NQE: Exclude network observations from private networks

net/nqe/network_quality_estimator_util.cc

Index: net/nqe/network_quality_estimator_util.cc
diff --git a/net/nqe/network_quality_estimator_util.cc b/net/nqe/network_quality_estimator_util.cc
new file mode 100644
index 0000000000000000000000000000000000000000..cdc64858ba241d2bbd8b99858d9a7f2f0e8ea556
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+++ b/net/nqe/network_quality_estimator_util.cc
@@ -0,0 +1,59 @@
+// Copyright 2017 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 "net/nqe/network_quality_estimator_util.h"
+
+#include "net/base/address_list.h"
+#include "net/base/host_port_pair.h"
+#include "net/base/ip_address.h"
+#include "net/base/ip_endpoint.h"
+#include "net/base/net_errors.h"
+#include "net/base/url_util.h"
+#include "net/dns/host_resolver.h"
+
+namespace net {
+
+namespace nqe {
+
+namespace internal {
+
+bool IsPrivateHost(HostResolver* host_resolver,
+                   const HostPortPair& host_port_pair,
+                   const NetLogWithSource& net_log) {
+  if (IsLocalhost(host_port_pair.host()))

[mmenke, 2017/06/16 15:03:58]

Again, not needed if host_resolver is non-null, per below comment.

[tbansal1, 2017/06/17 01:54:00]

Done.

+    return true;
+
+  // Check if |host_port_pair.host()| is a reserved IP address.
+  net::IPAddress ip_address;
+  if (ip_address.AssignFromIPLiteral(host_port_pair.host()) &&
+      ip_address.IsReserved()) {

[mmenke, 2017/06/16 15:03:58]

If host_resolver is guaranteed to be non-NULL, this check isn't needed, since
host_resolver will handle IP literals.

Otherwise, if AssignFromIPLiteral is true, and IsReserved is false, could
optionally just return false here.  Shouldn't really matter much.

[tbansal1, 2017/06/17 01:54:00]

Done.

+    return true;
+  }
+
+  if (host_resolver) {

[mmenke, 2017/06/16 15:03:58]

If you decide to keep this optional (I recommend against that, unless it's
really needed), should have a test with an empty host_resolver that reaches the
final "return false;"

[tbansal1, 2017/06/17 01:54:00]

Done.

+    // Try resolving |host_port_pair.host()| synchronously.
+    HostResolver::RequestInfo resolve_info(host_port_pair);
+    resolve_info.set_allow_cached_response(true);
+    AddressList addresses;
+    // Resolve synchronously using the resolver's cache.
+    int rv = host_resolver->ResolveFromCache(resolve_info, &addresses, net_log);
+
+    DCHECK_NE(rv, ERR_IO_PENDING);
+    if (rv == OK && !addresses.empty()) {
+      // Checking only the first address should be sufficient.
+      IPEndPoint ip_end_point = addresses.front();
+      ip_address = ip_end_point.address();
+      if (ip_address.IsReserved()) {
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+}  // namespace internal
+
+}  // namespace nqe
+
+}  // namespace net