Content Security Policy "data" not working for base64 Images in Chrome 28
Content Security-PolicyContent Security-Policy Problem Overview
In this simple example, I'm trying to set a CSP header with the meta http-equiv header. I included a base64 image and I'm trying to make Chrome load the image.
I thought the data keyword should do that,
but somehow it's not working.
I just get the following error in Developer Tools:
> Refused to load the image 'data:image/png;base64,R0lGODlhDwAPAOZEAMkJCfAwMMYGBtZMTP75+euIiPFBP+hVVf3v7…nw7yk4Mjr6GLUY+joiBI2QAACABwJDCHgoKOHEoAYVBAgY8GGAxAoNGAmiwMHBCgccKDAKBAA7' because it violates the following Content Security Policy directive: "img-src 'self' data".
The example code (JSFiddle is not working for this example because I cannot set meta header there):
<html>
<head>
<meta http-equiv="Content-Security-Policy" content="
default-src 'none';
style-src 'self' 'unsafe-inline';
img-src 'self' data;
" />
<style>
#helloCSP {
width: 50px;
height: 50px;
background: url(data:image/png;base64,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) no-repeat;
border: 1px solid red;
}
</style>
</head>
<body>
<h1>CSP</h1>
<div id="helloCSP"></div>
</body>
</html>
You can also open this example here:
https://dl.dropboxusercontent.com/u/638360/ps/csp.html
Content Security-Policy Solutions
Solution 1 - Content Security-Policy
According to the grammar in the CSP spec, you need to specify schemes as scheme:, not just scheme. So, you need to change the image source directive to:
img-src 'self' data:;
Solution 2 - Content Security-Policy
Try this
data to load:
<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 4 5'><path fill='#343a40' d='M2 0L0 2h4zm0 5L0 3h4z'/></svg>
get a utf8 to base64 convertor and convert the "svg" string to:
PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHZpZXdCb3g9JzAgMCA0IDUn
PjxwYXRoIGZpbGw9JyMzNDNhNDAnIGQ9J00yIDBMMCAyaDR6bTAgNUwwIDNoNHonLz48L3N2Zz4=
and the CSP is
img-src data: image/svg+xml;base64,PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHZpZXdCb3g9JzAgMCA0IDUn
PjxwYXRoIGZpbGw9JyMzNDNhNDAnIGQ9J00yIDBMMCAyaDR6bTAgNUwwIDNoNHonLz48L3N2Zz4=