<?php

class LDAP
{
    public $sAuthSource = '';
    public $aUserInfo = array();
    public $sSystem = '';
    public $sLdapLog = '';
    private static $instance = null;

    public function __construct()
    {

    }

    public function &getSingleton()
    {
        if (self::$instance == null) {
            self::$instance = new RBAC();
        }
        return self::$instance;
    }

    public function log($_link, $text)
    {
        $this->sLdapLog .= $text . ": " . @ldap_errno($_link) . ',' . @ldap_error($_link) . "\n";
    }

    /**
     * Autentificacion de un usuario a traves de la clase RBAC_user
     *
     * verifica que un usuario tiene derechos de iniciar una aplicacion
     *
     * @author Fernando Ontiveros Lira <fernando@colosa.com>
     * @access public

     * @param  string $strUser    UserId  (login) de usuario
     * @param  string $strPass    Password
     * @return
     *  -1: no existe usuario
     *  -2: password errado
     *  -3: usuario inactivo
     *  -4: usuario vencido
     *  n : uid de usuario
     */
    public function VerifyLogin($strUser, $strPass)
    {
        //get the AuthSource properties
        if (strlen($strPass) == 0) {
            return -2;
        }
        $RBAC = RBAC::getSingleton();
        $aAuthSource = $RBAC->authSourcesObj->load($this->sAuthSource);

        $sAuthHost = $aAuthSource['AUTH_SOURCE_SERVER_NAME'];
        $sAuthPort = $aAuthSource['AUTH_SOURCE_PORT'];
        $sAuthTls = $aAuthSource['AUTH_SOURCE_ENABLED_TLS'];
        $sAuthBaseDn = $aAuthSource['AUTH_SOURCE_BASE_DN'];
        $sAuthFilter = $aAuthSource['AUTH_SOURCE_OBJECT_CLASSES'];
        $sAuthType = 'AD';
        $sAuthVersion = $aAuthSource['AUTH_SOURCE_VERSION'];
        $aAttributes = $aAuthSource['AUTH_SOURCE_ATTRIBUTES']; //array ('dn',"cn", "samaccountname", "givenname", "sn", "mail");
        $sAuthUser = $aAuthSource['AUTH_SOURCE_SEARCH_USER'];
        $sAuthPass = $aAuthSource['AUTH_SOURCE_PASSWORD'];

        $_link = @ldap_connect($sAuthHost, $sAuthPort);
        $this->log($_link, "ldap connect");

        ldap_set_option($_link, LDAP_OPT_PROTOCOL_VERSION, $sAuthVersion);
        $this->log($_link, "ldap set Protocol Version $sAuthVersion");

        ldap_set_option($_link, LDAP_OPT_REFERRALS, 0);
        $this->log($_link, "ldap set option Referrals");

        if (isset($sAuthTls) && $sAuthTls) {
            @ldap_start_tls($_link);
            $this->log($_link, "start tls");
        }

        $bind = @ldap_bind($_link);
        $this->log($_link, "ldap bind anonymous");

        $validUserPass = @ldap_bind($_link, $strUser, $strPass);
        $this->log($_link, "ldap binding with user $strUser");

        return $validUserPass;
    }

    public function searchUsers($sKeyword)
    {
        $sKeyword = trim($sKeyword);
        $RBAC = RBAC::getSingleton();
        $aAuthSource = $RBAC->authSourcesObj->load($this->sAuthSource);
        $pass = explode("_", $aAuthSource['AUTH_SOURCE_PASSWORD']);
        foreach ($pass as $index => $value) {
            if ($value == '2NnV3ujj3w') {
                $aAuthSource['AUTH_SOURCE_PASSWORD'] = G::decrypt($pass[0],
                                                                  $aAuthSource['AUTH_SOURCE_SERVER_NAME']);
            }
        }
        $oLink = @ldap_connect($aAuthSource['AUTH_SOURCE_SERVER_NAME'],
                               $aAuthSource['AUTH_SOURCE_PORT']);
        @ldap_set_option($oLink, LDAP_OPT_PROTOCOL_VERSION,
                         $aAuthSource['AUTH_SOURCE_VERSION']);
        @ldap_set_option($oLink, LDAP_OPT_REFERRALS, 0);
        if (isset($aAuthSource['AUTH_SOURCE_ENABLED_TLS']) && $aAuthSource['AUTH_SOURCE_ENABLED_TLS']) {
            @ldap_start_tls($oLink);
        }
        if ($aAuthSource['AUTH_ANONYMOUS'] == '1') {
            $bBind = @ldap_bind($oLink);
        } else {
            $bBind = @ldap_bind($oLink, $aAuthSource['AUTH_SOURCE_SEARCH_USER'],
                                $aAuthSource['AUTH_SOURCE_PASSWORD']);
        }
        if (!$bBind) {
            throw new Exception('Unable to bind to server : ' . $aAuthSource['AUTH_SOURCE_SERVER_NAME'] . ' in port ' . $aAuthSource['AUTH_SOURCE_PORT']);
        }
        if (substr($sKeyword, -1) != '*') {
            if ($sKeyword != '') {
                $sKeyword = '*' . $sKeyword . '*';
            } else {
                $sKeyword .= '*';
            }
        }

