<?php
use dokuwiki\Extension\AuthPlugin;
use dokuwiki\PassHash;
use dokuwiki\Utf8\Sort;
/**
* LDAP authentication backend
*
* @license GPL 2 (http://www.gnu.org/licenses/gpl.html)
* @author Andreas Gohr <andi@splitbrain.org>
* @author Chris Smith <chris@jalakaic.co.uk>
* @author Jan Schumann <js@schumann-it.com>
*/
class auth_plugin_authldap extends AuthPlugin
{
/* @var resource $con holds the LDAP connection */
protected $con;
/* @var int $bound What type of connection does already exist? */
protected $bound = 0; // 0: anonymous, 1: user, 2: superuser
/* @var array $users User data cache */
protected $users;
/* @var array $pattern User filter pattern */
protected $pattern;
/**
* Constructor
*/
public function __construct()
{
parent::__construct();
// ldap extension is needed
if (!function_exists('ldap_connect')) {
$this->debug("LDAP err: PHP LDAP extension not found.", -1, __LINE__, __FILE__);
$this->success = false;
return;
}
// Add the capabilities to change the password
$this->cando['modPass'] = $this->getConf('modPass');
}
/**
* Check user+password
*
* Checks if the given user exists and the given
* plaintext password is correct by trying to bind
* to the LDAP server
*
* @param string $user
* @param string $pass
* @return bool
* @author Andreas Gohr <andi@splitbrain.org>
*/
public function checkPass($user, $pass)
{
// reject empty password
if (empty($pass)) return false;
if (!$this->openLDAP()) return false;
// indirect user bind
if ($this->getConf('binddn') && $this->getConf('bindpw')) {
// use superuser credentials
if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
$this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
return false;
}
$this->bound = 2;
} elseif (
$this->getConf('binddn') &&
$this->getConf('usertree') &&
$this->getConf('userfilter')
) {
// special bind string
$dn = $this->makeFilter(
$this->getConf('binddn'),
['user' => $user, 'server' => $this->getConf('server')]
);
} elseif (strpos($this->getConf('usertree'), '%{user}')) {
// direct user bind
$dn = $this->makeFilter(
$this->getConf('usertree'),
['user' => $user, 'server' => $this->getConf('server')]
);
} elseif (!@ldap_bind($this->con)) {
// Anonymous bind
msg("LDAP: can not bind anonymously", -1);
$this->debug('LDAP anonymous bind: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
return false;
}
// Try to bind to with the dn if we have one.
if (!empty($dn)) {
// User/Password bind
if (!@ldap_bind($this->con, $dn, $pass)) {
$this->debug("LDAP: bind with $dn failed", -1, __LINE__, __FILE__);
$this->debug('LDAP user dn bind: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
return false;
}
$this->bound = 1;
return true;
} else {
// See if we can find the user
$info = $this->fetchUserData($user, true);
if (empty($info['dn'])) {
return false;
} else {
$dn = $info['dn'];
}
// Try to bind with the dn provided
if (!@ldap_bind($this->con, $dn, $pass)) {
$this->debug("LDAP: bind with $dn failed", -1, __LINE__, __FILE__);
$this->debug('LDAP user bind: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
return false;
}
$this->bound = 1;
return true;
}
}
/**
* Return user info
*
* Returns info about the given user needs to contain
* at least these fields:
*
* name string full name of the user
* mail string email addres of the user
* grps array list of groups the user is in
*
* This LDAP specific function returns the following
* addional fields:
*
* dn string distinguished name (DN)
* uid string Posix User ID
* inbind bool for internal use - avoid loop in binding
