update HTMLPurifier; enable embedded flash video in articles

lib/htmlpurifier/library/HTMLPurifier/AttrDef.php

@@ -82,6 +82,42 @@ abstract class HTMLPurifier_AttrDef
         return preg_replace('/rgb\((\d+)\s*,\s*(\d+)\s*,\s*(\d+)\)/', 'rgb(\1,\2,\3)', $string);
     }
 
+    /**
+     * Parses a possibly escaped CSS string and returns the "pure" 
+     * version of it.
+     */
+    protected function expandCSSEscape($string) {
+        // flexibly parse it
+        $ret = '';
+        for ($i = 0, $c = strlen($string); $i < $c; $i++) {
+            if ($string[$i] === '\\') {
+                $i++;
+                if ($i >= $c) {
+                    $ret .= '\\';
+                    break;
+                }
+                if (ctype_xdigit($string[$i])) {
+                    $code = $string[$i];
+                    for ($a = 1, $i++; $i < $c && $a < 6; $i++, $a++) {
+                        if (!ctype_xdigit($string[$i])) break;
+                        $code .= $string[$i];
+                    }
+                    // We have to be extremely careful when adding
+                    // new characters, to make sure we're not breaking
+                    // the encoding.
+                    $char = HTMLPurifier_Encoder::unichr(hexdec($code));
+                    if (HTMLPurifier_Encoder::cleanUTF8($char) === '') continue;
+                    $ret .= $char;
+                    if ($i < $c && trim($string[$i]) !== '') $i--;
+                    continue;
+                }
+                if ($string[$i] === "\n") continue;
+            }
+            $ret .= $string[$i];
+        }
+        return $ret;
+    }
+
 }
 
 // vim: et sw=4 sts=4

lib/htmlpurifier/library/HTMLPurifier/AttrDef/CSS/BackgroundPosition.php

@@ -59,7 +59,8 @@ class HTMLPurifier_AttrDef_CSS_BackgroundPosition extends HTMLPurifier_AttrDef
         $keywords = array();
         $keywords['h'] = false; // left, right
         $keywords['v'] = false; // top, bottom
-        $keywords['c'] = false; // center
+        $keywords['ch'] = false; // center (first word)
+        $keywords['cv'] = false; // center (second word)
         $measures = array();
 
         $i = 0;
@@ -79,6 +80,13 @@ class HTMLPurifier_AttrDef_CSS_BackgroundPosition extends HTMLPurifier_AttrDef
             $lbit = ctype_lower($bit) ? $bit : strtolower($bit);
             if (isset($lookup[$lbit])) {
                 $status = $lookup[$lbit];
+                if ($status == 'c') {
+                    if ($i == 0) {
+                        $status = 'ch';
+                    } else {
+                        $status = 'cv';
+                    }
+                }
                 $keywords[$status] = $lbit;
                 $i++;
             }
@@ -101,20 +109,19 @@ class HTMLPurifier_AttrDef_CSS_BackgroundPosition extends HTMLPurifier_AttrDef
 
         if (!$i) return false; // no valid values were caught
 
-
         $ret = array();
 
         // first keyword
         if     ($keywords['h'])     $ret[] = $keywords['h'];
-        elseif (count($measures))   $ret[] = array_shift($measures);
-        elseif ($keywords['c']) {
-            $ret[] = $keywords['c'];
-            $keywords['c'] = false; // prevent re-use: center = center center
+        elseif ($keywords['ch']) {
+            $ret[] = $keywords['ch'];
+            $keywords['cv'] = false; // prevent re-use: center = center center
         }
+        elseif (count($measures))   $ret[] = array_shift($measures);
 
         if     ($keywords['v'])     $ret[] = $keywords['v'];
+        elseif ($keywords['cv'])    $ret[] = $keywords['cv'];
         elseif (count($measures))   $ret[] = array_shift($measures);
-        elseif ($keywords['c'])     $ret[] = $keywords['c'];
 
         if (empty($ret)) return false;
         return implode(' ', $ret);

lib/htmlpurifier/library/HTMLPurifier/AttrDef/CSS/Color.php

@@ -9,7 +9,7 @@ class HTMLPurifier_AttrDef_CSS_Color extends HTMLPurifier_AttrDef
     public function validate($color, $config, $context) {
 
         static $colors = null;
-        if ($colors === null) $colors = $config->get('Core', 'ColorKeywords');
+        if ($colors === null) $colors = $config->get('Core.ColorKeywords');
 
         $color = trim($color);
         if ($color === '') return false;

lib/htmlpurifier/library/HTMLPurifier/AttrDef/CSS/FontFamily.php

@@ -2,11 +2,43 @@
 
 /**
  * Validates a font family list according to CSS spec
- * @todo whitelisting allowed fonts would be nice
  */
 class HTMLPurifier_AttrDef_CSS_FontFamily extends HTMLPurifier_AttrDef
 {
 
+    protected $mask = null;
+
+    public function __construct() {
+        $this->mask = '- ';
+        for ($c = 'a'; $c <= 'z'; $c++) $this->mask .= $c;
+        for ($c = 'A'; $c <= 'Z'; $c++) $this->mask .= $c;
+        for ($c = '0'; $c <= '9'; $c++) $this->mask .= $c; // cast-y, but should be fine
+        // special bytes used by UTF-8
+        for ($i = 0x80; $i <= 0xFF; $i++) {
+            // We don't bother excluding invalid bytes in this range,
+            // because the our restriction of well-formed UTF-8 will
+            // prevent these from ever occurring.
+            $this->mask .= chr($i);
+        }
+
+        /*
+            PHP's internal strcspn implementation is
+            O(length of string * length of mask), making it inefficient
+            for large masks.  However, it's still faster than
+            preg_match 8)
+          for (p = s1;;) {
+            spanp = s2;
+            do {
+              if (*spanp == c || p == s1_end) {
+                return p - s1;
+              }
+            } while (spanp++ < (s2_end - 1));
+            c = *++p;
+          }
+         */
+        // possible optimization: invert the mask.
+    }
+
     public function validate($string, $config, $context) {
         static $generic_names = array(
             'serif' => true,
@@ -15,6 +47,7 @@ class HTMLPurifier_AttrDef_CSS_FontFamily extends HTMLPurifier_AttrDef
             'fantasy' => true,
             'cursive' => true
         );
+        $allowed_fonts = $config->get('CSS.AllowedFonts');
 
         // assume that no font names contain commas in them
         $fonts = explode(',', $string);
@@ -24,7 +57,9 @@ class HTMLPurifier_AttrDef_CSS_FontFamily extends HTMLPurifier_AttrDef
             if ($font === '') continue;
             // match a generic name
             if (isset($generic_names[$font])) {
-                $final .= $font . ', ';
+                if ($allowed_fonts === null || isset($allowed_fonts[$font])) {
+                    $final .= $font . ', ';
+                }
                 continue;
             }
             // match a quoted name
@@ -34,50 +69,122 @@ class HTMLPurifier_AttrDef_CSS_FontFamily extends HTMLPurifier_AttrDef
                 $quote = $font[0];
                 if ($font[$length - 1] !== $quote) continue;
                 $font = substr($font, 1, $length - 2);
-
-                $new_font = '';
-                for ($i = 0, $c = strlen($font); $i < $c; $i++) {
-                    if ($font[$i] === '\\') {
-                        $i++;
-                        if ($i >= $c) {
-                            $new_font .= '\\';
-                            break;
-                        }
-                        if (ctype_xdigit($font[$i])) {
-                            $code = $font[$i];
-                            for ($a = 1, $i++; $i < $c && $a < 6; $i++, $a++) {
-                                if (!ctype_xdigit($font[$i])) break;
-                                $code .= $font[$i];
-                            }
-                            // We have to be extremely careful when adding
-                            // new characters, to make sure we're not breaking
-                            // the encoding.
-                            $char = HTMLPurifier_Encoder::unichr(hexdec($code));
-                            if (HTMLPurifier_Encoder::cleanUTF8($char) === '') continue;
-                            $new_font .= $char;
-                            if ($i < $c && trim($font[$i]) !== '') $i--;
-                            continue;
-                        }
-                        if ($font[$i] === "\n") continue;
-                    }
-                    $new_font .= $font[$i];
-                }
-
-                $font = $new_font;
             }
+
+            $font = $this->expandCSSEscape($font);
+
             // $font is a pure representation of the font name
 
+            if ($allowed_fonts !== null && !isset($allowed_fonts[$font])) {
+                continue;
+            }
+
             if (ctype_alnum($font) && $font !== '') {
                 // very simple font, allow it in unharmed
                 $final .= $font . ', ';
                 continue;
             }
 
-            // complicated font, requires quoting
+            // bugger out on whitespace.  form feed (0C) really
+            // shouldn't show up regardless
+            $font = str_replace(array("\n", "\t", "\r", "\x0C"), ' ', $font);
 