        $additionalFilter = isset($aAuthSource['AUTH_SOURCE_DATA']['AUTH_SOURCE_ADDITIONAL_FILTER'])
                ? trim($aAuthSource['AUTH_SOURCE_DATA']['AUTH_SOURCE_ADDITIONAL_FILTER'])
                : '';

        $sFilter = '(&(|(objectClass=*))';

        if (isset($aAuthSource['AUTH_SOURCE_DATA']['LDAP_TYPE']) && $aAuthSource['AUTH_SOURCE_DATA']['LDAP_TYPE']
            == 'ad') {
            $sFilter = "(&(|(objectClass=*))(|(samaccountname=$sKeyword)(userprincipalname=$sKeyword))$additionalFilter)";
        } else {
            $sFilter = "(&(|(objectClass=*))(|(uid=$sKeyword)(cn=$sKeyword))$additionalFilter)";
        }

        $aUsers = array();
        $oSearch = @ldap_search($oLink, $aAuthSource['AUTH_SOURCE_BASE_DN'],
                                $sFilter,
                                array('dn', 'uid', 'samaccountname', 'cn', 'givenname',
                'sn', 'mail', 'userprincipalname', 'objectcategory', 'manager'));

        if ($oError = @ldap_errno($oLink)) {
            return $aUsers;
        } else {
            if ($oSearch) {
                if (@ldap_count_entries($oLink, $oSearch) > 0) {
                    $sUsername = '';
                    $oEntry = @ldap_first_entry($oLink, $oSearch);
                    $uidUser = isset($aAuthSource['AUTH_SOURCE_DATA']['AUTH_SOURCE_IDENTIFIER_FOR_USER'])
                            ? $aAuthSource['AUTH_SOURCE_DATA']['AUTH_SOURCE_IDENTIFIER_FOR_USER']
                            : 'uid';
                    do {
                        $aAttr = $this->getLdapAttributes($oLink, $oEntry);
                        $sUsername = isset($aAttr[$uidUser]) ? $aAttr[$uidUser] : '';
                        if ($sUsername != '') {
                            // note added by gustavo cruz gustavo-at-colosa.com
                            // assign the givenname and sn fields if these are set
                            $aUsers[] = [
                                'sUsername'  => $sUsername,
                                'sFullname'  => isset($aAttr['cn']) ? $aAttr['cn'] : '',
                                'sFirstname' => isset($aAttr['givenname']) ? $aAttr['givenname'] : '',
                                'sLastname'  => isset($aAttr['sn']) ? $aAttr['sn'] : '',
                                'sEmail'     => isset($aAttr['mail'])
                                    ? $aAttr['mail']
                                    : (isset($aAttr['userprincipalname']) ? $aAttr['userprincipalname'] : ''),
                                'sDN'        => $aAttr['dn']
                            ];
                        }
                    } while ($oEntry = @ldap_next_entry($oLink, $oEntry));
                }
            }
            return $aUsers;
        }
    }

    public function getLdapAttributes($oLink, $oEntry)
    {
        $aAttrib['dn'] = @ldap_get_dn($oLink, $oEntry);
        $aAttr = @ldap_get_attributes($oLink, $oEntry);
        for ($iAtt = 0; $iAtt < $aAttr['count']; $iAtt++) {
            switch ($aAttr[$aAttr[$iAtt]]['count']) {
                case 0: $aAttrib[strtolower($aAttr[$iAtt])] = '';
                    break;
                case 1: $aAttrib[strtolower($aAttr[$iAtt])] = $aAttr[$aAttr[$iAtt]][0];
                    break;
                default:
                    $aAttrib[strtolower($aAttr[$iAtt])] = $aAttr[$aAttr[$iAtt]];
                    unset($aAttrib[$aAttr[$iAtt]]['count']);
                    break;
            }
        }
        return $aAttrib;
    }
}