1 package com.android.mail.utils;
2 
3 import android.test.AndroidTestCase;
4 import android.test.suitebuilder.annotation.SmallTest;
5 
6 /**
7  * These test cases verify the handling of more advanced cross-site scripting attacks.
8  */
9 @SmallTest
10 public class AdvancedHtmlSanitizerTest extends AndroidTestCase {
testSampleEmail()11     public void testSampleEmail() {
12         sanitize("<html>\n" +
13                         "<head>\n" +
14                         "<title>HTML E-mail</title>\n" +
15                         "<script>\n" +
16                         "alert(\"I am an alert box!\");\n" +
17                         "</script>\n" +
18                         "</head>\n" +
19                         "<body>\n" +
20                         "Body here\n" +
21                         "<br />\n" +
22                         "<a href=\"http://www.google.com\">Link to Google Search!</a>\n" +
23                         "<br />\n" +
24                         "<br />\n" +
25                         "<a onclick=\"alert('surprise!')\" href=\"#\">I am a link!</a>\n" +
26                         "<br />\n" +
27                         "Moar body here\n" +
28                         "</body>\n" +
29                         "</html>"
30                 ,
31                 "\n" +
32                         "\n" +
33                         "\n" +
34                         "\n" +
35                         "\n" +
36                         "<div>\n" +
37                         "Body here\n" +
38                         "<br />\n" +
39                         "<a href=\"http://www.google.com\">Link to Google Search!</a>\n" +
40                         "<br />\n" +
41                         "<br />\n" +
42                         "<a href=\"#\">I am a link!</a>\n" +
43                         "<br />\n" +
44                         "Moar body here\n" +
45                         "</div>\n");
46     }
47 
testXSS()48     public void testXSS() {
49         sanitize("'';!--\"<XSS>=&{()}", "&#39;&#39;;!--&#34;&#61;&amp;{()}");
50         sanitize("<img src=javascript:alert(String.fromCharCode(88,83,83))>", "");
51         sanitize("\\\";alert('XSS');//", "\\&#34;;alert(&#39;XSS&#39;);//");
52         sanitize("<br size=\"&{alert('XSS')}\">", "<br />");
53         sanitize("<xss style=\"xss:expression(alert('XSS'))\">", "");
54         sanitize("<xss style=\"behavior: url(xss.htc);\">", "");
55         sanitize("¼script¾alert(¢XSS¢)¼/script¾", "¼script¾alert(¢XSS¢)¼/script¾");
56         sanitize("<xml><i><b><img src=\"javas<!-- -->cript:alert('XSS')\"></b></i></xml>",
57                 "<i><b></b></i>");
58         sanitize("<xml src=\"xsstest.xml\" id=I></xml>", "");
59         sanitize("<!--[if gte IE 4]>\n" +
60                 " <SCRIPT>alert('XSS');</SCRIPT>\n" +
61                 " <![endif]-->", "");
62         sanitize("<body>\n" +
63                         "<?xml:namespace prefix=\"t\" ns=\"urn:schemas-microsoft-com:time\">\n" +
64                         "<?import namespace=\"t\" implementation=\"#default#time2\">\n" +
65                         "<t:set attributeName=\"innerHTML\" to=\"XSS<script defer>alert(\"XSS\")" +
66                         "</script>\">\n" +
67                         "</body></html>",
68                 "<div>\n" +
69                         "\n" +
70                         "\n" +
71                         "&#34;&gt;\n" +
72                         "</div>");
73     }
74 
75     /**
76      * Technically, RFC 2392 doesn't limit where CID urls may appear. But, Webview is unhappy
77      * handling them within link tags, so we only allow them in img src attributes until we see a
78      * reason to expand their acceptance.
