outposts: initial ldap outpost implementation

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

outpost/pkg/ldap/ldap.go

@@ -0,0 +1,42 @@
+package ldap
+
+import (
+	"fmt"
+	"strings"
+
+	log "github.com/sirupsen/logrus"
+	"goauthentik.io/outpost/pkg/ak"
+
+	"github.com/nmcclain/ldap"
+)
+
+const GroupObjectClass = "group"
+const UserObjectClass = "user"
+
+type LDAPServer struct {
+	BaseDN string
+
+	userDN  string
+	groupDN string
+
+	s   *ldap.Server
+	log *log.Entry
+	ac  *ak.APIController
+}
+
+func NewServer(ac *ak.APIController) *LDAPServer {
+	s := ldap.NewServer()
+	s.EnforceLDAP = true
+	ls := &LDAPServer{
+		s:   s,
+		log: log.WithField("logger", "ldap-server"),
+		ac:  ac,
+
+		BaseDN: "DC=ldap,DC=goauthentik,DC=io",
+	}
+	ls.userDN = strings.ToLower(fmt.Sprintf("cn=users,%s", ls.BaseDN))
+	ls.groupDN = strings.ToLower(fmt.Sprintf("cn=groups,%s", ls.BaseDN))
+	s.BindFunc("", ls)
+	s.SearchFunc("", ls)
+	return ls
+}