Split NetworkUtils and NetworkUtilsInternal

NetworkUtils is planned to move to a dedicated JAR for connectivity
classes, while NetworkUtilsInternal would stay in the
frameworks-minus-apex JAR, in the com.android.internal.net package.

Bug: 171540887
Test: m, boots, wifi working
      atest FrameworksNetTests
Change-Id: I3d38d72ad23a4bf84af823c7baeb6fed25c0665f

5 files changed, 98 insertions, 74 deletions

diff --git a/core/java/android/app/admin/DevicePolicyManager.java b/core/java/android/app/admin/DevicePolicyManager.java
index 6edc8ea6a3a6..9acf675615a6 100644
--- a/core/java/android/app/admin/DevicePolicyManager.java
+++ b/core/java/android/app/admin/DevicePolicyManager.java
@@ -53,7 +53,6 @@ import android.content.pm.PackageManager.NameNotFoundException;
 import android.content.pm.ParceledListSlice;
 import android.content.pm.UserInfo;
 import android.graphics.Bitmap;
-import android.net.NetworkUtils;
 import android.net.PrivateDnsConnectivityChecker;
 import android.net.ProxyInfo;
 import android.net.Uri;
@@ -90,6 +89,7 @@ import android.util.ArraySet;
 import android.util.Log;
 
 import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.net.NetworkUtilsInternal;
 import com.android.internal.os.BackgroundThread;
 import com.android.internal.util.Preconditions;
 import com.android.org.conscrypt.TrustedCertificateStore;
@@ -11466,7 +11466,7 @@ public class DevicePolicyManager {
             return PRIVATE_DNS_SET_ERROR_FAILURE_SETTING;
         }
 
-        if (NetworkUtils.isWeaklyValidatedHostname(privateDnsHost)) {
+        if (NetworkUtilsInternal.isWeaklyValidatedHostname(privateDnsHost)) {
             if (!PrivateDnsConnectivityChecker.canConnectToPrivateDnsServer(privateDnsHost)) {
                 return PRIVATE_DNS_SET_ERROR_HOST_NOT_SERVING;
             }
diff --git a/core/java/android/net/NetworkStatsHistory.java b/core/java/android/net/NetworkStatsHistory.java
index fba75614342d..bf25602041cf 100644
--- a/core/java/android/net/NetworkStatsHistory.java
+++ b/core/java/android/net/NetworkStatsHistory.java
@@ -26,9 +26,9 @@ import static android.net.NetworkStatsHistory.DataStreamUtils.writeVarLongArray;
 import static android.net.NetworkStatsHistory.Entry.UNKNOWN;
 import static android.net.NetworkStatsHistory.ParcelUtils.readLongArray;
 import static android.net.NetworkStatsHistory.ParcelUtils.writeLongArray;
-import static android.net.NetworkUtils.multiplySafeByRational;
 import static android.text.format.DateUtils.SECOND_IN_MILLIS;
 
+import static com.android.internal.net.NetworkUtilsInternal.multiplySafeByRational;
 import static com.android.internal.util.ArrayUtils.total;
 
 import android.compat.annotation.UnsupportedAppUsage;
diff --git a/core/java/android/net/NetworkUtils.java b/core/java/android/net/NetworkUtils.java
index a0faafa779a8..2e9be6f6979e 100644
--- a/core/java/android/net/NetworkUtils.java
+++ b/core/java/android/net/NetworkUtils.java
@@ -16,14 +16,9 @@
 
 package android.net;
 
-import static android.system.OsConstants.AF_INET;
-import static android.system.OsConstants.AF_INET6;
-
-import android.annotation.NonNull;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.os.Build;
 import android.system.ErrnoException;
-import android.system.Os;
 import android.util.Log;
 import android.util.Pair;
 
@@ -156,14 +151,6 @@ public class NetworkUtils {
     public static native Network getDnsNetwork() throws ErrnoException;
 
     /**
-     * Allow/Disallow creating AF_INET/AF_INET6 sockets and DNS lookups for current process.
-     *
-     * @param allowNetworking whether to allow or disallow creating AF_INET/AF_INET6 sockets
-     *                        and DNS lookups.
-     */
-    public static native void setAllowNetworkingForProcess(boolean allowNetworking);
-
-    /**
      * Get the tcp repair window associated with the {@code fd}.
      *
      * @param fd the tcp socket's {@link FileDescriptor}.
@@ -452,60 +439,4 @@ public class NetworkUtils {
         return routedIPCount;
     }
 