79      */
testCIDurls()80     public void testCIDurls() {
81         sanitize("<img src=\"http://www.here.com/awesome.png\"/>",
82                 "<img src=\"http://www.here.com/awesome.png\" />");
83         sanitize("<img src=\"https://www.here.com/awesome.png\"/>",
84                 "<img src=\"https://www.here.com/awesome.png\" />");
85         sanitize("<img src=\"cid:ii_145bda161daf6f9c\"/>",
86                 "<img src=\"cid:ii_145bda161daf6f9c\" />");
87 
88         sanitize("<a href=\"http://www.here.com/awesome.png\"/>",
89                 "<a href=\"http://www.here.com/awesome.png\"></a>");
90         sanitize("<a href=\"https://www.here.com/awesome.png\"/>",
91                 "<a href=\"https://www.here.com/awesome.png\"></a>");
92         sanitize("<a href=\"cid:ii_145bda161daf6f9c\"/>", "");
93     }
94 
95     // todo the stock CssSchema in OWASP does NOT allow the float property; I experiment with adding
96     // todo it to see how much it beautifies HTML display (the risk seems to be that you can display
97     // todo content outside the bounds of your div and mislead the user with this technique)
testCSS_float()98     public void testCSS_float() {
99         sanitize("<div style=\"float:none\"></div>", "<div style=\"float:none\"></div>");
100         sanitize("<div style=\"float:left\"></div>", "<div style=\"float:left\"></div>");
101         sanitize("<div style=\"float:right\"></div>", "<div style=\"float:right\"></div>");
102         sanitize("<div style=\"float:inherit\"></div>", "<div style=\"float:inherit\"></div>");
103         sanitize("<div style=\"float:initial\"></div>", "<div></div>");
104         sanitize("<div style=\"float:garbage\"></div>", "<div></div>");
105     }
106 
107     // todo the stock CssSchema in OWASP does NOT allow the display property; I experiment with
108     // todo adding it to see how much it beautifies HTML display (the risk seems to be that you can
109     // todo display content outside the bounds of your div and mislead the user with this technique)
testCSS_display()110     public void testCSS_display() {
111         sanitize("<div style=\"display:inline\"></div>", "<div style=\"display:inline\"></div>");
112         sanitize("<div style=\"display:block\"></div>", "<div style=\"display:block\"></div>");
113         sanitize("<div style=\"display:flex\"></div>", "<div></div>");
114         sanitize("<div style=\"display:inline-block\"></div>",
115                 "<div style=\"display:inline-block\"></div>");
116         sanitize("<div style=\"display:inline-flex\"></div>", "<div></div>");
117         sanitize("<div style=\"display:inline-table\"></div>",
118                 "<div style=\"display:inline-table\"></div>");
119         sanitize("<div style=\"display:list-item\"></div>",
120                 "<div style=\"display:list-item\"></div>");
121         sanitize("<div style=\"display:run-in\"></div>", "<div style=\"display:run-in\"></div>");
122         sanitize("<div style=\"display:table\"></div>", "<div style=\"display:table\"></div>");
123         sanitize("<div style=\"display:table-caption\"></div>",
124                 "<div style=\"display:table-caption\"></div>");
125         sanitize("<div style=\"display:table-column-group\"></div>",
126                 "<div style=\"display:table-column-group\"></div>");
127         sanitize("<div style=\"display:table-header-group\"></div>",
128                 "<div style=\"display:table-header-group\"></div>");
129         sanitize("<div style=\"display:table-footer-group\"></div>",
130                 "<div style=\"display:table-footer-group\"></div>");
131         sanitize("<div style=\"display:table-row-group\"></div>",
132                 "<div style=\"display:table-row-group\"></div>");
133         sanitize("<div style=\"display:table-cell\"></div>",
134                 "<div style=\"display:table-cell\"></div>");
135         sanitize("<div style=\"display:table-column\"></div>",
136                 "<div style=\"display:table-column\"></div>");
137         sanitize("<div style=\"display:table-row\"></div>",
138                 "<div style=\"display:table-row\"></div>");
139         sanitize("<div style=\"display:none\"></div>", "<div style=\"display:none\"></div>");
140         sanitize("<div style=\"display:initial\"></div>", "<div></div>");
141         sanitize("<div style=\"display:inherit\"></div>", "<div style=\"display:inherit\"></div>");
142     }
143 
testTrimmingUrls()144     public void testTrimmingUrls() {
145         // todo Gmail strips the leading space on this href
