<?php

// BEGIN CONSTANTS

$ldap_readonly_attrs = array(

		'uid'

		, 'objectClass'

		, 'userPassword'

		, 'homeDirectory'

		, 'uidNumber'

		, 'gidNumber'

	);

$ldap_field_names = array(

		'cn' => 'Common name'

		, 'uid' => 'Username'

		, 'givenName' => 'Given name'

		, 'sn' => 'Surname'

		, 'mail' => 'E-mail'

		, 'title' => 'Job title'

		, 'telephoneNumber' => 'Phone'

	);

$ldap_add_single = array(

		'title'

		, 'mail'

	);

$ldap_add_multiple = array(

		'telephoneNumber'

		, 'mobile'

		, 'mail'

		, 'sshPublicKey'

	);

// END CONSTANTS

global $_ldapconn;

$_ldapconn = ldap_connect($ldap_server);

if ( !$_ldapconn )

	die("Failed to connect to the LDAP database");

if ( !ldap_set_option($_ldapconn, LDAP_OPT_PROTOCOL_VERSION, 3) )

	die("Failed to set LDAP version to 3");

if ( !ldap_bind($_ldapconn, $ldap_manager['dn'], $ldap_manager['password']) )

	die("Failed to bind to LDAP as a manager");

register_shutdown_function(function() use ($_ldapconn)

	{

		ldap_unbind($_ldapconn);

	});

function ldap_escape($str)

{

	// FIXME escape properly

	return $str;

}

function ldap_get_user($username)

{

	global $_ldapconn, $ldap_user_basedn;

	static $cache = array();

	if ( isset($cache[$username]) )

		return $cache[$username];

	$search_filter = sprintf("(&(uid=%s)(objectClass=posixAccount))", ldap_escape($username));

	$search_result = ldap_search($_ldapconn, $ldap_user_basedn, $search_filter);

	if ( ldap_count_entries($_ldapconn, $search_result) !== 1 )

		return false;

	return $cache[$username] = ldap_array_cleanup(ldap_get_attributes($_ldapconn, ldap_first_entry($_ldapconn, $search_result)));

}

function ldap_get_group($group)

{

	global $_ldapconn, $ldap_group_basedn;

	$search_filter = sprintf("(&(cn=%s)(objectClass=posixGroup))", ldap_escape($group));

	$search_result = ldap_search($_ldapconn, $ldap_group_basedn, $search_filter);

	if ( ldap_count_entries($_ldapconn, $search_result) !== 1 )

		return false;

	$result = ldap_array_cleanup(ldap_get_attributes($_ldapconn, ldap_first_entry($_ldapconn, $search_result)));

	if ( !isset($result['memberUid']) )

		$result['memberUid'] = array();

	if ( !is_array($result['memberUid']) )

		$result['memberUid'] = array($result['memberUid']);

	return $result;

}

function ldap_update_user($user, $entry)

{

	global $_ldapconn;

	return ldap_modify($_ldapconn, ldap_make_user_dn($user), $entry);

}

function ldap_list_users()

{

	global $_ldapconn, $ldap_user_basedn;

	$search_result = ldap_search($_ldapconn, $ldap_user_basedn, '(objectClass=organizationalPerson)');

	$results = array();

	for ( $entry = ldap_first_entry($_ldapconn, $search_result);

			$entry;

			$entry = ldap_next_entry($_ldapconn, $entry) )

	{

		$entry_arr = ldap_array_cleanup(ldap_get_attributes($_ldapconn, $entry));

		$results[$entry_arr['uid']] = $entry_arr;

	}

	return $results;

}

function ldap_list_groups()

{

	global $_ldapconn, $ldap_group_basedn;

	$search_result = ldap_search($_ldapconn, $ldap_group_basedn, '(objectClass=posixGroup)');

	$results = array();

	for ( $entry = ldap_first_entry($_ldapconn, $search_result);

			$entry;

			$entry = ldap_next_entry($_ldapconn, $entry) )

	{

		$entry_arr = ldap_array_cleanup(ldap_get_attributes($_ldapconn, $entry));

		$results[$entry_arr['cn']] = $entry_arr;

	}

	return $results;

}

function ldap_array_cleanup($arr)

{

	global $ldap_add_multiple;

	$result = array();

	foreach ( $arr as $k => $v )

	{

		if ( is_int($k) || $k == 'count' )

			continue;

		if ( $v['count'] === 1 && !in_array($k, $ldap_add_multiple) )

			$v = $v[0];

		else

			unset($v['count']);

		$result[$k] = $v;

	}

	return $result;

}

function ldap_make_user_dn($username)

{

	global $ldap_user_basedn;

	return sprintf('uid=%s,%s', ldap_escape($username), $ldap_user_basedn);

}

function ldap_make_group_dn($group)

{

	global $ldap_group_basedn;

	return sprintf('cn=%s,%s', ldap_escape($group), $ldap_group_basedn);

}

function ldap_replace_attr($dn, $attribute, $value)

{

	global $_ldapconn;

	$ldif = array(

			$attribute => array($value)

		);

	return ldap_mod_replace($_ldapconn, $dn, $ldif);

}

function ldap_delete_user($username)

{

	global $_ldapconn, $ldap_user_basedn, $ldap_group_basedn;

	// remove user from all LDAP groups

	$search_filter = sprintf("(&(memberUid=%s)(objectClass=posixGroup))", ldap_escape($username));

