* htmlscrubber security fix: Block javascript in uris.

* Add htmlscrubber test suite.

diff --git a/IkiWiki/Plugin/htmlscrubber.pm b/IkiWiki/Plugin/htmlscrubber.pm
index bc613f92477ef55ef384f8a1bbf2887670c0e7a7..25caa8a506cdf5ab8ea0c9b0d3e9e935f62bd6f8 100644 (file)
--- a/IkiWiki/Plugin/htmlscrubber.pm
+++ b/IkiWiki/Plugin/htmlscrubber.pm
@@ -18,6 +18,28 @@ my $_scrubber;
 sub scrubber { #{{{
        return $_scrubber if defined $_scrubber;
        
 sub scrubber { #{{{
        return $_scrubber if defined $_scrubber;
        

+       # Only known uri schemes are allowed to avoid all the ways of
+       # embedding javascrpt.
+       # List at http://en.wikipedia.org/wiki/URI_scheme
+       my $uri_schemes=join("|",
+               # IANA registered schemes
+               "http", "https", "ftp", "mailto", "file", "telnet", "gopher",
+               "aaa", "aaas", "acap",  "cap", "cid", "crid", 
+               "dav", "dict", "dns", "fax", "go", "h323", "im", "imap",
+               "ldap", "mid", "news", "nfs", "nntp", "pop", "pres",
+               "sip", "sips", "snmp", "tel", "urn", "wais", "xmpp",
+               "z39.50r", "z39.50s",
+               # data is a special case. Allow data:text/<image>, but
+               # disallow data:text/javascript and everything else.
+               qr/data:text\/(?:png|gif|jpeg)/,
+               # Selected unofficial schemes
+               "about", "aim", "callto", "cvs", "ed2k", "feed", "fish", "gg",
+               "irc", "ircs", "lastfm", "ldaps", "magnet", "mms",
+               "msnim", "notes", "rsync", "secondlife", "skype", "ssh",
+               "sftp", "sms", "steam", "webcal", "ymsgr",
+       );
+       my $link=qr/^(?:$uri_schemes:|[^:]+$)/i;
+

        eval q{use HTML::Scrubber};
        error($@) if $@;
        # Lists based on http://feedparser.org/docs/html-sanitization.html
        eval q{use HTML::Scrubber};
        error($@) if $@;
        # Lists based on http://feedparser.org/docs/html-sanitization.html


@@ -35,23 +57,27 @@ sub scrubber { #{{{
                }],
                default => [undef, { (
                        map { $_ => 1 } qw{
                }],
                default => [undef, { (
                        map { $_ => 1 } qw{

-                               abbr accept accept-charset accesskey action
+                               abbr accept accept-charset accesskey

                                align alt axis border cellpadding cellspacing
                                char charoff charset checked cite class
                                clear cols colspan color compact coords
                                datetime dir disabled enctype for frame
                                align alt axis border cellpadding cellspacing
                                char charoff charset checked cite class
                                clear cols colspan color compact coords
                                datetime dir disabled enctype for frame

-                               headers height href hreflang hspace id ismap
+                               headers height hreflang hspace id ismap

                                label lang longdesc maxlength media method
                                multiple name nohref noshade nowrap prompt
                                readonly rel rev rows rowspan rules scope
                                label lang longdesc maxlength media method
                                multiple name nohref noshade nowrap prompt
                                readonly rel rev rows rowspan rules scope

-                               selected shape size span src start summary
+                               selected shape size span start summary

                                tabindex target title type usemap valign
                                value vspace width
                                tabindex target title type usemap valign
                                value vspace width

-                               poster autoplay loopstart loopend end
+                               autoplay loopstart loopend end

                                playcount controls 
                        } ),
                        "/" => 1, # emit proper <hr /> XHTML
                                playcount controls 
                        } ),
                        "/" => 1, # emit proper <hr /> XHTML

-                       }],
+                       href => $link,
+                       src => $link,
+                       action => $link,
+                       poster => $link,
+               }],

        );
        return $_scrubber;
 } # }}}
        );
        return $_scrubber;
 } # }}}

diff --git a/debian/changelog b/debian/changelog
index 420cef5ad9e0e3a440936f756b4b78c9fc693fdd..fb8d6bc5b01d2c5429c10c7213d7b375546c5770 100644 (file)
--- a/debian/changelog
+++ b/debian/changelog
@@ -8,6 +8,10 @@ ikiwiki (2.40) UNRELEASED; urgency=low
     the underlay to support either setting of prefix_directives.  Add NEWS
     entry with migration information.
 
     the underlay to support either setting of prefix_directives.  Add NEWS
     entry with migration information.
 

