Add prefix_cacheinfo struct to parse PREFIX_CACHEINFO attribute.

Bug: 315069348
Test: TH
Change-Id: I6a2cd40ab81fa079cdd6bd309dd48387c6faf146
diff --git a/staticlibs/device/com/android/net/module/util/netlink/StructPrefixCacheInfo.java b/staticlibs/device/com/android/net/module/util/netlink/StructPrefixCacheInfo.java
new file mode 100644
index 0000000..cfaa6e1
--- /dev/null
+++ b/staticlibs/device/com/android/net/module/util/netlink/StructPrefixCacheInfo.java
@@ -0,0 +1,77 @@
+/*
+ * 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 com.android.net.module.util.netlink;
+
+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.nio.ByteBuffer;
+
+/**
+ * struct prefix_cacheinfo {
+ *     __u32 preferred_time;
+ *     __u32 valid_time;
+ * }
+ *
+ * see also:
+ *
+ *     include/uapi/linux/if_addr.h
+ *
+ * @hide
+ */
+public class StructPrefixCacheInfo extends Struct {
+    public static final int STRUCT_SIZE = 8;
+
+    @Field(order = 0, type = Type.U32)
+    public final long preferred_time;
+    @Field(order = 1, type = Type.U32)
+    public final long valid_time;
+
+    StructPrefixCacheInfo(long preferred, long valid) {
+        this.preferred_time = preferred;
+        this.valid_time = valid;
+    }
+
+    /**
+     * Parse a prefix_cacheinfo struct from a {@link ByteBuffer}.
+     *
+     * @param byteBuffer The buffer from which to parse the prefix_cacheinfo.
+     * @return the parsed prefix_cacheinfo struct, or throw IllegalArgumentException if the
+     *         prefix_cacheinfo struct could not be parsed successfully(for example, if it was
+     *         truncated).
+     */
+    public static StructPrefixCacheInfo parse(@NonNull final ByteBuffer byteBuffer) {
+        if (byteBuffer.remaining() < STRUCT_SIZE) {
+            throw new IllegalArgumentException("Invalid bytebuffer remaining size "
+                    + byteBuffer.remaining() + " for prefix_cacheinfo attribute");
+        }
+
+        // The ByteOrder must already have been set to native order.
+        return Struct.parse(StructPrefixCacheInfo.class, byteBuffer);
+    }
+
+    /**
+     * Write a prefix_cacheinfo struct to {@link ByteBuffer}.
+     */
+    public void pack(@NonNull final ByteBuffer byteBuffer) {
+        // The ByteOrder must already have been set to native order.
+        writeToByteBuffer(byteBuffer);
+    }
+}