| /* |
| * Copyright (C) 2024 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.apf; |
| |
| import static android.system.OsConstants.IPPROTO_ICMPV6; |
| |
| import static com.android.net.module.util.NetworkStackConstants.ETHER_HEADER_LEN; |
| import static com.android.net.module.util.NetworkStackConstants.IPV4_HEADER_MIN_LEN; |
| import static com.android.net.module.util.NetworkStackConstants.IPV4_IGMP_TYPE_V1_REPORT; |
| import static com.android.net.module.util.NetworkStackConstants.IPV4_IGMP_TYPE_V2_JOIN_REPORT; |
| import static com.android.net.module.util.NetworkStackConstants.IPV4_IGMP_TYPE_V2_LEAVE_REPORT; |
| import static com.android.net.module.util.NetworkStackConstants.IPV4_IGMP_TYPE_V3_REPORT; |
| import static com.android.net.module.util.NetworkStackConstants.IPV4_OPTION_LEN_ROUTER_ALERT; |
| import static com.android.net.module.util.NetworkStackConstants.IPV4_OPTION_TYPE_ROUTER_ALERT; |
| |
| import android.net.InetAddresses; |
| |
| import java.nio.ByteBuffer; |
| import java.nio.ByteOrder; |
| import java.util.Set; |
| |
| /** |
| * The class which declares constants used in ApfFilter and unit tests. |
| */ |
| public final class ApfConstants { |
| |
| private ApfConstants() {} |
| public static final int ETH_HEADER_LEN = 14; |
| public static final int ETH_DEST_ADDR_OFFSET = 0; |
| public static final int ETH_ETHERTYPE_OFFSET = 12; |
| public static final int ETH_TYPE_MIN = 0x0600; |
| public static final int ETH_TYPE_MAX = 0xFFFF; |
| // TODO: Make these offsets relative to end of link-layer header; don't include ETH_HEADER_LEN. |
| public static final int IPV4_TOTAL_LENGTH_OFFSET = ETH_HEADER_LEN + 2; |
| public static final int IPV4_FRAGMENT_OFFSET_OFFSET = ETH_HEADER_LEN + 6; |
| // Endianness is not an issue for this constant because the APF interpreter always operates in |
| // network byte order. |
| public static final int IPV4_FRAGMENT_OFFSET_MASK = 0x1fff; |
| public static final int IPV4_FRAGMENT_MORE_FRAGS_MASK = 0x2000; |
| public static final int IPV4_PROTOCOL_OFFSET = ETH_HEADER_LEN + 9; |
| public static final int IPV4_SRC_ADDR_OFFSET = ETH_HEADER_LEN + 12; |
| public static final int IPV4_DEST_ADDR_OFFSET = ETH_HEADER_LEN + 16; |
| public static final int IPV4_ANY_HOST_ADDRESS = 0; |
| public static final int IPV4_BROADCAST_ADDRESS = -1; // 255.255.255.255 |
| // The IPv4 all hosts destination 224.0.0.1 |
| public static final byte[] IPV4_ALL_HOSTS_ADDRESS = |
| InetAddresses.parseNumericAddress("224.0.0.1").getAddress(); |
| // The IPv4 all multicast routers destination 224.0.0.22 |
| public static final byte[] IPV4_ALL_IGMPV3_MULTICAST_ROUTERS_ADDRESS = |
| InetAddresses.parseNumericAddress("224.0.0.22").getAddress(); |
| public static long IPV4_ALL_HOSTS_ADDRESS_IN_LONG = 0xe0000001L; // 224.0.0.1 |
| public static final int IPV4_IGMP_TYPE_QUERY = 0x11; |
| public static final Set<Long> IGMP_TYPE_REPORTS = Set.of( |
| (long) IPV4_IGMP_TYPE_V1_REPORT, |
