From c1de814a2a7e7b8639c746afca65e12a26b99d78 Mon Sep 17 00:00:00 2001
From: Alexandre Iooss <erdnaxe@crans.org>
Date: Tue, 22 Sep 2020 14:16:52 +0200
Subject: [PATCH] Use NewLDAP to instanciate LDAP backend

---
 auth/auth.go      |  7 ++++++-
 auth/ldap/ldap.go | 28 +++++++++++++++++++---------
 main.go           |  6 +++++-
 3 files changed, 30 insertions(+), 11 deletions(-)

diff --git a/auth/auth.go b/auth/auth.go
index 127c0f0..9503ce3 100644
--- a/auth/auth.go
+++ b/auth/auth.go
@@ -15,14 +15,19 @@ type Options struct {
 // Backend to log user in
 type Backend interface {
 	Login(string, string) (bool, error)
+	Close()
 }
 
 // New initialize authentification backend
 func New(cfg *Options) (Backend, error) {
 	var backend Backend
+	var err error
 
 	if cfg.Backend == "LDAP" {
-		backend = ldap.LDAP{Cfg: cfg.LDAP}
+		backend, err = ldap.NewLDAP(&cfg.LDAP)
+		if err != nil {
+			return nil, err
+		}
 	} else {
 		// Package is misconfigured
 		return nil, errors.New("Authentification backend not found")
diff --git a/auth/ldap/ldap.go b/auth/ldap/ldap.go
index e6d9336..0dba25f 100644
--- a/auth/ldap/ldap.go
+++ b/auth/ldap/ldap.go
@@ -12,21 +12,16 @@ type Options struct {
 
 // LDAP authentification backend
 type LDAP struct {
-	Cfg Options
+	Cfg  *Options
+	Conn *ldap.Conn
 }
 
 // Login tries to bind to LDAP
 // Returns (true, nil) if success
 func (a LDAP) Login(username string, password string) (bool, error) {
-	// Connect to LDAP server
-	l, err := ldap.DialURL(a.Cfg.URI)
-	if err != nil {
-		return false, err
-	}
-	defer l.Close()
-
 	// Try to bind as user
-	err = l.Bind("cn=username,dc=example,dc=com", password)
+	bindDn := "cn=" + username + "," + a.Cfg.UserDn
+	err := a.Conn.Bind(bindDn, password)
 	if err != nil {
 		return false, err
 	}
@@ -34,3 +29,18 @@ func (a LDAP) Login(username string, password string) (bool, error) {
 	// Login succeeded
 	return true, nil
 }
+
+// Close LDAP connection
+func (a LDAP) Close() {
+	a.Conn.Close()
+}
+
+// NewLDAP instanciate a new LDAP connection
+func NewLDAP(cfg *Options) (LDAP, error) {
+	backend := LDAP{Cfg: cfg}
+
+	// Connect to LDAP server
+	c, err := ldap.DialURL(backend.Cfg.URI)
+	backend.Conn = c
+	return backend, err
+}
diff --git a/main.go b/main.go
index 082a919..1c5e666 100644
--- a/main.go
+++ b/main.go
@@ -62,7 +62,11 @@ func main() {
 	}
 
 	// Init authentification
-	//authBackend := auth.New(&cfg.Auth)
+	authBackend, err := auth.New(&cfg.Auth)
+	if err != nil {
+		log.Fatalln("Failed to load authentification backend:", err)
+	}
+	defer authBackend.Close()
 
 	// Start web server routine
 	go func() {