146 //        sanitize("<a href=\"http://www.google.com \">Send mail</a>",
147 //                "<a href=\"http://www.google.com\">Send mail</a>");
148         sanitize("<a href=\" http://www.google.com\">Send mail</a>", "Send mail");
149         // todo Gmail strips the trailing space on this href
150 //        sanitize("<a href=\"http://www.google.com \">Send mail</a> ",
151 //                "<a href=\"http://www.google.com\">Send mail</a>");
152         sanitize("<a href=\"http://www.google.com \">Send mail</a>",
153                 "<a href=\"http://www.google.com \">Send mail</a>");
154         // todo Gmail strips the leading and trailing spaces on this href
155 //        sanitize("<a href=\" http://www.google.com \">Send mail</a> ",
156 //                "<a href=\"http://www.google.com\">Send mail</a>");
157         sanitize("<a href=\" http://www.google.com \">Send mail</a>", "Send mail");
158     }
159 
testDangerousHtml()160     public void testDangerousHtml() {
161         // body tag is translated to div tag
162         sanitize("<body dir=\"rtl\" onMouseOVer=\"alert(document.cookie)\">arr</body>",
163                 "<div dir=\"rtl\">arr</div>");
164         sanitize("<DIV ONCLICK=alert(document.cookie) style=color:red>arr</DIV>",
165                 "<div style=\"color:red\">arr</div>");
166         sanitize("<b style=position:absolute;left:0;top:0>arr</b>", "<b>arr</b>");
167 
168         // mailto: URLs on images are too easy to turn into DOS attacks
169         sanitize("<img src=\"mailto:\">", "");
170         sanitize("<img src=\"mailto:hcnidumolu@google.com\">", "");
171         sanitize("<img src=\"mailto:hcnidumolu@google.com\">", "");
172         sanitize("<img src=\" mailto:hcnidumolu@google.com\">", "");
173         sanitize("<img src=\"m&#x61;ilto:hcnidumolu@google.com\">", "");
174         sanitize("<img src=\"m&#x0D;ailto:hcnidumolu@google.com\">", "");
175         // todo Gmail doesn't escape the @ sign; OWASP does by default
176 //        sanitize("<a href=\"mailto:hcnidumolu@google.com\">Send mail </a>",
177 //                "<a href=\"mailto:hcnidumolu@google.com\">Send mail </a>");
178         sanitize("<a href=\"mailto:hcnidumolu@google.com\">Send mail </a>",
179                 "<a href=\"mailto:hcnidumolu&#64;google.com\">Send mail </a>");
180     }
181 
testSanitizingImgsWithoutSchemes()182     public void testSanitizingImgsWithoutSchemes() {
183         sanitize("<img src=\"//images1-gm-opensocial.googleusercontent.com/gadgets/proxy?" +
184                         "url=http://foo.bar/baz.png&container=gm&gadget=a&rewriteMime=image/*\">",
185 //                "<img src=\"//images1-gm-opensocial.googleusercontent.com/gadgets/proxy?" +
186 //                        "url=http://foo.bar/baz.png&amp;container=gm&amp;gadget=" +
187 //                        "a&amp;rewriteMime=image/*\">"); // todo Gmail doesn't escape the = signs
188                 "<img src=\"//images1-gm-opensocial.googleusercontent.com/gadgets/proxy?" +
189                         "url&#61;http://foo.bar/baz.png&amp;container&#61;gm&amp;gadget&#61;" +
190                         "a&amp;rewriteMime&#61;image/*\" />");
191     }
192 
testAdditionalURISchemes()193     public void testAdditionalURISchemes() {
194         // todo Gmail keeps a destinationless link; OWASP strips the a link completely
195 //        sanitize("<a href=\"foo:bar\" target=\"_blank\">link1</a>", "<a>link1</a>");
196         sanitize("<a href=\"foo:bar\" target=\"_blank\">link1</a>", "link1");
197         // todo Gmail keeps a destinationless a link; OWASP strips the a link completely
198 //        sanitize("<a href=\"baz:alanbs@google.com\">link2</a>", "<a>link2</a>");
199         sanitize("<a href=\"baz:alanbs@google.com\">link2</a>", "link2");
200     }
201 
testBackgroundAttribute()202     public void testBackgroundAttribute() {
203         sanitize("<div background=\"http://www.random.org/png\">stuff</div><div>more stuff</div>",
204                 "<div background=\"http://www.random.org/png\">stuff</div><div>more stuff</div>");
205     }
206 
testInputImage()207     public void testInputImage() {
208         sanitize("<input type=\"image\" src=\"http://random.org/png\">",
209                 "<input type=\"image\" src=\"http://random.org/png\" />");
210     }
211 
testImplicitInputImage()212     public void testImplicitInputImage() {
213         // In HTML 4.01, src attribute has meaning only when type="image" (which
214         // is not the default), but this happens in real life.
