Curtain mode implementation for Mac OS X.

remoting/host/curtain_mode_mac.cc

Index: remoting/host/curtain_mode_mac.cc
diff --git a/remoting/host/curtain_mode_mac.cc b/remoting/host/curtain_mode_mac.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b2ffcea8f08d2a684b0bb300e43d84ea38b39f3d
--- /dev/null
+++ b/remoting/host/curtain_mode_mac.cc
@@ -0,0 +1,76 @@
+// 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.
+
+#include "remoting/host/curtain_mode_mac.h"
+
+#include <ApplicationServices/ApplicationServices.h>
+#include <Security/Security.h>
+
+#include "base/logging.h"
+#include "base/mac/scoped_cftyperef.h"
+
+namespace {
+static const char* kCGSessionPath =

[Lambros, 2012/08/08 00:48:29]

nit: don't need static in anon namespace

[Jamie, 2012/08/08 01:39:43]

Done.

+    "/System/Library/CoreServices/Menu Extras/User.menu/Contents/Resources/"
+    "CGSession";
+}
+
+namespace remoting {
+
+CurtainMode::CurtainMode() : event_handler_(NULL) {
+}
+
+CurtainMode::~CurtainMode() {
+  if (event_handler_) {
+    RemoveEventHandler(event_handler_);
+  }
+}
+
+bool CurtainMode::Init(const base::Closure& on_session_activate) {
+  DCHECK(on_session_activate_.is_null());
+  on_session_activate_ = on_session_activate;
+  EventTypeSpec event;
+  event.eventClass = kEventClassSystem;
+  event.eventKind = kEventSystemUserSessionActivated;
+  OSStatus result = InstallApplicationEventHandler(
+      NewEventHandlerUPP(SessionActivateHandler), 1, &event, this,
+      &event_handler_);
+  return result == noErr;
+}
+
+void CurtainMode::OnClientAuthenticated(const std::string& jid) {
+  // If the current session is attached to the console and is not showing
+  // the logon screen then switch it out to ensure privacy.
+  base::mac::ScopedCFTypeRef<CFDictionaryRef> session(
+      CGSessionCopyCurrentDictionary());
+  const void* on_console = CFDictionaryGetValue(session,
+                                                kCGSessionOnConsoleKey);
+  const void* logged_in = CFDictionaryGetValue(session, kCGSessionLoginDoneKey);
+  if (logged_in == kCFBooleanTrue && on_console == kCFBooleanTrue) {
+    pid_t child = fork();
+    if (child == 0) {
+      execl(kCGSessionPath, kCGSessionPath, "-suspend", NULL);

[Lambros, 2012/08/08 00:48:29]

Is there a C API equivalent of this command-line tool?
Do we care about logging errors if fork/exec fails?
Will this still work if Fast User Switching is not enabled?

[Jamie, 2012/08/08 01:39:43]

I couldn't find one last time I looked, but I agree that it would be a lot nicer
if such an API existed.
That's a good point. I think for now we don't care, but once I add in policy
support, we'll want to close the connection if it can't be curtained.
Another good point. I don't know how to turn off FUS to test it. Removing the
menu doesn't prevent it from working.

+      exit(1);

[Lambros, 2012/08/08 00:48:29]

Use _exit instead of exit (after a fork with failed exec).

[Jamie, 2012/08/08 01:39:43]

Done.

+    } else if (child > 0) {
+      int status = 0;
+      waitpid(child, &status, 0);
+    }
+  }
+}
+
+OSStatus CurtainMode::SessionActivateHandler(EventHandlerCallRef handler,
+                                             EventRef event,
+                                             void* user_data) {
+  CurtainMode* self = reinterpret_cast<CurtainMode*>(user_data);

[Lambros, 2012/08/08 00:48:29]

nit: Use static_cast<> ?

[Jamie, 2012/08/08 01:39:43]

Done.

+  self->OnSessionActivate();
+  return noErr;
+}
+
+void CurtainMode::OnSessionActivate() {
+  if (!on_session_activate_.is_null()) {
+    on_session_activate_.Run();
+  }
+}
+
+}

[Lambros, 2012/08/08 00:48:29]

nit: // namespace remoting

[Jamie, 2012/08/08 01:39:43]

Done.