/* * Copyright (C) 2020 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.android.net.module.util; import android.net.InetAddresses; import java.net.Inet4Address; import java.net.Inet6Address; import java.net.InetAddress; import java.net.UnknownHostException; /** * Network constants used by the network stack. * @hide */ public final class NetworkStackConstants { /** * Ethernet constants. * * See also: * - https://tools.ietf.org/html/rfc894 * - https://tools.ietf.org/html/rfc2464 * - https://tools.ietf.org/html/rfc7042 * - http://www.iana.org/assignments/ethernet-numbers/ethernet-numbers.xhtml * - http://www.iana.org/assignments/ieee-802-numbers/ieee-802-numbers.xhtml */ public static final int ETHER_DST_ADDR_OFFSET = 0; public static final int ETHER_SRC_ADDR_OFFSET = 6; public static final int ETHER_ADDR_LEN = 6; public static final int ETHER_TYPE_OFFSET = 12; public static final int ETHER_TYPE_LENGTH = 2; public static final int ETHER_TYPE_ARP = 0x0806; public static final int ETHER_TYPE_IPV4 = 0x0800; public static final int ETHER_TYPE_IPV6 = 0x86dd; public static final int ETHER_HEADER_LEN = 14; public static final int ETHER_MTU = 1500; public static final byte[] ETHER_BROADCAST = new byte[] { (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff, }; /** * ARP constants. * * See also: * - https://tools.ietf.org/html/rfc826 * - http://www.iana.org/assignments/arp-parameters/arp-parameters.xhtml */ public static final int ARP_PAYLOAD_LEN = 28; // For Ethernet+IPv4. public static final int ARP_ETHER_IPV4_LEN = ARP_PAYLOAD_LEN + ETHER_HEADER_LEN; public static final int ARP_REQUEST = 1; public static final int ARP_REPLY = 2; public static final int ARP_HWTYPE_RESERVED_LO = 0; public static final int ARP_HWTYPE_ETHER = 1; public static final int ARP_HWTYPE_RESERVED_HI = 0xffff; /** * IPv4 Address Conflict Detection constants. * * See also: * - https://tools.ietf.org/html/rfc5227 */ public static final int IPV4_CONFLICT_PROBE_NUM = 3; public static final int IPV4_CONFLICT_ANNOUNCE_NUM = 2; /** * IPv4 constants. * * See also: * - https://tools.ietf.org/html/rfc791 */ public static final int IPV4_ADDR_BITS = 32; public static final int IPV4_MIN_MTU = 68; public static final int IPV4_MAX_MTU = 65_535; public static final int IPV4_HEADER_MIN_LEN = 20; public static final int IPV4_IHL_MASK = 0xf; public static final int IPV4_FLAGS_OFFSET = 6; public static final int IPV4_FRAGMENT_MASK = 0x1fff; public static final int IPV4_PROTOCOL_OFFSET = 9; public static final int IPV4_SRC_ADDR_OFFSET = 12; public static final int IPV4_DST_ADDR_OFFSET = 16; public static final int IPV4_ADDR_LEN = 4; public static final Inet4Address IPV4_ADDR_ALL = makeInet4Address( (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff); public static final Inet4Address IPV4_ADDR_ANY = makeInet4Address( (byte) 0, (byte) 0, (byte) 0, (byte) 0); public static final Inet6Address IPV6_ADDR_ANY = makeInet6Address(new byte[]{ (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0 }); /** * IPv6 constants. * * See also: * - https://tools.ietf.org/html/rfc2460 */ public static final int IPV6_ADDR_LEN = 16; public static final int IPV6_HEADER_LEN = 40; public static final int IPV6_LEN_OFFSET = 4; public static final int IPV6_PROTOCOL_OFFSET = 6; public static final int IPV6_SRC_ADDR_OFFSET = 8; public static final int IPV6_DST_ADDR_OFFSET = 24; public static final int IPV6_MIN_MTU = 1280; public static final Inet6Address IPV6_ADDR_ALL_NODES_MULTICAST = (Inet6Address) InetAddresses.parseNumericAddress("ff02::1"); public static final Inet6Address IPV6_ADDR_ALL_ROUTERS_MULTICAST = (Inet6Address) InetAddresses.parseNumericAddress("ff02::2"); public static final Inet6Address IPV6_ADDR_ALL_HOSTS_MULTICAST = (Inet6Address) InetAddresses.parseNumericAddress("ff02::3"); /** * ICMPv6 constants. * * See also: * - https://tools.ietf.org/html/rfc4443 * - https://tools.ietf.org/html/rfc4861 */ public static final int ICMPV6_HEADER_MIN_LEN = 4; public static