*
* @param string $user
* @param bool $requireGroups (optional) - ignored, groups are always supplied by this plugin
* @return array containing user data or false
* @author <evaldas.auryla@pheur.org>
* @author Stephane Chazelas <stephane.chazelas@emerson.com>
* @author Steffen Schoch <schoch@dsb.net>
*
* @author Andreas Gohr <andi@splitbrain.org>
* @author Trouble
* @author Dan Allen <dan.j.allen@gmail.com>
*/
public function getUserData($user, $requireGroups = true)
{
return $this->fetchUserData($user);
}
/**
* @param string $user
* @param bool $inbind authldap specific, true if in bind phase
* @return array containing user data or false
*/
protected function fetchUserData($user, $inbind = false)
{
global $conf;
if (!$this->openLDAP()) return [];
// force superuser bind if wanted and not bound as superuser yet
if ($this->getConf('binddn') && $this->getConf('bindpw') && $this->bound < 2) {
// use superuser credentials
if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
$this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
return [];
}
$this->bound = 2;
} elseif ($this->bound == 0 && !$inbind) {
// in some cases getUserData is called outside the authentication workflow
// eg. for sending email notification on subscribed pages. This data might not
// be accessible anonymously, so we try to rebind the current user here
[$loginuser, $loginsticky, $loginpass] = auth_getCookie();
if ($loginuser && $loginpass) {
$loginpass = auth_decrypt($loginpass, auth_cookiesalt(!$loginsticky, true));
$this->checkPass($loginuser, $loginpass);
}
}
$info = [];
$info['user'] = $user;
$this->debug('LDAP user to find: ' . hsc($info['user']), 0, __LINE__, __FILE__);
$info['server'] = $this->getConf('server');
$this->debug('LDAP Server: ' . hsc($info['server']), 0, __LINE__, __FILE__);
//get info for given user
$base = $this->makeFilter($this->getConf('usertree'), $info);
if ($this->getConf('userfilter')) {
$filter = $this->makeFilter($this->getConf('userfilter'), $info);
} else {
$filter = "(ObjectClass=*)";
}
$this->debug('LDAP Filter: ' . hsc($filter), 0, __LINE__, __FILE__);
$this->debug('LDAP search at: ' . hsc($base . ' ' . $filter), 0, __LINE__, __FILE__);
$sr = $this->ldapSearch($this->con, $base, $filter, $this->getConf('userscope'), $this->getConf('attributes'));
$this->debug('LDAP user search: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
if ($sr === false) {
$this->debug('User ldap_search failed. Check configuration.', 0, __LINE__, __FILE__);
return false;
}
$result = @ldap_get_entries($this->con, $sr);
// if result is not an array
if (!is_array($result)) {
// no objects found
$this->debug('LDAP search returned non-array result: ' . hsc(print($result)), -1, __LINE__, __FILE__);
return [];
}
// Don't accept more or less than one response
if ($result['count'] != 1) {
$this->debug(
'LDAP search returned ' . hsc($result['count']) . ' results while it should return 1!',
-1,
__LINE__,
__FILE__
);
//for($i = 0; $i < $result["count"]; $i++) {
//$this->_debug('result: '.hsc(print_r($result[$i])), 0, __LINE__, __FILE__);
//}
return [];
}
$this->debug('LDAP search found single result !', 0, __LINE__, __FILE__);
$user_result = $result[0];
ldap_free_result($sr);
// general user info
$info['dn'] = $user_result['dn'];
$info['gid'] = $user_result['gidnumber'][0] ?? null;
$info['mail'] = $user_result['mail'][0];
$info['name'] = $user_result['cn'][0];
$info['grps'] = [];
// overwrite if other attribs are specified.