	$search_result = ldap_search($_ldapconn, $ldap_group_basedn, $search_filter);

	for ( $entry = ldap_first_entry($_ldapconn, $search_result);

			$entry;

			$entry = ldap_next_entry($_ldapconn, $entry) )

	{

		$entry_arr = ldap_array_cleanup(ldap_get_attributes($_ldapconn, $entry));

		$dn = ldap_get_dn($_ldapconn, $entry);

		ldap_mod_del($_ldapconn, $dn, array('memberUid' => array($username)));

	}

	// delete user DN

	return ldap_delete($_ldapconn, ldap_make_user_dn($username));

}

function ldap_delete_group_member($gid, $uid)

{

	global $_ldapconn;

	return ldap_mod_del($_ldapconn, ldap_make_group_dn($gid), array('memberUid' => array($uid)));

}

function ldap_add_group_member($gid, $uid)

{

	global $_ldapconn;

	return ldap_mod_add($_ldapconn, ldap_make_group_dn($gid), array('memberUid' => array($uid)));

}

function get_next_available_uid()

{

	$users = ldap_list_users();

	$uids = array();

	foreach ( $users as $u )

		$uids[] = intval($u['uidNumber']);

	asort($uids);

	$uid = UID_MIN;

	$last_uid = $uids[0];

	foreach ( $uids as $u )

	{

		if ( $u > $last_uid + 1 && ($last_uid + 1) > UID_MIN )

		{

			return $last_uid + 1;

		}

		$last_uid = $u;

	}

	return max($uids) + 1;

}

function get_next_available_gid()

{

	$groups = ldap_list_groups();

	$gids = array();

	foreach ( $groups as $g )

		$gids[] = intval($g['gidNumber']);

	asort($gids);

	$gid = GID_MIN;

	$last_gid = $gids[0];

	foreach ( $gids as $g )

	{

		if ( $g > $last_gid + 1 && ($last_gid + 1) > GID_MIN )

		{

			return $last_gid + 1;

		}

		$last_gid = $g;

	}

	return max($gids) + 1;

}

function get_next_available_extension()

{

	$users = ldap_list_users();

	$exts = array();

	foreach ( $users as $u )

	{

		if ( !isset($u['telephoneNumber']) )

			continue;

		if ( !is_array($u['telephoneNumber']) )

			$u['telephoneNumber'] = array($u['telephoneNumber']);

		foreach ( $u['telephoneNumber'] as $n )

		{

			if ( preg_match('/^([0-9]+) \(extension\)$/', $n, $match) )

				$exts[] = intval($n);

		}

	}

	asort($exts);

	$ext = PHONE_EXT_MIN;

	$last_ext = PHONE_EXT_MIN - 1;

	foreach ( $exts as $e )

	{

		if ( $e > $last_ext + 1 && ($last_ext + 1) > UID_MIN )

		{

			return $last_ext + 1;

		}

		$last_ext = $e;

	}

	return count($exts) ? max($exts) + 1 : PHONE_EXT_MIN;

}

function ldap_create_user($username, $gn, $sn, $cn, $title)

{

	global $_ldapconn;

	$krb_realm = get_default_kerberos_realm();

	if ( !ldap_add($_ldapconn, ldap_make_user_dn($username), array(

			'cn' => array($cn)

			, 'uid' => array($username)

			, 'objectClass' => array(

				'top'

				, 'person'

				, 'inetOrgPerson'

				, 'organizationalPerson'

				, 'posixAccount'

				, 'ldapPublicKey'

				)

			, 'gn' => array($gn)

			, 'sn' => array($sn)

			, 'userPassword' => array("{SASL}$username@$krb_realm")

			, 'loginShell' => array('/bin/bash')

			, 'homeDirectory' => array("/home/users/$username")

			, 'uidNumber' => array(get_next_available_uid())

			, 'gidNumber' => array(500)

			, 'title' => array($title)

		)) )

		return false;

	if ( !ldap_mod_add($_ldapconn, ldap_make_group_dn('users'), array('memberUid' => array($username))) )

		return false;

	return true;

}

function ldap_create_group($cn, $description)

{

	global $_ldapconn;

	if ( !ldap_add($_ldapconn, ldap_make_group_dn($cn), array(

			'cn' => array($cn)

			, 'description' => array($description)

			, 'gidNumber' => array(get_next_available_gid())

			, 'objectClass' => array(

				'top'

				, 'posixGroup'

				)

		)) )

		return false;

}

function ldap_delete_group($cn)

{

	global $_ldapconn;

	$group = ldap_get_group($cn);

	$users = ldap_list_users();

	foreach ( $users as $u )

	{

		if ( $u['gidNumber'] === $group['gidNumber'] )

			return false;

	}

	return ldap_delete($_ldapconn, ldap_make_group_dn($cn));

}

/**

 * Is the given username in the specified LDAP group?

 * @param string username

 * @param string Group name

 * @return bool

 */

function ldap_test_group_membership($username, $group)

{

	global $_ldapconn, $ldap_group_basedn;

	$filter = sprintf('(&(memberUid=%s)(cn=%s)(objectClass=posixGroup))', ldap_escape($username), ldap_escape($group));

	$result = ldap_search($_ldapconn, $ldap_group_basedn, $filter);

	return ldap_count_entries($_ldapconn, $result) > 0;

}