- Author:
- David Nickerson <david.nickerson@gmail.com>
- Date:
- 2021-09-17 15:50:49+12:00
- Desc:
- tweak html formatting
- Permanent Source URI:
- https://models.fieldml.org/workspace/a1/rawfile/1b3862589abf79ae9119ee0b5e99a8b785d762e1/dojo-presentation/js/dojo/dojox/secure/DOM.js
dojo.provide("dojox.secure.DOM");
dojo.require("dojox.lang.observable");
dojox.secure.DOM = function(element){
function safeNode(node){
if(!node){
return node;
}
var parent = node;
do {
if(parent == element){
return wrap(node);
}
} while((parent = parent.parentNode));
return null;
}
function wrap(result){
if(result){
if(result.nodeType){
// wrap the node
var wrapped = nodeObserver(result);
if(result.nodeType == 1 && typeof wrapped.style == 'function'){ // if it is a function, that means it is holding a slot for us, now we will override it
wrapped.style = styleObserver(result.style);
wrapped.ownerDocument = safeDoc;
wrapped.childNodes = {__get__:function(i){
return wrap(result.childNodes[i]);
},
length:0
};
//TODO: maybe add attributes
}
return wrapped;
}
if(result && typeof result == 'object'){
if(result.__observable){
// we have already wrapped it, this helps prevent circular/infinite loops
return result.__observable;
}
// wrap the node list
wrapped = result instanceof Array ? [] : {};
result.__observable = wrapped;
for(var i in result){
if (i != '__observable'){
wrapped[i] = wrap(result[i]);
}
}
wrapped.data__ = result;
return wrapped;
}
if(typeof result == 'function'){
var unwrap = function(result){
if(typeof result == 'function'){
// if untrusted code passes a function to trusted code, we want the trusted code to be
// able to execute it and have the arguments automatically wrapped
return function(){
for (var i = 0; i < arguments.length; i++){
arguments[i] = wrap(arguments[i]);
}
return unwrap(result.apply(wrap(this),arguments));
}
}
return dojox.secure.unwrap(result);
};
// when we wrap a function we make it so that we can untrusted code can execute
// the function and the arguments will be unwrapped for the trusted code
return function(){
if(result.safetyCheck){
result.safetyCheck.apply(unwrap(this),arguments);
}
for (var i = 0; i < arguments.length; i++){
arguments[i] = unwrap(arguments[i]);
}
return wrap(result.apply(unwrap(this),arguments));
}
}
}
return result;
}
unwrap = dojox.secure.unwrap;
function safeCSS(css){
css += ''; // make sure it is a string
if(css.match(/behavior:|content:|javascript:|binding|expression|\@import/)){
throw new Error("Illegal CSS");
}
var id = element.id || (element.id = "safe" + ('' + Math.random()).substring(2));
return css.replace(/(\}|^)\s*([^\{]*\{)/g,function(t,a,b){ // put all the styles in the context of the id of the sandbox
return a + ' #' + id + ' ' + b; // need to remove body and html references something like: .replace(/body/g,''); but that would break mybody...
});
}
function safeURL(url){
// test a url to see if it is safe
if(url.match(/:/) && !url.match(/^(http|ftp|mailto)/)){
throw new Error("Unsafe URL " + url);
}
}
function safeElement(el){
// test an element to see if it is safe
if(el && el.nodeType == 1){
if(el.tagName.match(/script/i)){
var src = el.src;
if (src && src != ""){
// load the src and evaluate it safely
el.parentNode.removeChild(el);
dojo.xhrGet({url:src,secure:true}).addCallback(function(result){
safeDoc.evaluate(result);
});
}
else{
//evaluate the script safely and remove it
var script = el.innerHTML;
el.parentNode.removeChild(el);
wrap.evaluate(script);
}
}
if(el.tagName.match(/link/i)){
throw new Error("illegal tag");
}
if(el.tagName.match(/style/i)){
var setCSS = function(cssStr){
if(el.styleSheet){// IE
el.styleSheet.cssText = cssStr;
} else {// w3c
var cssText = doc.createTextNode(cssStr);
if (el.childNodes[0])
el.replaceChild(cssText,el.childNodes[0])
else
el.appendChild(cssText);
}
}
src = el.src;
if(src && src != ""){
alert('src' + src);
// try to load it by url and safely load it
el.src = null;
dojo.xhrGet({url:src,secure:true}).addCallback(function(result){
setCSS(safeCSS(result));
});
}
setCSS(safeCSS(el.innerHTML));
}
if(el.style){
safeCSS(el.style.cssText);
}
if(el.href){
safeURL(el.href);
}
if(el.src){
safeURL(el.src);
}
var attr,i = 0;
while ((attr=el.attributes[i++])){
if(attr.name.substring(0,2)== "on" && attr.value != "null" && attr.value != ""){ // must remove all the event handlers
throw new Error("event handlers not allowed in the HTML, they must be set with element.addEventListener");
}
}
var children = el.childNodes;
for (i =0, l = children.length; i < l; i++){
safeElement(children[i]);
}
}
}
function safeHTML(html){
var div = document.createElement("div");
div.innerHTML = html; // this is safe with an unattached node
safeElement(div);
return div;
}
var doc = element.ownerDocument;
var safeDoc = {
getElementById : function(id){
return safeNode(doc.getElementById(id));
},
createElement : function(name){
return wrap(doc.createElement(name));
},
createTextNode : function(name){
return wrap(doc.createTextNode(name));
},
write : function(str){
var div = safeHTML(str);
while (div.childNodes.length){
// move all these children to the main node
element.appendChild(div.childNodes[0]);
}
}
};
safeDoc.open = safeDoc.close = function(){}; // no-op functions
var setters = {
innerHTML : function(node,value){
console.log('setting innerHTML');
node.innerHTML = safeHTML(value).innerHTML;
}
};
setters.outerHTML = function(node,value){
throw new Error("Can not set this property");
}; // blocked
function domChanger(name,newNodeArg){
return function(node,args){
safeElement(args[newNodeArg]); // check to make sure the new node is safe
return node[name](args[0]);// execute the method
};
}
var invokers = {
appendChild : domChanger("appendChild",0),
insertBefore : domChanger("insertBefore",0),
replaceChild : domChanger("replaceChild",1),
cloneNode : function(node,args){
return node.cloneNode(args[0]);
},
addEventListener : function(node,args){
dojo.connect(node,'on' + args[0],this,function(event){
event = nodeObserver(event || window.event);
args[1].call(this,event);
});
}
};
invokers.childNodes = invokers.style = invokers.ownerDocument = function(){}; // this is a trick to get these property slots available, they will be overridden
function makeObserver(setter){ // we make two of these, but the setter for style nodes is different
return dojox.lang.makeObservable(
function(node, prop){
var result;
return node[prop];
},setter,
function(wrapper, node, methodName, args){
for (var i = 0; i < args.length; i++){
args[i] = unwrap(args[i]);
}
if(invokers[methodName]){
return wrap(invokers[methodName].call(wrapper,node,args));
}
return wrap(node[methodName].apply(node,args));
},invokers);
}
var nodeObserver = makeObserver(function(node, prop, value){
if(setters[prop]){
setters[prop](node,value);
}
node[prop] = value;
});
var blockedStyles = {behavior:1,MozBinding:1};
var styleObserver = makeObserver(function(node, prop, value){
if(!blockedStyles[prop]){
node[prop] = safeCSS(value);
}
});
wrap.safeHTML = safeHTML;
wrap.safeCSS = safeCSS;
return wrap;
};
dojox.secure.unwrap = function unwrap(result){
return (result && result.data__) || result;
};