-            // armor single quotes and new lines
-            $font = str_replace("\\", "\\\\", $font);
-            $font = str_replace("'", "\\'", $font);
+            // Here, there are various classes of characters which need
+            // to be treated differently:
+            //  - Alphanumeric characters are essentially safe.  We
+            //    handled these above.
+            //  - Spaces require quoting, though most parsers will do
+            //    the right thing if there aren't any characters that
+            //    can be misinterpreted
+            //  - Dashes rarely occur, but they fairly unproblematic
+            //    for parsing/rendering purposes.
+            //  The above characters cover the majority of Western font
+            //  names.
+            //  - Arbitrary Unicode characters not in ASCII.  Because
+            //    most parsers give little thought to Unicode, treatment
+            //    of these codepoints is basically uniform, even for
+            //    punctuation-like codepoints.  These characters can
+            //    show up in non-Western pages and are supported by most
+            //    major browsers, for example: "ＭＳ 明朝" is a
+            //    legitimate font-name
+            //    <http://ja.wikipedia.org/wiki/MS_明朝>.  See
+            //    the CSS3 spec for more examples:
+            //    <http://www.w3.org/TR/2011/WD-css3-fonts-20110324/localizedfamilynames.png>
+            //    You can see live samples of these on the Internet:
+            //    <http://www.google.co.jp/search?q=font-family+ＭＳ+明朝|ゴシック>
+            //    However, most of these fonts have ASCII equivalents:
+            //    for example, 'MS Mincho', and it's considered
+            //    professional to use ASCII font names instead of
+            //    Unicode font names.  Thanks Takeshi Terada for
+            //    providing this information.
+            //  The following characters, to my knowledge, have not been
+            //  used to name font names.
+            //  - Single quote.  While theoretically you might find a
+            //    font name that has a single quote in its name (serving
+            //    as an apostrophe, e.g. Dave's Scribble), I haven't
+            //    been able to find any actual examples of this.
+            //    Internet Explorer's cssText translation (which I
+            //    believe is invoked by innerHTML) normalizes any
+            //    quoting to single quotes, and fails to escape single
+            //    quotes.  (Note that this is not IE's behavior for all
+            //    CSS properties, just some sort of special casing for
+            //    font-family).  So a single quote *cannot* be used
+            //    safely in the font-family context if there will be an
+            //    innerHTML/cssText translation.  Note that Firefox 3.x
+            //    does this too.
+            //  - Double quote.  In IE, these get normalized to
+            //    single-quotes, no matter what the encoding.  (Fun
+            //    fact, in IE8, the 'content' CSS property gained
+            //    support, where they special cased to preserve encoded
+            //    double quotes, but still translate unadorned double
+            //    quotes into single quotes.)  So, because their
+            //    fixpoint behavior is identical to single quotes, they
+            //    cannot be allowed either.  Firefox 3.x displays
+            //    single-quote style behavior.
+            //  - Backslashes are reduced by one (so \\ -> \) every
+            //    iteration, so they cannot be used safely.  This shows
+            //    up in IE7, IE8 and FF3
+            //  - Semicolons, commas and backticks are handled properly.
+            //  - The rest of the ASCII punctuation is handled properly.
+            // We haven't checked what browsers do to unadorned
+            // versions, but this is not important as long as the
+            // browser doesn't /remove/ surrounding quotes (as IE does
+            // for HTML).
+            //
+            // With these results in hand, we conclude that there are
+            // various levels of safety:
+            //  - Paranoid: alphanumeric, spaces and dashes(?)
+            //  - International: Paranoid + non-ASCII Unicode
+            //  - Edgy: Everything except quotes, backslashes
+            //  - NoJS: Standards compliance, e.g. sod IE. Note that
+            //    with some judicious character escaping (since certain
+            //    types of escaping doesn't work) this is theoretically
+            //    OK as long as innerHTML/cssText is not called.
+            // We believe that international is a reasonable default
+            // (that we will implement now), and once we do more
+            // extensive research, we may feel comfortable with dropping
+            // it down to edgy.
+
+            // Edgy: alphanumeric, spaces, dashes and Unicode.  Use of
+            // str(c)spn assumes that the string was already well formed
+            // Unicode (which of course it is).
+            if (strspn($font, $this->mask) !== strlen($font)) {
+                continue;
+            }
+
+            // Historical:
+            // In the absence of innerHTML/cssText, these ugly
+            // transforms don't pose a security risk (as \\ and \"
+            // might--these escapes are not supported by most browsers).
+            // We could try to be clever and use single-quote wrapping
+            // when there is a double quote present, but I have choosen
+            // not to implement that.  (NOTE: you can reduce the amount
+            // of escapes by one depending on what quoting style you use)
+            // $font = str_replace('\\', '\\5C ', $font);
+            // $font = str_replace('"',  '\\22 ', $font);
+            // $font = str_replace("'",  '\\27 ', $font);
+
+            // font possibly with spaces, requires quoting
             $final .= "'$font', ";
         }
         $final = rtrim($final, ', ');

lib/htmlpurifier/library/HTMLPurifier/AttrDef/CSS/URI.php

@@ -34,20 +34,25 @@ class HTMLPurifier_AttrDef_CSS_URI extends HTMLPurifier_AttrDef_URI
             $uri = substr($uri, 1, $new_length - 1);
         }
 
-        $keys   = array(  '(',   ')',   ',',   ' ',   '"',   "'");
-        $values = array('\\(', '\\)', '\\,', '\\ ', '\\"', "\\'");
-        $uri = str_replace($values, $keys, $uri);
+        $uri = $this->expandCSSEscape($uri);
 
         $result = parent::validate($uri, $config, $context);
 
         if ($result === false) return false;
 
-        // escape necessary characters according to CSS spec
-        // except for the comma, none of these should appear in the
-        // URI at all
-        $result = str_replace($keys, $values, $result);
+        // extra sanity check; should have been done by URI
+        $result = str_replace(array('"', "\\", "\n", "\x0c", "\r"), "", $result);
 
-        return "url($result)";
+        // suspicious characters are ()'; we're going to percent encode
+        // them for safety.
+        $result = str_replace(array('(', ')', "'"), array('%28', '%29', '%27'), $result);
+
+        // there's an extra bug where ampersands lose their escaping on
+        // an innerHTML cycle, so a very unlucky query parameter could
+        // then change the meaning of the URL.  Unfortunately, there's
+        // not much we can do about that...
+
+        return "url(\"$result\")";
 
     }
 

lib/htmlpurifier/library/HTMLPurifier/AttrDef/HTML/Class.php

@@ -0,0 +1,34 @@
+<?php
+
+/**
+ * Implements special behavior for class attribute (normally NMTOKENS)
+ */
+class HTMLPurifier_AttrDef_HTML_Class extends HTMLPurifier_AttrDef_HTML_Nmtokens
+{
+    protected function split($string, $config, $context) {
+        // really, this twiddle should be lazy loaded
+        $name = $config->getDefinition('HTML')->doctype->name;
+        if ($name == "XHTML 1.1" || $name == "XHTML 2.0") {
+            return parent::split($string, $config, $context);
+        } else {
+            return preg_split('/\s+/', $string);
+        }
+    }
+    protected function filter($tokens, $config, $context) {
+        $allowed = $config->get('Attr.AllowedClasses');
+        $forbidden = $config->get('Attr.ForbiddenClasses');
+        $ret = array();
+        foreach ($tokens as $token) {
+            if (
+                ($allowed === null || isset($allowed[$token])) &&
+                !isset($forbidden[$token]) &&
+                // We need this O(n) check because of PHP's array
+                // implementation that casts -0 to 0.
+                !in_array($token, $ret, true)
+            ) {
+                $ret[] = $token;
+            }
+        }
+        return $ret;
+    }
+}

lib/htmlpurifier/library/HTMLPurifier/AttrDef/HTML/Color.php

@@ -9,7 +9,7 @@ class HTMLPurifier_AttrDef_HTML_Color extends HTMLPurifier_AttrDef
     public function validate($string, $config, $context) {
 
         static $colors = null;
-        if ($colors === null) $colors = $config->get('Core', 'ColorKeywords');
+        if ($colors === null) $colors = $config->get('Core.ColorKeywords');
 
         $string = trim($string);
 

lib/htmlpurifier/library/HTMLPurifier/AttrDef/HTML/FrameTarget.php

@@ -12,7 +12,7 @@ class HTMLPurifier_AttrDef_HTML_FrameTarget extends HTMLPurifier_AttrDef_Enum
     public function __construct() {}
 
     public function validate($string, $config, $context) {
-        if ($this->valid_values === false) $this->valid_values = $config->get('Attr', 'AllowedFrameTargets');
+        if ($this->valid_values === false) $this->valid_values = $config->get('Attr.AllowedFrameTargets');
         return parent::validate($string, $config, $context);
     }
 

lib/htmlpurifier/library/HTMLPurifier/AttrDef/HTML/ID.php

@@ -17,18 +17,18 @@ class HTMLPurifier_AttrDef_HTML_ID extends HTMLPurifier_AttrDef
 
     public function validate($id, $config, $context) {
 
-        if (!$config->get('Attr', 'EnableID')) return false;
+        if (!$config->get('Attr.EnableID')) return false;
 
         $id = trim($id); // trim it first
 
         if ($id === '') return false;
 
-        $prefix = $config->get('Attr', 'IDPrefix');
+        $prefix = $config->get('Attr.IDPrefix');
         if ($prefix !== '') {
-            $prefix .= $config->get('Attr', 'IDPrefixLocal');
+            $prefix .= $config->get('Attr.IDPrefixLocal');
             // prevent re-appending the prefix
             if (strpos($id, $prefix) !== 0) $id = $prefix . $id;
-        } elseif ($config->get('Attr', 'IDPrefixLocal') !== '') {
+        } elseif ($config->get('Attr.IDPrefixLocal') !== '') {
             trigger_error('%Attr.IDPrefixLocal cannot be used unless '.
                 '%Attr.IDPrefix is set', E_USER_WARNING);
         }
@@ -51,7 +51,7 @@ class HTMLPurifier_AttrDef_HTML_ID extends HTMLPurifier_AttrDef
             $result = ($trim === '');
         }
 
-        $regexp = $config->get('Attr', 'IDBlacklistRegexp');
+        $regexp = $config->get('Attr.IDBlacklistRegexp');
         if ($regexp && preg_match($regexp, $id)) {
             return false;
         }

lib/htmlpurifier/library/HTMLPurifier/AttrDef/HTML/LinkTypes.php

@@ -27,7 +27,7 @@ class HTMLPurifier_AttrDef_HTML_LinkTypes extends HTMLPurifier_AttrDef
 
     public function validate($string, $config, $context) {
 
-        $allowed = $config->get('Attr', $this->name);
+        $allowed = $config->get('Attr.' . $this->name);
         if (empty($allowed)) return false;
 
