1/*
2 * Copyright (C) 2009 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "core/html/canvas/CanvasRenderingContext.h"
28
29#include "core/html/canvas/CanvasImageSource.h"
30#include "platform/weborigin/SecurityOrigin.h"
31
32namespace blink {
33
34CanvasRenderingContext::CanvasRenderingContext(HTMLCanvasElement* canvas)
35    : m_canvas(canvas)
36{
37
38}
39
40bool CanvasRenderingContext::wouldTaintOrigin(CanvasImageSource* imageSource)
41{
42    const KURL& sourceURL = imageSource->sourceURL();
43    bool hasURL = (sourceURL.isValid() && !sourceURL.isAboutBlankURL());
44
45    if (hasURL) {
46        if (sourceURL.protocolIsData() || m_cleanURLs.contains(sourceURL.string()))
47            return false;
48        if (m_dirtyURLs.contains(sourceURL.string()))
49            return true;
50    }
51
52    bool taintOrigin = imageSource->wouldTaintOrigin(canvas()->securityOrigin());
53
54    if (hasURL) {
55        if (taintOrigin)
56            m_dirtyURLs.add(sourceURL.string());
57        else
58            m_cleanURLs.add(sourceURL.string());
59    }
60    return taintOrigin;
61}
62
63} // namespace blink
64