-[[template id=plugin name=htmlscrubber core=1 author="[[Joey]]"]]
-[[tag type/html]]
+[[!template id=plugin name=htmlscrubber core=1 author="[[Joey]]"]]
+[[!tag type/html]]
This plugin is enabled by default. It sanitizes the html on pages it renders
to avoid XSS attacks and the like.
It excludes all html tags and attributes except for those that are
whitelisted using the same lists as used by Mark Pilgrim's Universal Feed
Parser, documented at <http://feedparser.org/docs/html-sanitization.html>.
-Notably it strips `style` and `link`.
+Notably it strips `style` and `link` tags, and the `style` attribute.
-For the `style` attribute, it varys slightly from the Universal Feed
-Parser, accepting simple alphanumeric style attributes (style="foo"), but
-stripping anything more complex to avoid any of the ways to insert
-JavaScript via style attributes.
+All attributes that can be used to specify an url are checked to make sure
+that the url is in a known, safe scheme, and to block embedded javascript
+in such urls.
-It uses the [[cpan HTML::Scrubber]] perl module to perform its html
+It uses the [[!cpan HTML::Scrubber]] perl module to perform its html
sanitisation, and this perl module also deals with various entity encoding
tricks.
sanitisation is only a patch on the underlying gaping hole that is your web
browser.
-Note that enabling or disabling the htmlscrubber plugin also affects some other
-HTML-related functionality, such as whether [[meta]] allows potentially unsafe
-HTML tags.
+Note that enabling or disabling the htmlscrubber plugin also affects some
+other HTML-related functionality, such as whether [[meta]] allows
+potentially unsafe HTML tags.
+
+The `htmlscrubber_skip` configuration setting can be used to skip scrubbing
+of some pages. Set it to a [[ikiwiki/PageSpec]], such as
+`posts/* and !comment(*) and !*/Discussion`, and pages matching that can have
+all the evil CSS, JavsScript, and unsafe html elements you like. One safe
+way to use this is to use [[lockedit]] to lock those pages, so only admins
+can edit them.
----
* <span style="background: url(javascript:window.location='http://example.org/')">CSS script test</span>
* <span style="any: expression(window.location='http://example.org/')">entity-encoded CSS script test</span>
* <span style="any: expression(window.location='http://example.org/')">entity-encoded CSS script test</span>
-* <span style="pretty">OTOH, this is ok, and will be accepted</a>
+* <a href="javascript:alert('foo')">click me</a>