/* * 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.server.connectivity; import static android.content.pm.PackageManager.PERMISSION_GRANTED; import static android.net.NattSocketKeepalive.NATT_PORT; import static android.net.NetworkAgent.CMD_ADD_KEEPALIVE_PACKET_FILTER; import static android.net.NetworkAgent.CMD_REMOVE_KEEPALIVE_PACKET_FILTER; import static android.net.NetworkAgent.CMD_START_SOCKET_KEEPALIVE; import static android.net.NetworkAgent.CMD_STOP_SOCKET_KEEPALIVE; import static android.net.SocketKeepalive.BINDER_DIED; import static android.net.SocketKeepalive.DATA_RECEIVED; import static android.net.SocketKeepalive.ERROR_INSUFFICIENT_RESOURCES; import static android.net.SocketKeepalive.ERROR_INVALID_INTERVAL; import static android.net.SocketKeepalive.ERROR_INVALID_IP_ADDRESS; import static android.net.SocketKeepalive.ERROR_INVALID_NETWORK; import static android.net.SocketKeepalive.ERROR_INVALID_SOCKET; import static android.net.SocketKeepalive.ERROR_UNSUPPORTED; import static android.net.SocketKeepalive.MAX_INTERVAL_SEC; import static android.net.SocketKeepalive.MIN_INTERVAL_SEC; import static android.net.SocketKeepalive.NO_KEEPALIVE; import static android.net.SocketKeepalive.SUCCESS; import android.annotation.NonNull; import android.annotation.Nullable; import android.content.Context; import android.net.ISocketKeepaliveCallback; import android.net.InvalidPacketException; import android.net.KeepalivePacketData; import android.net.NattKeepalivePacketData; import android.net.NetworkAgent; import android.net.NetworkUtils; import android.net.SocketKeepalive.InvalidSocketException; import android.net.TcpKeepalivePacketData; import android.net.util.IpUtils; import android.net.util.KeepaliveUtils; import android.os.Binder; import android.os.Handler; import android.os.IBinder; import android.os.Message; import android.os.Process; import android.os.RemoteException; import android.system.ErrnoException; import android.system.Os; import android.util.Log; import android.util.Pair; import com.android.internal.R; import com.android.internal.util.HexDump; import com.android.internal.util.IndentingPrintWriter; import java.io.FileDescriptor; import java.net.InetAddress; import java.net.InetSocketAddress; import java.net.SocketAddress; import java.util.ArrayList; import java.util.Arrays; import java.util.HashMap; /** * Manages socket keepalive requests. * * Provides methods to stop and start keepalive requests, and keeps track of keepalives across all * networks. This class is tightly coupled to ConnectivityService. It is not thread-safe and its * handle* methods must be called only from the ConnectivityService handler thread. */ public class KeepaliveTracker { private static final String TAG = "KeepaliveTracker"; private static final boolean DBG = false; public static final String PERMISSION = android.Manifest.permission.PACKET_KEEPALIVE_OFFLOAD; /** Keeps track of keepalive requests. */ private final HashMap > mKeepalives = new HashMap<> (); private final Handler mConnectivityServiceHandler; @NonNull private final TcpKeepaliveController mTcpController; @NonNull private final Context mContext; // Supported keepalive count for each transport type, can be configured through // config_networkSupportedKeepaliveCount. For better error handling, use // {@link getSupportedKeepalivesForNetworkCapabilities} instead of direct access. @NonNull private final int[] mSupportedKeepalives; // Reserved privileged keepalive slots per transport. Caller's permission will be enforced if // the number of remaining keepalive slots is less than or equal to the threshold. private final int mReservedPrivilegedSlots; // Allowed unprivileged keepalive slots per uid. Caller's permission will be enforced if // the number of remaining keepalive slots is less than or equal to the threshold. private final int mAllowedUnprivilegedSlotsForUid; public KeepaliveTracker(Context context, Handler handler) { mConnectivityServiceHandler = handler; mTcpController = new TcpKeepaliveController(handler); mContext = context; mSupportedKeepalives = KeepaliveUtils.getSupportedKeepalives(mContext); mReservedPrivilegedSlots = mContext.getResources().getInteger( R.integer.config_reservedPrivilegedKeepaliveSlots); mAllowedUnprivilegedSlotsForUid = mContext.getResources().getInteger( R.integer.config_allowedUnprivilegedKeepalivePerUid); } /** * Tracks information about a socket keepalive. * * All information about this keepalive is known at construction time except the slot number, * which is only returned when the hardware has successfully started the keepalive. */ class KeepaliveInfo implements IBinder.DeathRecipient { // Bookkeeping data. private final ISocketKeepaliveCallback mCallback; private final int mUid; private