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htmlpurifier/library/HTMLPurifier/HTMLModuleManager.php
2007-04-30 21:19:15 +00:00

576 lines
22 KiB
PHP

<?php
require_once 'HTMLPurifier/HTMLModule.php';
require_once 'HTMLPurifier/ElementDef.php';
require_once 'HTMLPurifier/ContentSets.php';
require_once 'HTMLPurifier/AttrTypes.php';
require_once 'HTMLPurifier/AttrCollections.php';
require_once 'HTMLPurifier/AttrDef.php';
require_once 'HTMLPurifier/AttrDef/Enum.php';
// W3C modules
require_once 'HTMLPurifier/HTMLModule/CommonAttributes.php';
require_once 'HTMLPurifier/HTMLModule/Text.php';
require_once 'HTMLPurifier/HTMLModule/Hypertext.php';
require_once 'HTMLPurifier/HTMLModule/List.php';
require_once 'HTMLPurifier/HTMLModule/Presentation.php';
require_once 'HTMLPurifier/HTMLModule/Edit.php';
require_once 'HTMLPurifier/HTMLModule/Bdo.php';
require_once 'HTMLPurifier/HTMLModule/Tables.php';
require_once 'HTMLPurifier/HTMLModule/Image.php';
require_once 'HTMLPurifier/HTMLModule/StyleAttribute.php';
require_once 'HTMLPurifier/HTMLModule/Legacy.php';
require_once 'HTMLPurifier/HTMLModule/Target.php';
// proprietary modules
require_once 'HTMLPurifier/HTMLModule/TransformToStrict.php';
require_once 'HTMLPurifier/HTMLModule/TransformToXHTML11.php';
HTMLPurifier_ConfigSchema::define(
'HTML', 'Doctype', null, 'string/null',
'Doctype to use, valid values are HTML 4.01 Transitional, HTML 4.01 '.
'Strict, XHTML 1.0 Transitional, XHTML 1.0 Strict, XHTML 1.1. '.
'Technically speaking this is not actually a doctype (as it does '.
'not identify a corresponding DTD), but we are using this name '.
'for sake of simplicity. This will override any older directives '.
'like %Core.XHTML or %HTML.Strict.'
);
class HTMLPurifier_HTMLModuleManager
{
/**
* Array of HTMLPurifier_Module instances, indexed by module's class name.
* All known modules, regardless of use, are in this array.
*/
var $modules = array();
/**
* String doctype we will validate against. See $validModules for use.
*
* @note
* There is a special doctype '*' that acts both as the "default"
* doctype if a customized system only defines one doctype and
* also a catch-all doctype that gets merged into all the other
* module collections. When possible, use a private collection to
* share modules between doctypes: this special doctype is to
* make life more convenient for users.
*/
var $doctype;
var $doctypeAliases = array(); /**< Lookup array of strings to real doctypes */
/**
* Associative array: $collections[$type][$doctype] = list of modules.
* This is used to logically separate types of functionality so that
* based on the doctype and other configuration settings they may
* be easily switched and on and off. Custom setups may not need
* to use this abstraction, opting to have only one big collection
* with one valid doctype.
*/
var $collections = array();
/**
* Modules that may be used in a valid doctype of this kind.
* Correctional and leniency modules should not be placed in this
* array unless the user said so: don't stuff every possible lenient
* module for this doctype in here.
*/
var $validModules = array();
var $validCollections = array(); /**< Collections to merge into $validModules */
/**
* Modules that we will allow in input, subset of $validModules. Single
* element definitions may result in us consulting validModules.
*/
var $activeModules = array();
var $activeCollections = array(); /**< Collections to merge into $activeModules */
var $counter = 0; /**< Designates next available integer order for modules. */
var $initialized = false; /**< Says whether initialize() was called */
/**
* Specifies what doctype to siphon new modules from addModule() to,
* or false to disable the functionality. Must be used in conjunction
* with $autoCollection.
*/
var $autoDoctype = false;
/**
* Specifies what collection to siphon new modules from addModule() to,
* or false to disable the functionality. Must be used in conjunction
* with $autoCollection.
