=${this.instance?.certificate === undefined}>---------</option>
+                            ${until(new CryptoApi(DEFAULT_CONFIG).cryptoCertificatekeypairsList({
+                                ordering: "pk",
+                                hasKey: true,
+                            }).then(keys => {
+                                return keys.results.map(key => {
+                                    return html`<option value=${ifDefined(key.pk)} ?selected=${this.instance?.certificate === key.pk}>${key.name}</option>`;
+                                });
+                            }), html`<option>${t`Loading...`}</option>`)}
+                        </select>
+                    </ak-form-element-horizontal>
                 </div>
             </ak-form-group>
         </form>`;

website/docs/outposts/ldap/ldap.md

@@ -22,7 +22,7 @@ You can bind using the DN `cn=<username>,ou=users,<base DN>`, or using the follo
 ldapsearch \
   -x \ # Only simple binds are currently supported
   -h *ip* \
-  -p 3389 \
+  -p 389 \
   -D 'cn=*user*,ou=users,DC=ldap,DC=goauthentik,DC=io' \ # Bind user and password
   -w '*password*' \
   -b 'ou=users,DC=ldap,DC=goauthentik,DC=io' \ # The search base
@@ -48,8 +48,15 @@ The following fields are current set for groups:
 
 - `cn`: The group's name
 - `uid`: Unique group identifier
+- `member`: A list of all DNs of the group's members
 - `objectClass`: A list of these strings:
   - "group"
   - "goauthentik.io/ldap/group"
 
 **Additionally**, for both users and groups, any attributes you set are also present as LDAP Attributes.
+
+## SSL
+
+You can also configure SSL for your LDAP Providers by selecting a certificate and a server name in the provider settings.
+
+This enables you to bind on port 636 using LDAPS, StartTLS is not supported.