strip_tags_long: use htmlpurifier to properly reformat html content

1 files changed, 90 insertions, 0 deletions

diff --git a/lib/htmlpurifier/library/HTMLPurifier/AttrDef/CSS/FontFamily.php b/lib/htmlpurifier/library/HTMLPurifier/AttrDef/CSS/FontFamily.php
new file mode 100755
index 000000000..705ac893d
--- /dev/null
+++ b/lib/htmlpurifier/library/HTMLPurifier/AttrDef/CSS/FontFamily.php
@@ -0,0 +1,90 @@
+<?php
+
+/**
+ * Validates a font family list according to CSS spec
+ * @todo whitelisting allowed fonts would be nice
+ */
+class HTMLPurifier_AttrDef_CSS_FontFamily extends HTMLPurifier_AttrDef
+{
+
+    public function validate($string, $config, $context) {
+        static $generic_names = array(
+            'serif' => true,
+            'sans-serif' => true,
+            'monospace' => true,
+            'fantasy' => true,
+            'cursive' => true
+        );
+
+        // assume that no font names contain commas in them
+        $fonts = explode(',', $string);
+        $final = '';
+        foreach($fonts as $font) {
+            $font = trim($font);
+            if ($font === '') continue;
+            // match a generic name
+            if (isset($generic_names[$font])) {
+                $final .= $font . ', ';
+                continue;
+            }
+            // match a quoted name
+            if ($font[0] === '"' || $font[0] === "'") {
+                $length = strlen($font);
+                if ($length <= 2) continue;
+                $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;
+            }
+            // $font is a pure representation of the font name
+
+            if (ctype_alnum($font) && $font !== '') {
+                // very simple font, allow it in unharmed
+                $final .= $font . ', ';
+                continue;
+            }
+
+            // complicated font, requires quoting
+
+            // armor single quotes and new lines
+            $font = str_replace("\\", "\\\\", $font);
+            $font = str_replace("'", "\\'", $font);
+            $final .= "'$font', ";
+        }
+        $final = rtrim($final, ', ');
+        if ($final === '') return false;
+        return $final;
+    }
+
+}
+
+// vim: et sw=4 sts=4