<?php if (!defined('BASEPATH')) exit('No direct script access allowed');
/**
* MX_Acl - Access Control library
*
* Save this file as application/libraries/MX_Acl.php
* $autoload['libraries'] = array('mx_acl', ... );
* $config['cache_path'] must be set
*
* @copyright Copyright (c) Wiredesignz & Maxximus 2009-04-20
* @version 0.12
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
class MX_Acl
{
var $uri, $config, $session, $cache_path;
function MX_Acl($config = array()) {
$ci =& get_instance();
$ci->load->helper('url');
$ci->load->library('session');
/* PHP4 needs this helper */
if (floor(phpversion() < 5)) {
$ci->load->helper('strripos');
}
$this->uri =& $ci->uri;
$this->config = $config;
$this->session =& $ci->session;
$this->cache_path = $ci->config->item('cache_path');
/* previous flashdata is available to views */
$ci->load->vars($config['error_var'], $this->session->flashdata($config['error_var']));
/* run the access control check now */
($config['check_uri']) AND $this->check_uri();
}
/**
* Check the current uri and user privileges against the cached ACL array
* Redirect if access is denied
*
* @return void
*/
function check_uri() {
/* Load the cached access control list or show error */
(is_file($cached_acl = $this->cache_path.'mx_acl'.EXT)) OR show_error($this->config['error_msg']);
$acl = include $cached_acl;
/* Match current url to access list */
if (is_array($acl) AND $acl = $this->match_uri($this->current_uri(), $acl)) {
/* Check session group against access level group */
$allow_access = (bool)(in_array($this->session->userdata($this->config['session_var']), $acl['allowed']));
/* Additional check to allow IP addresses in range */
if ( ! $allow_access AND isset($acl['ipl'])) $allow_access = $this->check_ip($acl['ipl']);
if ($allow_access == FALSE) {
/* Set a return url into the session */
$this->session->set_userdata('return_url', $this->uri->uri_string());
/* set the error message... */
$error_msg = (isset($acl['error_msg'])) ? $acl['error_msg'] : $this->config['error_msg'];
/* set a flash message... */
$this->session->set_flashdata($this->config['error_var'], $error_msg);
/* redirect to absolute url */
die(header("Location: ".$acl['error_uri'], TRUE, 302));
}
}
}
/**
* Return the access control profile for a given url
*
* @return string
* @param string $current_uri
* @param array $acl
*/
function match_uri($current_uri, $acl) {
if (array_key_exists($current_uri, $acl)) {
return $acl[$current_uri];
} else {
if ($pos = strripos($current_uri, '/')) {
return $this->match_uri(substr($current_uri, 0, $pos), $acl);
}
}
}
/**
* Returns the first 2 or 3 segments from the current uri
*
* @return string
*/
function current_uri() {
if ($this->uri->total_segments() == 2) {
return $this->uri->slash_rsegment(1).$this->uri->rsegment(2);
}
return $this->uri->slash_rsegment(1).$this->uri->slash_rsegment(2).$this->uri->rsegment(3);
}
/**
* Checks the remote IP address against the specified $ipl array
*
* @return bool
* @param array $ipl
* @param string $remote_ip[optional]
*/
function check_ip($ipl, $remote_ip = NULL) {
/* Convert ip address into a double (for lousy OSes)*/
$remote_ip = floatval(ip2long(($this->session->userdata('ip_address'))));
/* Loop through the ip list array */
foreach ($ipl as $allowed_ip) {
/* Replace '*' (for IP ranges) with a suitable range number */
$min = str_replace("*", "0", $allowed_ip);
$max = str_replace("*", "255", $allowed_ip);
/* Check for a match */
if (($remote_ip >= floatval(ip2long($min))) AND ($remote_ip <= floatval(ip2long($max)))) {
return TRUE;
}
}
}
}