         $string = $this->parseCDATA($string);

lib/htmlpurifier/library/HTMLPurifier/AttrDef/HTML/Nmtokens.php

@@ -2,10 +2,6 @@
 
 /**
  * Validates contents based on NMTOKENS attribute type.
- * @note The only current use for this is the class attribute in HTML
- * @note Could have some functionality factored out into Nmtoken class
- * @warning We cannot assume this class will be used only for 'class'
- *          attributes. Not sure how to hook in magic behavior, then.
  */
 class HTMLPurifier_AttrDef_HTML_Nmtokens extends HTMLPurifier_AttrDef
 {
@@ -17,6 +13,17 @@ class HTMLPurifier_AttrDef_HTML_Nmtokens extends HTMLPurifier_AttrDef
         // early abort: '' and '0' (strings that convert to false) are invalid
         if (!$string) return false;
 
+        $tokens = $this->split($string, $config, $context);
+        $tokens = $this->filter($tokens, $config, $context);
+        if (empty($tokens)) return false;
+        return implode(' ', $tokens);
+
+    }
+
+    /**
+     * Splits a space separated list of tokens into its constituent parts.
+     */
+    protected function split($string, $config, $context) {
         // OPTIMIZABLE!
         // do the preg_match, capture all subpatterns for reformulation
 
@@ -24,23 +31,20 @@ class HTMLPurifier_AttrDef_HTML_Nmtokens extends HTMLPurifier_AttrDef
         // escaping because I don't know how to do that with regexps
         // and plus it would complicate optimization efforts (you never
         // see that anyway).
-        $matches = array();
         $pattern = '/(?:(?<=\s)|\A)'. // look behind for space or string start
                    '((?:--|-?[A-Za-z_])[A-Za-z_\-0-9]*)'.
                    '(?:(?=\s)|\z)/'; // look ahead for space or string end
         preg_match_all($pattern, $string, $matches);
+        return $matches[1];
+    }
 
-        if (empty($matches[1])) return false;
-
-        // reconstruct string
-        $new_string = '';
-        foreach ($matches[1] as $token) {
-            $new_string .= $token . ' ';
-        }
-        $new_string = rtrim($new_string);
-
-        return $new_string;
-
+    /**
+     * Template method for removing certain tokens based on arbitrary criteria.
+     * @note If we wanted to be really functional, we'd do an array_filter
+     *       with a callback. But... we're not.
+     */
+    protected function filter($tokens, $config, $context) {
+        return $tokens;
     }
 
 }

lib/htmlpurifier/library/HTMLPurifier/AttrDef/URI.php

@@ -25,7 +25,7 @@ class HTMLPurifier_AttrDef_URI extends HTMLPurifier_AttrDef
 
     public function validate($uri, $config, $context) {
 
-        if ($config->get('URI', 'Disable')) return false;
+        if ($config->get('URI.Disable')) return false;
 
         $uri = $this->parseCDATA($uri);
 

lib/htmlpurifier/library/HTMLPurifier/AttrDef/URI/Host.php

@@ -23,6 +23,12 @@ class HTMLPurifier_AttrDef_URI_Host extends HTMLPurifier_AttrDef
 
     public function validate($string, $config, $context) {
         $length = strlen($string);
+        // empty hostname is OK; it's usually semantically equivalent:
+        // the default host as defined by a URI scheme is used:
+        //
+        //      If the URI scheme defines a default for host, then that
+        //      default applies when the host subcomponent is undefined
+        //      or when the registered name is empty (zero length).
         if ($string === '') return '';
         if ($length > 1 && $string[0] === '[' && $string[$length-1] === ']') {
             //IPv6

lib/htmlpurifier/library/HTMLPurifier/AttrTransform/BdoDir.php

@@ -10,7 +10,7 @@ class HTMLPurifier_AttrTransform_BdoDir extends HTMLPurifier_AttrTransform
 
     public function transform($attr, $config, $context) {
         if (isset($attr['dir'])) return $attr;
-        $attr['dir'] = $config->get('Attr', 'DefaultTextDir');
+        $attr['dir'] = $config->get('Attr.DefaultTextDir');
         return $attr;
     }
 

lib/htmlpurifier/library/HTMLPurifier/AttrTransform/ImgRequired.php

@@ -15,21 +15,22 @@ class HTMLPurifier_AttrTransform_ImgRequired extends HTMLPurifier_AttrTransform
 
         $src = true;
         if (!isset($attr['src'])) {
-            if ($config->get('Core', 'RemoveInvalidImg')) return $attr;
-            $attr['src'] = $config->get('Attr', 'DefaultInvalidImage');
+            if ($config->get('Core.RemoveInvalidImg')) return $attr;
+            $attr['src'] = $config->get('Attr.DefaultInvalidImage');
             $src = false;
         }
 
         if (!isset($attr['alt'])) {
             if ($src) {
-                $alt = $config->get('Attr', 'DefaultImageAlt');
+                $alt = $config->get('Attr.DefaultImageAlt');
                 if ($alt === null) {
-                    $attr['alt'] = basename($attr['src']);
+                    // truncate if the alt is too long
+                    $attr['alt'] = substr(basename($attr['src']),0,40);
                 } else {
                     $attr['alt'] = $alt;
                 }
             } else {
-                $attr['alt'] = $config->get('Attr', 'DefaultInvalidImageAlt');
+                $attr['alt'] = $config->get('Attr.DefaultInvalidImageAlt');
             }
         }
 

lib/htmlpurifier/library/HTMLPurifier/AttrTransform/Name.php

@@ -7,6 +7,8 @@ class HTMLPurifier_AttrTransform_Name extends HTMLPurifier_AttrTransform
 {
 
     public function transform($attr, $config, $context) {
+        // Abort early if we're using relaxed definition of name
+        if ($config->get('HTML.Attr.Name.UseCDATA')) return $attr;
         if (!isset($attr['name'])) return $attr;
         $id = $this->confiscateAttr($attr, 'name');
         if ( isset($attr['id']))   return $attr;

lib/htmlpurifier/library/HTMLPurifier/AttrTransform/NameSync.php

@@ -0,0 +1,27 @@
+<?php
+
+/**
+ * Post-transform that performs validation to the name attribute; if
+ * it is present with an equivalent id attribute, it is passed through;
+ * otherwise validation is performed.
+ */
+class HTMLPurifier_AttrTransform_NameSync extends HTMLPurifier_AttrTransform
+{
+
+    public function __construct() {
+        $this->idDef = new HTMLPurifier_AttrDef_HTML_ID();
+    }
+
+    public function transform($attr, $config, $context) {
+        if (!isset($attr['name'])) return $attr;
+        $name = $attr['name'];
+        if (isset($attr['id']) && $attr['id'] === $name) return $attr;
+        $result = $this->idDef->validate($name, $config, $context);
+        if ($result === false) unset($attr['name']);
+        else $attr['name'] = $result;
+        return $attr;
+    }
+
+}
+
+// vim: et sw=4 sts=4

lib/htmlpurifier/library/HTMLPurifier/AttrTransform/Nofollow.php

@@ -0,0 +1,41 @@
+<?php
+
+// must be called POST validation
+
+/**
+ * Adds rel="nofollow" to all outbound links.  This transform is
+ * only attached if Attr.Nofollow is TRUE.
+ */
+class HTMLPurifier_AttrTransform_Nofollow extends HTMLPurifier_AttrTransform
+{
+    private $parser;
+
+    public function __construct() {
+        $this->parser = new HTMLPurifier_URIParser();
+    }
+
+    public function transform($attr, $config, $context) {
+
+        if (!isset($attr['href'])) {
+            return $attr;
+        }
+
+        // XXX Kind of inefficient
+        $url = $this->parser->parse($attr['href']);
+        $scheme = $url->getSchemeObj($config, $context);
+
+        if (!is_null($url->host) && $scheme !== false && $scheme->browsable) {
+            if (isset($attr['rel'])) {
+                $attr['rel'] .= ' nofollow';
+            } else {
+                $attr['rel'] = 'nofollow';
+            }
+        }
+
+        return $attr;
+
+    }
+
+}
+
+// vim: et sw=4 sts=4

lib/htmlpurifier/library/HTMLPurifier/AttrTransform/SafeParam.php

@@ -19,6 +19,7 @@ class HTMLPurifier_AttrTransform_SafeParam extends HTMLPurifier_AttrTransform
 
     public function __construct() {
         $this->uri = new HTMLPurifier_AttrDef_URI(true); // embedded
+        $this->wmode = new HTMLPurifier_AttrDef_Enum(array('window', 'opaque', 'transparent'));
     }
 
     public function transform($attr, $config, $context) {
@@ -33,12 +34,25 @@ class HTMLPurifier_AttrTransform_SafeParam extends HTMLPurifier_AttrTransform
             case 'allowNetworking':
                 $attr['value'] = 'internal';
                 break;
+            case 'allowFullScreen':
+                if ($config->get('HTML.FlashAllowFullScreen')) {
+                    $attr['value'] = ($attr['value'] == 'true') ? 'true' : 'false';
+                } else {
+                    $attr['value'] = 'false';
+                }
+                break;
             case 'wmode':
-                $attr['value'] = 'window';
+                $attr['value'] = $this->wmode->validate($attr['value'], $config, $context);
                 break;
             case 'movie':
+            case 'src':
+                $attr['name'] = "movie";
                 $attr['value'] = $this->uri->validate($attr['value'], $config, $context);
                 break;
+            case 'flashvars':
+                // we're going to allow arbitrary inputs to the SWF, on
+                // the reasoning that it could only hack the SWF, not us.
+                break;
             // add other cases to support other param name/value pairs
             default:
                 $attr['name'] = $attr['value'] = null;

lib/htmlpurifier/library/HTMLPurifier/AttrTypes.php

@@ -36,6 +36,9 @@ class HTMLPurifier_AttrTypes
         $this->info['Charsets'] = new HTMLPurifier_AttrDef_Text();
         $this->info['Character'] = new HTMLPurifier_AttrDef_Text();
 
