services/network/public/mojom/network_interface_change_listener.mojom

// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module network.mojom;

import "services/network/public/mojom/ip_address.mojom";

// The corresponds to a struct ifaddrmsg sent from the Linux kernel, see
// https://man7.org/linux/man-pages/man7/rtnetlink.7.html.
// Note that there is no way to validate any of these values, and so this should
// normally only be sent from a trusted process.
[EnableIf=use_network_interface_change_listener]
struct IfAddrMsg {
  uint8 ifa_family;
  uint8 ifa_prefixlen;
  uint8 ifa_flags;
  uint8 ifa_scope;
  uint32 ifa_index;
};

// The counterpart to AddressMapOwnerLinux::AddressMap.
[EnableIf=use_network_interface_change_listener]
struct AddressMap {
  // Mapped to an AddressMap.
  map<network.mojom.IPAddress, IfAddrMsg> address_map;
};

// The counterpart to the std::unordered_set<int> of online links maintained in
// AddressMapOwnerLinux.
[EnableIf=use_network_interface_change_listener]
struct OnlineLinks {
  // Mapped to an std::unordered_set<int>.
  array<int32> online_links;
};

// This data is necessary to initialize AddressMapCacheLinux, for example in the
// sandboxed network service where AddressTrackerLinux can't be used instead.
[EnableIf=use_network_interface_change_listener]
struct InitialAddressMap {
  // The initial AddressMap.
  AddressMap address_map;
  // The initial online interfaces.
  OnlineLinks online_links;
};

// Represents a diff of an AddressMap and a set of online links.
[EnableIf=use_network_interface_change_listener]
struct NetworkInterfaceChangeParams {
  // Maps an IPAddress to null if the IPAddress has been removed from the map.
  // Otherwise maps an IPAddress to an IfAddrMsg if the entry has been changed
  // or added.
  map<network.mojom.IPAddress, IfAddrMsg?> address_map;
  // Maps an interface index to true if it has been added to the set, and false
  // if it has been removed from the set.
  map<int32, bool> online_links;
};

// Used to listen for changes to the network interfaces (e.g. updates received
// via netlink from the Linux kernel).
[EnableIf=use_network_interface_change_listener]
interface NetworkInterfaceChangeListener {
  // Called when there is a change to the network interfaces.
  OnNetworkInterfacesChanged(NetworkInterfaceChangeParams params);
};