Java tutorial
/* * Copyright (C) 2011 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 android.net; import static android.content.pm.PackageManager.GET_SIGNATURES; import android.annotation.SystemService; import android.annotation.UnsupportedAppUsage; import android.app.ActivityManager; import android.content.Context; import android.content.Intent; import android.content.pm.PackageManager; import android.content.pm.PackageManager.NameNotFoundException; import android.content.pm.Signature; import android.net.wifi.WifiConfiguration; import android.net.wifi.WifiInfo; import android.os.Build; import android.os.RemoteException; import android.os.UserHandle; import android.util.DebugUtils; import android.util.Pair; import android.util.Range; import com.google.android.collect.Sets; import java.time.ZonedDateTime; import java.util.HashSet; import java.util.Iterator; /** * Manager for creating and modifying network policy rules. * * {@hide} */ @SystemService(Context.NETWORK_POLICY_SERVICE) public class NetworkPolicyManager { /* POLICY_* are masks and can be ORed, although currently they are not.*/ /** No specific network policy, use system default. */ public static final int POLICY_NONE = 0x0; /** Reject network usage on metered networks when application in background. */ public static final int POLICY_REJECT_METERED_BACKGROUND = 0x1; /** Allow metered network use in the background even when in data usage save mode. */ public static final int POLICY_ALLOW_METERED_BACKGROUND = 0x4; /* * Rules defining whether an uid has access to a network given its type (metered / non-metered). * * These rules are bits and can be used in bitmask operations; in particular: * - rule & RULE_MASK_METERED: returns the metered-networks status. * - rule & RULE_MASK_ALL: returns the all-networks status. * * The RULE_xxx_ALL rules applies to all networks (metered or non-metered), but on * metered networks, the RULE_xxx_METERED rules should be checked first. For example, * if the device is on Battery Saver Mode and Data Saver Mode simulatenously, and a uid * is whitelisted for the former but not the latter, its status would be * RULE_REJECT_METERED | RULE_ALLOW_ALL, meaning it could have access to non-metered * networks but not to metered networks. * * See network-policy-restrictions.md for more info. */ /** No specific rule was set */ public static final int RULE_NONE = 0; /** Allow traffic on metered networks. */ public static final int RULE_ALLOW_METERED = 1 << 0; /** Temporarily allow traffic on metered networks because app is on foreground. */ public static final int RULE_TEMPORARY_ALLOW_METERED = 1 << 1; /** Reject traffic on metered networks. */ public static final int RULE_REJECT_METERED = 1 << 2; /** Network traffic should be allowed on all networks (metered or non-metered), although * metered-network restrictions could still apply. */ public static final int RULE_ALLOW_ALL = 1 << 5; /** Reject traffic on all networks. */ public static final int RULE_REJECT_ALL = 1 << 6; /** Mask used to get the {@code RULE_xxx_METERED} rules */ public static final int MASK_METERED_NETWORKS = 0b00001111; /** Mask used to get the {@code RULE_xxx_ALL} rules */ public static final int MASK_ALL_NETWORKS = 0b11110000; public static final int FIREWALL_RULE_DEFAULT = 0; public static final String FIREWALL_CHAIN_NAME_NONE = "none"; public static final String FIREWALL_CHAIN_NAME_DOZABLE = "dozable"; public static final String FIREWALL_CHAIN_NAME_STANDBY = "standby"; public static final String FIREWALL_CHAIN_NAME_POWERSAVE = "powersave"; private static final boolean ALLOW_PLATFORM_APP_POLICY = true; public static final int FOREGROUND_THRESHOLD_STATE = ActivityManager.PROCESS_STATE_BOUND_FOREGROUND_SERVICE; /** * {@link Intent} extra that indicates which {@link NetworkTemplate} rule it * applies to. */ public static final String EXTRA_NETWORK_TEMPLATE = "android.net.NETWORK_TEMPLATE"; public static final int OVERRIDE_UNMETERED = 1 << 0; public static final int OVERRIDE_CONGESTED = 1 << 1; private final Context mContext; @UnsupportedAppUsage private INetworkPolicyManager mService; public NetworkPolicyManager(Context context, INetworkPolicyManager service) { if (service == null) { throw new IllegalArgumentException("missing INetworkPolicyManager"); } mContext = context; mService = service; } @UnsupportedAppUsage public static NetworkPolicyManager from(Context context) { return (NetworkPolicyManager) context.getSystemService(Context.NETWORK_POLICY_SERVICE); } /** * Set policy flags for specific UID. * * @param policy should be {@link #POLICY_NONE} or any combination of {@code POLICY_} flags, * although it is not validated. */ @UnsupportedAppUsage public void setUidPolicy(int uid, int policy) { try { mService.setUidPolicy(uid, policy); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } /** * Add policy flags for specific UID. * * <p>The given policy bits will be set for the uid. * * @param policy should be {@link #POLICY_NONE} or any combination of {@code POLICY_} flags, * although it is not validated. */ public void addUidPolicy(int uid, int policy) { try { mService.addUidPolicy(uid, policy); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } /** * Clear/remove policy flags for specific UID. * * <p>The given policy bits will be set for the uid. * * @param policy should be {@link #POLICY_NONE} or any combination of {@code POLICY_} flags, * although