| (long) IPV4_IGMP_TYPE_V2_JOIN_REPORT, |
| (long) IPV4_IGMP_TYPE_V2_LEAVE_REPORT, |
| (long) IPV4_IGMP_TYPE_V3_REPORT); |
| public static final byte[] IPV4_ROUTER_ALERT_OPTION = { |
| (byte) IPV4_OPTION_TYPE_ROUTER_ALERT, // option type |
| (byte) IPV4_OPTION_LEN_ROUTER_ALERT, // option length |
| 0, 0 // option value |
| }; |
| public static final int IPV4_ROUTER_ALERT_OPTION_LEN = 4; |
| public static final int IGMP_CHECKSUM_WITH_ROUTER_ALERT_OFFSET = |
| ETHER_HEADER_LEN + IPV4_HEADER_MIN_LEN + IPV4_ROUTER_ALERT_OPTION_LEN + 2; |
| public static final byte[] IGMPV2_REPORT_FROM_IPV4_OPTION_TO_IGMP_CHECKSUM = { |
| // option type |
| (byte) IPV4_OPTION_TYPE_ROUTER_ALERT, |
| // option length |
| (byte) IPV4_OPTION_LEN_ROUTER_ALERT, |
| // option value |
| 0, 0, |
| // IGMP type |
| // Indicating an IGMPv2 Membership Report (Join Group) |
| (byte) IPV4_IGMP_TYPE_V2_JOIN_REPORT, |
| // max response time |
| // Typically used in IGMP queries,but is not significant in IGMPv2 reports. |
| 0, |
| // checksum, calculate later |
| 0, 0 |
| }; |
| |
| // IGMPv3 group record types |
| // From include/uapi/linux/igmp.h |
| public static final int IGMPV3_MODE_IS_EXCLUDE = 2; |
| |
| // MLDv2 group record types |
| // From include/uapi/linux/icmpv6.h |
| public static final int MLD2_MODE_IS_EXCLUDE = 2; |
| |
| // Traffic class and Flow label are not byte aligned. Luckily we |
| // don't care about either value so we'll consider bytes 1-3 of the |
| // IPv6 header as don't care. |
| public static final int IPV6_FLOW_LABEL_OFFSET = ETH_HEADER_LEN + 1; |
| public static final int IPV6_FLOW_LABEL_LEN = 3; |
| public static final int IPV6_PAYLOAD_LEN_OFFSET = ETH_HEADER_LEN + 4; |
| public static final int IPV6_NEXT_HEADER_OFFSET = ETH_HEADER_LEN + 6; |
| public static final int IPV6_HOP_LIMIT_OFFSET = ETH_HEADER_LEN + 7; |
| public static final int IPV6_SRC_ADDR_OFFSET = ETH_HEADER_LEN + 8; |
| public static final int IPV6_DEST_ADDR_OFFSET = ETH_HEADER_LEN + 24; |
| public static final int IPV6_HEADER_LEN = 40; |
| // The IPv6 all nodes address ff02::1 |
| public static final byte[] IPV6_ALL_NODES_ADDRESS = |
| { (byte) 0xff, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 }; |
| // The IPv6 unspecified address :: |
| public static final byte[] IPV6_UNSPECIFIED_ADDRESS = |
| {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; |
| // The IPv6 solicited nodes multicast address prefix ff02::1:ffXX:X/104 |
| public static final byte[] IPV6_SOLICITED_NODES_PREFIX = |
| { (byte) 0xff, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, (byte) 0xff}; |
| public static final byte[] IPV6_MLD_V2_ALL_ROUTERS_MULTICAST_ADDRESS = |
| { (byte) 0xff, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (byte) 0x16 }; |
| |
| /** |
| * IPv6 Router Alert Option constants. |
| * |
| * See also: |
| * - https://tools.ietf.org/html/rfc2711 |
| */ |
| public static final int IPV6_ROUTER_ALERT_OPTION_TYPE = 5; |
