content/base/public/nsTreeSanitizer.h@a63d609f5ebe
content/base/public/nsTreeSanitizer.h
Thu, 15 Jan 2015 15:55:04 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 15 Jan 2015 15:55:04 +0100
- branch
- TOR_BUG_9701
- changeset 9
- a63d609f5ebe
- permissions
- -rw-r--r--
Back out 97036ab72558 which inappropriately compared turds to third parties.
1 /* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
5 #ifndef nsTreeSanitizer_h_
6 #define nsTreeSanitizer_h_
8 #include "mozilla/css/StyleRule.h"
9 #include "nsIPrincipal.h"
10 #include "mozilla/dom/Element.h"
12 class nsIContent;
14 /**
15 * See the documentation of nsIParserUtils::sanitize for documentation
16 * about the default behavior and the configuration options of this sanitizer.
17 */
18 class MOZ_STACK_CLASS nsTreeSanitizer {
20 public:
22 /**
23 * The constructor.
24 *
25 * @param aFlags Flags from nsIParserUtils
26 */
27 nsTreeSanitizer(uint32_t aFlags = 0);
29 static void InitializeStatics();
30 static void ReleaseStatics();
32 /**
33 * Sanitizes a disconnected DOM fragment freshly obtained from a parser.
34 * The argument must be of type nsINode::eDOCUMENT_FRAGMENT and,
35 * consequently, must not be in the document. Furthermore, the fragment
36 * must have just come from a parser so that it can't have mutation
37 * event listeners set on it.
38 */
39 void Sanitize(nsIContent* aFragment);
41 /**
42 * Sanitizes a disconnected (not in a docshell) document freshly obtained
43 * from a parser. The document must not be embedded in a docshell and must
44 * not have had a chance to get mutation event listeners attached to it.
45 * The root element must be <html>.
46 */
47 void Sanitize(nsIDocument* aDocument);
49 private:
51 /**
52 * Whether <style> and style="" are allowed.
53 */
54 bool mAllowStyles;
56 /**
57 * Whether comment nodes are allowed.
58 */
59 bool mAllowComments;
61 /**
62 * Whether HTML <font>, <center>, bgcolor="", etc., are dropped.
63 */
64 bool mDropNonCSSPresentation;
66 /**
67 * Whether to remove forms and form controls (excluding fieldset/legend).
68 */
69 bool mDropForms;
71 /**
72 * Whether only cid: embeds are allowed.
73 */
74 bool mCidEmbedsOnly;
76 /**
77 * Whether to drop <img>, <video>, <audio> and <svg>.
78 */
79 bool mDropMedia;
81 /**
82 * Whether we are sanitizing a full document (as opposed to a fragment).
83 */
84 bool mFullDocument;
86 void SanitizeChildren(nsINode* aRoot);
88 /**
89 * Queries if an element must be replaced with its children.
90 * @param aNamespace the namespace of the element the question is about
91 * @param aLocal the local name of the element the question is about
92 * @return true if the element must be replaced with its children and
93 * false if the element is to be kept
94 */
95 bool MustFlatten(int32_t aNamespace, nsIAtom* aLocal);
97 /**
98 * Queries if an element including its children must be removed.
99 * @param aNamespace the namespace of the element the question is about
100 * @param aLocal the local name of the element the question is about
101 * @param aElement the element node itself for inspecting attributes
102 * @return true if the element and its children must be removed and
103 * false if the element is to be kept
104 */
105 bool MustPrune(int32_t aNamespace,
106 nsIAtom* aLocal,
107 mozilla::dom::Element* aElement);
109 /**
110 * Checks if a given local name (for an attribute) is on the given list
111 * of URL attribute names.
