Refactoring: rename modules -> pkg

Reasons to change:

1. Shorter than 'modules'
2. More generally used by other Go projects
3. Corresponds to the naming of '$GOPATH/pkg' directory

1 files changed, 249 insertions, 0 deletions

diff --git a/pkg/auth/ldap/ldap.go b/pkg/auth/ldap/ldap.go
new file mode 100644
index 00000000..78cd66a4
--- /dev/null
+++ b/pkg/auth/ldap/ldap.go
@@ -0,0 +1,249 @@
+// Copyright 2014 The Gogs Authors. 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 (
+	"crypto/tls"
+	"fmt"
+	"strings"
+
+	log "gopkg.in/clog.v1"
+	"gopkg.in/ldap.v2"
+)
+
+type SecurityProtocol int
+
+// Note: new type must be added at the end of list to maintain compatibility.
+const (
+	SECURITY_PROTOCOL_UNENCRYPTED SecurityProtocol = iota
+	SECURITY_PROTOCOL_LDAPS
+	SECURITY_PROTOCOL_START_TLS
+)
+
+// Basic LDAP authentication service
+type Source struct {
+	Name              string // canonical name (ie. corporate.ad)
+	Host              string // LDAP host
+	Port              int    // port number
+	SecurityProtocol  SecurityProtocol
+	SkipVerify        bool
+	BindDN            string // DN to bind with
+	BindPassword      string // Bind DN password
+	UserBase          string // Base search path for users
+	UserDN            string // Template for the DN of the user for simple auth
+	AttributeUsername string // Username attribute
+	AttributeName     string // First name attribute
+	AttributeSurname  string // Surname attribute
+	AttributeMail     string // E-mail attribute
+	AttributesInBind  bool   // fetch attributes in bind context (not user)
+	Filter            string // Query filter to validate entry
+	AdminFilter       string // Query filter to check if user is admin
+	Enabled           bool   // if this source is disabled
+}
+
+func (ls *Source) sanitizedUserQuery(username string) (string, bool) {
+	// See http://tools.ietf.org/search/rfc4515
+	badCharacters := "\x00()*\\"
+	if strings.ContainsAny(username, badCharacters) {
+		log.Trace("Username contains invalid query characters: %s", username)
+		return "", false
+	}
+
+	return fmt.Sprintf(ls.Filter, username), true
+}
+
+func (ls *Source) sanitizedUserDN(username string) (string, bool) {
+	// See http://tools.ietf.org/search/rfc4514: "special characters"
+	badCharacters := "\x00()*\\,='\"#+;<>"
+	if strings.ContainsAny(username, badCharacters) || strings.HasPrefix(username, " ") || strings.HasSuffix(username, " ") {
+		log.Trace("Username contains invalid query characters: %s", username)
+		return "", false
+	}
+
+	return fmt.Sprintf(ls.UserDN, username), true
+}
+
+func (ls *Source) findUserDN(l *ldap.Conn, name string) (string, bool) {
+	log.Trace("Search for LDAP user: %s", name)
+	if ls.BindDN != "" && ls.BindPassword != "" {
+		err := l.Bind(ls.BindDN, ls.BindPassword)
+		if err != nil {
+			log.Trace("Failed to bind as BindDN '%s': %v", ls.BindDN, err)
+			return "", false
+		}
+		log.Trace("Bound as BindDN: %s", ls.BindDN)
+	} else {
+		log.Trace("Proceeding with anonymous LDAP search")
+	}
+
+	// A search for the user.
+	userFilter, ok := ls.sanitizedUserQuery(name)
+	if !ok {
+		return "", false
+	}
+
+	log.Trace("Searching for DN using filter '%s' and base '%s'", userFilter, ls.UserBase)
+	search := ldap.NewSearchRequest(
+		ls.UserBase, ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0,
+		false, userFilter, []string{}, nil)
+
+	// Ensure we found a user
+	sr, err := l.Search(search)
+	if err != nil || len(sr.Entries) < 1 {
+		log.Trace("Failed search using filter '%s': %v", userFilter, err)
+		return "", false
+	} else if len(sr.Entries) > 1 {
+		log.Trace("Filter '%s' returned more than one user", userFilter)
+		return "", false
+	}
+
+	userDN := sr.Entries[0].DN
+	if userDN == "" {
+		log.Error(4, "LDAP search was successful, but found no DN!")
+		return "", false
+	}
+
+	return userDN, true
+}
+
+func dial(ls *Source) (*ldap.Conn, error) {
+	log.Trace("Dialing LDAP with security protocol '%v' without verifying: %v", ls.SecurityProtocol, ls.SkipVerify)
+
+	tlsCfg := &tls.Config{
+		ServerName:         ls.Host,
