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

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;
 
@@ -155,14 +150,6 @@ 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}.
      *
@@ -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;
-    }
 }

core/jni/android_net_NetUtils.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2008, The Android Open Source Project
+ * Copyright 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.
@@ -28,7 +28,6 @@
 #include <netinet/udp.h>
 
 #include <DnsProxydProtocol.h> // NETID_USE_LOCAL_NAMESERVERS
-#include <android_runtime/AndroidRuntime.h>
 #include <cutils/properties.h>
 #include <nativehelper/JNIPlatformHelp.h>
 #include <nativehelper/ScopedLocalRef.h>
@@ -226,11 +225,6 @@ static jobject android_net_utils_getDnsNetwork(JNIEnv *env, jobject thiz) {
             class_Network, ctor, dnsNetId & ~NETID_USE_LOCAL_NAMESERVERS, privateDnsBypass);
 }
 
-static void android_net_utils_setAllowNetworkingForProcess(JNIEnv *env, jobject thiz,
-                                                           jboolean hasConnectivity) {
-    setAllowNetworkingForProcess(hasConnectivity == JNI_TRUE);
-}
-
 static jobject android_net_utils_getTcpRepairWindow(JNIEnv *env, jobject thiz, jobject javaFd) {
     if (javaFd == NULL) {
         jniThrowNullPointerException(env, NULL);
@@ -288,7 +282,6 @@ static const JNINativeMethod gNetworkUtilMethods[] = {
     { "resNetworkResult", "(Ljava/io/FileDescriptor;)Landroid/net/DnsResolver$DnsResponse;", (void*) android_net_utils_resNetworkResult },
     { "resNetworkCancel", "(Ljava/io/FileDescriptor;)V", (void*) android_net_utils_resNetworkCancel },
     { "getDnsNetwork", "()Landroid/net/Network;", (void*) android_net_utils_getDnsNetwork },
-    { "setAllowNetworkingForProcess", "(Z)V", (void *)android_net_utils_setAllowNetworkingForProcess },
 };
 // clang-format on
 

tests/net/java/android/net/NetworkUtilsTest.java

@@ -16,24 +16,10 @@
 
 package android.net;
 
-import static android.system.OsConstants.AF_INET;
-import static android.system.OsConstants.AF_INET6;
-import static android.system.OsConstants.AF_UNIX;
-import static android.system.OsConstants.EPERM;
-import static android.system.OsConstants.SOCK_DGRAM;
-import static android.system.OsConstants.SOCK_STREAM;
-
 import static junit.framework.Assert.assertEquals;
 
-import static org.junit.Assert.fail;
-
-import android.system.ErrnoException;
-import android.system.Os;
-
 import androidx.test.runner.AndroidJUnit4;
 
-import libcore.io.IoUtils;
-
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
@@ -139,50 +125,4 @@ public class NetworkUtilsTest {
         assertEquals(BigInteger.valueOf(7l - 4 + 4 + 16 + 65536),
                 NetworkUtils.routedIPv6AddressCount(set));
     }
-
-    private static void expectSocketSuccess(String msg, int domain, int type) {
-        try {
-            IoUtils.closeQuietly(Os.socket(domain, type, 0));
-        } catch (ErrnoException e) {
-            fail(msg + e.getMessage());
-        }
-    }
-
-    private static void expectSocketPemissionError(String msg, int domain, int type) {
-        try {
-            IoUtils.closeQuietly(Os.socket(domain, type, 0));
-            fail(msg);
-        } catch (ErrnoException e) {
-            assertEquals(msg, e.errno, EPERM);
-        }
-    }
-
-    private static void expectHasNetworking() {
-        expectSocketSuccess("Creating a UNIX socket should not have thrown ErrnoException",
-                AF_UNIX, SOCK_STREAM);
-        expectSocketSuccess("Creating a AF_INET socket shouldn't have thrown ErrnoException",
-                AF_INET, SOCK_DGRAM);
-        expectSocketSuccess("Creating a AF_INET6 socket shouldn't have thrown ErrnoException",
-                AF_INET6, SOCK_DGRAM);
-    }
-
-    private static void expectNoNetworking() {
-        expectSocketSuccess("Creating a UNIX socket should not have thrown ErrnoException",
-                AF_UNIX, SOCK_STREAM);
-        expectSocketPemissionError(
-                "Creating a AF_INET socket should have thrown ErrnoException(EPERM)",
-                AF_INET, SOCK_DGRAM);
-        expectSocketPemissionError(
-                "Creating a AF_INET6 socket should have thrown ErrnoException(EPERM)",
-                AF_INET6, SOCK_DGRAM);
-    }
-
-    @Test
-    public void testSetAllowNetworkingForProcess() {
-        expectHasNetworking();
-        NetworkUtils.setAllowNetworkingForProcess(false);
-        expectNoNetworking();
-        NetworkUtils.setAllowNetworkingForProcess(true);
-        expectHasNetworking();
-    }
 }