if (is_array($this->getConf('mapping'))) {
foreach ($this->getConf('mapping') as $localkey => $key) {
if (is_array($key)) {
// use regexp to clean up user_result
// $key = array($key=>$regexp), only handles the first key-value
$regexp = current($key);
$key = key($key);
if (is_array($user_result[$key] ?? null)) foreach ($user_result[$key] as $grpkey => $grp) {
if ($grpkey !== 'count' && preg_match($regexp, $grp, $match)) {
if ($localkey == 'grps') {
$info[$localkey][] = $match[1];
} else {
$info[$localkey] = $match[1];
}
}
}
} else {
$info[$localkey] = $user_result[$key][0];
}
}
}
$user_result = array_merge($info, $user_result);
//get groups for given user if grouptree is given
if ($this->getConf('grouptree') || $this->getConf('groupfilter')) {
$base = $this->makeFilter($this->getConf('grouptree'), $user_result);
$filter = $this->makeFilter($this->getConf('groupfilter'), $user_result);
$sr = $this->ldapSearch(
$this->con,
$base,
$filter,
$this->getConf('groupscope'),
[$this->getConf('groupkey')]
);
$this->debug('LDAP group search: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
$this->debug('LDAP search at: ' . hsc($base . ' ' . $filter), 0, __LINE__, __FILE__);
if (!$sr) {
msg("LDAP: Reading group memberships failed", -1);
return [];
}
$result = ldap_get_entries($this->con, $sr);
ldap_free_result($sr);
if (is_array($result)) foreach ($result as $grp) {
if (!empty($grp[$this->getConf('groupkey')])) {
$group = $grp[$this->getConf('groupkey')];
if (is_array($group)) {
$group = $group[0];
} else {
$this->debug('groupkey did not return a detailled result', 0, __LINE__, __FILE__);
}
if ($group === '') continue;
$this->debug('LDAP usergroup: ' . hsc($group), 0, __LINE__, __FILE__);
$info['grps'][] = $group;
}
}
}
// always add the default group to the list of groups
if (!$info['grps'] || !in_array($conf['defaultgroup'], $info['grps'])) {
$info['grps'][] = $conf['defaultgroup'];
}
return $info;
}
/**
* Definition of the function modifyUser in order to modify the password
*
* @param string $user nick of the user to be changed
* @param array $changes array of field/value pairs to be changed (password will be clear text)
* @return bool true on success, false on error
*/
public function modifyUser($user, $changes)
{
// open the connection to the ldap
if (!$this->openLDAP()) {
$this->debug('LDAP cannot connect: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
return false;
}
// find the information about the user, in particular the "dn"
$info = $this->getUserData($user, true);
if (empty($info['dn'])) {
$this->debug('LDAP cannot find your user dn', 0, __LINE__, __FILE__);
return false;
}
$dn = $info['dn'];
// find the old password of the user
[$loginuser, $loginsticky, $loginpass] = auth_getCookie();
if ($loginuser !== null) { // the user is currently logged in
$secret = auth_cookiesalt(!$loginsticky, true);
$pass = auth_decrypt($loginpass, $secret);
// bind with the ldap
if (!@ldap_bind($this->con, $dn, $pass)) {
$this->debug(
'LDAP user bind failed: ' . hsc($dn) . ': ' . hsc(ldap_error($this->con)),
0,
__LINE__,
__FILE__
);
return false;
}
} elseif ($this->getConf('binddn') && $this->getConf('bindpw')) {
// we are changing the password on behalf of the user (eg: forgotten password)
// bind with the superuser ldap
if (!@ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')))) {
$this->debug('LDAP bind as superuser: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
return false;
}
} else {
return false; // no otherway
}
// Generate the salted hashed password for LDAP
if ($this->getConf('modPassPlain')) {
$hash = $changes['pass'];
} else {
$phash = new PassHash();
$hash = $phash->hash_ssha($changes['pass']);
}
// change the password
if (!@ldap_mod_replace($this->con, $dn, ['userpassword' => $hash])) {
$this->debug(
'LDAP mod replace failed: ' . hsc($dn) . ': ' . hsc(ldap_error($this->con)),
0,
__LINE__,
__FILE__
);
return false;
}
return true;
}
/**
* Most values in LDAP are case-insensitive
*
* @return bool
*/
public function isCaseSensitive()
{
return false;
}
/**
* Bulk retrieval of user data
*
* @param int $start index of first user to be returned
* @param int $limit max number of users to be returned
* @param array $filter array of field/pattern pairs, null for no filter
