diff options
Diffstat (limited to 'common/testutils/hostdevice/com/android/testutils/PacketFilter.kt')
| -rw-r--r-- | common/testutils/hostdevice/com/android/testutils/PacketFilter.kt | 148 |
1 files changed, 0 insertions, 148 deletions
diff --git a/common/testutils/hostdevice/com/android/testutils/PacketFilter.kt b/common/testutils/hostdevice/com/android/testutils/PacketFilter.kt deleted file mode 100644 index 1bb6d683..00000000 --- a/common/testutils/hostdevice/com/android/testutils/PacketFilter.kt +++ /dev/null @@ -1,148 +0,0 @@ -/* - * 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.testutils - -import java.net.Inet4Address -import java.util.function.Predicate - -// Some of the below constants are duplicated with NetworkStackConstants, but this is a hostdevice -// library usable for host-side tests, so device-side utils are not usable, and there is no -// host-side non-test library to host common constants. -private const val ETHER_TYPE_OFFSET = 12 -private const val ETHER_HEADER_LENGTH = 14 -private const val IPV4_PROTOCOL_OFFSET = ETHER_HEADER_LENGTH + 9 -private const val IPV6_PROTOCOL_OFFSET = ETHER_HEADER_LENGTH + 6 -private const val IPV4_CHECKSUM_OFFSET = ETHER_HEADER_LENGTH + 10 -private const val IPV4_DST_OFFSET = ETHER_HEADER_LENGTH + 16 -private const val IPV4_HEADER_LENGTH = 20 -private const val IPV6_HEADER_LENGTH = 40 -private const val IPV4_PAYLOAD_OFFSET = ETHER_HEADER_LENGTH + IPV4_HEADER_LENGTH -private const val IPV6_PAYLOAD_OFFSET = ETHER_HEADER_LENGTH + IPV6_HEADER_LENGTH -private const val UDP_HEADER_LENGTH = 8 -private const val BOOTP_OFFSET = IPV4_PAYLOAD_OFFSET + UDP_HEADER_LENGTH -private const val BOOTP_TID_OFFSET = BOOTP_OFFSET + 4 -private const val BOOTP_CLIENT_MAC_OFFSET = BOOTP_OFFSET + 28 -private const val DHCP_OPTIONS_OFFSET = BOOTP_OFFSET + 240 -private const val ARP_OPCODE_OFFSET = ETHER_HEADER_LENGTH + 6 - -/** - * A [Predicate] that matches a [ByteArray] if it contains the specified [bytes] at the specified - * [offset]. - */ -class OffsetFilter(val offset: Int, vararg val bytes: Byte) : Predicate<ByteArray> { - override fun test(packet: ByteArray) = - bytes.withIndex().all { it.value == packet[offset + it.index] } -} - -private class UdpPortFilter( - private val udpOffset: Int, - private val src: Short?, - private val dst: Short? -) : Predicate<ByteArray> { - override fun test(t: ByteArray): Boolean { - if (src != null && !OffsetFilter(udpOffset, - src.toInt().ushr(8).toByte(), src.toByte()).test(t)) { - return false - } - - if (dst != null && !OffsetFilter(udpOffset + 2, - dst.toInt().ushr(8).toByte(), dst.toByte()).test(t)) { - return false - } - return true - } -} - -/** - * A [Predicate] that matches ethernet-encapped packets that contain an UDP over IPv4 datagram. - */ -class IPv4UdpFilter @JvmOverloads constructor( - srcPort: Short? = null, - dstPort: Short? = null -) : Predicate<ByteArray> { - private val impl = OffsetFilter(ETHER_TYPE_OFFSET, 0x08, 0x00 /* IPv4 */).and( - OffsetFilter(IPV4_PROTOCOL_OFFSET, 17 /* UDP */)).and( - UdpPortFilter(IPV4_PAYLOAD_OFFSET, srcPort, dstPort)) - override fun test(t: ByteArray) = impl.test(t) -} - -/** - * A [Predicate] that matches ethernet-encapped packets that contain an UDP over IPv6 datagram. - */ -class IPv6UdpFilter @JvmOverloads constructor( - srcPort: Short? = null, - dstPort: Short? = null -) : Predicate<ByteArray> { - private val impl = OffsetFilter(ETHER_TYPE_OFFSET, 0x86.toByte(), 0xdd.toByte() /* IPv6 */).and( - OffsetFilter(IPV6_PROTOCOL_OFFSET, 17 /* UDP */)).and( - UdpPortFilter(IPV6_PAYLOAD_OFFSET, srcPort, dstPort)) - override fun test(t: ByteArray) = impl.test(t) -} - -/** - * A [Predicate] that matches ethernet-encapped packets sent to the specified IPv4 destination. - */ -class IPv4DstFilter(dst: Inet4Address) : Predicate<ByteArray> { - private val impl = OffsetFilter(IPV4_DST_OFFSET, *dst.address) - override fun test(t: ByteArray) = impl.test(t) -} - -/** - * A [Predicate] that matches ethernet-encapped ARP requests. - */ -class ArpRequestFilter : Predicate<ByteArray> { - private val impl = OffsetFilter(ETHER_TYPE_OFFSET, 0x08, 0x06 /* ARP */) - .and(OffsetFilter(ARP_OPCODE_OFFSET, 0x00, 0x01 /* request */)) - override fun test(t: ByteArray) = impl.test(t) -} - -/** - * A [Predicate] that matches ethernet-encapped DHCP packets sent from a DHCP client. - */ -class DhcpClientPacketFilter : Predicate<ByteArray> { - private val impl = IPv4UdpFilter(srcPort = 68, dstPort = 67) - override fun test(t: ByteArray) = impl.test(t) -} - -/** - * A [Predicate] that matches a [ByteArray] if it contains a ethernet-encapped DHCP packet that - * contains the specified option with the specified [bytes] as value. - */ -class DhcpOptionFilter(val option: Byte, vararg val bytes: Byte) : Predicate<ByteArray> { - override fun test(packet: ByteArray): Boolean { - val option = findDhcpOption(packet, option) ?: return false - return option.contentEquals(bytes) - } -} - -/** - * Find a DHCP option in a packet and return its value, if found. - */ -fun findDhcpOption(packet: ByteArray, option: Byte): ByteArray? = - findOptionOffset(packet, option, DHCP_OPTIONS_OFFSET)?.let { - val optionLen = packet[it + 1] - return packet.copyOfRange(it + 2 /* type, length bytes */, it + 2 + optionLen) - } - -private tailrec fun findOptionOffset(packet: ByteArray, option: Byte, searchOffset: Int): Int? { - if (packet.size <= searchOffset + 2 /* type, length bytes */) return null - - return if (packet[searchOffset] == option) searchOffset else { - val optionLen = packet[searchOffset + 1] - findOptionOffset(packet, option, searchOffset + 2 + optionLen) - } -} |