diff --git a/Tethering/apishim/30/com/android/networkstack/tethering/apishim/api30/BpfCoordinatorShimImpl.java b/Tethering/apishim/30/com/android/networkstack/tethering/apishim/api30/BpfCoordinatorShimImpl.java
index a33af61..26040a2 100644
--- a/Tethering/apishim/30/com/android/networkstack/tethering/apishim/api30/BpfCoordinatorShimImpl.java
+++ b/Tethering/apishim/30/com/android/networkstack/tethering/apishim/api30/BpfCoordinatorShimImpl.java
@@ -27,10 +27,10 @@
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import com.android.net.module.util.bpf.Tether4Key;
+import com.android.net.module.util.bpf.Tether4Value;
 import com.android.networkstack.tethering.BpfCoordinator.Dependencies;
 import com.android.networkstack.tethering.BpfCoordinator.Ipv6ForwardingRule;
-import com.android.networkstack.tethering.Tether4Key;
-import com.android.networkstack.tethering.Tether4Value;
 import com.android.networkstack.tethering.TetherStatsValue;
 
 import java.util.function.BiConsumer;
diff --git a/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java b/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
index 7189933..e3b1539 100644
--- a/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
+++ b/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
@@ -30,11 +30,11 @@
 import androidx.annotation.Nullable;
 
 import com.android.net.module.util.BpfMap;
+import com.android.net.module.util.bpf.Tether4Key;
+import com.android.net.module.util.bpf.Tether4Value;
 import com.android.networkstack.tethering.BpfCoordinator.Dependencies;
 import com.android.networkstack.tethering.BpfCoordinator.Ipv6ForwardingRule;
 import com.android.networkstack.tethering.BpfUtils;
-import com.android.networkstack.tethering.Tether4Key;
-import com.android.networkstack.tethering.Tether4Value;
 import com.android.networkstack.tethering.Tether6Value;
 import com.android.networkstack.tethering.TetherDevKey;
 import com.android.networkstack.tethering.TetherDevValue;
diff --git a/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java b/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java
index 08ab9ca..d663968 100644
--- a/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java
+++ b/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java
@@ -22,10 +22,10 @@
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import com.android.net.module.util.bpf.Tether4Key;
+import com.android.net.module.util.bpf.Tether4Value;
 import com.android.networkstack.tethering.BpfCoordinator.Dependencies;
 import com.android.networkstack.tethering.BpfCoordinator.Ipv6ForwardingRule;
-import com.android.networkstack.tethering.Tether4Key;
-import com.android.networkstack.tethering.Tether4Value;
 import com.android.networkstack.tethering.TetherStatsValue;
 