215         sanitize("<input src=\"http://random.org/png\">",
216                 "<input src=\"http://random.org/png\" />");
217     }
218 
testSerialization()219     public void testSerialization() {
220         // N.B. (literal) newlines must not occur in CSS strings.
221         // todo Gmail leaves this CSS style in place and escapes it; OWASP removes it all
222 //        sanitize("<a href=\"http://www.google.com\" style=\"font-family: 'expression; " +
223 //                        "\\a color:red;\\a font-family: completely unsanitized =(;' ;\">asdf</a>",
224 //                "<a href=\"http://www.google.com\" style=\"font-family:&#39;expression; " +
225 //                        "\\00000acolor:red;\\00000afont-family: completely unsanitized " +
226 //                        "=(;&#39;\">asdf</a>");
227         sanitize("<a href=\"http://www.google.com\" style=\"font-family: 'expression; " +
228                         "\\a color:red;\\a font-family: completely unsanitized =(;' ;\">asdf</a>",
229                 "<a href=\"http://www.google.com\">asdf</a>");
230     }
231 
testNoJS()232     public void testNoJS() {
233         // todo Gmail leaves this CSS in place and escapes it; OWASP removes it all
234 //        sanitize("<a href=\"http://www.google.com\" style=\"background-image: " +
235 //                "url('javascript:alert(1)')\"></a>",
236 //                "<a href=\"http://www.google.com\" style=\"background-image:" +
237 //                        "url(&#39;&#39;)\"></a>");
238         sanitize("<a href=\"http://www.google.com\" style=\"background-image: " +
239                 "url('javascript:alert(1)')\"></a>",
240                 "<a href=\"http://www.google.com\"></a>");
241     }
242 
testNoStyleElementByDefault()243     public void testNoStyleElementByDefault() {
244         sanitize("<head><style type='text/css'>verboten { color: red; }</style></head>" +
245                         "<body><p>test</p>",
246                 "<div><p>test</p></div>");
247     }
248 
testMessageFormation()249     public void testMessageFormation() {
250         sanitize("<table><tr><td><b>This is a simple message</b></td></tr></table>",
251                 "<table><tr><td><b>This is a simple message</b></td></tr></table>");
252         sanitize("<table><tr><td><b>This is a simple message",
253                 "<table><tr><td><b>This is a simple message</b></td></tr></table>");
254         sanitize("<table><tr>This is a simple message</b></td></tr></table>",
255                 "<table><tr><td>This is a simple message</td></tr></table>");
256         sanitize("This is a simple message</b></td></tr></table>", "This is a simple message");
257     }
258 
testViolatingTags()259     public void testViolatingTags() {
260         sanitize("<html><head><title>html to ruin your site</title>"
261                         + "<meta http-equiv=\"refresh\" content=\"5\" />"
262                         + "<link rel=\"stylesheet\" type=\"text/css\"  href=\"some site\"/>"
263                         + "<style type=\"text/css\"> h1 {color: red}</style>"
264                         + "</head><body><script>some script to run</script>"
265                         + "<noscript>Please enable Javascript and reload this page."