| public static final int IPV6_ROUTER_ALERT_OPTION_LEN = 2; |
| |
| /** |
| * IPv6 MLD constants. |
| * |
| * See also: |
| * - https://tools.ietf.org/html/rfc2710 |
| * - https://tools.ietf.org/html/rfc3810 |
| */ |
| public static final int IPV6_MLD_MESSAGE_MIN_SIZE = 8; |
| public static final int IPV6_MLD_MIN_SIZE = 24; |
| public static final int IPV6_MLD_TYPE_QUERY = 130; |
| public static final int IPV6_MLD_TYPE_V1_REPORT = 131; |
| public static final int IPV6_MLD_TYPE_V1_DONE = 132; |
| public static final int IPV6_MLD_TYPE_V2_REPORT = 143; |
| public static final int IPV6_MLD_V2_MULTICAST_ADDRESS_RECORD_SIZE = 20; |
| // kernel reference: net/ipv6/mcast.c#igmp6_send() |
| public static final byte[] IPV6_MLD_HOPOPTS = { |
| (byte) IPPROTO_ICMPV6, // next header type |
| 0, // next header length |
| (byte) IPV6_ROUTER_ALERT_OPTION_TYPE, // Router Alert option type |
| (byte) IPV6_ROUTER_ALERT_OPTION_LEN, // Router Alert option length |
| 0, 0, // Router Alert option value |
| (byte) 0x01, (byte) 0x00 // PadN type and length |
| }; |
| |
| public static final Set<Long> IPV6_MLD_TYPE_REPORTS = Set.of( |
| (long) IPV6_MLD_TYPE_V1_REPORT, |
| (long) IPV6_MLD_TYPE_V1_DONE, |
| (long) IPV6_MLD_TYPE_V2_REPORT |
| ); |
| public static final int IPV6_EXT_HEADER_OFFSET = ETH_HEADER_LEN + IPV6_HEADER_LEN; |
| public static final int IPV6_MLD_CHECKSUM_OFFSET = |
| ETHER_HEADER_LEN + IPV6_HEADER_LEN + IPV6_MLD_HOPOPTS.length + 2; |
| public static final int IPV6_MLD_TYPE_OFFSET = |
| IPV6_EXT_HEADER_OFFSET + IPV6_MLD_HOPOPTS.length; |
| public static final int IPV6_MLD_MULTICAST_ADDR_OFFSET = |
| IPV6_EXT_HEADER_OFFSET + IPV6_MLD_HOPOPTS.length + 8; |
| |
| public static final int ICMP4_TYPE_NO_OPTIONS_OFFSET = ETH_HEADER_LEN + IPV4_HEADER_MIN_LEN; |
| public static final int ICMP4_CHECKSUM_NO_OPTIONS_OFFSET = |
| ETH_HEADER_LEN + IPV4_HEADER_MIN_LEN + 2; |
| public static final int ICMP4_CONTENT_NO_OPTIONS_OFFSET = |
| ETH_HEADER_LEN + IPV4_HEADER_MIN_LEN + 4; |
| |
| public static final int ICMP6_ECHO_REQUEST_HEADER_LEN = 8; |
| public static final int ICMP6_TYPE_OFFSET = ETH_HEADER_LEN + IPV6_HEADER_LEN; |
| public static final int ICMP6_CODE_OFFSET = ETH_HEADER_LEN + IPV6_HEADER_LEN + 1; |
| public static final int ICMP6_CHECKSUM_OFFSET = ETH_HEADER_LEN + IPV6_HEADER_LEN + 2; |
| public static final int ICMP6_CONTENT_OFFSET = ETH_HEADER_LEN + IPV6_HEADER_LEN + 4; |
| public static final int ICMP6_NS_TARGET_IP_OFFSET = ICMP6_TYPE_OFFSET + 8; |
| public static final int ICMP6_NS_OPTION_TYPE_OFFSET = ICMP6_NS_TARGET_IP_OFFSET + 16; |
| // From RFC4861: |
| public static final int ICMP6_RA_HEADER_LEN = 16; |
| public static final int ICMP6_RA_CHECKSUM_OFFSET = |
| ETH_HEADER_LEN + IPV6_HEADER_LEN + 2; |
| public static final int ICMP6_RA_CHECKSUM_LEN = 2; |
| public static final int ICMP6_RA_OPTION_OFFSET = |
| ETH_HEADER_LEN + IPV6_HEADER_LEN + ICMP6_RA_HEADER_LEN; |
| public static final int ICMP6_RA_ROUTER_LIFETIME_OFFSET = |
