Merge branch 'master' of ssh://git.kitenet.net/srv/git/ikiwiki.info

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

diff --git a/doc/plugins/htmlscrubber.mdwn b/doc/plugins/htmlscrubber.mdwn
index 252fcd5d24d74ff2c4ed6fc1fa2f018a5f906082..b32c264df3f245688375093b88142ba2318683a7 100644 (file)
--- a/doc/plugins/htmlscrubber.mdwn
+++ b/doc/plugins/htmlscrubber.mdwn
@@ -1,6 +1,5 @@
-[[template id=plugin name=htmlscrubber core=1 included=1
-author="""[[Joey]]"""]]
-[[tag type/html type/core]]
+[[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.
@@ -8,9 +7,13 @@ 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` tags, and the `style` attribute.
 
-It uses the HTML::Scrubber perl module to perform its html
+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
 sanitisation, and this perl module also deals with various entity encoding
 tricks.
 
@@ -18,17 +21,23 @@ 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>
+* 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>
+* <a href="javascript&#x3A;alert('foo')">click me</a>