+        // "proprietary" types
+        $this->info['Class'] = new HTMLPurifier_AttrDef_HTML_Class();
+
         // number is really a positive integer (one or more digits)
         // FIXME: ^^ not always, see start and value of list items
         $this->info['Number']   = new HTMLPurifier_AttrDef_Integer(false, false, true);

lib/htmlpurifier/library/HTMLPurifier/Bootstrap.php

@@ -37,7 +37,12 @@ class HTMLPurifier_Bootstrap
     public static function autoload($class) {
         $file = HTMLPurifier_Bootstrap::getPath($class);
         if (!$file) return false;
-        require HTMLPURIFIER_PREFIX . '/' . $file;
+        // Technically speaking, it should be ok and more efficient to
+        // just do 'require', but Antonio Parraga reports that with
+        // Zend extensions such as Zend debugger and APC, this invariant
+        // may be broken.  Since we have efficient alternatives, pay
+        // the cost here and avoid the bug.
+        require_once HTMLPURIFIER_PREFIX . '/' . $file;
         return true;
     }
 
@@ -65,10 +70,11 @@ class HTMLPurifier_Bootstrap
         if ( ($funcs = spl_autoload_functions()) === false ) {
             spl_autoload_register($autoload);
         } elseif (function_exists('spl_autoload_unregister')) {
+            $buggy  = version_compare(PHP_VERSION, '5.2.11', '<');
             $compat = version_compare(PHP_VERSION, '5.1.2', '<=') &&
                       version_compare(PHP_VERSION, '5.1.0', '>=');
             foreach ($funcs as $func) {
-                if (is_array($func)) {
+                if ($buggy && is_array($func)) {
                     // :TRICKY: There are some compatibility issues and some
                     // places where we need to error out
                     $reflector = new ReflectionMethod($func[0], $func[1]);

lib/htmlpurifier/library/HTMLPurifier/CSSDefinition.php

@@ -154,7 +154,7 @@ class HTMLPurifier_CSSDefinition extends HTMLPurifier_Definition
             new HTMLPurifier_AttrDef_CSS_Percentage(true),
             new HTMLPurifier_AttrDef_Enum(array('auto'))
         ));
-        $max = $config->get('CSS', 'MaxImgLength');
+        $max = $config->get('CSS.MaxImgLength');
 
         $this->info['width'] =
         $this->info['height'] =
@@ -211,15 +211,19 @@ class HTMLPurifier_CSSDefinition extends HTMLPurifier_Definition
         // partial support
         $this->info['white-space'] = new HTMLPurifier_AttrDef_Enum(array('nowrap'));
 
-        if ($config->get('CSS', 'Proprietary')) {
+        if ($config->get('CSS.Proprietary')) {
             $this->doSetupProprietary($config);
         }
 
-        if ($config->get('CSS', 'AllowTricky')) {
+        if ($config->get('CSS.AllowTricky')) {
             $this->doSetupTricky($config);
         }
 
-        $allow_important = $config->get('CSS', 'AllowImportant');
+        if ($config->get('CSS.Trusted')) {
+            $this->doSetupTrusted($config);
+        }
+
+        $allow_important = $config->get('CSS.AllowImportant');
         // wrap all attr-defs with decorator that handles !important
         foreach ($this->info as $k => $v) {
             $this->info[$k] = new HTMLPurifier_AttrDef_CSS_ImportantDecorator($v, $allow_important);
@@ -260,6 +264,23 @@ class HTMLPurifier_CSSDefinition extends HTMLPurifier_Definition
         $this->info['overflow'] = new HTMLPurifier_AttrDef_Enum(array('visible', 'hidden', 'auto', 'scroll'));
     }
 
+    protected function doSetupTrusted($config) {
+        $this->info['position'] = new HTMLPurifier_AttrDef_Enum(array(
+            'static', 'relative', 'absolute', 'fixed'
+        ));
+        $this->info['top'] =
+        $this->info['left'] =
+        $this->info['right'] =
+        $this->info['bottom'] = new HTMLPurifier_AttrDef_CSS_Composite(array(
+            new HTMLPurifier_AttrDef_CSS_Length(),
+            new HTMLPurifier_AttrDef_CSS_Percentage(),
+            new HTMLPurifier_AttrDef_Enum(array('auto')),
+        ));
+        $this->info['z-index'] = new HTMLPurifier_AttrDef_CSS_Composite(array(
+            new HTMLPurifier_AttrDef_Integer(),
+            new HTMLPurifier_AttrDef_Enum(array('auto')),
+        ));
+    }
 
     /**
      * Performs extra config-based processing. Based off of
@@ -272,20 +293,29 @@ class HTMLPurifier_CSSDefinition extends HTMLPurifier_Definition
         // setup allowed elements
         $support = "(for information on implementing this, see the ".
                    "support forums) ";
-        $allowed_attributes = $config->get('CSS', 'AllowedProperties');
-        if ($allowed_attributes !== null) {
+        $allowed_properties = $config->get('CSS.AllowedProperties');
+        if ($allowed_properties !== null) {
             foreach ($this->info as $name => $d) {
-                if(!isset($allowed_attributes[$name])) unset($this->info[$name]);
-                unset($allowed_attributes[$name]);
+                if(!isset($allowed_properties[$name])) unset($this->info[$name]);
+                unset($allowed_properties[$name]);
             }
             // emit errors
-            foreach ($allowed_attributes as $name => $d) {
+            foreach ($allowed_properties as $name => $d) {
                 // :TODO: Is this htmlspecialchars() call really necessary?
                 $name = htmlspecialchars($name);
                 trigger_error("Style attribute '$name' is not supported $support", E_USER_WARNING);
             }
         }
 
+        $forbidden_properties = $config->get('CSS.ForbiddenProperties');
+        if ($forbidden_properties !== null) {
+            foreach ($this->info as $name => $d) {
+                if (isset($forbidden_properties[$name])) {
+                    unset($this->info[$name]);
+                }
+            }
+        }
+
     }
 }
 

lib/htmlpurifier/library/HTMLPurifier/ChildDef/Required.php

@@ -59,7 +59,7 @@ class HTMLPurifier_ChildDef_Required extends HTMLPurifier_ChildDef
         $all_whitespace = true;
 
         // some configuration
-        $escape_invalid_children = $config->get('Core', 'EscapeInvalidChildren');
+        $escape_invalid_children = $config->get('Core.EscapeInvalidChildren');
 
         // generator
         $gen = new HTMLPurifier_Generator($config, $context);

lib/htmlpurifier/library/HTMLPurifier/Config.php

@@ -20,7 +20,7 @@ class HTMLPurifier_Config
     /**
      * HTML Purifier's version
      */
-    public $version = '3.3.0';
+    public $version = '4.3.0';
 
     /**
      * Bool indicator whether or not to automatically finalize
@@ -68,12 +68,31 @@ class HTMLPurifier_Config
      */
     protected $plist;
 
+    /**
+     * Whether or not a set is taking place due to an
+     * alias lookup.
+     */
+    private $aliasMode;
+
+    /**
+     * Set to false if you do not want line and file numbers in errors
+     * (useful when unit testing).  This will also compress some errors
+     * and exceptions.
+     */
+    public $chatty = true;
+
+    /**
+     * Current lock; only gets to this namespace are allowed.
+     */
+    private $lock;
+
     /**
      * @param $definition HTMLPurifier_ConfigSchema that defines what directives
      *                    are allowed.
      */
-    public function __construct($definition) {
-        $this->plist = new HTMLPurifier_PropertyList($definition->defaultPlist);
+    public function __construct($definition, $parent = null) {
+        $parent = $parent ? $parent : $definition->defaultPlist;
+        $this->plist = new HTMLPurifier_PropertyList($parent);
         $this->def = $definition; // keep a copy around for checking
         $this->parser = new HTMLPurifier_VarParser_Flexible();
     }
@@ -102,6 +121,16 @@ class HTMLPurifier_Config
         return $ret;
     }
 
+    /**
+     * Creates a new config object that inherits from a previous one.
+     * @param HTMLPurifier_Config $config Configuration object to inherit
+     *        from.
+     * @return HTMLPurifier_Config object with $config as its parent.
+     */
+    public static function inherit(HTMLPurifier_Config $config) {
+        return new HTMLPurifier_Config($config->def, $config->plist);
+    }
+
     /**
      * Convenience constructor that creates a default configuration object.
      * @return Default HTMLPurifier_Config object.
@@ -114,24 +143,34 @@ class HTMLPurifier_Config
 
