initial support for LDAP authentication/MSAD

modules/auth/ldap/ldap.go

@@ -0,0 +1,86 @@
+// Copyright github.com/juju2013. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+// package ldap provide functions & structure to query a LDAP ldap directory
+// For now, it's mainly tested again an MS Active Directory service, see README.md for more information
+package ldap
+
+import (
+	"fmt"
+	"github.com/gogits/gogs/modules/log"
+	goldap "github.com/juju2013/goldap"
+)
+
+// Basic LDAP authentication service
+type ldapsource struct {
+	Name         string // canonical name (ie. corporate.ad)
+	Host         string // LDAP host
+	Port         int    // port number
+	BaseDN       string // Base DN
+	Attributes   string // Attribut to search
+	Filter       string // Query filter to validate entry
+	MsAdSAFormat string // in the case of MS AD Simple Authen, the format to use (see: http://msdn.microsoft.com/en-us/library/cc223499.aspx)
+	Enabled      bool   // if this source is disabled
+}
+
+//Global LDAP directory pool
+var (
+	Authensource []ldapsource
+)
+
+// Add a new source (LDAP directory) to the global pool
+func AddSource(name string, host string, port int, basedn string, attributes string, filter string, msadsaformat string) {
+	ldaphost := ldapsource{name, host, port, basedn, attributes, filter, msadsaformat, true}
+	Authensource = append(Authensource, ldaphost)
+}
+
+//LoginUser : try to login an user to LDAP sources, return requested (attribut,true) if ok, ("",false) other wise
+//First match wins
+//Returns first attribute if exists
+func LoginUser(name, passwd string) (a string, r bool) {
+	r = false
+	for _, ls := range Authensource {
+		a, r = ls.searchEntry(name, passwd)
+		if r {
+			return
+		}
+	}
+	return
+}
+
+// searchEntry : search an LDAP source if an entry (name, passwd) is valide and in the specific filter
+func (ls ldapsource) searchEntry(name, passwd string) (string, bool) {
+	l, err := goldap.Dial("tcp", fmt.Sprintf("%s:%d", ls.Host, ls.Port))
+	if err != nil {
+		log.Debug("LDAP Connect error, disabled source %s", ls.Host)
+		ls.Enabled = false
+		return "", false
+	}
+	defer l.Close()
+
+	nx := fmt.Sprintf(ls.MsAdSAFormat, name)
+	err = l.Bind(nx, passwd)
+	if err != nil {
+		log.Debug("LDAP Authan failed for %s, reason: %s", nx, err.Error())
+		return "", false
+	}
+
+	search := goldap.NewSearchRequest(
+		ls.BaseDN,
+		goldap.ScopeWholeSubtree, goldap.NeverDerefAliases, 0, 0, false,
+		fmt.Sprintf(ls.Filter, name),
+		[]string{ls.Attributes},
+		nil)
+	sr, err := l.Search(search)
+	if err != nil {
+		log.Debug("LDAP Authen OK but not in filter %s", name)
+		return "", false
+	}
+	log.Debug("LDAP Authen OK: %s", name)
+	if len(sr.Entries) > 0 {
+		r := sr.Entries[0].GetAttributeValue(ls.Attributes)
+		return r, true
+	}
+	return "", true
+}