112 * @param aURLs the list of URL attribute names
113 * @param aLocalName the name to search on the list
114 * @return true if aLocalName is on the aURLs list and false otherwise
115 */
116 bool IsURL(nsIAtom*** aURLs, nsIAtom* aLocalName);
118 /**
119 * Removes dangerous attributes from the element. If the style attribute
120 * is allowed, its value is sanitized. The values of URL attributes are
121 * sanitized, except src isn't sanitized when it is allowed to remain
122 * potentially dangerous.
123 *
124 * @param aElement the element whose attributes should be sanitized
125 * @param aAllowed the whitelist of permitted local names to use
126 * @param aURLs the local names of URL-valued attributes
127 * @param aAllowXLink whether XLink attributes are allowed
128 * @param aAllowStyle whether the style attribute is allowed
129 * @param aAllowDangerousSrc whether to leave the value of the src
130 * attribute unsanitized
131 */
132 void SanitizeAttributes(mozilla::dom::Element* aElement,
133 nsTHashtable<nsISupportsHashKey>* aAllowed,
134 nsIAtom*** aURLs,
135 bool aAllowXLink,
136 bool aAllowStyle,
137 bool aAllowDangerousSrc);
139 /**
140 * Remove the named URL attribute from the element if the URL fails a
141 * security check.
142 *
143 * @param aElement the element whose attribute to possibly modify
144 * @param aNamespace the namespace of the URL attribute
145 * @param aLocalName the local name of the URL attribute
146 * @return true if the attribute was removed and false otherwise
147 */
148 bool SanitizeURL(mozilla::dom::Element* aElement,
149 int32_t aNamespace,
150 nsIAtom* aLocalName);
152 /**
153 * Checks a style rule for the presence of the 'binding' CSS property and
154 * removes that property from the rule and reserializes in case the
155 * property was found.
156 *
157 * @param aRule The style rule to check
158 * @param aRuleText the serialized mutated rule if the method returns true
159 * @return true if the rule was modified and false otherwise
160 */
161 bool SanitizeStyleRule(mozilla::css::StyleRule* aRule,
162 nsAutoString &aRuleText);
164 /**
165 * Parses a style sheet and reserializes it with the 'binding' property
166 * removed if it was present.
167 *
168 * @param aOrigin the original style sheet source
169 * @param aSanitized the reserialization without 'binding'; only valid if
170 * this method return true
171 * @param aDocument the document the style sheet belongs to
172 * @param aBaseURI the base URI to use
173 * @return true if the 'binding' property was encountered and false
174 * otherwise
175 */
176 bool SanitizeStyleSheet(const nsAString& aOriginal,
177 nsAString& aSanitized,
178 nsIDocument* aDocument,
179 nsIURI* aBaseURI);
181 /**
182 * Removes all attributes from an element node.
183 */
184 void RemoveAllAttributes(nsIContent* aElement);
186 /**
187 * The whitelist of HTML elements.
188 */
189 static nsTHashtable<nsISupportsHashKey>* sElementsHTML;
191 /**
192 * The whitelist of non-presentational HTML attributes.
193 */
194 static nsTHashtable<nsISupportsHashKey>* sAttributesHTML;
196 /**
197 * The whitelist of presentational HTML attributes.
198 */
199 static nsTHashtable<nsISupportsHashKey>* sPresAttributesHTML;
201 /**
202 * The whitelist of SVG elements.
203 */
204 static nsTHashtable<nsISupportsHashKey>* sElementsSVG;
206 /**
207 * The whitelist of SVG attributes.
208 */
209 static nsTHashtable<nsISupportsHashKey>* sAttributesSVG;
211 /**
212 * The whitelist of SVG elements.
213 */
214 static nsTHashtable<nsISupportsHashKey>* sElementsMathML;
216 /**
217 * The whitelist of MathML attributes.
218 */
219 static nsTHashtable<nsISupportsHashKey>* sAttributesMathML;
221 /**
222 * Reusable null principal for URL checks.
223 */
224 static nsIPrincipal* sNullPrincipal;
225 };
227 #endif // nsTreeSanitizer_h_
