171 lines
		
	
	
	
		
			7.4 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
			
		
		
	
	
			171 lines
		
	
	
	
		
			7.4 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
| <?php
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| 
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| /**
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|  * Removes all unrecognized tags from the list of tokens.
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|  *
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|  * This strategy iterates through all the tokens and removes unrecognized
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|  * tokens. If a token is not recognized but a TagTransform is defined for
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|  * that element, the element will be transformed accordingly.
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|  */
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| 
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| class HTMLPurifier_Strategy_RemoveForeignElements extends HTMLPurifier_Strategy
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| {
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| 
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|     public function execute($tokens, $config, $context) {
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|         $definition = $config->getHTMLDefinition();
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|         $generator = new HTMLPurifier_Generator($config, $context);
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|         $result = array();
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| 
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|         $escape_invalid_tags = $config->get('Core.EscapeInvalidTags');
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|         $remove_invalid_img  = $config->get('Core.RemoveInvalidImg');
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| 
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|         // currently only used to determine if comments should be kept
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|         $trusted = $config->get('HTML.Trusted');
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| 
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|         $remove_script_contents = $config->get('Core.RemoveScriptContents');
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|         $hidden_elements     = $config->get('Core.HiddenElements');
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| 
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|         // remove script contents compatibility
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|         if ($remove_script_contents === true) {
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|             $hidden_elements['script'] = true;
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|         } elseif ($remove_script_contents === false && isset($hidden_elements['script'])) {
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|             unset($hidden_elements['script']);
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|         }
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| 
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|         $attr_validator = new HTMLPurifier_AttrValidator();
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| 
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|         // removes tokens until it reaches a closing tag with its value
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|         $remove_until = false;
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| 
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|         // converts comments into text tokens when this is equal to a tag name
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|         $textify_comments = false;
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| 
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|         $token = false;
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|         $context->register('CurrentToken', $token);
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| 
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|         $e = false;
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|         if ($config->get('Core.CollectErrors')) {
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|             $e =& $context->get('ErrorCollector');
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|         }
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| 
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|         foreach($tokens as $token) {
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|             if ($remove_until) {
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|                 if (empty($token->is_tag) || $token->name !== $remove_until) {
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|                     continue;
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|                 }
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|             }
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|             if (!empty( $token->is_tag )) {
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|                 // DEFINITION CALL
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| 
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|                 // before any processing, try to transform the element
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|                 if (
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|                     isset($definition->info_tag_transform[$token->name])
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|                 ) {
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|                     $original_name = $token->name;
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|                     // there is a transformation for this tag
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|                     // DEFINITION CALL
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|                     $token = $definition->
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|                                 info_tag_transform[$token->name]->
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|                                     transform($token, $config, $context);
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|                     if ($e) $e->send(E_NOTICE, 'Strategy_RemoveForeignElements: Tag transform', $original_name);
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|                 }
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| 
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|                 if (isset($definition->info[$token->name])) {
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| 
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|                     // mostly everything's good, but
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|                     // we need to make sure required attributes are in order
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|                     if (
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|                         ($token instanceof HTMLPurifier_Token_Start || $token instanceof HTMLPurifier_Token_Empty) &&
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|                         $definition->info[$token->name]->required_attr &&
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|                         ($token->name != 'img' || $remove_invalid_img) // ensure config option still works
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|                     ) {
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|                         $attr_validator->validateToken($token, $config, $context);
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|                         $ok = true;
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|                         foreach ($definition->info[$token->name]->required_attr as $name) {
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|                             if (!isset($token->attr[$name])) {
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|                                 $ok = false;
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|                                 break;
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|                             }
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|                         }
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|                         if (!$ok) {
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|                             if ($e) $e->send(E_ERROR, 'Strategy_RemoveForeignElements: Missing required attribute', $name);
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|                             continue;
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|                         }
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|                         $token->armor['ValidateAttributes'] = true;
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|                     }
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| 
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|                     if (isset($hidden_elements[$token->name]) && $token instanceof HTMLPurifier_Token_Start) {
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|                         $textify_comments = $token->name;
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|                     } elseif ($token->name === $textify_comments && $token instanceof HTMLPurifier_Token_End) {
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|                         $textify_comments = false;
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|                     }
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| 
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|                 } elseif ($escape_invalid_tags) {
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|                     // invalid tag, generate HTML representation and insert in
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|                     if ($e) $e->send(E_WARNING, 'Strategy_RemoveForeignElements: Foreign element to text');
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|                     $token = new HTMLPurifier_Token_Text(
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|                         $generator->generateFromToken($token)
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|                     );
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|                 } else {
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|                     // check if we need to destroy all of the tag's children
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|                     // CAN BE GENERICIZED
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|                     if (isset($hidden_elements[$token->name])) {
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|                         if ($token instanceof HTMLPurifier_Token_Start) {
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|                             $remove_until = $token->name;
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|                         } elseif ($token instanceof HTMLPurifier_Token_Empty) {
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|                             // do nothing: we're still looking
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|                         } else {
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|                             $remove_until = false;
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|                         }
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|                         if ($e) $e->send(E_ERROR, 'Strategy_RemoveForeignElements: Foreign meta element removed');
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|                     } else {
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|                         if ($e) $e->send(E_ERROR, 'Strategy_RemoveForeignElements: Foreign element removed');
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|                     }
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|                     continue;
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|                 }
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|             } elseif ($token instanceof HTMLPurifier_Token_Comment) {
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|                 // textify comments in script tags when they are allowed
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|                 if ($textify_comments !== false) {
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|                     $data = $token->data;
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|                     $token = new HTMLPurifier_Token_Text($data);
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|                 } elseif ($trusted) {
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|                     // keep, but perform comment cleaning
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|                     if ($e) {
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|                         // perform check whether or not there's a trailing hyphen
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|                         if (substr($token->data, -1) == '-') {
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|                             $e->send(E_NOTICE, 'Strategy_RemoveForeignElements: Trailing hyphen in comment removed');
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|                         }
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|                     }
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|                     $token->data = rtrim($token->data, '-');
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|                     $found_double_hyphen = false;
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|                     while (strpos($token->data, '--') !== false) {
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|                         if ($e && !$found_double_hyphen) {
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|                             $e->send(E_NOTICE, 'Strategy_RemoveForeignElements: Hyphens in comment collapsed');
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|                         }
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|                         $found_double_hyphen = true; // prevent double-erroring
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|                         $token->data = str_replace('--', '-', $token->data);
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|                     }
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|                 } else {
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|                     // strip comments
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|                     if ($e) $e->send(E_NOTICE, 'Strategy_RemoveForeignElements: Comment removed');
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|                     continue;
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|                 }
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|             } elseif ($token instanceof HTMLPurifier_Token_Text) {
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|             } else {
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|                 continue;
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|             }
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|             $result[] = $token;
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|         }
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|         if ($remove_until && $e) {
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|             // we removed tokens until the end, throw error
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|             $e->send(E_ERROR, 'Strategy_RemoveForeignElements: Token removed to end', $remove_until);
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|         }
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| 
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|         $context->destroy('CurrentToken');
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| 
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|         return $result;
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|     }
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| 
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| }
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| 
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| // vim: et sw=4 sts=4
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