* Allow simple alphanumeric style attribute values in the htmlscrubber. This

[git.ikiwiki.info.git] / doc / plugins / htmlscrubber.mdwn

diff --git a/doc/plugins/htmlscrubber.mdwn b/doc/plugins/htmlscrubber.mdwn
index bc2173890b2c106fdfa6cba2392f66146260e710..cc749e2dc8b3619e9f7739c1613624f356282c52 100644 (file)
--- a/doc/plugins/htmlscrubber.mdwn
+++ b/doc/plugins/htmlscrubber.mdwn
@@ -1,12 +1,20 @@
+[[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`, `link`, and the `style` attribute.
+Notably it strips `style` and `link`.
+
+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.
 
-It uses the 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.
 
@@ -14,19 +22,23 @@ While I believe that this makes ikiwiki as resistant to malicious html
 content as anything else on the web, I cannot guarantee that it will
 actually protect every user of every browser from every browser security
 hole, badly designed feature, etc. I can provide NO WARRANTY, like it says
-in ikiwiki's [GPL](GPL) license. 
+in ikiwiki's [[GPL]] license. 
 
 The web's security model is *fundamentally broken*; ikiwiki's html
 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.
+
 ----
 
 Some examples of embedded javascript that won't be let through when this
 plugin is active:
 
-* <span style="background: url(javascript:window.location='http://example.org/')">test</span>
-* <span style="&#x61;&#x6e;&#x79;&#x3a;&#x20;&#x65;&#x78;&#x70;&#x72;&#x65;&#x73;&#x73;&#x69;&#x6f;&#x6e;&#x28;&#x77;&#x69;&#x6e;&#x64;&#x6f;&#x77;&#x2e;&#x6c;&#x6f;&#x63;&#x61;&#x74;&#x69;&#x6f;&#x6e;&#x3d;&#x27;&#x68;&#x74;&#x74;&#x70;&#x3a;&#x2f;&#x2f;&#x65;&#x78;&#x61;&#x6d;&#x70;&#x6c;&#x65;&#x2e;&#x6f;&#x72;&#x67;&#x2f;&#x27;&#x29;">test</span>
-* <span style="&#97;&#110;&#121;&#58;&#32;&#101;&#120;&#112;&#114;&#101;&#115;&#115;&#105;&#111;&#110;&#40;&#119;&#105;&#110;&#100;&#111;&#119;&#46;&#108;&#111;&#99;&#97;&#116;&#105;&#111;&#110;&#61;&#39;&#104;&#116;&#116;&#112;&#58;&#47;&#47;&#101;&#120;&#97;&#109;&#112;&#108;&#101;&#46;&#111;&#114;&#103;&#47;&#39;&#41;">test</span>
-
-[[tag plugins/type/html plugins/type/core]]
+* script tag test <script>window.location='http://example.org';</script>
+* <span style="background: url(javascript:window.location='http://example.org/')">CSS script test</span>
+* <span style="&#x61;&#x6e;&#x79;&#x3a;&#x20;&#x65;&#x78;&#x70;&#x72;&#x65;&#x73;&#x73;&#x69;&#x6f;&#x6e;&#x28;&#x77;&#x69;&#x6e;&#x64;&#x6f;&#x77;&#x2e;&#x6c;&#x6f;&#x63;&#x61;&#x74;&#x69;&#x6f;&#x6e;&#x3d;&#x27;&#x68;&#x74;&#x74;&#x70;&#x3a;&#x2f;&#x2f;&#x65;&#x78;&#x61;&#x6d;&#x70;&#x6c;&#x65;&#x2e;&#x6f;&#x72;&#x67;&#x2f;&#x27;&#x29;">entity-encoded CSS script test</span>
+* <span style="&#97;&#110;&#121;&#58;&#32;&#101;&#120;&#112;&#114;&#101;&#115;&#115;&#105;&#111;&#110;&#40;&#119;&#105;&#110;&#100;&#111;&#119;&#46;&#108;&#111;&#99;&#97;&#116;&#105;&#111;&#110;&#61;&#39;&#104;&#116;&#116;&#112;&#58;&#47;&#47;&#101;&#120;&#97;&#109;&#112;&#108;&#101;&#46;&#111;&#114;&#103;&#47;&#39;&#41;">entity-encoded CSS script test</span>
+* <span style="pretty">OTOH, this is ok, and will be accepted</a>