     /**
      * Retreives a value from the configuration.
-     * @param $namespace String namespace
      * @param $key String key
      */
-    public function get($namespace, $key) {
-        if (!$this->finalized) $this->autoFinalize ? $this->finalize() : $this->plist->squash(true);
-        if (!isset($this->def->info[$namespace][$key])) {
+    public function get($key, $a = null) {
+        if ($a !== null) {
+            $this->triggerError("Using deprecated API: use \$config->get('$key.$a') instead", E_USER_WARNING);
+            $key = "$key.$a";
+        }
+        if (!$this->finalized) $this->autoFinalize();
+        if (!isset($this->def->info[$key])) {
             // can't add % due to SimpleTest bug
-            trigger_error('Cannot retrieve value of undefined directive ' . htmlspecialchars("$namespace.$key"),
+            $this->triggerError('Cannot retrieve value of undefined directive ' . htmlspecialchars($key),
                 E_USER_WARNING);
             return;
         }
-        if (isset($this->def->info[$namespace][$key]->isAlias)) {
-            $d = $this->def->info[$namespace][$key];
-            trigger_error('Cannot get value from aliased directive, use real name ' . $d->namespace . '.' . $d->name,
+        if (isset($this->def->info[$key]->isAlias)) {
+            $d = $this->def->info[$key];
+            $this->triggerError('Cannot get value from aliased directive, use real name ' . $d->key,
                 E_USER_ERROR);
             return;
         }
-        return $this->plist->get("$namespace.$key");
+        if ($this->lock) {
+            list($ns) = explode('.', $key);
+            if ($ns !== $this->lock) {
+                $this->triggerError('Cannot get value of namespace ' . $ns . ' when lock for ' . $this->lock . ' is active, this probably indicates a Definition setup method is accessing directives that are not within its namespace', E_USER_ERROR);
+                return;
+            }
+        }
+        return $this->plist->get($key);
     }
 
     /**
@@ -139,13 +178,13 @@ class HTMLPurifier_Config
      * @param $namespace String namespace
      */
     public function getBatch($namespace) {
-        if (!$this->finalized) $this->autoFinalize ? $this->finalize() : $this->plist->squash(true);
-        if (!isset($this->def->info[$namespace])) {
-            trigger_error('Cannot retrieve undefined namespace ' . htmlspecialchars($namespace),
+        if (!$this->finalized) $this->autoFinalize();
+        $full = $this->getAll();
+        if (!isset($full[$namespace])) {
+            $this->triggerError('Cannot retrieve undefined namespace ' . htmlspecialchars($namespace),
                 E_USER_WARNING);
             return;
         }
-        $full = $this->getAll();
         return $full[$namespace];
     }
 
@@ -178,9 +217,10 @@ class HTMLPurifier_Config
 
     /**
      * Retrieves all directives, organized by namespace
+     * @warning This is a pretty inefficient function, avoid if you can
      */
     public function getAll() {
-        if (!$this->finalized) $this->autoFinalize ? $this->finalize() : $this->plist->squash(true);
+        if (!$this->finalized) $this->autoFinalize();
         $ret = array();
         foreach ($this->plist->squash() as $name => $value) {
             list($ns, $key) = explode('.', $name, 2);
@@ -191,29 +231,37 @@ class HTMLPurifier_Config
 
     /**
      * Sets a value to configuration.
-     * @param $namespace String namespace
      * @param $key String key
      * @param $value Mixed value
      */
-    public function set($namespace, $key, $value, $from_alias = false) {
+    public function set($key, $value, $a = null) {
+        if (strpos($key, '.') === false) {
+            $namespace = $key;
+            $directive = $value;
+            $value = $a;
+            $key = "$key.$directive";
+            $this->triggerError("Using deprecated API: use \$config->set('$key', ...) instead", E_USER_NOTICE);
+        } else {
+            list($namespace) = explode('.', $key);
+        }
         if ($this->isFinalized('Cannot set directive after finalization')) return;
-        if (!isset($this->def->info[$namespace][$key])) {
-            trigger_error('Cannot set undefined directive ' . htmlspecialchars("$namespace.$key") . ' to value',
+        if (!isset($this->def->info[$key])) {
+            $this->triggerError('Cannot set undefined directive ' . htmlspecialchars($key) . ' to value',
                 E_USER_WARNING);
             return;
         }
-        $def = $this->def->info[$namespace][$key];
+        $def = $this->def->info[$key];
 
         if (isset($def->isAlias)) {
-            if ($from_alias) {
-                trigger_error('Double-aliases not allowed, please fix '.
-                    'ConfigSchema bug with' . "$namespace.$key", E_USER_ERROR);
+            if ($this->aliasMode) {
+                $this->triggerError('Double-aliases not allowed, please fix '.
+                    'ConfigSchema bug with' . $key, E_USER_ERROR);
                 return;
             }
-            $this->set($new_ns  = $def->namespace,
-                       $new_dir = $def->name,
-                       $value, true);
-            trigger_error("$namespace.$key is an alias, preferred directive name is $new_ns.$new_dir", E_USER_NOTICE);
+            $this->aliasMode = true;
+            $this->set($def->key, $value);
+            $this->aliasMode = false;
+            $this->triggerError("$key is an alias, preferred directive name is {$def->key}", E_USER_NOTICE);
             return;
         }
 
@@ -231,7 +279,7 @@ class HTMLPurifier_Config
         try {
             $value = $this->parser->parse($value, $type, $allow_null);
         } catch (HTMLPurifier_VarParserException $e) {
-            trigger_error('Value for ' . "$namespace.$key" . ' is of invalid type, should be ' . HTMLPurifier_VarParser::getTypeName($type), E_USER_WARNING);
+            $this->triggerError('Value for ' . $key . ' is of invalid type, should be ' . HTMLPurifier_VarParser::getTypeName($type), E_USER_WARNING);
             return;
         }
         if (is_string($value) && is_object($def)) {
@@ -241,17 +289,17 @@ class HTMLPurifier_Config
             }
             // check to see if the value is allowed
             if (isset($def->allowed) && !isset($def->allowed[$value])) {
-                trigger_error('Value not supported, valid values are: ' .
+                $this->triggerError('Value not supported, valid values are: ' .
                     $this->_listify($def->allowed), E_USER_WARNING);
                 return;
             }
         }
-        $this->plist->set("$namespace.$key", $value);
+        $this->plist->set($key, $value);
 
         // reset definitions if the directives they depend on changed
         // this is a very costly process, so it's discouraged
         // with finalization
-        if ($namespace == 'HTML' || $namespace == 'CSS') {
+        if ($namespace == 'HTML' || $namespace == 'CSS' || $namespace == 'URI') {
             $this->definitions[$namespace] = null;
         }
 
@@ -271,74 +319,203 @@ class HTMLPurifier_Config
      * Retrieves object reference to the HTML definition.
      * @param $raw Return a copy that has not been setup yet. Must be
      *             called before it's been setup, otherwise won't work.
+     * @param $optimized If true, this method may return null, to
+     *             indicate that a cached version of the modified
+     *             definition object is available and no further edits
+     *             are necessary.  Consider using
+     *             maybeGetRawHTMLDefinition, which is more explicitly
+     *             named, instead.
      */
-    public function getHTMLDefinition($raw = false) {
-        return $this->getDefinition('HTML', $raw);
+    public function getHTMLDefinition($raw = false, $optimized = false) {
+        return $this->getDefinition('HTML', $raw, $optimized);
     }
 
     /**
      * Retrieves object reference to the CSS definition
      * @param $raw Return a copy that has not been setup yet. Must be
      *             called before it's been setup, otherwise won't work.
+     * @param $optimized If true, this method may return null, to
+     *             indicate that a cached version of the modified
+     *             definition object is available and no further edits
+     *             are necessary.  Consider using
+     *             maybeGetRawCSSDefinition, which is more explicitly
+     *             named, instead.
      */
-    public function getCSSDefinition($raw = false) {
-        return $this->getDefinition('CSS', $raw);
+    public function getCSSDefinition($raw = false, $optimized = false) {
+        return $this->getDefinition('CSS', $raw, $optimized);
+    }
+
+    /**
+     * Retrieves object reference to the URI definition
+     * @param $raw Return a copy that has not been setup yet. Must be
+     *             called before it's been setup, otherwise won't work.
+     * @param $optimized If true, this method may return null, to
+     *             indicate that a cached version of the modified
+     *             definition object is available and no further edits
+     *             are necessary.  Consider using
+     *             maybeGetRawURIDefinition, which is more explicitly
+     *             named, instead.
+     */
+    public function getURIDefinition($raw = false, $optimized = false) {
+        return $this->getDefinition('URI', $raw, $optimized);
     }
 