*/
var $autoCollection = false;
/** Associative array of element name to defining modules (always array) */
var $elementLookup = array();
/** List of prefixes we should use for resolving small names */
var $prefixes = array('HTMLPurifier_HTMLModule_');
var $contentSets; /**< Instance of HTMLPurifier_ContentSets */
var $attrTypes; /**< Instance of HTMLPurifier_AttrTypes */
var $attrCollections; /**< Instance of HTMLPurifier_AttrCollections */
/**
* @param $blank If true, don't do any initializing
*/
function HTMLPurifier_HTMLModuleManager($blank = false) {
// the only editable internal object. The rest need to
// be manipulated through modules
$this->attrTypes = new HTMLPurifier_AttrTypes();
if (!$blank) $this->initialize();
}
function initialize() {
$this->initialized = true;
// load default modules to the recognized modules list (not active)
$modules = array(
// define
'CommonAttributes',
'Text', 'Hypertext', 'List', 'Presentation',
'Edit', 'Bdo', 'Tables', 'Image', 'StyleAttribute',
'Target',
// define-redefine
'Legacy',
// redefine
'TransformToStrict', 'TransformToXHTML11'
);
foreach ($modules as $module) {
$this->addModule($module);
}
// Safe modules for supported doctypes. These are included
// in the valid and active module lists by default
$this->collections['Safe'] = array(
'_Common' => array( // leading _ indicates private
'CommonAttributes', 'Text', 'Hypertext', 'List',
'Presentation', 'Edit', 'Bdo', 'Tables', 'Image',
'StyleAttribute'
),
// HTML definitions, defer to XHTML definitions
'HTML 4.01 Transitional' => array(array('XHTML 1.0 Transitional')),
'HTML 4.01 Strict' => array(array('XHTML 1.0 Strict')),
// XHTML definitions
'XHTML 1.0 Transitional' => array( array('XHTML 1.0 Strict'), 'Legacy', 'Target' ),
'XHTML 1.0 Strict' => array(array('_Common')),
'XHTML 1.1' => array(array('_Common')),
);
// Modules that specify elements that are unsafe from untrusted
// third-parties. These should be registered in $validModules but
// almost never $activeModules unless you really know what you're
// doing.
$this->collections['Unsafe'] = array();
// Modules to import if lenient mode (attempt to convert everything
// to a valid representation) is on. These must not be in $validModules
// unless specified so.
$this->collections['Lenient'] = array(
'HTML 4.01 Strict' => array(array('XHTML 1.0 Strict')),
'XHTML 1.0 Strict' => array('TransformToStrict'),
'XHTML 1.1' => array(array('XHTML 1.0 Strict'), 'TransformToXHTML11')
);
// Modules to import if correctional mode (correct everything that
// is feasible to strict mode) is on. These must not be in $validModules
// unless specified so.
$this->collections['Correctional'] = array(
'HTML 4.01 Transitional' => array(array('XHTML 1.0 Transitional')),
'XHTML 1.0 Transitional' => array('TransformToStrict'), // probably want a different one
);
// User-space modules, custom code or whatever
$this->collections['Extension'] = array();
// setup active versus valid modules. ORDER IS IMPORTANT!
// definition modules
$this->makeCollectionActive('Safe');
$this->makeCollectionValid('Unsafe');
// redefinition modules
$this->makeCollectionActive('Lenient');
$this->makeCollectionActive('Correctional');
$this->autoDoctype = '*';
$this->autoCollection = 'Extension';
}
/**
* Adds a module to the recognized module list. This does not
* do anything else: the module must be added to a corresponding
* collection to be "activated".
* @param $module Mixed: string module name, with or without
* HTMLPurifier_HTMLModule prefix, or instance of
* subclass of HTMLPurifier_HTMLModule.
* @note This function will not call autoload, you must instantiate
* (and thus invoke) autoload outside the method.
* @note If a string is passed as a module name, different variants
* will be tested in this order:
* - Check for HTMLPurifier_HTMLModule_$name
* - Check all prefixes with $name in order they were added
* - Check for literal object name
* - Throw fatal error
* If your object name collides with an internal class, specify
* your module manually.
*/
function addModule($module) {
if (is_string($module)) {
$original_module = $module;
$ok = false;
foreach ($this->prefixes as $prefix) {
$module = $prefix . $original_module;
if (class_exists($module)) {
$ok = true;
break;
}
}
if (!$ok) {
$module = $original_module;
if (!class_exists($module, false)) {
trigger_error($original_module . ' module does not exist',
E_USER_ERROR);
return;
}
}
$module = new $module();
}
$module->order = $this->counter++; // assign then increment
$this->modules[$module->name] = $module;
if ($this->autoDoctype !== false && $this->autoCollection !== false) {
$this->collections[$this->autoCollection][$this->autoDoctype][] = $module->name;
}
}
/**
* Makes a collection active, while also making it valid if not
* already done so. See $activeModules for the semantics of "active".