266                         + "Good things abound!</noscript>"
267                         + "<noframes>This page requires frames!</noframes>"
268                         + "<frameset cols = \"25%, 25%,*\">"
269                         + "<frame src=\"site1.htm\" />"
270                         + "<frame src=\"site2.htm\" />"
271                         + "<frame src=\"site3.htm\" /> "
272                         + "</frameset>"
273                         + "<table><tr><td>"
274                         + "Execute this <applet code=\"some evil site\"></td>"
275                         + "</tr></table></body></html>"
276                 ,
277                 "<div>"
278                         + "<table><tr><td>"
279                         + "Execute this </td>"
280                         + "</tr></table></div>"
281         );
282 
283         sanitize("Include this:<br/>"
284                         + "<object classid=\"clsid:FOOBAR\" id=\"Slider1\""
285                         + "declare=\"declare\">"
286                         + "<param name=\"some param\" value=\"1\" />"
287                         + "</object><br/>"
288                         + "<form method=\"POST\" action=\"http://www.somesite.com\""
289                         + "onsubmit=\"run some script\">"
290                         + "<input type=\"text\" onclick=\"run some script\" id=\"input\"/>"
291                         + "<input type=\"submit\" onfocus=\"run some script\" value=\"submit\"/>"
292                         + "</form>"
293                 ,
294                 "Include this:<br />"
295                         + "<br />"
296                         + "<form method=\"POST\" action=\"http://www.somesite.com\">"
297                         + "<input type=\"text\" />"
298                         + "<input type=\"submit\" value=\"submit\" />"
299                         + "</form>"
300         );
301     }
302 
testLinks()303     public void testLinks() {
304         sanitize("<a href=\"http://www.somesite.com\" target=\"_self\" "
305                         + "onclick=\"run some script\" onmouseover=\"run some script\">"
306                         + "click here</a>"
307                         + "<a href=\"javascript:run some script\">here</a>"
308                         + "<a href=\"someinternalpage.htm\">or here</a>"
309                 ,
310                 "<a href=\"http://www.somesite.com\">"
311                         + "click here</a>"
312                         + "here"
313                         + "<a href=\"someinternalpage.htm\">or here</a>"
314         );
315     }
316 
testExternalLinks()317     public void testExternalLinks() {
318         sanitize("This is a test <a href=http://google.com>here</a> "
319                         + "<img src=\"http://google.com/bogus.jpg\">"
320                         + "<img src=\"//google.com/bogus2.jpg\">"
321                         + "<img src=\"google.com/bogus3.jpg\">"
322                         + "<script>Hello</script> "
323                         + "<frameset><frame src=foo name=onlyFrame>hey</frame></frameset>"
324                 ,
325                 "This is a test <a href=\"http://google.com\">here</a> "
326                         + "<img src=\"http://google.com/bogus.jpg\" />"
327                         + "<img src=\"//google.com/bogus2.jpg\" />"
328                         + "<img src=\"google.com/bogus3.jpg\" /> "
329         );
330     }
331 
testNewHtmlWhitelist()332     public void testNewHtmlWhitelist() {
333         sanitize("<a href=http://google.com/boguslink>link</a>"
334                         + "<b>BOLD</b>"
335                         + "<i>italics</i>"
336                         + "<u>underlined</u>"
337                         + "<br/>break<br>break"
338                         + "<font size=+1>Big_font_gone</font>"
339                 ,
340                 "<a href=\"http://google.com/boguslink\">link</a>"
341                         + "<b>BOLD</b>"
