| /* |
| * Copyright (C) 2019 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 android.net.netlink; |
| |
| import android.system.OsConstants; |
| import java.nio.ByteBuffer; |
| |
| |
| /** |
| * struct ndmsg |
| * |
| * see: <linux_src>/include/uapi/linux/neighbour.h |
| * |
| * @hide |
| */ |
| public class StructNdMsg { |
| // Already aligned. |
| public static final int STRUCT_SIZE = 12; |
| |
| // Neighbor Cache Entry States |
| public static final short NUD_NONE = 0x00; |
| public static final short NUD_INCOMPLETE = 0x01; |
| public static final short NUD_REACHABLE = 0x02; |
| public static final short NUD_STALE = 0x04; |
| public static final short NUD_DELAY = 0x08; |
| public static final short NUD_PROBE = 0x10; |
| public static final short NUD_FAILED = 0x20; |
| public static final short NUD_NOARP = 0x40; |
| public static final short NUD_PERMANENT = 0x80; |
| |
| public static String stringForNudState(short nudState) { |
| switch (nudState) { |
| case NUD_NONE: return "NUD_NONE"; |
| case NUD_INCOMPLETE: return "NUD_INCOMPLETE"; |
| case NUD_REACHABLE: return "NUD_REACHABLE"; |
| case NUD_STALE: return "NUD_STALE"; |
| case NUD_DELAY: return "NUD_DELAY"; |
| case NUD_PROBE: return "NUD_PROBE"; |
| case NUD_FAILED: return "NUD_FAILED"; |
| case NUD_NOARP: return "NUD_NOARP"; |
| case NUD_PERMANENT: return "NUD_PERMANENT"; |
| default: |
| return "unknown NUD state: " + String.valueOf(nudState); |
| } |
| } |
| |
| public static boolean isNudStateConnected(short nudState) { |
| return ((nudState & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)) != 0); |
| } |
| |
| public static boolean isNudStateValid(short nudState) { |
| return (isNudStateConnected(nudState) || |
| ((nudState & (NUD_PROBE|NUD_STALE|NUD_DELAY)) != 0)); |
| } |
| |
| // Neighbor Cache Entry Flags |
| public static byte NTF_USE = (byte) 0x01; |
| public static byte NTF_SELF = (byte) 0x02; |
| public static byte NTF_MASTER = (byte) 0x04; |
| public static byte NTF_PROXY = (byte) 0x08; |
| public static byte NTF_ROUTER = (byte) 0x80; |
| |
| public static String stringForNudFlags(byte flags) { |
| final StringBuilder sb = new StringBuilder(); |
| if ((flags & NTF_USE) != 0) { |
| sb.append("NTF_USE"); |
| } |
| if ((flags & NTF_SELF) != 0) { |
| if (sb.length() > 0) { sb.append("|"); } |
| sb.append("NTF_SELF"); |
| } |
| if ((flags & NTF_MASTER) != 0) { |
| if (sb.length() > 0) { sb.append("|"); } |
| sb.append("NTF_MASTER"); |
| } |
| if ((flags & NTF_PROXY) != 0) { |
| if (sb.length() > 0) { sb.append("|"); |
| } |
| sb.append("NTF_PROXY"); } |
| if ((flags & NTF_ROUTER) != 0) { |
| if (sb.length() > 0) { sb.append("|"); } |
| sb.append("NTF_ROUTER"); |
| } |
| return sb.toString(); |
| } |
| |
| private static boolean hasAvailableSpace(ByteBuffer byteBuffer) { |
| return byteBuffer != null && byteBuffer.remaining() >= STRUCT_SIZE; |
| } |
| |
| public static StructNdMsg parse(ByteBuffer byteBuffer) { |
| if (!hasAvailableSpace(byteBuffer)) { return null; } |
| |
| // The ByteOrder must have already been set by the caller. In most |
| // cases ByteOrder.nativeOrder() is correct, with the possible |
| // exception of usage within unittests. |
| final StructNdMsg struct = new StructNdMsg(); |
| struct.ndm_family = byteBuffer.get(); |
| final byte pad1 = byteBuffer.get(); |
| final short pad2 = byteBuffer.getShort(); |
| struct.ndm_ifindex = byteBuffer.getInt(); |
| struct.ndm_state = byteBuffer.getShort(); |
| struct.ndm_flags = byteBuffer.get(); |
| struct.ndm_type = byteBuffer.get(); |
| return struct; |
| } |
| |
| public byte ndm_family; |
| public int ndm_ifindex; |
| public short ndm_state; |
| public byte ndm_flags; |
| public byte ndm_type; |
| |
| public StructNdMsg() { |
| ndm_family = (byte) OsConstants.AF_UNSPEC; |
| } |
| |
| public void pack(ByteBuffer byteBuffer) { |
| // The ByteOrder must have already been set by the caller. In most |
| // cases ByteOrder.nativeOrder() is correct, with the exception |
| // of usage within unittests. |
| byteBuffer.put(ndm_family); |
| byteBuffer.put((byte) 0); // pad1 |
| byteBuffer.putShort((short) 0); // pad2 |
| byteBuffer.putInt(ndm_ifindex); |
| byteBuffer.putShort(ndm_state); |
| byteBuffer.put(ndm_flags); |
| byteBuffer.put(ndm_type); |
| } |
| |
| public boolean nudConnected() { |
| return isNudStateConnected(ndm_state); |
| } |
| |
| public boolean nudValid() { |
| return isNudStateValid(ndm_state); |
| } |
| |
| @Override |
| public String toString() { |
| final String stateStr = "" + ndm_state + " (" + stringForNudState(ndm_state) + ")"; |
| final String flagsStr = "" + ndm_flags + " (" + stringForNudFlags(ndm_flags) + ")"; |
| return "StructNdMsg{ " |
| + "family{" + NetlinkConstants.stringForAddressFamily((int) ndm_family) + "}, " |
| + "ifindex{" + ndm_ifindex + "}, " |
| + "state{" + stateStr + "}, " |
| + "flags{" + flagsStr + "}, " |
| + "type{" + ndm_type + "} " |
| + "}"; |
| } |
| } |