Prevent AngularJS interpolation in certain DOM hierarchies - ruby-on-rails

I use AngularJS and have some parts of HTML that I don't wish to interpolate because it contains user inputted data. So potentially the data may have {{asdf}} in there that I don't want AngularJS to parse. This is because if the user inputs {{{}, {}} this may break the compilation process and prevent any Angular code from running.
Is there a way around this by specifying to Angular not to compile this part of the DOM tree?

The Non Bindable directive I believe is what your looking for.
So at any element you can do:
<div ng-non-bindable> Some {{1+2}} expressions</div>
That will display:
Some {{1+2}} expressions

Related

ASP.NET MVC XSS protection

According to OWASP XSS page, one needs to use different XSS protection techniques for different contexts. However, in ASP.NET MVC Razor views, we only have the # sign to escape data in the context of HTML element inner content. What about HTML attributes, CSS, javascript contexts and others?
HTML element content
This is safe and will work as expected:
<div>#data</data>
HTML element attribute
This is not safe and can be exploited:
<div style="background: #color"></div>
JavaScript
While this is not safe:
<script>
var value = #value;
</script>
Safe solution is:
<script>
var value = #Json.Encode(value);
</script>
CSS
This is not safe and can be exploited:
<style>
.box { background : #color; }
</style>
A great thing about razor is that it does all the HTML encoding by default. Unless you use #Html.Raw(), it is pretty difficult to make your page vulnerable. You generally have to explicitly make variables render as html.
You also have Html.Encode() if you need it. There is also HttpUtility.JavaScriptStringEncode()
Regarding the updated vulnerable code:
#{var js = "alert(1);";}
<script>var value = #js</script>
I think you would be violating rule 0 with this code. You are inserting arbitrary strings into a script tag, and expecting it not to be executed. I actually get a syntax error (warning) with your example, but it will still run. If you wrapped it in quotes, you would be safe.
#{var js = "\"alert(1);";}
<script>var value = "#js"; alert(value);</script>
output:
"alert(1);
Notice that the quote that I put in the string gets escaped to ", making me unable to break out of the string, so I cannot inject js.
I'd be interested to see if someone has a way of sanitizing this without putting it in quotes, but I am skeptical.
update 2:
Dealing with CSS
The examples you give are not about escaping strings, it is more about inserting untrusted CSS into your page. To do that, you will need something that can parse CSS. For example, it is not that you want the value to be encoded, you just want it not to include the dangerous stuff like url(javascript:), behavior, binding, etc. You'll need a CSS filtering tool for that.
HTML attributes
you are safe if you do this:
<div data-color="#color"></div>
Since razor encodes quotes, you won't be able to terminate the string early. That's as simple as it is to prevent XSS (barring some unknown vulnerability in razor). Your Json.Encode() uses the same idea.
BUT, you are doing somehting risky if you do this:
<div #attribute></div>
Again, it's not that you need an escaped string here, you want something that filters your attributes on any dangerous content. The fact is, that doing things this way is really messy, and I would advise against it. It is bad design because it is screwing up your separation of concerns and making it hard to secure your app from XSS. What you should do instead is add CSS classes if you want to change the style. If you need to set an attribute based on a variable in razor, use something else rather than injecting it into your HTML and hoping to filter it.
ex:
#{
var disabled = isDivDisabled ? "disabled" : "";
}
<div #disabled><div>

Client validation broken due to NamingContainer ID using ASCX as MVC-View

The situation
I'm currently migrating a WebForms application to MVC. Some old controls make heavy use of the WebForms form validation framework (the old validators, such as RequiredFieldValidator) and for the moment I am dependent on that specific behaviour.
It is far too costly to rewrite those controls entirely. But what I can do, is migrate them into ASCX-MVC-Views. That allows me to use the old validators and controls while using them via Html.Partial etc. in cshtml-files.
The problem
When I do that, I get various JS syntax errors in the generated validation code resulting from bad client IDs of the form controls:
<script type="text/javascript">
//<![CDATA[
var 1_ctl05 = document.all ? document.all["1_ctl05"] : document.getElementById("1_ctl05");
...
The problem here is, that variables may not start with a number (1). That number 1 is where the naming container will usually generate some prefix.
Upon inspection, I noticed that the ID of the ASCX-control is indeed "1", as is the NamingContainer.ID property of the validator and its parents.
Now, I can 'fix' this problem by implementing the PageLoad-Event, and setting this.ID to something starting with a character. But I get the feeling I'm either doing something wrong here (can I set the ID somewhere more properly?) or this is a bug.
Any suggestions?
Though still not entirely sure why the naming container is empty, I noticed that the faulty (and nasty) global JavaScript code can be avoided entirely by using the jQuery unobtrusive validation.
So the "fix" would be using unobtrusive validation whenever working with MVC and ASCX/ASPX forms.