342                         + "<i>italics</i>"
343                         + "<u>underlined</u>"
344                         + "<br />break<br />break"
345                         + "<font size=\"&#43;1\">Big_font_gone</font>"
346         );
347     }
348 
testRemoveBackticksInAttributes()349     public void testRemoveBackticksInAttributes() {
350         // IE treats backticks as quotes when re-serializing, but not when parsing
351         sanitize("<img alt=\"``onload=alert(1)\">",
352                 "<img alt=\"&#96;&#96;onload&#61;alert(1) \" />");
353         sanitize("<img alt=\"'``onload=alert(1)'\">",
354                 "<img alt=\"&#39;&#96;&#96;onload&#61;alert(1)&#39; \" />");
355         sanitize("<img alt=``onload=alert(1)\">", "<img alt=\"&#96;&#96;onload&#61;alert(1) \" />");
356 
357         // Make sure we're not fooled by escaped backticks
358         sanitize("<img alt=\"&#96;&#x0060;onload=alert(1)\">",
359                 "<img alt=\"&#96;&#96;onload&#61;alert(1) \" />");
360         sanitize("<img alt=\"&#x000060;&#x000060;onload=alert(1)\">",
361                 "<img alt=\"&#96;&#96;onload&#61;alert(1) \" />");
362 
363         // Misc. dangerous cases:
364         sanitize("<img alt=`x`onload=alert(1)>", "<img alt=\"&#96;x&#96;onload&#61;alert(1) \" />");
365         sanitize("<img alt=foo`x`onload=alert(1)>",
366                 "<img alt=\"foo&#96;x&#96;onload&#61;alert(1) \" />");
367         sanitize("<img alt=\"`whatever\">Hello world ` onload=alert(1) <br>",
368                 "<img alt=\"&#96;whatever \" />Hello world &#96; onload&#61;alert(1) <br />");
369 
370         // The tokenizer doesn't see these as entities because they lack a trailing semicolon, so it
371         // escapes the leading ampersands.
372         sanitize("<img alt=\"&#x000060&#x000060onload=alert(1)\">",
373                 "<img alt=\"&#96;&amp;#x000060onload&#61;alert(1) \" />");
374 
375         // Here there are no actual backticks, though there would be if we (or IE) did repeated
376         // unescaping.
377         sanitize("<img alt=\"&amp;#x000060&amp;#x000060onload=alert(2)\">",
378                 "<img alt=\"&amp;#x000060&amp;#x000060onload&#61;alert(2)\" />");
379         sanitize("<img alt=\"&amp;amp;#x000060&amp;amp;#x000060onload=alert(2)\">",
380                 "<img alt=\"&amp;amp;#x000060&amp;amp;#x000060onload&#61;alert(2)\" />");
381     }
382 
testMakeSafeStyle()383     public void testMakeSafeStyle() {
384         sanitize("<div style=\"color:red\"></div>", "<div style=\"color:red\"></div>");
385         sanitize("<div style=\"color:r\\ne\\t d  d\\r\\n\"></div>", "<div></div>");
386         sanitize("<div style=\"font-size:13.5pt; color:#804000 \"></div>",
387                 "<div style=\"font-size:13.5pt;color:#804000\"></div>");
388         sanitize("<div style=\"color:red;color\"></div>", "<div style=\"color:red\"></div>");
389         sanitize("<div style=\"color:red;color:a:b\"></div>", "<div style=\"color:red\"></div>");
390         sanitize("<div style=\"color:url(foo)\"></div>", "<div></div>");
391         sanitize("<div style=\"color:white; list-style:url(foo.gif);\"></div>",
392                 "<div style=\"color:white\"></div>");
393         sanitize("<div style=\"color:rgb(255, 0, 0)\"></div>",
394                 "<div style=\"color:rgb( 255 , 0 , 0 )\"></div>");
395         sanitize("<div style=\"background-color:rgb(80%,92%,18%)\"></div>",
396                 "<div style=\"background-color:rgb( 80% , 92% , 18% )\"></div>");
397         sanitize("<div style=\"border-left:1px rgb(0,255,0) solid\"></div>",
398                 "<div style=\"border-left:1px rgb( 0 , 255 , 0 ) solid\"></div>");
399         sanitize("<div style=\"background:rgb(0,255,0) url(foo) no-repeat top\"></div>",
400                 "<div style=\"background:rgb( 0 , 255 , 0 ) no-repeat top\"></div>");
401         sanitize("<div style=\"display:none; border-color: #ffeeff \"></div>",
402                 "<div style=\"display:none;border-color:#ffeeff\"></div>");