+  [ Joey Hess ]
+  * htmlscrubber security fix: Block javascript in uris.
+  * Add htmlscrubber test suite.
+

  -- Josh Triplett <josh@freedesktop.org>  Sat, 09 Feb 2008 23:01:19 -0800
 
 ikiwiki (2.31) unstable; urgency=low
  -- Josh Triplett <josh@freedesktop.org>  Sat, 09 Feb 2008 23:01:19 -0800
 
 ikiwiki (2.31) unstable; urgency=low

diff --git a/doc/plugins/htmlscrubber.mdwn b/doc/plugins/htmlscrubber.mdwn
index 6ce297a86bbc48ddda36dc6b51eb8ada39566312..d7bcf8099e00e3dd116bddd60ab67c8082639f1f 100644 (file)
--- a/doc/plugins/htmlscrubber.mdwn
+++ b/doc/plugins/htmlscrubber.mdwn
@@ -36,3 +36,4 @@ plugin is active:
 * <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="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>

diff --git a/t/htmlize.t b/t/htmlize.t
index 9e2e3ec594eded64c1b9388c705db515583b89e1..edf357010a0b551b58f895908cfd1858bc9e5f95 100755 (executable)
--- a/t/htmlize.t
+++ b/t/htmlize.t
@@ -1,7 +1,7 @@
 #!/usr/bin/perl
 use warnings;
 use strict;
 #!/usr/bin/perl
 use warnings;
 use strict;

-use Test::More tests => 16;
+use Test::More tests => 26;

 use Encode;
 
 BEGIN { use_ok("IkiWiki"); }
 use Encode;
 
 BEGIN { use_ok("IkiWiki"); }


@@ -20,7 +20,6 @@ is(IkiWiki::htmlize("foo", "mdwn", readfile("t/test1.mdwn")),
 ok(IkiWiki::htmlize("foo", "mdwn", readfile("t/test2.mdwn")),
        "this file crashes markdown if it's fed in as decoded utf-8");
 
 ok(IkiWiki::htmlize("foo", "mdwn", readfile("t/test2.mdwn")),
        "this file crashes markdown if it's fed in as decoded utf-8");
 

-# embedded javascript sanitisation tests

 sub gotcha {
        my $html=IkiWiki::htmlize("foo", "mdwn", shift);
        return $html =~ /GOTCHA/;
 sub gotcha {
        my $html=IkiWiki::htmlize("foo", "mdwn", shift);
        return $html =~ /GOTCHA/;


@@ -41,10 +40,31 @@ ok(!gotcha(q{<span style="&#97;&#110;&#121;&#58;&#32;&#101;&#120;&#112;&#114;&#1
        "another entity-encoded CSS script test");
 ok(!gotcha(q{<script>GOTCHA</script>}),
        "script tag");
        "another entity-encoded CSS script test");
 ok(!gotcha(q{<script>GOTCHA</script>}),
        "script tag");

+ok(!gotcha(q{<form action="javascript:alert('GOTCHA')">foo</form>}),
+       "form action with javascript");
+ok(!gotcha(q{<video poster="javascript:alert('GOTCHA')" href="foo.avi">foo</video>}),
+       "video poster with javascript");

 ok(!gotcha(q{<span style="background: url(javascript:window.location=GOTCHA)">a</span>}),
        "CSS script test");
 ok(!gotcha(q{<span style="background: url(javascript:window.location=GOTCHA)">a</span>}),
        "CSS script test");

+ok(! gotcha(q{<img src="data:text/javascript:GOTCHA">}),
+       "data:text/javascript (jeez!)");
+ok(gotcha(q{<img src="data:text/png:GOTCHA">}), "data:text/png");
+ok(gotcha(q{<img src="data:text/gif:GOTCHA">}), "data:text/gif");
+ok(gotcha(q{<img src="data:text/jpeg:GOTCHA">}), "data:text/jpeg");

 ok(gotcha(q{<p>javascript:alert('GOTCHA')</p>}),
        "not javascript AFAIK (but perhaps some web browser would like to
        be perverse and assume it is?)");
 ok(gotcha(q{<img src="javascript.png?GOTCHA">}), "not javascript");
 ok(gotcha(q{<a href="javascript.png?GOTCHA">foo</a>}), "not javascript");
 ok(gotcha(q{<p>javascript:alert('GOTCHA')</p>}),
        "not javascript AFAIK (but perhaps some web browser would like to
        be perverse and assume it is?)");
 ok(gotcha(q{<img src="javascript.png?GOTCHA">}), "not javascript");
 ok(gotcha(q{<a href="javascript.png?GOTCHA">foo</a>}), "not javascript");

+is(IkiWiki::htmlize("foo", "mdwn",
+       q{<img alt="foo" src="foo.gif">}),
+       q{<img alt="foo" src="foo.gif">}, "img with alt tag allowed");
+is(IkiWiki::htmlize("foo", "mdwn",
+       q{<a href="http://google.com/">}),
+       q{<a href="http://google.com/">}, "absolute url allowed");
+is(IkiWiki::htmlize("foo", "mdwn",
+       q{<a href="foo.html">}),
+       q{<a href="foo.html">}, "relative url allowed");
+is(IkiWiki::htmlize("foo", "mdwn",
+       q{<span class="foo">bar</span>}),
+       q{<span class="foo">bar</span>}, "class attribute allowed");