* @return array of userinfo (refer getUserData for internal userinfo details)
* @author Dominik Eckelmann <dokuwiki@cosmocode.de>
*/
public function retrieveUsers($start = 0, $limit = 0, $filter = [])
{
if (!$this->openLDAP()) return [];
if (is_null($this->users)) {
// Perform the search and grab all their details
if ($this->getConf('userfilter')) {
$all_filter = str_replace('%{user}', '*', $this->getConf('userfilter'));
} else {
$all_filter = "(ObjectClass=*)";
}
$sr = ldap_search($this->con, $this->getConf('usertree'), $all_filter);
$entries = ldap_get_entries($this->con, $sr);
$users_array = [];
$userkey = $this->getConf('userkey');
for ($i = 0; $i < $entries["count"]; $i++) {
$users_array[] = $entries[$i][$userkey][0];
}
Sort::asort($users_array);
$result = $users_array;
if (!$result) return [];
$this->users = array_fill_keys($result, false);
}
$i = 0;
$count = 0;
$this->constructPattern($filter);
$result = [];
foreach ($this->users as $user => &$info) {
if ($i++ < $start) {
continue;
}
if ($info === false) {
$info = $this->getUserData($user);
}
if ($this->filter($user, $info)) {
$result[$user] = $info;
if (($limit > 0) && (++$count >= $limit)) break;
}
}
return $result;
}
/**
* Make LDAP filter strings.
*
* Used by auth_getUserData to make the filter
* strings for grouptree and groupfilter
*
* @param string $filter ldap search filter with placeholders
* @param array $placeholders placeholders to fill in
* @return string
* @author Troels Liebe Bentsen <tlb@rapanden.dk>
*/
protected function makeFilter($filter, $placeholders)
{
preg_match_all("/%{([^}]+)/", $filter, $matches, PREG_PATTERN_ORDER);
//replace each match
foreach ($matches[1] as $match) {
//take first element if array
if (is_array($placeholders[$match])) {
$value = $placeholders[$match][0];
} else {
$value = $placeholders[$match];
}
$value = $this->filterEscape($value);
$filter = str_replace('%{' . $match . '}', $value, $filter);
}
return $filter;
}
/**
* return true if $user + $info match $filter criteria, false otherwise
*
* @param string $user the user's login name
* @param array $info the user's userinfo array
* @return bool
* @author Chris Smith <chris@jalakai.co.uk>
*
*/
protected function filter($user, $info)
{
foreach ($this->pattern as $item => $pattern) {
if ($item == 'user') {
if (!preg_match($pattern, $user)) return false;
} elseif ($item == 'grps') {
if (!count(preg_grep($pattern, $info['grps']))) return false;
} elseif (!preg_match($pattern, $info[$item])) {
return false;
}
}
return true;
}
/**
* Set the filter pattern
*
* @param $filter
* @return void
* @author Chris Smith <chris@jalakai.co.uk>
*
*/
protected function constructPattern($filter)
{
$this->pattern = [];
foreach ($filter as $item => $pattern) {
$this->pattern[$item] = '/' . str_replace('/', '\/', $pattern) . '/i'; // allow regex characters
}
}
/**
* Escape a string to be used in a LDAP filter
*
* Ported from Perl's Net::LDAP::Util escape_filter_value
*
* @param string $string
* @return string
* @author Andreas Gohr
*/
protected function filterEscape($string)
{
// see https://github.com/adldap/adLDAP/issues/22
return preg_replace_callback(
'/([\x00-\x1F\*\(\)\\\\])/',
static fn($matches) => "\\" . implode("", unpack("H2", $matches[1])),
$string
);
}
/**
* Opens a connection to the configured LDAP server and sets the wanted
* option on the connection
*
* @author Andreas Gohr <andi@splitbrain.org>
*/
protected function openLDAP()
{
if ($this->con) return true; // connection already established
if ($this->getConf('debug')) {
ldap_set_option(null, LDAP_OPT_DEBUG_LEVEL, 7);
}
$this->bound = 0;
$port = $this->getConf('port');
$bound = false;
$servers = explode(',', $this->getConf('server'));
foreach ($servers as $server) {
$server = trim($server);
if (str_starts_with($server, 'ldap://') || str_starts_with($server, 'ldaps://')) {
$this->con = @ldap_connect($server);
} else {
$this->con = @ldap_connect($server, $port);
}
if (!$this->con) {
continue;
}
/*
* When OpenLDAP 2.x.x is used, ldap_connect() will always return a resource as it does
* not actually connect but just initializes the connecting parameters. The actual
* connect happens with the next calls to ldap_* funcs, usually with ldap_bind().