| ETH_HEADER_LEN + IPV6_HEADER_LEN + 6; |
| public static final int ICMP6_RA_ROUTER_LIFETIME_LEN = 2; |
| // Prefix information option. |
| public static final int ICMP6_PREFIX_OPTION_TYPE = 3; |
| public static final int ICMP6_PREFIX_OPTION_VALID_LIFETIME_OFFSET = 4; |
| public static final int ICMP6_PREFIX_OPTION_VALID_LIFETIME_LEN = 4; |
| public static final int ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_LEN = 4; |
| |
| // From RFC4861: source link-layer address |
| public static final int ICMP6_SOURCE_LL_ADDRESS_OPTION_TYPE = 1; |
| // From RFC4861: mtu size option |
| public static final int ICMP6_MTU_OPTION_TYPE = 5; |
| // From RFC6106: Recursive DNS Server option |
| public static final int ICMP6_RDNSS_OPTION_TYPE = 25; |
| // From RFC5175: RA Flags Extension option |
| public static final int ICMP6_RA_FLAGS_EXTENSION_OPTION_TYPE = 26; |
| // From RFC6106: DNS Search List option |
| public static final int ICMP6_DNSSL_OPTION_TYPE = 31; |
| // From RFC8910: Captive-Portal option |
| public static final int ICMP6_CAPTIVE_PORTAL_OPTION_TYPE = 37; |
| // From RFC8781: PREF64 option |
| public static final int ICMP6_PREF64_OPTION_TYPE = 38; |
| |
| // From RFC4191: Route Information option |
| public static final int ICMP6_ROUTE_INFO_OPTION_TYPE = 24; |
| // Above three options all have the same format: |
| public static final int ICMP6_4_BYTE_LIFETIME_OFFSET = 4; |
| public static final int ICMP6_4_BYTE_LIFETIME_LEN = 4; |
| public static final int IPPROTO_HOPOPTS = 0; |
| |
| // NOTE: this must be added to the IPv4 header length in MemorySlot.IPV4_HEADER_SIZE |
| public static final int TCP_UDP_SOURCE_PORT_OFFSET = ETH_HEADER_LEN; |
| public static final int TCP_UDP_DESTINATION_PORT_OFFSET = ETH_HEADER_LEN + 2; |
| public static final int IGMP_MAX_RESP_TIME_OFFSET = ETHER_HEADER_LEN + 1; |
| public static final int IGMP_MULTICAST_ADDRESS_OFFSET = ETH_HEADER_LEN + 4; |
| public static final int UDP_HEADER_LEN = 8; |
| |
| public static final int TCP_HEADER_SIZE_OFFSET = 12; |
| |
| public static final int DHCP_SERVER_PORT = 67; |
| public static final int DHCP_CLIENT_PORT = 68; |
| |
| public static final int DNS_HEADER_LEN = 12; |
| public static final int IPV4_UDP_DESTINATION_PORT_NO_OPTIONS_OFFSET = |
| ETH_HEADER_LEN + IPV4_HEADER_MIN_LEN + 2; |
| public static final int IPV4_UDP_DESTINATION_CHECKSUM_NO_OPTIONS_OFFSET = |
| ETH_HEADER_LEN + IPV4_HEADER_MIN_LEN + 6; |
| public static final int IPV4_UDP_PAYLOAD_NO_OPTIONS_OFFSET = |
| ETH_HEADER_LEN + IPV4_HEADER_MIN_LEN + UDP_HEADER_LEN; |
| public static final int IPV4_DNS_QDCOUNT_NO_OPTIONS_OFFSET = |
| ETH_HEADER_LEN + IPV4_HEADER_MIN_LEN + UDP_HEADER_LEN + 4; |
| public static final int IPV6_UDP_DESTINATION_PORT_OFFSET = |
| ETH_HEADER_LEN + IPV6_HEADER_LEN + 2; |
| public static final int IPV6_UDP_DESTINATION_CHECKSUM_OFFSET = |
| ETH_HEADER_LEN + IPV6_HEADER_LEN + 6; |
| public static final int IPv6_UDP_PAYLOAD_OFFSET = |