+		InsecureSkipVerify: ls.SkipVerify,
+	}
+	if ls.SecurityProtocol == SECURITY_PROTOCOL_LDAPS {
+		return ldap.DialTLS("tcp", fmt.Sprintf("%s:%d", ls.Host, ls.Port), tlsCfg)
+	}
+
+	conn, err := ldap.Dial("tcp", fmt.Sprintf("%s:%d", ls.Host, ls.Port))
+	if err != nil {
+		return nil, fmt.Errorf("Dial: %v", err)
+	}
+
+	if ls.SecurityProtocol == SECURITY_PROTOCOL_START_TLS {
+		if err = conn.StartTLS(tlsCfg); err != nil {
+			conn.Close()
+			return nil, fmt.Errorf("StartTLS: %v", err)
+		}
+	}
+
+	return conn, nil
+}
+
+func bindUser(l *ldap.Conn, userDN, passwd string) error {
+	log.Trace("Binding with userDN: %s", userDN)
+	err := l.Bind(userDN, passwd)
+	if err != nil {
+		log.Trace("LDAP authentication failed for '%s': %v", userDN, err)
+		return err
+	}
+	log.Trace("Bound successfully with userDN: %s", userDN)
+	return err
+}
+
+// searchEntry : search an LDAP source if an entry (name, passwd) is valid and in the specific filter
+func (ls *Source) SearchEntry(name, passwd string, directBind bool) (string, string, string, string, bool, bool) {
+	// See https://tools.ietf.org/search/rfc4513#section-5.1.2
+	if len(passwd) == 0 {
+		log.Trace("authentication failed for '%s' with empty password")
+		return "", "", "", "", false, false
+	}
+	l, err := dial(ls)
+	if err != nil {
+		log.Error(4, "LDAP connect failed for '%s': %v", ls.Host, err)
+		ls.Enabled = false
+		return "", "", "", "", false, false
+	}
+	defer l.Close()
+
+	var userDN string
+	if directBind {
+		log.Trace("LDAP will bind directly via UserDN template: %s", ls.UserDN)
+
+		var ok bool
+		userDN, ok = ls.sanitizedUserDN(name)
+		if !ok {
+			return "", "", "", "", false, false
+		}
+	} else {
+		log.Trace("LDAP will use BindDN")
+
+		var found bool
+		userDN, found = ls.findUserDN(l, name)
+		if !found {
+			return "", "", "", "", false, false
+		}
+	}
+
+	if directBind || !ls.AttributesInBind {
+		// binds user (checking password) before looking-up attributes in user context
+		err = bindUser(l, userDN, passwd)
+		if err != nil {
+			return "", "", "", "", false, false
+		}
+	}
+
+	userFilter, ok := ls.sanitizedUserQuery(name)
+	if !ok {
+		return "", "", "", "", false, false
+	}
+
+	log.Trace("Fetching attributes '%v', '%v', '%v', '%v' with filter '%s' and base '%s'", ls.AttributeUsername, ls.AttributeName, ls.AttributeSurname, ls.AttributeMail, userFilter, userDN)
+	search := ldap.NewSearchRequest(
+		userDN, ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false, userFilter,
+		[]string{ls.AttributeUsername, ls.AttributeName, ls.AttributeSurname, ls.AttributeMail},
+		nil)
+
+	sr, err := l.Search(search)
+	if err != nil {
+		log.Error(4, "LDAP search failed: %v", err)
+		return "", "", "", "", false, false
+	} else if len(sr.Entries) < 1 {
+		if directBind {
+			log.Error(4, "User filter inhibited user login")
+		} else {
+			log.Error(4, "LDAP search failed: 0 entries")
+		}
+
+		return "", "", "", "", false, false
+	}
+
+	username := sr.Entries[0].GetAttributeValue(ls.AttributeUsername)
+	firstname := sr.Entries[0].GetAttributeValue(ls.AttributeName)
+	surname := sr.Entries[0].GetAttributeValue(ls.AttributeSurname)
+	mail := sr.Entries[0].GetAttributeValue(ls.AttributeMail)
+
+	isAdmin := false
+	if len(ls.AdminFilter) > 0 {
+		log.Trace("Checking admin with filter '%s' and base '%s'", ls.AdminFilter, userDN)
+		search = ldap.NewSearchRequest(
+			userDN, ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false, ls.AdminFilter,
+			[]string{ls.AttributeName},
+			nil)
+
+		sr, err = l.Search(search)
+		if err != nil {
+			log.Error(4, "LDAP admin search failed: %v", err)
+		} else if len(sr.Entries) < 1 {
+			log.Error(4, "LDAP admin search failed: 0 entries")
+		} else {
+			isAdmin = true
+		}
+	}
+
+	if !directBind && ls.AttributesInBind {
+		// binds user (checking password) after looking-up attributes in BindDN context
+		err = bindUser(l, userDN, passwd)
+		if err != nil {
+			return "", "", "", "", false, false
+		}
+	}
+
+	return username, firstname, surname, mail, isAdmin, true
+}