Extension:SimpleSecurity

<?php

1. Simple security extensionTemplate:Php

These are the MediaWiki extensions we're using and/or developing. Please refer to the information on the mediawiki.org wiki for installation and usage details. Extensions here which have no corresponding mediawiki article are either not ready for use or have been superseded. You can also browse our extension code in our local Subversion repository or our GitHub mirror.

1. - See http://www.mediawiki.org/Extension:Simple_Security for installation and usage details
2. - Licenced under LGPL (http://www.gnu.org/copyleft/lesser.html)
3. - Needs apache's mod-rewrite for security on images, see code comments below
4. - Version 4.0.0 started 2007-10-11

if (!defined('MEDIAWIKI')) die('Not an entry point.');

define('SIMPLESECURITY_VERSION','4.0.2, 2007-10-13');

1. Global security settings

$wgSecurityMagic = "security"; # the parser-function name for security directives $wgSecurityMagicInherit = "!security"; # the name for security directives which apply to member articles $wgSecurityMagicIf = "ifallowed"; # the name for doing a permission-based conditional $wgSecurityMagicGroup = "ifgroup"; # the name for doing a group-based conditional $wgSecuritySysops = array('sysop'); # the list of groups whose members bypass all security (groups a all lowercase, user are ucfirst) $wgSecurityDenyTemplate = 'Template:Action not permitted'; $wgSecurityDenyReadTemplate = 'Template:Not readable'; $wgSecurityInfoTemplate = 'Template:Security info'; $wgSecurityRuleTemplate = ; # set to a template for the $wgSecurityDenyImage = dirname(__FILE__).'/deny.png'; # the image returned in place of requested image if read access denied $wgNamespacePermissions = array(); $wgSecurityLogActions = array('download'); # Actions that should be logged

array_unshift($wgExtensionFunctions,'wfSetupSimpleSecurity'); $wgHooks['LanguageGetMagic'][] = 'wfSimpleSecurityLanguageGetMagic'; $wgExtensionCredits['parserhook'][] = array( 'name' => "Simple Security", 'author' => 'User:Nad', 'description' => 'A simple to implement security extension', 'url' => 'http://www.mediawiki.org/wiki/Extension:Simple_Security', 'version' => SIMPLESECURITY_VERSION );

class SimpleSecurity {

# Needed in some versions to prevent Special:Version from breaking function __toString() { return 'SimpleSecurity'; }

# Constructor function SimpleSecurity() { global $wgParser,$wgHooks,$wgLogTypes,$wgLogNames,$wgLogHeaders,$wgLogActions, $wgSecurityMagic,$wgSecurityMagicInherit,$wgSecurityMagicIf,$wgSecurityMagicGroup;

# Add all our required event hooks $wgHooks['userCan'][] = $this; $wgHooks['ArticleAfterFetchContent'][] = $this; $wgHooks['OutputPageBeforeHTML'][] = $this;

$wgParser->setFunctionHook($wgSecurityMagic,array($this,'processDirective')); $wgParser->setFunctionHook($wgSecurityMagicInherit,array($this,'processInheritDirective',SFH_NO_HASH)); $wgParser->setFunctionHook($wgSecurityMagicIf,array($this,'ifAllowed')); $wgParser->setFunctionHook($wgSecurityMagicGroup,array($this,'ifGroup'));

# Add a new log type $wgLogTypes[] = 'security'; $wgLogNames ['security'] = 'securitylogpage'; $wgLogHeaders['security'] = 'securitylogpagetext'; $wgLogActions['security/deny'] = 'securitylogentry'; }

# Process a normal security directive function processDirective(&$parser,$actions = ,$groups = ) { $parser->mOutput->mCacheTime = -1; if ($actions && $groups) $this->directives[] = array($actions,$groups); return ; }

# Process a non-inheriting security directive function processInheritDirective(&$parser,$actions = ,$groups = ) { $parser->mOutput->mCacheTime = -1; if ($actions && $groups) $this->directives[] = array($actions,$groups); return ; }

# Process the ifAllowed conditional security directive function ifAllowed(&$parser,$action,$title,$if,$else = ) { return $this->validateTitle($action,Title::newFromText($title)) ? $if : $else; }

# Process the ifGroup conditional security directive # - evaluates to true if current uset belongs to any of the groups in $groups (csv) function ifGroup(&$parser,$groups,$if,$else = ) { global $wgUser; $intersection = array_intersect( array_map('strtolower',split(',',$groups)), array_map('strtolower',$wgUser->getEffectiveGroups()) ); return count($intersection) > 0 ? $if : $else; }

