Make net::DataURL's MIME string check stricter

net/base/data_url.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // NOTE: based loosely on mozilla's nsDataChannel.cpp
 
 #include <algorithm>
 
 #include "net/base/data_url.h"
 
 #include "base/base64.h"
 #include "base/basictypes.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "net/base/escape.h"
+#include "net/base/mime_util.h"
 #include "url/gurl.h"
 
 namespace net {
 
 // static
 bool DataURL::Parse(const GURL& url, std::string* mime_type,
                     std::string* charset, std::string* data) {
   DCHECK(mime_type->empty());
   DCHECK(charset->empty());
   std::string::const_iterator begin = url.spec().begin();
@@ skipping 26 matching lines @@
   bool base64_encoded = false;
   for (; iter != meta_data.end(); ++iter) {
     if (!base64_encoded && *iter == kBase64Tag) {
       base64_encoded = true;
     } else if (charset->empty() &&
                iter->compare(0, kCharsetTagLength, kCharsetTag) == 0) {
       charset->assign(iter->substr(kCharsetTagLength));
     }
   }
 
-  // fallback to defaults if nothing specified in the URL:
-  if (mime_type->empty())
+  if (mime_type->empty()) {
+    // fallback to defaults if nothing specified in the URL:
     mime_type->assign("text/plain");
+  } else if (!ParseMimeTypeWithoutParameter(*mime_type, NULL, NULL)) {
+    return false;
+  }
   if (charset->empty())
     charset->assign("US-ASCII");
 
   // The caller may not be interested in receiving the data.
   if (!data)
     return true;
 
   // Preserve spaces if dealing with text or xml input, same as mozilla:
   //   https://bugzilla.mozilla.org/show_bug.cgi?id=138052
   // but strip them otherwise:
@@ skipping 39 matching lines @@
       temp_data.resize(length + padding_needed, '=');
     }
     return base::Base64Decode(temp_data, data);
   }
 
   temp_data.swap(*data);
   return true;
 }
 
 }  // namespace net