403 
404         // check for CSS3 border-radius
405         sanitize("<div style=\"border-radius:10px\"></div>",
406                 "<div style=\"border-radius:10px\"></div>");
407         sanitize("<div style=\"border-bottom-left-radius:10px\"></div>",
408                 "<div style=\"border-bottom-left-radius:10px\"></div>");
409         sanitize("<div style=\"border-bottom-right-radius:10px\"></div>",
410                 "<div style=\"border-bottom-right-radius:10px\"></div>");
411         sanitize("<div style=\"border-top-left-radius:10px\"></div>",
412                 "<div style=\"border-top-left-radius:10px\"></div>");
413         sanitize("<div style=\"border-top-right-radius:10px\"></div>",
414                 "<div style=\"border-top-right-radius:10px\"></div>");
415 
416         // allow positive margins
417         sanitize("<div style=\"margin:10 0 10 0\"></div>",
418                 "<div style=\"margin:10 0 10 0\"></div>");
419         sanitize("<div style=\"margin-left:40px\"></div>",
420                 "<div style=\"margin-left:40px\"></div>");
421 
422         // negative margin would allow it to slip out of the box
423         sanitize("<div style=\"margin-left:-10\"></div>", "<div></div>");
424 
425         // allow positive text-ident
426         sanitize("<div style=\"text-indent:10\"></div>", "<div style=\"text-indent:10\"></div>");
427         sanitize("<div style=\"text-indent:0\"></div>", "<div style=\"text-indent:0\"></div>");
428 
429         // todo Gmail disallows negative text-indents; OWASP is fine with them
430         // negative text-indent would allow it to slip out of the box
431 //        sanitize("<div style=\"text-indent:-10\"></div>", "<div></div>");
432         sanitize("<div style=\"text-indent:-10\"></div>", "<div style=\"text-indent:-10\"></div>");
433     }
434 
testMakeSafeStyleWithQuotedStrings()435     public void testMakeSafeStyleWithQuotedStrings() {
436         sanitize("<div style=\"font-family:'courier new',monospace;font-size:x-small\"></div>",
437                 "<div style=\"font-family:&#39;courier new&#39; , monospace;font-size:x-small\">" +
438                         "</div>");
439         sanitize("<div style=\"font-family:\"courier new\",monospace\"></div>", "<div></div>");
440         sanitize("<div style=\"font-family:''\"></div>", "<div></div>");
441         sanitize("<div style=\"font-family:a,''\"></div>",
442                 "<div style=\"font-family:&#39;a&#39; ,\"></div>");
443         sanitize("<div style=\"font-family:'',a,\"\",b\"></div>",
444                 "<div style=\"font-family:, &#39;a&#39; ,\"></div>");
445 
446         sanitize("<div style=\"font-family:'\"></div>", "<div></div>");
447         sanitize("<div style=\"font-family: 'courier new\",monospace;'\"></div>", "<div></div>");
448         sanitize("<div style=\"font-family: \"courier new',monospace;\"></div>", "<div></div>");
449     }
450 
testSeriouslyNoBackgroundImages()451     public void testSeriouslyNoBackgroundImages() {
452         sanitize("<div style=\"background:url('http://www.here.com/awesome.png')\"></div>",
453                 "<div></div>");
454         sanitize("<div style=\"background-image:url('http://www.here.com/awesome.png')\"></div>",
455                 "<div></div>");
456 
457         sanitize("<div style=\"background:url('javascript:evil()')\"></div>", "<div></div>");
458         sanitize("<div style=\"background-image:url('javascript:evil()')\"></div>", "<div></div>");
459     }
460 
testExpression()461     public void testExpression() {
462         sanitize("<div style=\"width: expression(alert(1))\"></div>", "<div></div>");
463     }
464 
testStrayUrlConsideredHarmful()465     public void testStrayUrlConsideredHarmful() {
466         sanitize("<div style=\"float:url(\"></div>", "<div></div>");
467         sanitize("<div style=\"float:\\075\\0072\\006C\\0028\"></div>", "<div></div>");
468     }
469 