# ArticleAfterFetchContent hook: Asseses security after raw content fetched from database and clears if not readable # - also fills the global $securityCache cache with info to append to the rendered article function onArticleAfterFetchContent(&$article,&$text) { global $wgSecurityDenyTemplate; $title = $article->mTitle->getText(); if (!$this->activeHooks['ArticleAfterFetchContent']) return true; if (!$this->validateTitle('view',$article->mTitle)) $text = '{'.'{'."$wgSecurityDenyTemplate|fetch|$title}}"; return true; }

# Render any security info function onOutputPageBeforeHTML(&$out,&$text) { global $wgUser,$wgTitle,$wgSecurityInfoTemplate,$wgSecurityDenyTemplate, $wgSiteNotice,$wgSecurityParseInfo,$wgSecurityRuleTemplate,$wgSecurityLogActions; static $done = 0; if ($done++) return true; $psr = new Parser; $psropt = ParserOptions::newFromUser($wgUser);

# Add rules information for this article if any $rules = $this->rules[$this->title]; if (count($rules)) {

# Construct wikitext for info $info = '{'.'{'."$wgSecurityInfoTemplate|1=\n"; foreach ($rules as $rule) { $a = $rule[0] == '*' ? 'Every action' : ucfirst($rule[0]); $b = $rule[1] == '*' ? 'anybody' : ($rule[1] == 'user' ? 'logged in' : $rule[1]); $c = isset($rule[2]) ? $rule[2] : ; if ($wgSecurityRuleTemplate) $info .= '{'.'{'."$wgSecurityRuleTemplate|$a|$b|$c}}\n"; else $info .= "*$a requires the user to be $b $c\n"; } $info .= "\n}}";

                       # Parse the wikitext (depending on $wgSecurityParseInfo) and add to SiteNotice
                       if ($wgSecurityParseInfo) {
                               $psrout = $psr->parse($info,$wgTitle,$psropt,true,true);
                               $info = $psrout->getText();
                               }

$wgSiteNotice .= $info; }

# Replace main body with deny-message and append log if action allowed if (!$this->allowed) { $text = ; $psrout = $psr->parse('{'.'{'."$wgSecurityDenyTemplate|{$this->action}|{$this->title}}}",$wgTitle,$psropt,true,true); $out->mBodytext = $psrout->getText(); if (in_array($this->action,$wgSecurityLogActions)) { $msg = wfMsgForContent('securitylogdeny',$this->action,$this->title); $log = new LogPage('security',false); $log->addEntry('deny',$wgUser->getUserPage(),$msg); } }

return true; }

# Main validation code for the whole request is done on the first call to userCan function onuserCan(&$title, &$user, $ucaction, &$result) { global $wgTitle,$action,$wgRequest,$wgUser,$wgUploadDirectory, $wgSecurityEnableForImages,$wgSecurityDenyImage,$wgSecurityLogActions;

# Add IsAllowed hook to the $wgUser object static $done = 0; if ($done++ == 0) wfSimpleSecurityAddIsAllowedHook();

# Handle security on files (needs apache mod-rewrite) # - /wiki/images/... rewritten to article title Download/image-path... if (ereg('^Download/(.+)/([^/]+)$',$this->title,$match)) { $this->path = $match[1]; $this->file = $image = $match[2]; if (ereg('^thumb/.+/([^/]+)$',$this->path,$match)) $image = $match[1]; $wgTitle = Title::newFromText($this->title = "Image:$image"); $action = 'raw'; }

# If the requested item is a file, return it to the client if security validates otherwise return the SecurityDenyImage if ($wgSecurityEnableForImages && $this->file) { if (in_array('download',$wgSecurityLogActions)) { $msg = wfMsgForContent('securitylogdeny','download',$this->title); $log = new LogPage('security',false); $log->addEntry('deny',$wgUser->getUserPage(),$msg); } $pathname = $this->allowed ? "$wgUploadDirectory/".$this->path.'/'.$this->file : $wgSecurityDenyImage; while (@ob_end_clean()); header('Content-Type: application/octet-stream'); header('Content-Disposition: attachment; filename="'.$this->file.'"'); $content = implode(,file($pathname)); if (in_array('Content-Encoding: gzip',headers_list())) $content = gzencode($content); echo($content); die; }

return true; }

# Validate the passed database row and replace any invalidate content function validateDatabaseRow(&$row) { global $wgUser,$wgSecuritySysops,$wgSecurityDenyReadTemplate; }