     /**
      * Retrieves a definition
      * @param $type Type of definition: HTML, CSS, etc
      * @param $raw  Whether or not definition should be returned raw
+     * @param $optimized Only has an effect when $raw is true.  Whether
+     *        or not to return null if the result is already present in
+     *        the cache.  This is off by default for backwards
+     *        compatibility reasons, but you need to do things this
+     *        way in order to ensure that caching is done properly.
+     *        Check out enduser-customize.html for more details.
+     *        We probably won't ever change this default, as much as the
+     *        maybe semantics is the "right thing to do."
      */
-    public function getDefinition($type, $raw = false) {
-        if (!$this->finalized) $this->autoFinalize ? $this->finalize() : $this->plist->squash(true);
+    public function getDefinition($type, $raw = false, $optimized = false) {
+        if ($optimized && !$raw) {
+            throw new HTMLPurifier_Exception("Cannot set optimized = true when raw = false");
+        }
+        if (!$this->finalized) $this->autoFinalize();
+        // temporarily suspend locks, so we can handle recursive definition calls
+        $lock = $this->lock;
+        $this->lock = null;
         $factory = HTMLPurifier_DefinitionCacheFactory::instance();
         $cache = $factory->create($type, $this);
+        $this->lock = $lock;
         if (!$raw) {
-            // see if we can quickly supply a definition
+            // full definition
+            // ---------------
+            // check if definition is in memory
             if (!empty($this->definitions[$type])) {
-                if (!$this->definitions[$type]->setup) {
-                    $this->definitions[$type]->setup($this);
-                    $cache->set($this->definitions[$type], $this);
+                $def = $this->definitions[$type];
+                // check if the definition is setup
+                if ($def->setup) {
+                    return $def;
+                } else {
+                    $def->setup($this);
+                    if ($def->optimized) $cache->add($def, $this);
+                    return $def;
                 }
-                return $this->definitions[$type];
             }
-            // memory check missed, try cache
-            $this->definitions[$type] = $cache->get($this);
-            if ($this->definitions[$type]) {
-                // definition in cache, return it
-                return $this->definitions[$type];
+            // check if definition is in cache
+            $def = $cache->get($this);
+            if ($def) {
+                // definition in cache, save to memory and return it
+                $this->definitions[$type] = $def;
+                return $def;
             }
-        } elseif (
-            !empty($this->definitions[$type]) &&
-            !$this->definitions[$type]->setup
-        ) {
-            // raw requested, raw in memory, quick return
-            return $this->definitions[$type];
+            // initialize it
+            $def = $this->initDefinition($type);
+            // set it up
+            $this->lock = $type;
+            $def->setup($this);
+            $this->lock = null;
+            // save in cache
+            $cache->add($def, $this);
+            // return it
+            return $def;
+        } else {
+            // raw definition
+            // --------------
+            // check preconditions
+            $def = null;
+            if ($optimized) {
+                if (is_null($this->get($type . '.DefinitionID'))) {
+                    // fatally error out if definition ID not set
+                    throw new HTMLPurifier_Exception("Cannot retrieve raw version without specifying %$type.DefinitionID");
+                }
+            }
+            if (!empty($this->definitions[$type])) {
+                $def = $this->definitions[$type];
+                if ($def->setup && !$optimized) {
+                    $extra = $this->chatty ? " (try moving this code block earlier in your initialization)" : "";
+                    throw new HTMLPurifier_Exception("Cannot retrieve raw definition after it has already been setup" . $extra);
+                }
+                if ($def->optimized === null) {
+                    $extra = $this->chatty ? " (try flushing your cache)" : "";
+                    throw new HTMLPurifier_Exception("Optimization status of definition is unknown" . $extra);
+                }
+                if ($def->optimized !== $optimized) {
+                    $msg = $optimized ? "optimized" : "unoptimized";
+                    $extra = $this->chatty ? " (this backtrace is for the first inconsistent call, which was for a $msg raw definition)" : "";
+                    throw new HTMLPurifier_Exception("Inconsistent use of optimized and unoptimized raw definition retrievals" . $extra);
+                }
+            }
+            // check if definition was in memory
+            if ($def) {
+                if ($def->setup) {
+                    // invariant: $optimized === true (checked above)
+                    return null;
+                } else {
+                    return $def;
+                }
+            }
+            // if optimized, check if definition was in cache
+            // (because we do the memory check first, this formulation
+            // is prone to cache slamming, but I think
+            // guaranteeing that either /all/ of the raw
+            // setup code or /none/ of it is run is more important.)
+            if ($optimized) {
+                // This code path only gets run once; once we put
+                // something in $definitions (which is guaranteed by the
+                // trailing code), we always short-circuit above.
+                $def = $cache->get($this);
+                if ($def) {
+                    // save the full definition for later, but don't
+                    // return it yet
+                    $this->definitions[$type] = $def;
+                    return null;
+                }
+            }
+            // check invariants for creation
+            if (!$optimized) {
+                if (!is_null($this->get($type . '.DefinitionID'))) {
+                    if ($this->chatty) {
+                        $this->triggerError("Due to a documentation error in previous version of HTML Purifier, your definitions are not being cached.  If this is OK, you can remove the %$type.DefinitionRev and %$type.DefinitionID declaration.  Otherwise, modify your code to use maybeGetRawDefinition, and test if the returned value is null before making any edits (if it is null, that means that a cached version is available, and no raw operations are necessary).  See <a href='http://htmlpurifier.org/docs/enduser-customize.html#optimized'>Customize</a> for more details", E_USER_WARNING);
+                    } else {
+                        $this->triggerError("Useless DefinitionID declaration", E_USER_WARNING);
+                    }
+                }
+            }
+            // initialize it
+            $def = $this->initDefinition($type);
+            $def->optimized = $optimized;
+            return $def;
         }
+        throw new HTMLPurifier_Exception("The impossible happened!");
+    }
+
+    private function initDefinition($type) {
         // quick checks failed, let's create the object
         if ($type == 'HTML') {
-            $this->definitions[$type] = new HTMLPurifier_HTMLDefinition();
+            $def = new HTMLPurifier_HTMLDefinition();
         } elseif ($type == 'CSS') {
-            $this->definitions[$type] = new HTMLPurifier_CSSDefinition();
+            $def = new HTMLPurifier_CSSDefinition();
         } elseif ($type == 'URI') {
-            $this->definitions[$type] = new HTMLPurifier_URIDefinition();
+            $def = new HTMLPurifier_URIDefinition();
         } else {
             throw new HTMLPurifier_Exception("Definition of $type type not supported");
         }
-        // quick abort if raw
-        if ($raw) {
-            if (is_null($this->get($type, 'DefinitionID'))) {
-                // fatally error out if definition ID not set
-                throw new HTMLPurifier_Exception("Cannot retrieve raw version without specifying %$type.DefinitionID");
-            }
-            return $this->definitions[$type];
-        }
-        // set it up
-        $this->definitions[$type]->setup($this);
-        // save in cache
-        $cache->set($this->definitions[$type], $this);
-        return $this->definitions[$type];
+        $this->definitions[$type] = $def;
+        return $def;
+    }
+
+    public function maybeGetRawDefinition($name) {
+        return $this->getDefinition($name, true, true);
+    }
+
+    public function maybeGetRawHTMLDefinition() {
+        return $this->getDefinition('HTML', true, true);
+    }
+
+    public function maybeGetRawCSSDefinition() {
+        return $this->getDefinition('CSS', true, true);
+    }
+
+    public function maybeGetRawURIDefinition() {
+        return $this->getDefinition('URI', true, true);
     }
 
     /**
@@ -351,14 +528,12 @@ class HTMLPurifier_Config
         foreach ($config_array as $key => $value) {
             $key = str_replace('_', '.', $key);
             if (strpos($key, '.') !== false) {
-                // condensed form
-                list($namespace, $directive) = explode('.', $key);
-                $this->set($namespace, $directive, $value);
+                $this->set($key, $value);
             } else {
                 $namespace = $key;
                 $namespace_values = $value;
                 foreach ($namespace_values as $directive => $value) {
-                    $this->set($namespace, $directive, $value);
+                    $this->set($namespace .'.'. $directive, $value);
                 }
             }
         }
@@ -394,16 +569,15 @@ class HTMLPurifier_Config
              }
         }
         $ret = array();
-        foreach ($schema->info as $ns => $keypairs) {
-            foreach ($keypairs as $directive => $def) {
-                if ($allowed !== true) {
-                    if (isset($blacklisted_directives["$ns.$directive"])) continue;
-                    if (!isset($allowed_directives["$ns.$directive"]) && !isset($allowed_ns[$ns])) continue;
-                }
-                if (isset($def->isAlias)) continue;
-                if ($directive == 'DefinitionID' || $directive == 'DefinitionRev') continue;
-                $ret[] = array($ns, $directive);
+        foreach ($schema->info as $key => $def) {
+            list($ns, $directive) = explode('.', $key, 2);
+            if ($allowed !== true) {
+                if (isset($blacklisted_directives["$ns.$directive"])) continue;
+                if (!isset($allowed_directives["$ns.$directive"]) && !isset($allowed_ns[$ns])) continue;
             }
+            if (isset($def->isAlias)) continue;
+            if ($directive == 'DefinitionID' || $directive == 'DefinitionRev') continue;
+            $ret[] = array($ns, $directive);
         }
         return $ret;
     }
@@ -472,7 +646,7 @@ class HTMLPurifier_Config
      */
     public function isFinalized($error = false) {
         if ($this->finalized && $error) {
-            trigger_error($error, E_USER_ERROR);
+            $this->triggerError($error, E_USER_ERROR);
         }
         return $this->finalized;
     }
@@ -482,7 +656,11 @@ class HTMLPurifier_Config
      * already finalized
      */
     public function autoFinalize() {
-        if (!$this->finalized && $this->autoFinalize) $this->finalize();
+        if ($this->autoFinalize) {
+            $this->finalize();
+        } else {
+            $this->plist->squash(true);
+        }
     }
 
     /**
@@ -490,6 +668,40 @@ class HTMLPurifier_Config
      */
     public function finalize() {
         $this->finalized = true;
+        unset($this->parser);
+    }
+
+    /**
+     * Produces a nicely formatted error message by supplying the
+     * stack frame information OUTSIDE of HTMLPurifier_Config.
+     */
+    protected function triggerError($msg, $no) {
+        // determine previous stack frame
+        $extra = '';
+        if ($this->chatty) {
+            $trace = debug_backtrace();
+            // zip(tail(trace), trace) -- but PHP is not Haskell har har
+            for ($i = 0, $c = count($trace); $i < $c - 1; $i++) {
+                if ($trace[$i + 1]['class'] === 'HTMLPurifier_Config') {
+                    continue;
+                }
+                $frame = $trace[$i];
+                $extra = " invoked on line {$frame['line']} in file {$frame['file']}";
+                break;
+            }
+        }
+        trigger_error($msg . $extra, $no);
+    }
+
+    /**
+     * Returns a serialized form of the configuration object that can
+     * be reconstituted.
+     */
+    public function serialize() {
+        $this->getDefinition('HTML');
+        $this->getDefinition('CSS');
+        $this->getDefinition('URI');
+        return serialize($this);
     }
 
 }

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema.php

@@ -60,7 +60,13 @@ class HTMLPurifier_ConfigSchema {
      * Unserializes the default ConfigSchema.
      */
     public static function makeFromSerial() {
-        return unserialize(file_get_contents(HTMLPURIFIER_PREFIX . '/HTMLPurifier/ConfigSchema/schema.ser'));
+        $contents = file_get_contents(HTMLPURIFIER_PREFIX . '/HTMLPurifier/ConfigSchema/schema.ser');
+        $r = unserialize($contents);
+        if (!$r) {
+            $hash = sha1($contents);
+            trigger_error("Unserialization of configuration schema failed, sha1 of file was $hash", E_USER_ERROR);
+        }
+        return $r;
     }
 
