Basically, browsers don't parse what should be valid URIs correctly, so
we have to go through some backbends to accomodate them. Specifically,
for browseable URIs, the following URIs have unintended behavior:
- ///example.com
- http:/example.com
- http:///example.com
Furthermore, if the path begins with //, modifying these URLs must
be done with care, as if you remove the host-name component, the
parse tree changes.
I've modified the engine to follow correct URI semantics as much
as possible while outputting browser compatible code, and invalidate
the URI in cases where we can't deal. There has been a refactoring
of URIScheme so that this important check is always performed,
introducing a new member variable allow_empty_host which is true
on data, file, mailto and news schemes.
This also fixes bypass bugs on URI.Munge.
Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
The new logic is as follows:
* Given a URL to insert into url(), check that it is properly URL
encoded (in particular, a doublequote and backslash never occurs
within it) and then place it as url("http://example.com").
* Given a font name, if it is strictly alphanumeric, it is safe to omit
quotes. Otherwise, wrap in double quotes and replace '"' with '\22 '
(note trailing space) and '\' with '\5C ' (ditto).
We introduce expandCSSEscape() which is a hack for common parsing
idioms in CSS; this means that CSS escapes are now recognized inside
URLs as well as unquoted font names.
Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
This fix is slightly hackish, as we simply treat comments as whitespace.
This should largely be correct, and breaks no current test cases,
although it could result in noncompliant behavior.
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
This commit is a limited implementation of the "active formatting
elements" algorithm implemented in HTML5, which preserves certain
formatting elements such as <a> and <b> when exiting or entering nodes.
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
The newest autoclose code uses the elements property in whether or not an
element should be closed by a particular tag. The heuristic is simple; if
the element doesn't allow that tag as a child, it closes the parent
container. This doesn't work, however, with <blockquote>, which while not
allowing inline styles under Strict doctypes, requires them to be passed
through MakeWellFormed.
The fix was to transition MakeWellFormed to call a method to retrieve the
elements, and then have StrictBlockquote implement a special version of
this method. Future versions of HTML Purifier may be more flexible in this
regard--further study of the HTML5 specification is required.
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
HTMLT tests are a compact and easy-to-use way of making assertPurification
type tests. They take the format of:
--INI--
Ns.Directive = "directive value"
--HTML--
Input HTML
--EXPECT--
Expected HTML
Expect more features and migration to be coming soon.
Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
