diff options
Diffstat (limited to 'common/device/com/android/net/module/util/arp/ArpPacket.java')
| -rw-r--r-- | common/device/com/android/net/module/util/arp/ArpPacket.java | 171 |
1 files changed, 0 insertions, 171 deletions
diff --git a/common/device/com/android/net/module/util/arp/ArpPacket.java b/common/device/com/android/net/module/util/arp/ArpPacket.java deleted file mode 100644 index dab9694b..00000000 --- a/common/device/com/android/net/module/util/arp/ArpPacket.java +++ /dev/null @@ -1,171 +0,0 @@ -/* - * 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 com.android.net.module.util.arp; - -import static android.system.OsConstants.ETH_P_ARP; -import static android.system.OsConstants.ETH_P_IP; - -import static com.android.net.module.util.NetworkStackConstants.ARP_ETHER_IPV4_LEN; -import static com.android.net.module.util.NetworkStackConstants.ARP_HWTYPE_ETHER; -import static com.android.net.module.util.NetworkStackConstants.ARP_REPLY; -import static com.android.net.module.util.NetworkStackConstants.ARP_REQUEST; -import static com.android.net.module.util.NetworkStackConstants.ETHER_ADDR_LEN; -import static com.android.net.module.util.NetworkStackConstants.IPV4_ADDR_LEN; - -import android.net.MacAddress; - -import com.android.internal.annotations.VisibleForTesting; - -import java.net.Inet4Address; -import java.net.InetAddress; -import java.net.UnknownHostException; -import java.nio.BufferUnderflowException; -import java.nio.ByteBuffer; - -/** - * Defines basic data and operations needed to build and parse packets for the - * ARP protocol. - * - * @hide - */ -public class ArpPacket { - private static final String TAG = "ArpPacket"; - - public final short opCode; - public final Inet4Address senderIp; - public final Inet4Address targetIp; - public final MacAddress senderHwAddress; - public final MacAddress targetHwAddress; - - ArpPacket(short opCode, MacAddress senderHwAddress, Inet4Address senderIp, - MacAddress targetHwAddress, Inet4Address targetIp) { - this.opCode = opCode; - this.senderHwAddress = senderHwAddress; - this.senderIp = senderIp; - this.targetHwAddress = targetHwAddress; - this.targetIp = targetIp; - } - - /** - * Build an ARP packet from the required specified parameters. - */ - @VisibleForTesting - public static ByteBuffer buildArpPacket(final byte[] dstMac, final byte[] srcMac, - final byte[] targetIp, final byte[] targetHwAddress, byte[] senderIp, - final short opCode) { - final ByteBuffer buf = ByteBuffer.allocate(ARP_ETHER_IPV4_LEN); - - // Ether header - buf.put(dstMac); - buf.put(srcMac); - buf.putShort((short) ETH_P_ARP); - - // ARP header - buf.putShort((short) ARP_HWTYPE_ETHER); // hrd - buf.putShort((short) ETH_P_IP); // pro - buf.put((byte) ETHER_ADDR_LEN); // hln - buf.put((byte) IPV4_ADDR_LEN); // pln - buf.putShort(opCode); // op - buf.put(srcMac); // sha - buf.put(senderIp); // spa - buf.put(targetHwAddress); // tha - buf.put(targetIp); // tpa - buf.flip(); - return buf; - } - - /** - * Parse an ARP packet from a ByteBuffer object. - */ - @VisibleForTesting - public static ArpPacket parseArpPacket(final byte[] recvbuf, final int length) - throws ParseException { - try { - if (length < ARP_ETHER_IPV4_LEN || recvbuf.length < length) { - throw new ParseException("Invalid packet length: " + length); - } - - final ByteBuffer buffer = ByteBuffer.wrap(recvbuf, 0, length); - byte[] l2dst = new byte[ETHER_ADDR_LEN]; - byte[] l2src = new byte[ETHER_ADDR_LEN]; - buffer.get(l2dst); - buffer.get(l2src); - - final short etherType = buffer.getShort(); - if (etherType != ETH_P_ARP) { - throw new ParseException("Incorrect Ether Type: " + etherType); - } - - final short hwType = buffer.getShort(); - if (hwType != ARP_HWTYPE_ETHER) { - throw new ParseException("Incorrect HW Type: " + hwType); - } - - final short protoType = buffer.getShort(); - if (protoType != ETH_P_IP) { - throw new ParseException("Incorrect Protocol Type: " + protoType); - } - - final byte hwAddrLength = buffer.get(); - if (hwAddrLength != ETHER_ADDR_LEN) { - throw new ParseException("Incorrect HW address length: " + hwAddrLength); - } - - final byte ipAddrLength = buffer.get(); - if (ipAddrLength != IPV4_ADDR_LEN) { - throw new ParseException("Incorrect Protocol address length: " + ipAddrLength); - } - - final short opCode = buffer.getShort(); - if (opCode != ARP_REQUEST && opCode != ARP_REPLY) { - throw new ParseException("Incorrect opCode: " + opCode); - } - - byte[] senderHwAddress = new byte[ETHER_ADDR_LEN]; - byte[] senderIp = new byte[IPV4_ADDR_LEN]; - buffer.get(senderHwAddress); - buffer.get(senderIp); - - byte[] targetHwAddress = new byte[ETHER_ADDR_LEN]; - byte[] targetIp = new byte[IPV4_ADDR_LEN]; - buffer.get(targetHwAddress); - buffer.get(targetIp); - - return new ArpPacket(opCode, MacAddress.fromBytes(senderHwAddress), - (Inet4Address) InetAddress.getByAddress(senderIp), - MacAddress.fromBytes(targetHwAddress), - (Inet4Address) InetAddress.getByAddress(targetIp)); - } catch (IndexOutOfBoundsException e) { - throw new ParseException("Invalid index when wrapping a byte array into a buffer"); - } catch (BufferUnderflowException e) { - throw new ParseException("Invalid buffer position"); - } catch (IllegalArgumentException e) { - throw new ParseException("Invalid MAC address representation"); - } catch (UnknownHostException e) { - throw new ParseException("Invalid IP address of Host"); - } - } - - /** - * Thrown when parsing ARP packet failed. - */ - public static class ParseException extends Exception { - ParseException(String message) { - super(message); - } - } -} |