* @param $collection_name Name of collection to activate
*/
function makeCollectionActive($collection_name) {
if (!in_array($collection_name, $this->validCollections)) {
$this->makeCollectionValid($collection_name);
}
$this->activeCollections[] = $collection_name;
}
/**
* Makes a collection valid. See $validModules for the semantics of "valid"
*/
function makeCollectionValid($collection_name) {
$this->validCollections[] = $collection_name;
}
/**
* Adds a class prefix that addModule() will use to resolve a
* string name to a concrete class
*/
function addPrefix($prefix) {
$this->prefixes[] = (string) $prefix;
}
function setup($config) {
// load up the autocollection
if ($this->autoCollection !== false) {
$this->makeCollectionActive($this->autoCollection);
}
// retrieve the doctype
$this->doctype = $this->getDoctype($config);
if (isset($this->doctypeAliases[$this->doctype])) {
$this->doctype = $this->doctypeAliases[$this->doctype];
}
// process module collections to module name => module instance form
foreach ($this->collections as $col_i => $x) {
$this->processCollections($this->collections[$col_i]);
}
$this->validModules = $this->assembleModules($this->validCollections);
$this->activeModules = $this->assembleModules($this->activeCollections);
// setup lookup table based on all valid modules
foreach ($this->validModules as $module) {
foreach ($module->info as $name => $def) {
if (!isset($this->elementLookup[$name])) {
$this->elementLookup[$name] = array();
}
$this->elementLookup[$name][] = $module->name;
}
}
// note the different choice
$this->contentSets = new HTMLPurifier_ContentSets(
// content models that contain non-allowed elements are
// harmless because RemoveForeignElements will ensure
// they never get in anyway, and there is usually no
// reason why you should want to restrict a content
// model beyond what is mandated by the doctype.
// Note, however, that this means redefinitions of
// content models can't be tossed in validModels willy-nilly:
// that stuff still is regulated by configuration.
$this->validModules
);
$this->attrCollections = new HTMLPurifier_AttrCollections(
$this->attrTypes,
// only explicitly allowed modules are allowed to affect
// the global attribute collections. This mean's there's
// a distinction between loading the Bdo module, and the
// bdo element: Bdo will enable the dir attribute on all
// elements, while bdo will only define the bdo element,
// which will not have an editable directionality. This might
// catch people who are loading only elements by surprise, so
// we should consider loading an entire module if all the
// elements it defines are requested by the user, especially
// if it affects the global attribute collections.
$this->activeModules
);
}
/**
* Takes a list of collections and merges together all the defined
* modules for the current doctype from those collections.
* @param $collections List of collection suffixes we should grab
* modules from (like 'Safe' or 'Lenient')
*/
function assembleModules($collections) {
$modules = array();
$numOfCollectionsUsed = 0;
foreach ($collections as $name) {
$disable_global = false;
if (!isset($this->collections[$name])) {
trigger_error("$name collection is undefined", E_USER_ERROR);
continue;
}
$cols = $this->collections[$name];
if (isset($cols[$this->doctype])) {
if (isset($cols[$this->doctype]['*'])) {
unset($cols[$this->doctype]['*']);
$disable_global = true;
}
$modules += $cols[$this->doctype];
$numOfCollectionsUsed++;
}
// accept catch-all doctype
if (
$this->doctype !== '*' &&
isset($cols['*']) &&
!$disable_global
) {
$modules += $cols['*'];
}
}
if ($numOfCollectionsUsed < 1) {
// possible XSS injection if user-specified doctypes
// are allowed
trigger_error("Doctype {$this->doctype} does not exist, ".
"check for typos (if you desire a doctype that allows ".
"no elements, use an empty array collection)", E_USER_ERROR);
}
return $modules;
}
/**
* Takes a collection and performs inclusions and substitutions for it.
