Move NetIdManager, ProfileNetworkPreferences

Move NetIdManager and ProfileNetworkPreferences from services/core to packages/Connectivity/service. This is a partial cherry-pick of a downstream change. Bug: 186628461 Test: m Merged-In: I454e8a0a8d0e0f9e6d21a8e8faf5a9e299962ad4 Change-Id: I6734c181dac39518b8d69be1e49d7f5f0a0a18da
2021-05-13 13:56:53 +00:00
parent 4febb21cb6
commit 648fa1675c
2 changed files with 0 additions and 0 deletions
--- a/service/src/com/android/server/NetIdManager.java
+++ b/service/src/com/android/server/NetIdManager.java
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2019 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.server;
+
+import android.annotation.NonNull;
+import android.net.ConnectivityManager;
+import android.util.SparseBooleanArray;
+
+import com.android.internal.annotations.GuardedBy;
+import com.android.internal.annotations.VisibleForTesting;
+
+/**
+ * Class used to reserve and release net IDs.
+ *
+ * <p>Instances of this class are thread-safe.
+ */
+public class NetIdManager {
+    // Sequence number for Networks; keep in sync with system/netd/NetworkController.cpp
+    public static final int MIN_NET_ID = 100; // some reserved marks
+    // Top IDs reserved by IpSecService
+    public static final int MAX_NET_ID = ConnectivityManager.getIpSecNetIdRange().getLower() - 1;
+
+    @GuardedBy("mNetIdInUse")
+    private final SparseBooleanArray mNetIdInUse = new SparseBooleanArray();
+
+    @GuardedBy("mNetIdInUse")
+    private int mLastNetId = MIN_NET_ID - 1;
+
+    private final int mMaxNetId;
+
+    public NetIdManager() {
+        this(MAX_NET_ID);
+    }
+
+    @VisibleForTesting
+    NetIdManager(int maxNetId) {
+        mMaxNetId = maxNetId;
+    }
+
+    /**
+     * Get the first netId that follows the provided lastId and is available.
+     */
+    private int getNextAvailableNetIdLocked(
+            int lastId, @NonNull SparseBooleanArray netIdInUse) {
+        int netId = lastId;
+        for (int i = MIN_NET_ID; i <= mMaxNetId; i++) {
+            netId = netId < mMaxNetId ? netId + 1 : MIN_NET_ID;
+            if (!netIdInUse.get(netId)) {
+                return netId;
+            }
+        }
+        throw new IllegalStateException("No free netIds");
+    }
+
+    /**
+     * Reserve a new ID for a network.
+     */
+    public int reserveNetId() {
+        synchronized (mNetIdInUse) {
+            mLastNetId = getNextAvailableNetIdLocked(mLastNetId, mNetIdInUse);
+            // Make sure NetID unused.  http://b/16815182
+            mNetIdInUse.put(mLastNetId, true);
+            return mLastNetId;
+        }
+    }
+
+    /**
+     * Clear a previously reserved ID for a network.
+     */
+    public void releaseNetId(int id) {
+        synchronized (mNetIdInUse) {
+            mNetIdInUse.delete(id);
+        }
+    }
+}