-    private static final int[] ADDRESS_FAMILIES = new int[] {AF_INET, AF_INET6};
-
-    /**
-     * Returns true if the hostname is weakly validated.
-     * @param hostname Name of host to validate.
-     * @return True if it's a valid-ish hostname.
-     *
-     * @hide
-     */
-    public static boolean isWeaklyValidatedHostname(@NonNull String hostname) {
-        // TODO(b/34953048): Use a validation method that permits more accurate,
-        // but still inexpensive, checking of likely valid DNS hostnames.
-        final String weakHostnameRegex = "^[a-zA-Z0-9_.-]+$";
-        if (!hostname.matches(weakHostnameRegex)) {
-            return false;
-        }
-
-        for (int address_family : ADDRESS_FAMILIES) {
-            if (Os.inet_pton(address_family, hostname) != null) {
-                return false;
-            }
-        }
-
-        return true;
-    }
-
-    /**
-     * Safely multiple a value by a rational.
-     * <p>
-     * Internally it uses integer-based math whenever possible, but switches
-     * over to double-based math if values would overflow.
-     * @hide
-     */
-    public static long multiplySafeByRational(long value, long num, long den) {
-        if (den == 0) {
-            throw new ArithmeticException("Invalid Denominator");
-        }
-        long x = value;
-        long y = num;
-
-        // Logic shamelessly borrowed from Math.multiplyExact()
-        long r = x * y;
-        long ax = Math.abs(x);
-        long ay = Math.abs(y);
-        if (((ax | ay) >>> 31 != 0)) {
-            // Some bits greater than 2^31 that might cause overflow
-            // Check the result using the divide operator
-            // and check for the special case of Long.MIN_VALUE * -1
-            if (((y != 0) && (r / y != x)) ||
-                    (x == Long.MIN_VALUE && y == -1)) {
-                // Use double math to avoid overflowing
-                return (long) (((double) num / den) * value);
-            }
-        }
-        return r / den;
-    }
 }
diff --git a/core/java/com/android/internal/net/NetworkUtilsInternal.java b/core/java/com/android/internal/net/NetworkUtilsInternal.java
new file mode 100644
index 000000000000..571d7e721094
--- /dev/null
+++ b/core/java/com/android/internal/net/NetworkUtilsInternal.java
@@ -0,0 +1,92 @@
+/*
+ * 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.internal.net;
+
+import static android.system.OsConstants.AF_INET;
+import static android.system.OsConstants.AF_INET6;
+
+import android.annotation.NonNull;
+import android.system.Os;
+
+/** @hide */
+public class NetworkUtilsInternal {
+
+    private static final int[] ADDRESS_FAMILIES = new int[] {AF_INET, AF_INET6};
+
+    /**
+     * Allow/Disallow creating AF_INET/AF_INET6 sockets and DNS lookups for current process.
+     *
+     * @param allowNetworking whether to allow or disallow creating AF_INET/AF_INET6 sockets
+     *                        and DNS lookups.
+     */
+    public static native void setAllowNetworkingForProcess(boolean allowNetworking);
+
+    /**
+     * Returns true if the hostname is weakly validated.
+     * @param hostname Name of host to validate.
+     * @return True if it's a valid-ish hostname.
+     *
+     * @hide
+     */
+    public static boolean isWeaklyValidatedHostname(@NonNull String hostname) {
+        // TODO(b/34953048): Use a validation method that permits more accurate,
+        // but still inexpensive, checking of likely valid DNS hostnames.
+        final String weakHostnameRegex = "^[a-zA-Z0-9_.-]+$";
+        if (!hostname.matches(weakHostnameRegex)) {
+            return false;
+        }
+
+        for (int address_family : ADDRESS_FAMILIES) {
+            if (Os.inet_pton(address_family, hostname) != null) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Safely multiple a value by a rational.
+     * <p>
+     * Internally it uses integer-based math whenever possible, but switches
+     * over to double-based math if values would overflow.
+     * @hide
+     */
+    public static long multiplySafeByRational(long value, long num, long den) {
+        if (den == 0) {
+            throw new ArithmeticException("Invalid Denominator");
+        }
+        long x = value;
+        long y = num;
+
+        // Logic shamelessly borrowed from Math.multiplyExact()
+        long r = x * y;
+        long ax = Math.abs(x);
+        long ay = Math.abs(y);
+        if (((ax | ay) >>> 31 != 0)) {
+            // Some bits greater than 2^31 that might cause overflow
+            // Check the result using the divide operator
+            // and check for the special case of Long.MIN_VALUE * -1
+            if (((y != 0) && (r / y != x))
+                    || (x == Long.MIN_VALUE && y == -1)) {
+                // Use double math to avoid overflowing
+                return (long) (((double) num / den) * value);
+            }
+        }
+        return r / den;
+    }
+}
diff --git a/core/java/com/android/internal/os/Zygote.java b/core/java/com/android/internal/os/Zygote.java
index 15d4525ac884..0381a75d722b 100644
--- a/core/java/com/android/internal/os/Zygote.java
+++ b/core/java/com/android/internal/os/Zygote.java
@@ -24,7 +24,6 @@ import android.content.pm.ApplicationInfo;
 import android.net.Credentials;
 import android.net.LocalServerSocket;
 import android.net.LocalSocket;
-import android.net.NetworkUtils;
 import android.os.FactoryTest;
 import android.os.IVold;
 import android.os.Process;
@@ -35,6 +34,8 @@ import android.system.ErrnoException;
 import android.system.Os;
 import android.util.Log;
 
+import com.android.internal.net.NetworkUtilsInternal;
+
 import dalvik.annotation.optimization.FastNative;
 import dalvik.system.ZygoteHooks;
 
@@ -352,7 +353,7 @@ public final class Zygote {
 
             // If no GIDs were specified, don't make any permissions changes based on groups.
             if (gids != null && gids.length > 0) {
-                NetworkUtils.setAllowNetworkingForProcess(containsInetGid(gids));
+                NetworkUtilsInternal.setAllowNetworkingForProcess(containsInetGid(gids));
             }
         }