 import java.util.function.BiConsumer;
diff --git a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
index 8c8a2fd..40956f7 100644
--- a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
+++ b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
@@ -65,6 +65,8 @@
 import com.android.net.module.util.CollectionUtils;
 import com.android.net.module.util.NetworkStackConstants;
 import com.android.net.module.util.Struct;
+import com.android.net.module.util.bpf.Tether4Key;
+import com.android.net.module.util.bpf.Tether4Value;
 import com.android.net.module.util.netlink.ConntrackMessage;
 import com.android.net.module.util.netlink.NetlinkConstants;
 import com.android.net.module.util.netlink.NetlinkSocket;
diff --git a/Tethering/src/com/android/networkstack/tethering/Tether4Key.java b/Tethering/src/com/android/networkstack/tethering/Tether4Key.java
deleted file mode 100644
index a01ea34..0000000
--- a/Tethering/src/com/android/networkstack/tethering/Tether4Key.java
+++ /dev/null
@@ -1,81 +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.networkstack.tethering;
-
-import android.net.MacAddress;
-
-import androidx.annotation.NonNull;
-
-import com.android.net.module.util.Struct;
-import com.android.net.module.util.Struct.Field;
-import com.android.net.module.util.Struct.Type;
-
-import java.net.Inet4Address;
-import java.net.UnknownHostException;
-import java.util.Objects;
-
-/** Key type for downstream & upstream IPv4 forwarding maps. */
-public class Tether4Key extends Struct {
-    @Field(order = 0, type = Type.U32)
-    public final long iif;
-
-    @Field(order = 1, type = Type.EUI48)
-    public final MacAddress dstMac;
-
-    @Field(order = 2, type = Type.U8, padding = 1)
-    public final short l4proto;
-
-    @Field(order = 3, type = Type.ByteArray, arraysize = 4)
-    public final byte[] src4;
-
-    @Field(order = 4, type = Type.ByteArray, arraysize = 4)
-    public final byte[] dst4;
-
-    @Field(order = 5, type = Type.UBE16)
-    public final int srcPort;
-
-    @Field(order = 6, type = Type.UBE16)
-    public final int dstPort;
-
-    public Tether4Key(final long iif, @NonNull final MacAddress dstMac, final short l4proto,
-            final byte[] src4, final byte[] dst4, final int srcPort,
-            final int dstPort) {
-        Objects.requireNonNull(dstMac);
-
-        this.iif = iif;
-        this.dstMac = dstMac;
-        this.l4proto = l4proto;
-        this.src4 = src4;
-        this.dst4 = dst4;
-        this.srcPort = srcPort;
-        this.dstPort = dstPort;
-    }
-
-    @Override
-    public String toString() {
-        try {
-            return String.format(
-                    "iif: %d, dstMac: %s, l4proto: %d, src4: %s, dst4: %s, "
-                            + "srcPort: %d, dstPort: %d",
-                    iif, dstMac, l4proto,
-                    Inet4Address.getByAddress(src4), Inet4Address.getByAddress(dst4),
-                    Short.toUnsignedInt((short) srcPort), Short.toUnsignedInt((short) dstPort));
-        } catch (UnknownHostException | IllegalArgumentException e) {
-            return String.format("Invalid IP address", e);
-        }
-    }
-}
diff --git a/Tethering/src/com/android/networkstack/tethering/Tether4Value.java b/Tethering/src/com/android/networkstack/tethering/Tether4Value.java
deleted file mode 100644
index 03a226c..0000000
--- a/Tethering/src/com/android/networkstack/tethering/Tether4Value.java
+++ /dev/null
@@ -1,97 +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.networkstack.tethering;
-
-import android.net.MacAddress;
-
-import androidx.annotation.NonNull;
-
-import com.android.net.module.util.Struct;
-import com.android.net.module.util.Struct.Field;
-import com.android.net.module.util.Struct.Type;
-
-import java.net.InetAddress;
-import java.net.UnknownHostException;
-import java.util.Objects;
-
-/** Value type for downstream & upstream IPv4 forwarding maps. */
-public class Tether4Value extends Struct {
-    @Field(order = 0, type = Type.U32)
-    public final long oif;
-
-    // The ethhdr struct which is defined in uapi/linux/if_ether.h
-    @Field(order = 1, type = Type.EUI48)
-    public final MacAddress ethDstMac;
-    @Field(order = 2, type = Type.EUI48)
-    public final MacAddress ethSrcMac;
-    @Field(order = 3, type = Type.UBE16)
-    public final int ethProto;  // Packet type ID field.
-
-    @Field(order = 4, type = Type.U16)
-    public final int pmtu;
-
-    @Field(order = 5, type = Type.ByteArray, arraysize = 16)
-    public final byte[] src46;
-
-    @Field(order = 6, type = Type.ByteArray, arraysize = 16)
-    public final byte[] dst46;
-
-    @Field(order = 7, type = Type.UBE16)
-    public final int srcPort;
-
-    @Field(order = 8, type = Type.UBE16)
-    public final int dstPort;
-
-    // TODO: consider using U64.
-    @Field(order = 9, type = Type.U63)
-    public final long lastUsed;
-
-    public Tether4Value(final long oif, @NonNull final MacAddress ethDstMac,
-            @NonNull final MacAddress ethSrcMac, final int ethProto, final int pmtu,
-            final byte[] src46, final byte[] dst46, final int srcPort,
-            final int dstPort, final long lastUsed) {
-        Objects.requireNonNull(ethDstMac);
-        Objects.requireNonNull(ethSrcMac);
-
-        this.oif = oif;
-        this.ethDstMac = ethDstMac;
-        this.ethSrcMac = ethSrcMac;
-        this.ethProto = ethProto;
-        this.pmtu = pmtu;
-        this.src46 = src46;
-        this.dst46 = dst46;
-        this.srcPort = srcPort;
-        this.dstPort = dstPort;
-        this.lastUsed = lastUsed;
-    }
-
-    @Override
-    public String toString() {
-        try {
-            return String.format(
-                    "oif: %d, ethDstMac: %s, ethSrcMac: %s, ethProto: %d, pmtu: %d, "
-                            + "src46: %s, dst46: %s, srcPort: %d, dstPort: %d, "
-                            + "lastUsed: %d",
-                    oif, ethDstMac, ethSrcMac, ethProto, pmtu,
-                    InetAddress.getByAddress(src46), InetAddress.getByAddress(dst46),
-                    Short.toUnsignedInt((short) srcPort), Short.toUnsignedInt((short) dstPort),
-                    lastUsed);
-        } catch (UnknownHostException | IllegalArgumentException e) {
-            return String.format("Invalid IP address", e);
-        }
-    }
-}
diff --git a/Tethering/tests/unit/src/android/net/ip/IpServerTest.java b/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
index 267c376..a3c46c2 100644
--- a/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
+++ b/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
@@ -101,11 +101,11 @@
 
 import com.android.net.module.util.BpfMap;
 import com.android.net.module.util.NetworkStackConstants;
+import com.android.net.module.util.bpf.Tether4Key;
+import com.android.net.module.util.bpf.Tether4Value;
 import com.android.networkstack.tethering.BpfCoordinator;
 import com.android.networkstack.tethering.BpfCoordinator.Ipv6ForwardingRule;
 import com.android.networkstack.tethering.PrivateAddressCoordinator;
-import com.android.networkstack.tethering.Tether4Key;
-import com.android.networkstack.tethering.Tether4Value;
 import com.android.networkstack.tethering.Tether6Value;
 import com.android.networkstack.tethering.TetherDevKey;
 import com.android.networkstack.tethering.TetherDevValue;
diff --git a/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java b/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java
index d51f6fd..6c7a66d 100644
--- a/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java
+++ b/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java
@@ -99,6 +99,8 @@
 import com.android.net.module.util.BpfMap;
 import com.android.net.module.util.CollectionUtils;
 import com.android.net.module.util.NetworkStackConstants;
+import com.android.net.module.util.bpf.Tether4Key;
+import com.android.net.module.util.bpf.Tether4Value;
 import com.android.net.module.util.netlink.ConntrackMessage;
 import com.android.net.module.util.netlink.NetlinkConstants;
 import com.android.net.module.util.netlink.NetlinkSocket;