testObjectionableFunctions()470     public void testObjectionableFunctions() {
471         sanitize("<div style=\"ex\\pression(123)\"></div>", "<div></div>");
472         sanitize("<div style=\"_expression(123)\"></div>", "<div></div>");
473         sanitize("<div style=\"expression(123)\"></div>", "<div></div>");
474         sanitize("<div style=\"funkyFunction(123)\"></div>", "<div></div>");
475 
476         sanitize("<div style=\"color:expression(alert('xss'))\"></div>", "<div></div>");
477         sanitize("<div style=\"color:expression(alert\\000028\\000027xss\\000027\\000029)\"></div>",
478                 "<div></div>");
479         sanitize("<div style=\"color:expression\\000028alert\\000028\\000027xss\\000027" +
480                 "\\000029\\000029\"></div>", "<div></div>");
481         sanitize("<div style=\"color:expressio\\00006E\\000028alert\\000028\\000027xss\\000027" +
482                 "\\000029\\000029\"\"></div>", "<div></div>");
483         sanitize("<div style=\"color:expression\\(alert\\)\"></div>", "<div></div>");
484     }
485 
testAbsolutePositionBanned()486     public void testAbsolutePositionBanned() {
487         sanitize("<div style=\"position: absolute\"></div>", "<div></div>");
488     }
489 
testNoTextShadow()490     public void testNoTextShadow() {
491         // todo Gmail disallows this text-shadow; OWASP is fine with it
492 //        sanitize("<div style=\"text-shadow: red -50px -100px 0px\"></div>", "<div></div>");
493         sanitize("<div style=\"text-shadow: red -50px -100px 0px\"></div>",
494                 "<div style=\"text-shadow:red -50px -100px 0px\"></div>");
495     }
496 
testToStyle()497     public void testToStyle() {
498         sanitize("<div style=\"color:red\"></div>", "<div style=\"color:red\"></div>");
499         sanitize("<div style=\"color: red\"></div>", "<div style=\"color:red\"></div>");
500         sanitize("<div style=\"color :red\"></div>", "<div style=\"color:red\"></div>");
501         sanitize("<div style=\"color :red; font-size:13.5pt;\"></div>",
502                 "<div style=\"color:red;font-size:13.5pt\"></div>");
503         sanitize("<div style=\"content:'\"'\"></div>", "<div></div>");
504     }
505 
testNoColorStrings()506     public void testNoColorStrings() {
507         sanitize("<div style=\"color: 'red';\"></div>", "<div></div>");
508     }
509 
testTolerateMalformedBorder()510     public void testTolerateMalformedBorder() {
511         sanitize("<div style=\"border-left-: solid thin red\"></div>", "<div></div>");
512     }
513 
testRgba()514     public void testRgba() {
515         sanitize("<div style=\"color:rgba(255, 0, 0, 0.5)\"></div>",
516                 "<div style=\"color:rgba( 255 , 0 , 0 , 0.5 )\"></div>");
517     }
518 
testFontStyle()519     public void testFontStyle() {
520         // todo Gmail accepts !important while OWASP discards it; this is only beauty, not security
521 //        sanitize("<div style=\"font-style:normal!important\"></div>",
522 //                "<div style=\"font-style:normal!important\"></div>");
523         sanitize("<div style=\"font-style:normal!important\"></div>",
524                 "<div style=\"font-style:normal\"></div>");
525         // todo Gmail accepts !important while OWASP discards it; this is only beauty, not security
526 //        sanitize("<div style=\"font-style:oblique !important\"></div>",
527 //                "<div style=\"font-style:oblique!important\"></div>");
528         sanitize("<div style=\"font-style:oblique !important\"></div>",
529                 "<div style=\"font-style:oblique\"></div>");
530         sanitize("<div style=\"font-style:italic\"></div>",
531                 "<div style=\"font-style:italic\"></div>");
532     }
533 
sanitize(String dirtyHTML, String expectedHTML)534     private void sanitize(String dirtyHTML, String expectedHTML) {
535         final String cleansedHTML = HtmlSanitizer.sanitizeHtml(dirtyHTML);
536         assertEquals(expectedHTML, cleansedHTML);
537     }
538 }
539