# Validate the passed action against the current user and title function validateAction(&$user,$action) { global $wgSecuritySysops; }

}

1. Add IsAllowed hook to the $wgUser object

function wfSimpleSecurityAddIsAllowedHook() { global $wgUser;

# Create a new User class ($User2) by extending the existing one with an overridden isAllowed method $User = get_class($wgUser); $User2 = $User.'2'; eval("class $User2 extends $User".' { function isAllowed($action = "") { global $wgSimpleSecurity; $result = $wgSimpleSecurity->validateAction($this,$action); return $result === NULL ? $result = parent::isAllowed($action) : $result; } }');

# Replace the $wgUser object with an identical $User2 instance $oldUser = $wgUser; $wgUser = new $User2(); foreach (array_keys(get_class_vars($User)) as $k) $wgUser->$k = $oldUser->$k; }

1. Add DatabaseFetch and DatabaseQuery hooks

function wfSimpleSecurityAddDatabaseHooks() { global $wgLoadBalancer,$wgDBtype;

wfGetDB(); # This ensures that $wgLoadBalancer is not a stub object when we subclass it

# Create a replica of the Database class # - query method is overriden to ensure that old_id field is returned for all queries which read old_text field # - fetchObject method is overridden to validate row content based on old_id $type = ucfirst($wgDBtype); eval("class Database{$type}2 extends Database{$type}".' {

public function query($sql,$fname = "",$tempIgnore = false) { $sql = preg_replace_callback("/(?<=SELECT ).+?(?= FROM)/","wfSimpleSecurityPatchSQL",$sql,1); return parent::query($sql,$fname,$tempIgnore); }

function fetchObject(&$res) { global $wgSimpleSecurity; $row = parent::fetchObject($res); $wgSimpleSecurity->validateDatabaseRow($row); return $row; }

}');

# Create a replica of the LoadBalancer class which uses the new Database subclass for its connection objects $LoadBalancer = get_class($wgLoadBalancer); $LoadBalancer2 = $LoadBalancer."2"; eval("class $LoadBalancer2 extends $LoadBalancer".' {

function reallyOpenConnection(&$server) { $server["type"] .= "2"; $db =& parent::reallyOpenConnection($server); return $db; } }');

# Replace the $wgLoadBalancer object with an identical instance of the new LoadBalancer2 class $wgLoadBalancer->closeAll(); # Close any open connections as they will be of the original Database class $oldLoadBalancer = $wgLoadBalancer; $wgLoadBalancer = new $LoadBalancer2($oldLoadBalancer->mServers); foreach (array_keys(get_class_vars($LoadBalancer)) as $k) $wgLoadBalancer->$k = $oldLoadBalancer->$k;

}

1. Patches SQL queries to ensure that the old_id field is present in all requests for the old_text field so permissions can be validated

function wfSimpleSecurityPatchSQL($match) { if (!preg_match("/old_text/",$match[0])) return $match[0]; $fields = str_replace(" ","",$match[0]); return ($fields == "*" || preg_match("/old_id/",$fields)) ? $fields : "$fields,old_id"; }

1. Called from $wgExtensionFunctions array when initialising extensions

function wfSetupSimpleSecurity() { global $wgSimpleSecurity,$wgLanguageCode,$wgMessageCache;

wfSimpleSecurityAddDatabaseHooks();

$wgSimpleSecurity = new SimpleSecurity();

# Add the messages used by the specialpage if ($wgLanguageCode == 'en') { $wgMessageCache->addMessages(array( 'security' => "Security log", 'securitylogpage' => "Security log", 'securitylogpagetext' => "This is a log of actions blocked by the SimpleSecurity extension.", 'securitylogdeny' => "Attempt to $1 $2 was denied.", 'securitylogentry' => "" )); }

}

1. Needed in MediaWiki >1.8.0 for magic word hooks to work properly

function wfSimpleSecurityLanguageGetMagic(&$magicWords,$langCode = 0) { global $wgSecurityMagic,$wgSecurityMagicInherit,$wgSecurityMagicIf,$wgSecurityMagicGroup; $magicWords[$wgSecurityMagic] = array(0,$wgSecurityMagic); $magicWords[$wgSecurityMagicInherit] = array(0,$wgSecurityMagicInherit); $magicWords[$wgSecurityMagicIf] = array(0,$wgSecurityMagicIf); $magicWords[$wgSecurityMagicGroup] = array(0,$wgSecurityMagicGroup); return true; } ?>