tests/net/java/com/android/internal/net/NetworkUtilsInternalTest.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2015 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 static android.system.OsConstants.AF_UNIX;
+import static android.system.OsConstants.EPERM;
+import static android.system.OsConstants.SOCK_DGRAM;
+import static android.system.OsConstants.SOCK_STREAM;
+
+import static junit.framework.Assert.assertEquals;
+
+import static org.junit.Assert.fail;
+
+import android.system.ErrnoException;
+import android.system.Os;
+
+import androidx.test.runner.AndroidJUnit4;
+
+import libcore.io.IoUtils;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+@androidx.test.filters.SmallTest
+public class NetworkUtilsInternalTest {
+
+    private static void expectSocketSuccess(String msg, int domain, int type) {
+        try {
+            IoUtils.closeQuietly(Os.socket(domain, type, 0));
+        } catch (ErrnoException e) {
+            fail(msg + e.getMessage());
+        }
+    }
+
+    private static void expectSocketPemissionError(String msg, int domain, int type) {
+        try {
+            IoUtils.closeQuietly(Os.socket(domain, type, 0));
+            fail(msg);
+        } catch (ErrnoException e) {
+            assertEquals(msg, e.errno, EPERM);
+        }
+    }
+
+    private static void expectHasNetworking() {
+        expectSocketSuccess("Creating a UNIX socket should not have thrown ErrnoException",
+                AF_UNIX, SOCK_STREAM);
+        expectSocketSuccess("Creating a AF_INET socket shouldn't have thrown ErrnoException",
+                AF_INET, SOCK_DGRAM);
+        expectSocketSuccess("Creating a AF_INET6 socket shouldn't have thrown ErrnoException",
+                AF_INET6, SOCK_DGRAM);
+    }
+
+    private static void expectNoNetworking() {
+        expectSocketSuccess("Creating a UNIX socket should not have thrown ErrnoException",
+                AF_UNIX, SOCK_STREAM);
+        expectSocketPemissionError(
+                "Creating a AF_INET socket should have thrown ErrnoException(EPERM)",
+                AF_INET, SOCK_DGRAM);
+        expectSocketPemissionError(
+                "Creating a AF_INET6 socket should have thrown ErrnoException(EPERM)",
+                AF_INET6, SOCK_DGRAM);
+    }
+
+    @Test
+    public void testSetAllowNetworkingForProcess() {
+        expectHasNetworking();
+        NetworkUtilsInternal.setAllowNetworkingForProcess(false);
+        expectNoNetworking();
+        NetworkUtilsInternal.setAllowNetworkingForProcess(true);
+        expectHasNetworking();
+    }
+}

tests/net/java/com/android/server/net/NetworkStatsCollectionTest.java

@@ -23,11 +23,11 @@ import static android.net.NetworkStats.TAG_NONE;
 import static android.net.NetworkStats.UID_ALL;
 import static android.net.NetworkStatsHistory.FIELD_ALL;
 import static android.net.NetworkTemplate.buildTemplateMobileAll;
-import static android.net.NetworkUtils.multiplySafeByRational;
 import static android.os.Process.myUid;
 import static android.text.format.DateUtils.HOUR_IN_MILLIS;
 import static android.text.format.DateUtils.MINUTE_IN_MILLIS;
 
+import static com.android.internal.net.NetworkUtilsInternal.multiplySafeByRational;
 import static com.android.testutils.MiscAsserts.assertThrows;
 
 import static org.junit.Assert.assertArrayEquals;