     /**
@@ -87,24 +93,13 @@ class HTMLPurifier_ConfigSchema {
      *      HTMLPurifier_DirectiveDef::$type for allowed values
      * @param $allow_null Whether or not to allow null values
      */
-    public function add($namespace, $name, $default, $type, $allow_null) {
+    public function add($key, $default, $type, $allow_null) {
         $obj = new stdclass();
         $obj->type = is_int($type) ? $type : HTMLPurifier_VarParser::$types[$type];
         if ($allow_null) $obj->allow_null = true;
-        $this->info[$namespace][$name] = $obj;
-        $this->defaults[$namespace][$name] = $default;
-        $this->defaultPlist->set("$namespace.$name", $default);
-    }
-
-    /**
-     * Defines a namespace for directives to be put into.
-     * @warning This is slightly different from the corresponding static
-     *          method.
-     * @param $namespace Namespace's name
-     */
-    public function addNamespace($namespace) {
-        $this->info[$namespace] = array();
-        $this->defaults[$namespace] = array();
+        $this->info[$key] = $obj;
+        $this->defaults[$key] = $default;
+        $this->defaultPlist->set($key, $default);
     }
 
     /**
@@ -116,12 +111,12 @@ class HTMLPurifier_ConfigSchema {
      * @param $name Name of Directive
      * @param $aliases Hash of aliased values to the real alias
      */
-    public function addValueAliases($namespace, $name, $aliases) {
-        if (!isset($this->info[$namespace][$name]->aliases)) {
-            $this->info[$namespace][$name]->aliases = array();
+    public function addValueAliases($key, $aliases) {
+        if (!isset($this->info[$key]->aliases)) {
+            $this->info[$key]->aliases = array();
         }
         foreach ($aliases as $alias => $real) {
-            $this->info[$namespace][$name]->aliases[$alias] = $real;
+            $this->info[$key]->aliases[$alias] = $real;
         }
     }
 
@@ -133,8 +128,8 @@ class HTMLPurifier_ConfigSchema {
      * @param $name Name of directive
      * @param $allowed Lookup array of allowed values
      */
-    public function addAllowedValues($namespace, $name, $allowed) {
-        $this->info[$namespace][$name]->allowed = $allowed;
+    public function addAllowedValues($key, $allowed) {
+        $this->info[$key]->allowed = $allowed;
     }
 
     /**
@@ -144,88 +139,26 @@ class HTMLPurifier_ConfigSchema {
      * @param $new_namespace
      * @param $new_name Directive that the alias will be to
      */
-    public function addAlias($namespace, $name, $new_namespace, $new_name) {
+    public function addAlias($key, $new_key) {
         $obj = new stdclass;
-        $obj->namespace = $new_namespace;
-        $obj->name = $new_name;
+        $obj->key = $new_key;
         $obj->isAlias = true;
-        $this->info[$namespace][$name] = $obj;
+        $this->info[$key] = $obj;
     }
 
     /**
      * Replaces any stdclass that only has the type property with type integer.
      */
     public function postProcess() {
-        foreach ($this->info as $namespace => $info) {
-            foreach ($info as $directive => $v) {
-                if (count((array) $v) == 1) {
-                    $this->info[$namespace][$directive] = $v->type;
-                } elseif (count((array) $v) == 2 && isset($v->allow_null)) {
-                    $this->info[$namespace][$directive] = -$v->type;
-                }
+        foreach ($this->info as $key => $v) {
+            if (count((array) $v) == 1) {
+                $this->info[$key] = $v->type;
+            } elseif (count((array) $v) == 2 && isset($v->allow_null)) {
+                $this->info[$key] = -$v->type;
             }
         }
     }
 
-    // DEPRECATED METHODS
-
-    /** @see HTMLPurifier_ConfigSchema->set() */
-    public static function define($namespace, $name, $default, $type, $description) {
-        HTMLPurifier_ConfigSchema::deprecated(__METHOD__);
-        $type_values = explode('/', $type, 2);
-        $type = $type_values[0];
-        $modifier = isset($type_values[1]) ? $type_values[1] : false;
-        $allow_null = ($modifier === 'null');
-        $def = HTMLPurifier_ConfigSchema::instance();
-        $def->add($namespace, $name, $default, $type, $allow_null);
-    }
-
-    /** @see HTMLPurifier_ConfigSchema->addNamespace() */
-    public static function defineNamespace($namespace, $description) {
-        HTMLPurifier_ConfigSchema::deprecated(__METHOD__);
-        $def = HTMLPurifier_ConfigSchema::instance();
-        $def->addNamespace($namespace);
-    }
-
-    /** @see HTMLPurifier_ConfigSchema->addValueAliases() */
-    public static function defineValueAliases($namespace, $name, $aliases) {
-        HTMLPurifier_ConfigSchema::deprecated(__METHOD__);
-        $def = HTMLPurifier_ConfigSchema::instance();
-        $def->addValueAliases($namespace, $name, $aliases);
-    }
-
-    /** @see HTMLPurifier_ConfigSchema->addAllowedValues() */
-    public static function defineAllowedValues($namespace, $name, $allowed_values) {
-        HTMLPurifier_ConfigSchema::deprecated(__METHOD__);
-        $allowed = array();
-        foreach ($allowed_values as $value) {
-            $allowed[$value] = true;
-        }
-        $def = HTMLPurifier_ConfigSchema::instance();
-        $def->addAllowedValues($namespace, $name, $allowed);
-    }
-
-    /** @see HTMLPurifier_ConfigSchema->addAlias() */
-    public static function defineAlias($namespace, $name, $new_namespace, $new_name) {
-        HTMLPurifier_ConfigSchema::deprecated(__METHOD__);
-        $def = HTMLPurifier_ConfigSchema::instance();
-        $def->addAlias($namespace, $name, $new_namespace, $new_name);
-    }
-
-    /** @deprecated, use HTMLPurifier_VarParser->parse() */
-    public function validate($a, $b, $c = false) {
-        trigger_error("HTMLPurifier_ConfigSchema->validate deprecated, use HTMLPurifier_VarParser->parse instead", E_USER_NOTICE);
-        $parser = new HTMLPurifier_VarParser();
-        return $parser->parse($a, $b, $c);
-    }
-
-    /**
-     * Throws an E_USER_NOTICE stating that a method is deprecated.
-     */
-    private static function deprecated($method) {
-        trigger_error("Static HTMLPurifier_ConfigSchema::$method deprecated, use add*() method instead", E_USER_NOTICE);
-    }
-
 }
 
 // vim: et sw=4 sts=4

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/Builder/ConfigSchema.php

@@ -9,36 +9,28 @@ class HTMLPurifier_ConfigSchema_Builder_ConfigSchema
 
     public function build($interchange) {
         $schema = new HTMLPurifier_ConfigSchema();
-        foreach ($interchange->namespaces as $n) {
-            $schema->addNamespace($n->namespace);
-        }
         foreach ($interchange->directives as $d) {
             $schema->add(
-                $d->id->namespace,
-                $d->id->directive,
+                $d->id->key,
                 $d->default,
                 $d->type,
                 $d->typeAllowsNull
             );
             if ($d->allowed !== null) {
                 $schema->addAllowedValues(
-                    $d->id->namespace,
-                    $d->id->directive,
+                    $d->id->key,
                     $d->allowed
                 );
             }
             foreach ($d->aliases as $alias) {
                 $schema->addAlias(
-                    $alias->namespace,
-                    $alias->directive,
-                    $d->id->namespace,
-                    $d->id->directive
+                    $alias->key,
+                    $d->id->key
                 );
             }
             if ($d->valueAliases !== null) {
                 $schema->addValueAliases(
-                    $d->id->namespace,
-                    $d->id->directive,
+                    $d->id->key,
                     $d->valueAliases
                 );
             }

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/Builder/Xml.php

@@ -8,6 +8,7 @@ class HTMLPurifier_ConfigSchema_Builder_Xml extends XMLWriter
 {
 
     protected $interchange;
+    private $namespace;
 
     protected function writeHTMLDiv($html) {
         $this->startElement('div');
@@ -34,36 +35,33 @@ class HTMLPurifier_ConfigSchema_Builder_Xml extends XMLWriter
         $this->startElement('configdoc');
         $this->writeElement('title', $interchange->name);
 
-        foreach ($interchange->namespaces as $namespace) {
-            $this->buildNamespace($namespace);
+        foreach ($interchange->directives as $directive) {
+            $this->buildDirective($directive);
         }
 
+        if ($this->namespace) $this->endElement(); // namespace
+
         $this->endElement(); // configdoc
         $this->flush();
     }
 
-    public function buildNamespace($namespace) {
-        $this->startElement('namespace');
-        $this->writeAttribute('id', $namespace->namespace);
+    public function buildDirective($directive) {
 
-        $this->writeElement('name', $namespace->namespace);
-        $this->startElement('description');
-            $this->writeHTMLDiv($namespace->description);
-        $this->endElement(); // description
-
-        foreach ($this->interchange->directives as $directive) {
-            if ($directive->id->namespace !== $namespace->namespace) continue;
-            $this->buildDirective($directive);
+        // Kludge, although I suppose having a notion of a "root namespace"
+        // certainly makes things look nicer when documentation is built.
+        // Depends on things being sorted.
+        if (!$this->namespace || $this->namespace !== $directive->id->getRootNamespace()) {
+            if ($this->namespace) $this->endElement(); // namespace
+            $this->namespace = $directive->id->getRootNamespace();
+            $this->startElement('namespace');
+            $this->writeAttribute('id', $this->namespace);
+            $this->writeElement('name', $this->namespace);
         }
 