| ETH_HEADER_LEN + IPV6_HEADER_LEN + UDP_HEADER_LEN; |
| public static final int IPV6_DNS_QDCOUNT_OFFSET = |
| ETH_HEADER_LEN + IPV6_HEADER_LEN + UDP_HEADER_LEN + 4; |
| |
| public static final int ARP_HEADER_OFFSET = ETH_HEADER_LEN; |
| public static final byte[] ARP_IPV4_HEADER = { |
| 0, 1, // Hardware type: Ethernet (1) |
| 8, 0, // Protocol type: IP (0x0800) |
| 6, // Hardware size: 6 |
| 4, // Protocol size: 4 |
| }; |
| public static final int ARP_OPCODE_OFFSET = ARP_HEADER_OFFSET + 6; |
| // Opcode: ARP request (0x0001), ARP reply (0x0002) |
| public static final short ARP_OPCODE_REQUEST = 1; |
| public static final short ARP_OPCODE_REPLY = 2; |
| public static final int ARP_SOURCE_IP_ADDRESS_OFFSET = ARP_HEADER_OFFSET + 14; |
| public static final int ARP_TARGET_IP_ADDRESS_OFFSET = ARP_HEADER_OFFSET + 24; |
| // Limit on the Black List size to cap on program usage for this |
| // TODO: Select a proper max length |
| public static final int APF_MAX_ETH_TYPE_BLACK_LIST_LEN = 20; |
| |
| // The ethernet solicited nodes multicast address prefix 33:33:FF:xx:xx:xx |
| public static final byte[] ETH_SOLICITED_NODES_PREFIX = |
| {(byte) 0x33, (byte) 0x33, (byte) 0xff}; |
| public static final byte[] ETH_MULTICAST_IPV6_ALL_NODES_MAC_ADDRESS = |
| { (byte) 0x33, (byte) 0x33, 0, 0, 0, 1}; |
| public static final byte[] ETH_MULTICAST_MDNS_V4_MAC_ADDRESS = |
| {(byte) 0x01, (byte) 0x00, (byte) 0x5e, (byte) 0x00, (byte) 0x00, (byte) 0xfb}; |
| public static final byte[] ETH_MULTICAST_MDNS_V6_MAC_ADDRESS = |
| {(byte) 0x33, (byte) 0x33, (byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0xfb}; |
| public static final byte[] ETH_MULTICAST_IGMP_V3_ALL_MULTICAST_ROUTERS_ADDRESS = |
| { (byte) 0x01, 0, (byte) 0x5e, 0, 0, (byte) 0x16}; |
| public static final byte[] ETH_MULTICAST_MLD_V2_ALL_MULTICAST_ROUTERS_ADDRESS = |
| { (byte) 0x33, (byte) 0x33, 0, 0, 0, (byte) 0x16}; |
| public static final int MDNS_PORT = 5353; |
| public static final byte[] MDNS_PORT_IN_BYTES = ByteBuffer.allocate(2).order( |
| ByteOrder.BIG_ENDIAN).putShort((short) MDNS_PORT).array(); |
| |
| public static final long MDNS_IPV4_ADDR_IN_LONG = 0xE00000FBL; // 224.0.0.251 |
| public static final byte[] MDNS_IPV4_ADDR = InetAddresses.parseNumericAddress( |
| "224.0.0.251").getAddress(); |
| public static final byte[] MDNS_IPV6_ADDR = InetAddresses.parseNumericAddress( |
| "FF02::FB").getAddress(); |
| public static final int ECHO_PORT = 7; |
| // NOTE: this must be added to the IPv4 header length in MemorySlot.IPV4_HEADER_SIZE, or the |
| // IPv6 header length. |
| public static final int DHCP_CLIENT_MAC_OFFSET = ETH_HEADER_LEN + UDP_HEADER_LEN + 28; |
| |
| /** |
| * Fixed byte sequence representing the following part of the ARP reply header: |
| * EtherType + HTYPE + PTYPE + HLEN + PLEN + ops reply (0x0002) |
| */ |
| public static final byte[] FIXED_ARP_REPLY_HEADER = |
| new byte[]{0x08, 0x06, 0x00, 0x01, 0x08, 0x00, 0x06, 0x04, 0x00, 0x02}; |
| } |