it is not validated. */ public void removeUidPolicy(int uid, int policy) { try { mService.removeUidPolicy(uid, policy); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } @UnsupportedAppUsage public int getUidPolicy(int uid) { try { return mService.getUidPolicy(uid); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } @UnsupportedAppUsage public int[] getUidsWithPolicy(int policy) { try { return mService.getUidsWithPolicy(policy); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) public void registerListener(INetworkPolicyListener listener) { try { mService.registerListener(listener); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023) public void unregisterListener(INetworkPolicyListener listener) { try { mService.unregisterListener(listener); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } public void setNetworkPolicies(NetworkPolicy[] policies) { try { mService.setNetworkPolicies(policies); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } @UnsupportedAppUsage public NetworkPolicy[] getNetworkPolicies() { try { return mService.getNetworkPolicies(mContext.getOpPackageName()); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } @UnsupportedAppUsage public void setRestrictBackground(boolean restrictBackground) { try { mService.setRestrictBackground(restrictBackground); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } @UnsupportedAppUsage public boolean getRestrictBackground() { try { return mService.getRestrictBackground(); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } /** * Resets network policy settings back to factory defaults. * * @hide */ public void factoryReset(String subscriber) { try { mService.factoryReset(subscriber); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } /** {@hide} */ @Deprecated public static Iterator<Pair<ZonedDateTime, ZonedDateTime>> cycleIterator(NetworkPolicy policy) { final Iterator<Range<ZonedDateTime>> it = policy.cycleIterator(); return new Iterator<Pair<ZonedDateTime, ZonedDateTime>>() { @Override public boolean hasNext() { return it.hasNext(); } @Override public Pair<ZonedDateTime, ZonedDateTime> next() { if (hasNext()) { final Range<ZonedDateTime> r = it.next(); return Pair.create(r.getLower(), r.getUpper()); } else { return Pair.create(null, null); } } }; } /** * Check if given UID can have a {@link #setUidPolicy(int, int)} defined, * usually to protect critical system services. */ @Deprecated public static boolean isUidValidForPolicy(Context context, int uid) { // first, quick-reject non-applications if (!UserHandle.isApp(uid)) { return false; } if (!ALLOW_PLATFORM_APP_POLICY) { final PackageManager pm = context.getPackageManager(); final HashSet<Signature> systemSignature; try { systemSignature = Sets.newHashSet(pm.getPackageInfo("android", GET_SIGNATURES).signatures); } catch (NameNotFoundException e) { throw new RuntimeException("problem finding system signature", e); } try { // reject apps signed with platform cert for (String packageName : pm.getPackagesForUid(uid)) { final HashSet<Signature> packageSignature = Sets .newHashSet(pm.getPackageInfo(packageName, GET_SIGNATURES).signatures); if (packageSignature.containsAll(systemSignature)) { return false; } } } catch (NameNotFoundException e) { } } // nothing found above; we can apply policy to UID return true; } /** * @hide */ public static String uidRulesToString(int uidRules) { final StringBuilder string = new StringBuilder().append(uidRules).append(" ("); if (uidRules == RULE_NONE) { string.append("NONE"); } else { string.append(DebugUtils.flagsToString(NetworkPolicyManager.class, "RULE_", uidRules)); } string.append(")"); return string.toString(); } /** * @hide */ public static String uidPoliciesToString(int uidPolicies) { final StringBuilder string = new StringBuilder().append(uidPolicies).append(" ("); if (uidPolicies == POLICY_NONE) { string.append("NONE"); } else { string.append(DebugUtils.flagsToString(NetworkPolicyManager.class, "POLICY_", uidPolicies)); } string.append(")"); return string.toString(); } /** * Returns true if {@param procState} is considered foreground and as such will be allowed * to access network when the device is idle or in battery saver mode. Otherwise, false. */ public static boolean isProcStateAllowedWhileIdleOrPowerSaveMode(int procState) { return procState <= FOREGROUND_THRESHOLD_STATE; } /** * Returns true if {@param procState} is considered foreground and as such will be allowed * to access network when the device is in data saver mode. Otherwise, false. */ public static boolean isProcStateAllowedWhileOnRestrictBackground(int procState) { return procState <= FOREGROUND_THRESHOLD_STATE; } public static String resolveNetworkId(WifiConfiguration config) { return WifiInfo.removeDoubleQuotes(config.isPasspoint() ? config.providerFriendlyName : config.SSID); } public static String resolveNetworkId(String ssid) { return WifiInfo.removeDoubleQuotes(ssid); } /** {@hide} */ public static class Listener extends INetworkPolicyListener.Stub { @Override public void onUidRulesChanged(int uid, int uidRules) { } @Override public void onMeteredIfacesChanged(String[] meteredIfaces) { } @Override public void onRestrictBackgroundChanged(boolean restrictBackground) { } @Override public void onUidPoliciesChanged(int uid, int uidPolicies) { } @Override public void onSubscriptionOverride(int subId, int overrideMask, int overrideValue) { } } }