-        $this->endElement(); // namespace
-    }
-
-    public function buildDirective($directive) {
         $this->startElement('directive');
         $this->writeAttribute('id', $directive->id->toString());
 
-        $this->writeElement('name', $directive->id->directive);
+        $this->writeElement('name', $directive->id->getDirective());
 
         $this->startElement('aliases');
             foreach ($directive->aliases as $alias) $this->writeElement('alias', $alias->toString());

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/Interchange.php

@@ -13,26 +13,11 @@ class HTMLPurifier_ConfigSchema_Interchange
      */
     public $name;
 
-    /**
-     * Array of Namespace ID => array(namespace info)
-     */
-    public $namespaces = array();
-
     /**
      * Array of Directive ID => array(directive info)
      */
     public $directives = array();
 
-    /**
-     * Adds a namespace array to $namespaces
-     */
-    public function addNamespace($namespace) {
-        if (isset($this->namespaces[$i = $namespace->namespace])) {
-            throw new HTMLPurifier_ConfigSchema_Exception("Cannot redefine namespace '$i'");
-        }
-        $this->namespaces[$i] = $namespace;
-    }
-
     /**
      * Adds a directive array to $directives
      */

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/Interchange/Id.php

@@ -6,11 +6,10 @@
 class HTMLPurifier_ConfigSchema_Interchange_Id
 {
 
-    public $namespace, $directive;
+    public $key;
 
-    public function __construct($namespace, $directive) {
-        $this->namespace = $namespace;
-        $this->directive = $directive;
+    public function __construct($key) {
+        $this->key = $key;
     }
 
     /**
@@ -18,12 +17,19 @@ class HTMLPurifier_ConfigSchema_Interchange_Id
      *          cause problems for PHP 5.0 support.
      */
     public function toString() {
-        return $this->namespace . '.' . $this->directive;
+        return $this->key;
+    }
+
+    public function getRootNamespace() {
+        return substr($this->key, 0, strpos($this->key, "."));
+    }
+
+    public function getDirective() {
+        return substr($this->key, strpos($this->key, ".") + 1);
     }
 
     public static function make($id) {
-        list($namespace, $directive) = explode('.', $id);
-        return new HTMLPurifier_ConfigSchema_Interchange_Id($namespace, $directive);
+        return new HTMLPurifier_ConfigSchema_Interchange_Id($id);
     }
 
 }

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/InterchangeBuilder.php

@@ -13,13 +13,17 @@ class HTMLPurifier_ConfigSchema_InterchangeBuilder
     }
 
     public static function buildFromDirectory($dir = null) {
-        $parser      = new HTMLPurifier_StringHashParser();
         $builder     = new HTMLPurifier_ConfigSchema_InterchangeBuilder();
         $interchange = new HTMLPurifier_ConfigSchema_Interchange();
+        return $builder->buildDir($interchange, $dir);
+    }
 
-        if (!$dir) $dir = HTMLPURIFIER_PREFIX . '/HTMLPurifier/ConfigSchema/schema/';
-        $info = parse_ini_file($dir . 'info.ini');
-        $interchange->name = $info['name'];
+    public function buildDir($interchange, $dir = null) {
+        if (!$dir) $dir = HTMLPURIFIER_PREFIX . '/HTMLPurifier/ConfigSchema/schema';
+        if (file_exists($dir . '/info.ini')) {
+            $info = parse_ini_file($dir . '/info.ini');
+            $interchange->name = $info['name'];
+        }
 
         $files = array();
         $dh = opendir($dir);
@@ -33,15 +37,20 @@ class HTMLPurifier_ConfigSchema_InterchangeBuilder
 
         sort($files);
         foreach ($files as $file) {
-            $builder->build(
-                $interchange,
-                new HTMLPurifier_StringHash( $parser->parseFile($dir . $file) )
-            );
+            $this->buildFile($interchange, $dir . '/' . $file);
         }
 
         return $interchange;
     }
 
+    public function buildFile($interchange, $file) {
+        $parser = new HTMLPurifier_StringHashParser();
+        $this->build(
+            $interchange,
+            new HTMLPurifier_StringHash( $parser->parseFile($file) )
+        );
+    }
+
     /**
      * Builds an interchange object based on a hash.
      * @param $interchange HTMLPurifier_ConfigSchema_Interchange object to build
@@ -55,22 +64,17 @@ class HTMLPurifier_ConfigSchema_InterchangeBuilder
             throw new HTMLPurifier_ConfigSchema_Exception('Hash does not have any ID');
         }
         if (strpos($hash['ID'], '.') === false) {
-            $this->buildNamespace($interchange, $hash);
+            if (count($hash) == 2 && isset($hash['DESCRIPTION'])) {
+                $hash->offsetGet('DESCRIPTION'); // prevent complaining
+            } else {
+                throw new HTMLPurifier_ConfigSchema_Exception('All directives must have a namespace');
+            }
         } else {
             $this->buildDirective($interchange, $hash);
         }
         $this->_findUnused($hash);
     }
 
-    public function buildNamespace($interchange, $hash) {
-        $namespace = new HTMLPurifier_ConfigSchema_Interchange_Namespace();
-        $namespace->namespace   = $hash->offsetGet('ID');
-        if (isset($hash['DESCRIPTION'])) {
-            $namespace->description = $hash->offsetGet('DESCRIPTION');
-        }
-        $interchange->addNamespace($namespace);
-    }
-
     public function buildDirective($interchange, $hash) {
         $directive = new HTMLPurifier_ConfigSchema_Interchange_Directive();
 

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/Validator.php

@@ -39,10 +39,6 @@ class HTMLPurifier_ConfigSchema_Validator
         $this->aliases = array();
         // PHP is a bit lax with integer <=> string conversions in
         // arrays, so we don't use the identical !== comparison
-        foreach ($interchange->namespaces as $i => $namespace) {
-            if ($i != $namespace->namespace) $this->error(false, "Integrity violation: key '$i' does not match internal id '{$namespace->namespace}'");
-            $this->validateNamespace($namespace);
-        }
         foreach ($interchange->directives as $i => $directive) {
             $id = $directive->id->toString();
             if ($i != $id) $this->error(false, "Integrity violation: key '$i' does not match internal id '$id'");
@@ -51,20 +47,6 @@ class HTMLPurifier_ConfigSchema_Validator
         return true;
     }
 
-    /**
-     * Validates a HTMLPurifier_ConfigSchema_Interchange_Namespace object.
-     */
-    public function validateNamespace($n) {
-        $this->context[] = "namespace '{$n->namespace}'";
-        $this->with($n, 'namespace')
-            ->assertNotEmpty()
-            ->assertAlnum(); // implicit assertIsString handled by InterchangeBuilder
-        $this->with($n, 'description')
-            ->assertNotEmpty()
-            ->assertIsString(); // handled by InterchangeBuilder
-        array_pop($this->context);
-    }
-
     /**
      * Validates a HTMLPurifier_ConfigSchema_Interchange_Id object.
      */
@@ -75,12 +57,11 @@ class HTMLPurifier_ConfigSchema_Validator
             // handled by InterchangeBuilder
             $this->error(false, 'is not an instance of HTMLPurifier_ConfigSchema_Interchange_Id');
         }
-        if (!isset($this->interchange->namespaces[$id->namespace])) {
-            $this->error('namespace', 'does not exist'); // assumes that the namespace was validated already
-        }
-        $this->with($id, 'directive')
+        // keys are now unconstrained (we might want to narrow down to A-Za-z0-9.)
+        // we probably should check that it has at least one namespace
+        $this->with($id, 'key')
             ->assertNotEmpty()
-            ->assertAlnum(); // implicit assertIsString handled by InterchangeBuilder
+            ->assertIsString(); // implicit assertIsString handled by InterchangeBuilder
         array_pop($this->context);
     }
 

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/schema/Attr.AllowedClasses.txt

@@ -0,0 +1,8 @@
+Attr.AllowedClasses
+TYPE: lookup/null
+VERSION: 4.0.0
+DEFAULT: null
+--DESCRIPTION--
+List of allowed class values in the class attribute. By default, this is null,
+which means all classes are allowed.
+--# vim: et sw=4 sts=4

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/schema/Attr.ClassUseCDATA.txt

@@ -0,0 +1,19 @@
+Attr.ClassUseCDATA
+TYPE: bool/null
+DEFAULT: null
+VERSION: 4.0.0
+--DESCRIPTION--
+If null, class will auto-detect the doctype and, if matching XHTML 1.1 or
+XHTML 2.0, will use the restrictive NMTOKENS specification of class. Otherwise,
+it will use a relaxed CDATA definition.  If true, the relaxed CDATA definition
+is forced; if false, the NMTOKENS definition is forced.  To get behavior
+of HTML Purifier prior to 4.0.0, set this directive to false.
+
+Some rational behind the auto-detection:
+in previous versions of HTML Purifier, it was assumed that the form of
+class was NMTOKENS, as specified by the XHTML Modularization (representing
+XHTML 1.1 and XHTML 2.0).  The DTDs for HTML 4.01 and XHTML 1.0, however
+specify class as CDATA.  HTML 5 effectively defines it as CDATA, but
+with the additional constraint that each name should be unique (this is not
+explicitly outlined in previous specifications).
+--# vim: et sw=4 sts=4

lib/htmlpurifier/library/HTMLPurifier/ConfigSchema/schema/Attr.ForbiddenClasses.txt

@@ -0,0 +1,8 @@
+Attr.ForbiddenClasses
+TYPE: lookup
+VERSION: 4.0.0
+DEFAULT: array()
+--DESCRIPTION--
+List of forbidden class values in the class attribute. By default, this is
+empty, which means that no classes are forbidden. See also %Attr.AllowedClasses.
+--# vim: et sw=4 sts=4