Enable websocket filtering via SubresourceFilter

third_party/WebKit/Source/modules/websockets/DocumentWebSocketChannel.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 15 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "modules/websockets/DocumentWebSocketChannel.h"
 
 #include <memory>
 #include "core/dom/DOMArrayBuffer.h"
 #include "core/dom/ExecutionContext.h"
+#include "core/dom/TaskRunnerHelper.h"
 #include "core/fileapi/FileReaderLoader.h"
 #include "core/fileapi/FileReaderLoaderClient.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/LocalFrameClient.h"
 #include "core/inspector/ConsoleMessage.h"
 #include "core/inspector/InspectorInstrumentation.h"
+#include "core/loader/DocumentLoader.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/MixedContentChecker.h"
+#include "core/loader/SubresourceFilter.h"
 #include "core/loader/ThreadableLoadingContext.h"
 #include "modules/websockets/InspectorWebSocketEvents.h"
 #include "modules/websockets/WebSocketChannelClient.h"
 #include "modules/websockets/WebSocketFrame.h"
 #include "modules/websockets/WebSocketHandleImpl.h"
 #include "platform/WebFrameScheduler.h"
 #include "platform/loader/fetch/UniqueIdentifier.h"
 #include "platform/network/NetworkLog.h"
 #include "platform/network/WebSocketHandshakeRequest.h"
 #include "platform/weborigin/SecurityOrigin.h"
@@ skipping 123 matching lines @@
   m_url = url;
   Vector<String> protocols;
   // Avoid placing an empty token in the Vector when the protocol string is
   // empty.
   if (!protocol.isEmpty()) {
     // Since protocol is already verified and escaped, we can simply split
     // it.
     protocol.split(", ", true, protocols);
   }
 
+  // If the connection needs to be filtered, asynchronously fail. Synchronous
+  // failure blocks the worker thread which should be avoided. Note that
+  // returning "true" just indicates that this was not a mixed content error.
+  if (shouldDisallowConnection(url)) {
+    TaskRunnerHelper::get(TaskType::Networking, document())

[engedy, 2017/03/06 16:31:01]

nit: For this, do we need include a subset of {WebTaskRunner.h,
WebTraceLocation.h, Functional.h}?

[Charlie Harrison, 2017/03/06 19:22:12]

Done.

+        ->postTask(
+            BLINK_FROM_HERE,
+            WTF::bind(
+                &DocumentWebSocketChannel::fail, wrapPersistent(this),
+                String("Connection disallowed by the subresource filter"),

[engedy, 2017/03/06 16:31:01]

Phrasing nit: WDYT about "... by subresource filtering rules"?

[engedy, 2017/03/06 17:46:13]

On second thought, let's hold off on printing the console message until we have
the final strings here.

[Charlie Harrison, 2017/03/06 19:22:12]

Done.

+                WarningMessageLevel,

[engedy, 2017/03/06 16:31:01]

Do we print anything else to the console other than this?  I wonder if this
should be a warning or error to be consistent with other failure modes.

[Charlie Harrison, 2017/03/06 19:22:12]

It does make more sense as an error level since we don't even initiate the
connection. I've changed it.

+                WTF::passed(SourceLocation::create(String(), 0, 0, nullptr))));
+    return true;
+  }
+
   // TODO(kinuko): document() should return nullptr if we don't
   // have valid document/frame that returns non-empty interface provider.
   if (document() && document()->frame() &&
       document()->frame()->interfaceProvider() !=
           InterfaceProvider::getEmptyInterfaceProvider()) {
     // Initialize the WebSocketHandle with the frame's InterfaceProvider to
     // provide the WebSocket implementation with context about this frame.
     // This is important so that the browser can show UI associated with
     // the WebSocket (e.g., for certificate errors).
     m_handle->initialize(document()->frame()->interfaceProvider());
@@ skipping 477 matching lines @@
   m_blobLoader.clear();
   if (errorCode == FileError::kAbortErr) {
     // The error is caused by cancel().
     return;
   }
   // FIXME: Generate human-friendly reason message.
   failAsError("Failed to load Blob: error code = " + String::number(errorCode));
   // |this| can be deleted here.
 }
 
+bool DocumentWebSocketChannel::shouldDisallowConnection(const KURL& url) {
+  DCHECK(m_handle);
+  DocumentLoader* loader = document()->loader();
+  if (!loader)
+    return false;
+  SubresourceFilter* subresourceFilter = loader->subresourceFilter();
+  if (!subresourceFilter)
+    return false;
+  return !subresourceFilter->allowWebSocketConnection(url);
+}
+
 DEFINE_TRACE(DocumentWebSocketChannel) {
   visitor->trace(m_blobLoader);
   visitor->trace(m_messages);
   visitor->trace(m_client);
   visitor->trace(m_loadingContext);
   WebSocketChannel::trace(visitor);
 }
 
 std::ostream& operator<<(std::ostream& ostream,
                          const DocumentWebSocketChannel* channel) {
   return ostream << "DocumentWebSocketChannel "
                  << static_cast<const void*>(channel);
 }
 
 }  // namespace blink