NAME
HTML::Scrubber::StripScripts - strip scripting from HTML
SYNOPSIS
use HTML::Scrubber::StripScripts;
my $hss = HTML::Scrubber::StripScripts->new(
Allow_src => 1,
Allow_href => 1,
Allow_a_mailto => 1,
Whole_document => 1,
Block_tags => ['hr'],
);
my $clean_html = $hss->scrub($dirty_html);
DESCRIPTION
This module provides a preworked configuration for HTML::Scrubber,
configuring it to leave as much non-scripting markup in place as
possible while being certain to eliminate all scripting constructs. This
allows web applications to display HTML originating from an untrusted
source without introducing XSS (cross site scripting) vulnerabilities.
CONSTRUCTORS
new ( CONFIG )
Returns a new "HTML::Scrubber" object, configured with a filtering
policy based on a whitelist of XSS-free tags and attributes. If
present, the CONFIG parameter must be a hashref. The following keys
are recognized (unrecognized keys will be silently ignored).
"Allow_src"
By default, the scrubber won't be configured to allow constructs
that cause the browser to fetch things automatically, such as
"SRC" attributes in "IMG" tags. If this option is present and
true then those constructs will be allowed.
"Allow_href"
By default, the scrubber won't be configured to allow constructs
that cause the browser to fetch things if the user clicks on
something, such as the "HREF" attribute in "A" tags. Set this
option to a true value to allow this type of construct.
"Allow_a_mailto"
By default, the scrubber won't be configured to allow "MAILTO:"
URLs in "HREF" attributes in "A" tags. Set this option to a true
value to allow them. Ignored unless "Allow_href" is true.
"Whole_document"
By default, the scrubber will be configured to deal with a
snippet of HTML to be placed inside another document after
scrubbing, and won't allow "head" and "body" tags and so on.
Set this option to a true value if an entire HTML document is
being scrubbed.
"Block_tags"
If present, this must be an array ref holding a list of lower
case tag names. These tags will be removed from the allowed
list.
For example, a guestbook CGI that uses "HR" tags to separate
posts might wish to disallow the "HR" tag in posts, even though
"HR" presents no XSS hazard.
BUGS
* All scripting is safely removed, but no attempt is made to
ensure that there is a matching end tag for each start tag. That
could be a problem if the scrubbed HTML is to be inserted into a
larger HTML document, since "FONT" tags and so on could be
maliciously left open.
If that's a big problem for you, consider using the more
heavyweight (and probably much slower) HTML::StripScripts module
instead.
SEE ALSO
HTML::Scrubber, HTML::StripScripts
AUTHOR
Nick Cleaton
COPYRIGHT
Copyright (C) 2003 Nick Cleaton. All Rights Reserved.
This module is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.