diff --git a/staticlibs/device/com/android/net/module/util/netlink/NduseroptMessage.java b/staticlibs/device/com/android/net/module/util/netlink/NduseroptMessage.java
index bdf574db89..2e9a99bb06 100644
--- a/staticlibs/device/com/android/net/module/util/netlink/NduseroptMessage.java
+++ b/staticlibs/device/com/android/net/module/util/netlink/NduseroptMessage.java
@@ -20,6 +20,7 @@ import static android.system.OsConstants.AF_INET6;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.annotation.VisibleForTesting;
 
 import java.net.Inet6Address;
 import java.net.InetAddress;
@@ -63,6 +64,20 @@ public class NduseroptMessage extends NetlinkMessage {
     /** The IP address that sent the packet containing the option. */
     public final InetAddress srcaddr;
 
+    @VisibleForTesting
+    public NduseroptMessage(@NonNull final StructNlMsgHdr header, byte family, int optslen,
+            int ifindex, byte icmptype, byte icmpcode, @NonNull final NdOption option,
+            final InetAddress srcaddr) {
+        super(header);
+        this.family = family;
+        this.opts_len = optslen;
+        this.ifindex = ifindex;
+        this.icmp_type = icmptype;
+        this.icmp_code = icmpcode;
+        this.option = option;
+        this.srcaddr = srcaddr;
+    }
+
     NduseroptMessage(@NonNull StructNlMsgHdr header, @NonNull ByteBuffer buf)
             throws UnknownHostException {
         super(header);
diff --git a/staticlibs/device/com/android/net/module/util/netlink/RtNetlinkRouteMessage.java b/staticlibs/device/com/android/net/module/util/netlink/RtNetlinkRouteMessage.java
index b2b1e9302a..545afeaf6c 100644
--- a/staticlibs/device/com/android/net/module/util/netlink/RtNetlinkRouteMessage.java
+++ b/staticlibs/device/com/android/net/module/util/netlink/RtNetlinkRouteMessage.java
@@ -19,10 +19,8 @@ package com.android.net.module.util.netlink;
 import static android.system.OsConstants.AF_INET;
 import static android.system.OsConstants.AF_INET6;
 
-import static android.system.OsConstants.NETLINK_ROUTE;
 import static com.android.net.module.util.NetworkStackConstants.IPV4_ADDR_ANY;
 import static com.android.net.module.util.NetworkStackConstants.IPV6_ADDR_ANY;
-import static com.android.net.module.util.netlink.NetlinkConstants.hexify;
 import static com.android.net.module.util.netlink.NetlinkConstants.RTNL_FAMILY_IP6MR;
 
 import android.annotation.SuppressLint;
@@ -38,9 +36,6 @@ import java.net.Inet4Address;
 import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.nio.ByteBuffer;
-import java.nio.ByteOrder;
-import java.nio.IntBuffer;
-import java.util.Arrays;
 
 /**
  * A NetlinkMessage subclass for rtnetlink route messages.
@@ -86,18 +81,27 @@ public class RtNetlinkRouteMessage extends NetlinkMessage {
     private long mSinceLastUseMillis; // Milliseconds since the route was used,
                                       // for resolved multicast routes
 
-    public RtNetlinkRouteMessage(StructNlMsgHdr header, StructRtMsg rtMsg) {
+
+    @VisibleForTesting
+    public RtNetlinkRouteMessage(final StructNlMsgHdr header, final StructRtMsg rtMsg,
+            final IpPrefix source, final IpPrefix destination, final InetAddress gateway,
+            int iif, int oif, final StructRtaCacheInfo cacheInfo) {
         super(header);
         mRtmsg = rtMsg;
-        mSource = null;
-        mDestination = null;
-        mGateway = null;
-        mIifIndex = 0;
-        mOifIndex = 0;
-        mRtaCacheInfo = null;
+        mSource = source;
+        mDestination = destination;
+        mGateway = gateway;
+        mIifIndex = iif;
+        mOifIndex = oif;
+        mRtaCacheInfo = cacheInfo;
         mSinceLastUseMillis = -1;
     }
 
+    public RtNetlinkRouteMessage(StructNlMsgHdr header, StructRtMsg rtMsg) {
+        this(header, rtMsg, null /* source */, null /* destination */, null /* gateway */,
+                0 /* iif */, 0 /* oif */, null /* cacheInfo */);
+    }
+
     /**
      * Returns the rtnetlink family.
      */
diff --git a/staticlibs/device/com/android/net/module/util/netlink/StructRtMsg.java b/staticlibs/device/com/android/net/module/util/netlink/StructRtMsg.java
index 3cd729222b..6d9318c81e 100644
--- a/staticlibs/device/com/android/net/module/util/netlink/StructRtMsg.java
+++ b/staticlibs/device/com/android/net/module/util/netlink/StructRtMsg.java
@@ -18,6 +18,7 @@ package com.android.net.module.util.netlink;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.annotation.VisibleForTesting;
 
 import com.android.net.module.util.Struct;
 import com.android.net.module.util.Struct.Field;
@@ -57,8 +58,9 @@ public class StructRtMsg extends Struct {
     @Field(order = 8, type = Type.U32)
     public final long flags;
 
-    StructRtMsg(short family, short dstLen, short srcLen, short tos, short table, short protocol,
-            short scope, short type, long flags) {
+    @VisibleForTesting
+    public StructRtMsg(short family, short dstLen, short srcLen, short tos, short table,
+            short protocol, short scope, short type, long flags) {
         this.family = family;
         this.dstLen = dstLen;
         this.srcLen = srcLen;