*
* So we should try to bind to server in order to check its availability.
*/
//set protocol version and dependend options
if ($this->getConf('version')) {
if (
!@ldap_set_option(
$this->con,
LDAP_OPT_PROTOCOL_VERSION,
$this->getConf('version')
)
) {
msg('Setting LDAP Protocol version ' . $this->getConf('version') . ' failed', -1);
$this->debug('LDAP version set: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
} else {
//use TLS (needs version 3)
if ($this->getConf('starttls')) {
if (!@ldap_start_tls($this->con)) {
msg('Starting TLS failed', -1);
$this->debug('LDAP TLS set: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
}
}
// needs version 3
if ($this->getConf('referrals') > -1) {
if (
!@ldap_set_option(
$this->con,
LDAP_OPT_REFERRALS,
$this->getConf('referrals')
)
) {
msg('Setting LDAP referrals failed', -1);
$this->debug('LDAP referal set: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
}
}
}
}
//set deref mode
if ($this->getConf('deref')) {
if (!@ldap_set_option($this->con, LDAP_OPT_DEREF, $this->getConf('deref'))) {
msg('Setting LDAP Deref mode ' . $this->getConf('deref') . ' failed', -1);
$this->debug('LDAP deref set: ' . hsc(ldap_error($this->con)), 0, __LINE__, __FILE__);
}
}
/* As of PHP 5.3.0 we can set timeout to speedup skipping of invalid servers */
if (defined('LDAP_OPT_NETWORK_TIMEOUT')) {
ldap_set_option($this->con, LDAP_OPT_NETWORK_TIMEOUT, 1);
}
if ($this->getConf('binddn') && $this->getConf('bindpw')) {
$bound = @ldap_bind($this->con, $this->getConf('binddn'), conf_decodeString($this->getConf('bindpw')));
$this->bound = 2;
} else {
$bound = @ldap_bind($this->con);
}
if ($bound) {
break;
}
}
if (!$bound) {
msg("LDAP: couldn't connect to LDAP server", -1);
$this->debug(ldap_error($this->con), 0, __LINE__, __FILE__);
return false;
}
$this->cando['getUsers'] = true;
return true;
}
/**
* Wraps around ldap_search, ldap_list or ldap_read depending on $scope
*
* @param resource $link_identifier
* @param string $base_dn
* @param string $filter
* @param string $scope can be 'base', 'one' or 'sub'
* @param null|array $attributes
* @param int $attrsonly
* @param int $sizelimit
* @return resource
* @author Andreas Gohr <andi@splitbrain.org>
*/
protected function ldapSearch(
$link_identifier,
$base_dn,
$filter,
$scope = 'sub',
$attributes = null,
$attrsonly = 0,
$sizelimit = 0
) {
if (is_null($attributes)) $attributes = [];
if ($scope == 'base') {
return @ldap_read(
$link_identifier,
$base_dn,
$filter,
$attributes,
$attrsonly,
$sizelimit
);
} elseif ($scope == 'one') {
return @ldap_list(
$link_identifier,
$base_dn,
$filter,
$attributes,
$attrsonly,
$sizelimit
);
} else {
return @ldap_search(
$link_identifier,
$base_dn,
$filter,
$attributes,
$attrsonly,
$sizelimit
);
}
}
/**
* Wrapper around msg() but outputs only when debug is enabled
*
* @param string $message
* @param int $err
* @param int $line
* @param string $file
* @return void
*/
protected function debug($message, $err, $line, $file)
{
if (!$this->getConf('debug')) return;
msg($message, $err, $line, $file);
}
}