Remote Assistance on Chrome OS Part III - NativeMessageHost

extensions/browser/api/messaging/native_message_host.cc

Index: extensions/browser/api/messaging/native_message_host.cc
diff --git a/extensions/browser/api/messaging/native_message_host.cc b/extensions/browser/api/messaging/native_message_host.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8abc399f2397c436870f2839a2097c6b896f3955
--- /dev/null
+++ b/extensions/browser/api/messaging/native_message_host.cc
@@ -0,0 +1,52 @@
+// Copyright 2014 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 "extensions/browser/api/messaging/native_message_host.h"
+
+#include "base/prefs/pref_service.h"
+#include "base/values.h"
+#include "extensions/browser/pref_names.h"
+
+namespace extensions {
+
+// static
+NativeMessageHost::PolicyPermission
+NativeMessageHost::IsHostAllowed(const PrefService* pref_service,

[Sergey Ulanov, 2014/09/22 23:42:59]

I don't think this function belongs in this interface. Maybe move it in
message_service.cc? 

[kelvinp, 2014/09/23 20:16:42]

Done.

+                                        const std::string& native_host_name) {
+  NativeMessageHost::PolicyPermission allow_result = ALLOW_ALL;
+  if (pref_service->IsManagedPreference(
+          pref_names::kNativeMessagingUserLevelHosts)) {
+    if (!pref_service->GetBoolean(pref_names::kNativeMessagingUserLevelHosts))
+      allow_result = ALLOW_SYSTEM_ONLY;
+  }
+
+  // All native messaging hosts are allowed if there is no blacklist.
+  if (!pref_service->IsManagedPreference(pref_names::kNativeMessagingBlacklist))
+    return allow_result;
+  const base::ListValue* blacklist =
+      pref_service->GetList(pref_names::kNativeMessagingBlacklist);
+  if (!blacklist)
+    return allow_result;
+
+  // Check if the name or the wildcard is in the blacklist.
+  base::StringValue name_value(native_host_name);
+  base::StringValue wildcard_value("*");
+  if (blacklist->Find(name_value) == blacklist->end() &&
+      blacklist->Find(wildcard_value) == blacklist->end()) {
+    return allow_result;
+  }
+
+  // The native messaging host is blacklisted. Check the whitelist.
+  if (pref_service->IsManagedPreference(
+          pref_names::kNativeMessagingWhitelist)) {
+    const base::ListValue* whitelist =
+        pref_service->GetList(pref_names::kNativeMessagingWhitelist);
+    if (whitelist && whitelist->Find(name_value) != whitelist->end())
+      return allow_result;
+  }
+
+  return DISALLOW;
+}
+
+}  // namespace extensions