1/*
2 * Copyright (C) 2013 Google 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 GOOGLE, 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
27#include "config.h"
28#include "core/dom/SandboxFlags.h"
29
30#include "core/html/parser/HTMLParserIdioms.h"
31#include "wtf/text/StringBuilder.h"
32
33namespace blink {
34
35SandboxFlags parseSandboxPolicy(const String& policy, String& invalidTokensErrorMessage)
36{
37    // http://www.w3.org/TR/html5/the-iframe-element.html#attr-iframe-sandbox
38    // Parse the unordered set of unique space-separated tokens.
39    SandboxFlags flags = SandboxAll;
40    unsigned length = policy.length();
41    unsigned start = 0;
42    unsigned numberOfTokenErrors = 0;
43    StringBuilder tokenErrors;
44    while (true) {
45        while (start < length && isHTMLSpace<UChar>(policy[start]))
46            ++start;
47        if (start >= length)
48            break;
49        unsigned end = start + 1;
50        while (end < length && !isHTMLSpace<UChar>(policy[end]))
51            ++end;
52
53        // Turn off the corresponding sandbox flag if it's set as "allowed".
54        String sandboxToken = policy.substring(start, end - start);
55        if (equalIgnoringCase(sandboxToken, "allow-same-origin")) {
56            flags &= ~SandboxOrigin;
57        } else if (equalIgnoringCase(sandboxToken, "allow-forms")) {
58            flags &= ~SandboxForms;
59        } else if (equalIgnoringCase(sandboxToken, "allow-scripts")) {
60            flags &= ~SandboxScripts;
61            flags &= ~SandboxAutomaticFeatures;
62        } else if (equalIgnoringCase(sandboxToken, "allow-top-navigation")) {
63            flags &= ~SandboxTopNavigation;
64        } else if (equalIgnoringCase(sandboxToken, "allow-popups")) {
65            flags &= ~SandboxPopups;
66        } else if (equalIgnoringCase(sandboxToken, "allow-pointer-lock")) {
67            flags &= ~SandboxPointerLock;
68        } else if (equalIgnoringCase(sandboxToken, "allow-orientation-lock")) {
69            flags &= ~SandboxOrientationLock;
70        } else {
71            if (numberOfTokenErrors)
72                tokenErrors.appendLiteral(", '");
73            else
74                tokenErrors.append('\'');
75            tokenErrors.append(sandboxToken);
76            tokenErrors.append('\'');
77            numberOfTokenErrors++;
78        }
79
80        start = end + 1;
81    }
82
83    if (numberOfTokenErrors) {
84        if (numberOfTokenErrors > 1)
85            tokenErrors.appendLiteral(" are invalid sandbox flags.");
86        else
87            tokenErrors.appendLiteral(" is an invalid sandbox flag.");
88        invalidTokensErrorMessage = tokenErrors.toString();
89    }
90
91    return flags;
92}
93
94}
95