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-rw-r--r--library/HTMLPurifier/URIScheme/data.php93
1 files changed, 93 insertions, 0 deletions
diff --git a/library/HTMLPurifier/URIScheme/data.php b/library/HTMLPurifier/URIScheme/data.php
new file mode 100644
index 000000000..b7f1989cb
--- /dev/null
+++ b/library/HTMLPurifier/URIScheme/data.php
@@ -0,0 +1,93 @@
+<?php
+
+/**
+ * Implements data: URI for base64 encoded images supported by GD.
+ */
+class HTMLPurifier_URIScheme_data extends HTMLPurifier_URIScheme {
+
+ public $browsable = true;
+ public $allowed_types = array(
+ // you better write validation code for other types if you
+ // decide to allow them
+ 'image/jpeg' => true,
+ 'image/gif' => true,
+ 'image/png' => true,
+ );
+
+ public function validate(&$uri, $config, $context) {
+ $result = explode(',', $uri->path, 2);
+ $is_base64 = false;
+ $charset = null;
+ $content_type = null;
+ if (count($result) == 2) {
+ list($metadata, $data) = $result;
+ // do some legwork on the metadata
+ $metas = explode(';', $metadata);
+ while(!empty($metas)) {
+ $cur = array_shift($metas);
+ if ($cur == 'base64') {
+ $is_base64 = true;
+ break;
+ }
+ if (substr($cur, 0, 8) == 'charset=') {
+ // doesn't match if there are arbitrary spaces, but
+ // whatever dude
+ if ($charset !== null) continue; // garbage
+ $charset = substr($cur, 8); // not used
+ } else {
+ if ($content_type !== null) continue; // garbage
+ $content_type = $cur;
+ }
+ }
+ } else {
+ $data = $result[0];
+ }
+ if ($content_type !== null && empty($this->allowed_types[$content_type])) {
+ return false;
+ }
+ if ($charset !== null) {
+ // error; we don't allow plaintext stuff
+ $charset = null;
+ }
+ $data = rawurldecode($data);
+ if ($is_base64) {
+ $raw_data = base64_decode($data);
+ } else {
+ $raw_data = $data;
+ }
+ // XXX probably want to refactor this into a general mechanism
+ // for filtering arbitrary content types
+ $file = tempnam("/tmp", "");
+ file_put_contents($file, $raw_data);
+ if (function_exists('exif_imagetype')) {
+ $image_code = exif_imagetype($file);
+ } elseif (function_exists('getimagesize')) {
+ set_error_handler(array($this, 'muteErrorHandler'));
+ $info = getimagesize($file);
+ restore_error_handler();
+ if ($info == false) return false;
+ $image_code = $info[2];
+ } else {
+ trigger_error("could not find exif_imagetype or getimagesize functions", E_USER_ERROR);
+ }
+ $real_content_type = image_type_to_mime_type($image_code);
+ if ($real_content_type != $content_type) {
+ // we're nice guys; if the content type is something else we
+ // support, change it over
+ if (empty($this->allowed_types[$real_content_type])) return false;
+ $content_type = $real_content_type;
+ }
+ // ok, it's kosher, rewrite what we need
+ $uri->userinfo = null;
+ $uri->host = null;
+ $uri->port = null;
+ $uri->fragment = null;
+ $uri->query = null;
+ $uri->path = "$content_type;base64," . base64_encode($raw_data);
+ return true;
+ }
+
+ public function muteErrorHandler($errno, $errstr) {}
+
+}
+