final int ICMPV6_CHECKSUM_OFFSET = 2; public static final int ICMPV6_ECHO_REPLY_TYPE = 129; public static final int ICMPV6_ECHO_REQUEST_TYPE = 128; public static final int ICMPV6_ROUTER_SOLICITATION = 133; public static final int ICMPV6_ROUTER_ADVERTISEMENT = 134; public static final int ICMPV6_NEIGHBOR_SOLICITATION = 135; public static final int ICMPV6_NEIGHBOR_ADVERTISEMENT = 136; public static final int ICMPV6_ND_OPTION_MIN_LENGTH = 8; public static final int ICMPV6_ND_OPTION_LENGTH_SCALING_FACTOR = 8; public static final int ICMPV6_ND_OPTION_SLLA = 1; public static final int ICMPV6_ND_OPTION_TLLA = 2; public static final int ICMPV6_ND_OPTION_PIO = 3; public static final int ICMPV6_ND_OPTION_MTU = 5; public static final int ICMPV6_ND_OPTION_RDNSS = 25; public static final int ICMPV6_ND_OPTION_PREF64 = 38; public static final int ICMPV6_RA_HEADER_LEN = 16; public static final int NEIGHBOR_ADVERTISEMENT_FLAG_ROUTER = 1 << 31; public static final int NEIGHBOR_ADVERTISEMENT_FLAG_SOLICITED = 1 << 30; public static final int NEIGHBOR_ADVERTISEMENT_FLAG_OVERRIDE = 1 << 29; public static final byte ROUTER_ADVERTISEMENT_FLAG_MANAGED_ADDRESS = (byte) (1 << 7); public static final byte ROUTER_ADVERTISEMENT_FLAG_OTHER = (byte) (1 << 6); public static final byte PIO_FLAG_ON_LINK = (byte) (1 << 7); public static final byte PIO_FLAG_AUTONOMOUS = (byte) (1 << 6); /** * UDP constants. * * See also: * - https://tools.ietf.org/html/rfc768 */ public static final int UDP_HEADER_LEN = 8; /** * DHCP constants. * * See also: * - https://tools.ietf.org/html/rfc2131 */ public static final int INFINITE_LEASE = 0xffffffff; public static final int DHCP4_CLIENT_PORT = 68; /** * IEEE802.11 standard constants. * * See also: * - https://ieeexplore.ieee.org/document/7786995 */ public static final int VENDOR_SPECIFIC_IE_ID = 0xdd; /** * TrafficStats constants. */ // These tags are used by the network stack to do traffic for its own purposes. Traffic // tagged with these will be counted toward the network stack and must stay inside the // range defined by // {@link android.net.TrafficStats#TAG_NETWORK_STACK_RANGE_START} and // {@link android.net.TrafficStats#TAG_NETWORK_STACK_RANGE_END}. public static final int TAG_SYSTEM_DHCP = 0xFFFFFE01; public static final int TAG_SYSTEM_NEIGHBOR = 0xFFFFFE02; public static final int TAG_SYSTEM_DHCP_SERVER = 0xFFFFFE03; // These tags are used by the network stack to do traffic on behalf of apps. Traffic // tagged with these will be counted toward the app on behalf of which the network // stack is doing this traffic. These values must stay inside the range defined by // {@link android.net.TrafficStats#TAG_NETWORK_STACK_IMPERSONATION_RANGE_START} and // {@link android.net.TrafficStats#TAG_NETWORK_STACK_IMPERSONATION_RANGE_END}. public static final int TAG_SYSTEM_PROBE = 0xFFFFFF81; public static final int TAG_SYSTEM_DNS = 0xFFFFFF82; // TODO: Move to Inet4AddressUtils // See aosp/1455936: NetworkStackConstants can't depend on it as it causes jarjar-related issues // for users of both the net-utils-device-common and net-utils-framework-common libraries. // Jarjar rule management needs to be simplified for that: b/170445871 /** * Make an Inet4Address from 4 bytes in network byte order. */ private static Inet4Address makeInet4Address(byte b1, byte b2, byte b3, byte b4) { try { return (Inet4Address) InetAddress.getByAddress(new byte[] { b1, b2, b3, b4 }); } catch (UnknownHostException e) { throw new IllegalArgumentException("addr must be 4 bytes: this should never happen"); } } /** * Make an Inet6Address from 16 bytes in network byte order. */ private static Inet6Address makeInet6Address(byte[] bytes) { try { return (Inet6Address) InetAddress.getByAddress(bytes); } catch (UnknownHostException e) { throw new IllegalArgumentException("addr must be 16 bytes: this should never happen"); } } private NetworkStackConstants() { throw new UnsupportedOperationException("This class is not to be instantiated"); } }