What is the best way to call JS functions from Dust.js templates?

Let's say I have a partial template 'render_box' which is being called dynamically based on key {widget} in multiple places -
e.g
{"widget":"box"}
{>"render_{widget}":. /}
and I want to trigger jQuery event each time this 'render_box' finishes.
can I just include SCRIPT tag in the partial? I have read that this is not good practice due to performance. any ideas?

MVC HTML helper wrapper for jqPlot

I wish to create an MVC wrapper around jqPlot.
I want to have a helper object to render the required html container element and the required java scripts to draw the chart.
Something that will look like this:
#Html.jqPlot()
.ChartType(eChartTypes.PieChart)
.ChartData(someData)
.RenderChart();
Now I'm only at the initial design phase and I know what the jqPlot object should look like to achieve that, the problem I'm having is with the java script that suppose to be emitted to draw the actual chart using jqPlot.
Suppose I will render the following script in my .RenderChart() method
public string RenderChart()
{
string chartCode = string.format(#"
<script type="text/javascript" src="../src/plugins/jqplot.canvasTextRenderer.min.js"></script>
<script type="text/javascript" src="../src/plugins/jqplot.canvasAxisLabelRenderer.min.js"></script>
$(document).ready(function(){
var plot1 = $.jqplot ('{0}', [{1}]);
});
",this.ChartGuid, this.ChartData);
return chartCode;
}
The above is not actual code but just a general representation of the idea.
So the problem is that i don't want the Helper to emit the JS code into the body of the Html document, furthermore i cannot let it do that becuse some of the required scripts may be at the bottom of the html (as the best practice states).
Any suggestions ?
What would be the best way to emit JS code using an HTML helper if the situation requires it (like this one) ?
I think, listening to an even will be a possible solution, in this case the even of outputting or finishing the rendering of the footer. so maybe your code will give as an option to listen to an event and render at that moment, but this is of course platform dependent. I also worked on a php wrapper you can fork it here: https://github.com/oumsofiane1/jqplotPHPwrapper.git
and just implemented a helper, but of course you can extend that :-)
Hope this helps

multi line tag in grails or html

With a grails app and from a local database, I'm returning some text in a xml format.
I can return it well formed in a <textarea></textarea> tag with the correct indenting (tabulation, line return,...etc.)
I want to go a bit further. In the text I'm returning, there are some <img/> tags and I'd like to replace those tag by the real images themselves.
I searched around and found no solution as of now. I understood that you can't add an image to a textarea (other then in a background), and if I choose a div tag, I won't have the indenting anymore (and therefore, harder to read)
I was wondering if using a <g:textField/> or an other tag from the grails library will do the trick. And if so, How can I append them to a page using jquery.
For example, how to append a <g:textField/> in jquery. It doesn't interpret it and I get this error
SyntaxError: missing ) after argument list [Break On This Error]...+doc).append("<input type="text" id="FTMAP_"+nb_sec+"" ...
And in my javascript file, I have
$("#FTM_"+doc).append("<g:textField id='FTMAP_"+nb_sec+"' ... />
Any possible solutions ?
EDIT
I did forget to mention that my final intentions are to be able to modify the text (tags included) and to have a nice and neat indentation so that it is the easiest possible for the end user.
You are asking a few different questions:
1. Can I use a single HTML tag to include images inside pre-formatted text.
No. You will have to parse the text and translate it into styled text yourself.
2. Is there a tag in the grails standard tags to accomplish this for me?
No.
3. How can I add grails tags from my javascript code.
Grails tags are processed on the server-side, and javascript is processed on the client. This means you cannot directly add grails tags via javascript.
There are a couple methods that can accomplish the same result, however:
You can set a javascript variable to the rendered content of a grails tag. This solution is good for data that is known at the time of the initial request.
var tagOutput = "${g.textField(/* etc */)}";
You can make an ajax request for the content to be added. Then your server-side grails code can render the tags you need. This is better for realtime data, or data that will be updated more than once on a single rendered page.

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