* @param $cols Reference to collections class member variable
*/
function processCollections(&$cols) {
// $cols is the set of collections
// $col_i is the name (index) of a collection
// $col is a collection/list of modules
// perform inclusions
foreach ($cols as $col_i => $col) {
$seen = array();
if (!empty($col[0]) && is_array($col[0])) {
$seen[$col_i] = true; // recursion reporting
$includes = $col[0];
unset($cols[$col_i][0]); // remove inclusions value, recursion guard
} else {
$includes = array();
}
if (empty($includes)) continue;
for ($i = 0; isset($includes[$i]); $i++) {
$inc = $includes[$i];
if (isset($seen[$inc])) {
trigger_error(
"Circular inclusion detected in $col_i collection",
E_USER_ERROR
);
continue;
} else {
$seen[$inc] = true;
}
if (!isset($cols[$inc])) {
trigger_error(
"Collection $col_i tried to include undefined ".
"collection $inc", E_USER_ERROR);
continue;
}
foreach ($cols[$inc] as $module) {
if (is_array($module)) { // another inclusion!
foreach ($module as $inc2) $includes[] = $inc2;
continue;
}
$cols[$col_i][] = $module; // merge in the other modules
}
}
}
// replace with real modules, invert module from list to
// assoc array of module name to module instance
foreach ($cols as $col_i => $col) {
$ignore_global = false;
$order = array();
foreach ($col as $module_i => $module) {
unset($cols[$col_i][$module_i]);
if (is_array($module)) {
trigger_error("Illegal inclusion array at index".
" $module_i found collection $col_i, inclusion".
" arrays must be at start of collection (index 0)",
E_USER_ERROR);
continue;
}
if ($module_i === '*' && $module === false) {
$ignore_global = true;
continue;
}
if (!isset($this->modules[$module])) {
trigger_error(
"Collection $col_i references undefined ".
"module $module",
E_USER_ERROR
);
continue;
}
$module = $this->modules[$module];
$cols[$col_i][$module->name] = $module;
$order[$module->name] = $module->order;
}
array_multisort(
$order, SORT_ASC, SORT_NUMERIC, $cols[$col_i]
);
if ($ignore_global) $cols[$col_i]['*'] = false;
}
// delete pseudo-collections
foreach ($cols as $col_i => $col) {
if ($col_i[0] == '_') unset($cols[$col_i]);
}
}
/**
* Retrieves the doctype from the configuration object
*/
function getDoctype($config) {
$doctype = $config->get('HTML', 'Doctype');
if ($doctype !== null) {
return $doctype;
}
if (!$this->initialized) {
// don't do HTML-oriented backwards compatibility stuff
// use either the auto-doctype, or the catch-all doctype
return $this->autoDoctype ? $this->autoDoctype : '*';
}
// this is backwards-compatibility stuff
if ($config->get('Core', 'XHTML')) {
$doctype = 'XHTML 1.0';
} else {
$doctype = 'HTML 4.01';
}
if ($config->get('HTML', 'Strict')) {
$doctype .= ' Strict';
} else {
$doctype .= ' Transitional';
}
return $doctype;
}
/**
* Retrieves merged element definitions for all active elements.
* @note We may want to generate an elements array during setup
* and pass that on, because a specific combination of
* elements may trigger the loading of a module.
* @param $config Instance of HTMLPurifier_Config, for determining
* stray elements.
*/
function getElements($config) {
$elements = array();
foreach ($this->activeModules as $module) {
foreach ($module->elements as $name) {
$elements[$name] = $this->getElement($name, $config);
}
}
// standalone elements now loaded
return $elements;
}
/**
* Retrieves a single merged element definition
* @param $name Name of element
* @param $config Instance of HTMLPurifier_Config, may not be necessary.
*/
function getElement($name, $config) {
$def = false;
$modules = $this->validModules;
if (!isset($this->elementLookup[$name])) {
return false;
}
foreach($this->elementLookup[$name] as $module_name) {
$module = $modules[$module_name];
$new_def = $module->info[$name];
if (!$def && $new_def->standalone) {
$def = $new_def;
} elseif ($def) {
$def->mergeIn($new_def);
} else {
// could "save it for another day":
// non-standalone definitions that don't have a standalone
// to merge into could be deferred to the end
continue;
}
// attribute value expansions
$this->attrCollections->performInclusions($def->attr);
$this->attrCollections->expandIdentifiers($def->attr, $this->attrTypes);
// descendants_are_inline, for ChildDef_Chameleon
if (is_string($def->content_model) &&
strpos($def->content_model, 'Inline') !== false) {
if ($name != 'del' && $name != 'ins') {
// this is for you, ins/del
$def->descendants_are_inline = true;
}
}
$this->contentSets->generateChildDef($def, $module);
}
return $def;
}
}
?>