final int mPid; private final boolean mPrivileged; private final NetworkAgentInfo mNai; private final int mType; private final FileDescriptor mFd; public static final int TYPE_NATT = 1; public static final int TYPE_TCP = 2; // Keepalive slot. A small integer that identifies this keepalive among the ones handled // by this network. private int mSlot = NO_KEEPALIVE; // Packet data. private final KeepalivePacketData mPacket; private final int mInterval; // Whether the keepalive is started or not. The initial state is NOT_STARTED. private static final int NOT_STARTED = 1; private static final int STARTING = 2; private static final int STARTED = 3; private static final int STOPPING = 4; private int mStartedState = NOT_STARTED; KeepaliveInfo(@NonNull ISocketKeepaliveCallback callback, @NonNull NetworkAgentInfo nai, @NonNull KeepalivePacketData packet, int interval, int type, @Nullable FileDescriptor fd) throws InvalidSocketException { mCallback = callback; mPid = Binder.getCallingPid(); mUid = Binder.getCallingUid(); mPrivileged = (PERMISSION_GRANTED == mContext.checkPermission(PERMISSION, mPid, mUid)); mNai = nai; mPacket = packet; mInterval = interval; mType = type; // For SocketKeepalive, a dup of fd is kept in mFd so the source port from which the // keepalives are sent cannot be reused by another app even if the fd gets closed by // the user. A null is acceptable here for backward compatibility of PacketKeepalive // API. try { if (fd != null) { mFd = Os.dup(fd); } else { Log.d(TAG, toString() + " calls with null fd"); if (!mPrivileged) { throw new SecurityException( "null fd is not allowed for unprivileged access."); } if (mType == TYPE_TCP) { throw new IllegalArgumentException( "null fd is not allowed for tcp socket keepalives."); } mFd = null; } } catch (ErrnoException e) { Log.e(TAG, "Cannot dup fd: ", e); throw new InvalidSocketException(ERROR_INVALID_SOCKET, e); } try { mCallback.asBinder().linkToDeath(this, 0); } catch (RemoteException e) { binderDied(); } } public NetworkAgentInfo getNai() { return mNai; } private String startedStateString(final int state) { switch (state) { case NOT_STARTED : return "NOT_STARTED"; case STARTING : return "STARTING"; case STARTED : return "STARTED"; case STOPPING : return "STOPPING"; } throw new IllegalArgumentException("Unknown state"); } public String toString() { return "KeepaliveInfo [" + " type=" + mType + " network=" + mNai.network + " startedState=" + startedStateString(mStartedState) + " " + IpUtils.addressAndPortToString(mPacket.getSrcAddress(), mPacket.getSrcPort()) + "->" + IpUtils.addressAndPortToString(mPacket.getDstAddress(), mPacket.getDstPort()) + " interval=" + mInterval + " uid=" + mUid + " pid=" + mPid + " privileged=" + mPrivileged + " packetData=" + HexDump.toHexString(mPacket.getPacket()) + " ]"; } /** Called when the application process is killed. */ public void binderDied() { stop(BINDER_DIED); } void unlinkDeathRecipient() { if (mCallback != null) { mCallback.asBinder().unlinkToDeath(this, 0); } } private int checkNetworkConnected() { if (!mNai.networkInfo.isConnectedOrConnecting()) { return ERROR_INVALID_NETWORK; } return SUCCESS; } private int checkSourceAddress() { // Check that we have the source address. for (InetAddress address : mNai.linkProperties.getAddresses()) { if (address.equals(mPacket.getSrcAddress())) { return SUCCESS; } } return ERROR_INVALID_IP_ADDRESS; } private int checkInterval() { if (mInterval < MIN_INTERVAL_SEC || mInterval > MAX_INTERVAL_SEC) { return ERROR_INVALID_INTERVAL; } return SUCCESS; } private int checkPermission() { final HashMap networkKeepalives = mKeepalives.get(mNai); if (networkKeepalives == null) { return ERROR_INVALID_NETWORK; } if (mPrivileged) return SUCCESS; final int supported = KeepaliveUtils.getSupportedKeepalivesForNetworkCapabilities( mSupportedKeepalives, mNai.networkCapabilities); int takenUnprivilegedSlots = 0; for (final KeepaliveInfo ki : networkKeepalives.values()) { if (!ki.mPrivileged) ++takenUnprivilegedSlots; } if (takenUnprivilegedSlots > supported - mReservedPrivilegedSlots) { return ERROR_INSUFFICIENT_RESOURCES; } // Count unprivileged keepalives for the same uid across networks. int unprivilegedCountSameUid = 0; for (final HashMap kaForNetwork : mKeepalives.values()) { for (final KeepaliveInfo ki : kaForNetwork.values()) { if (ki.mUid == mUid) { unprivilegedCountSameUid++; } } } if (unprivilegedCountSameUid > mAllowedUnprivilegedSlotsForUid) { return ERROR_INSUFFICIENT_RESOURCES; } return SUCCESS; } private int checkLimit() { final HashMap networkKeepalives = mKeepalives.get(mNai); if (networkKeepalives == null) { return ERROR_INVALID_NETWORK; } final int supported = KeepaliveUtils.getSupportedKeepalivesForNetworkCapabilities( mSupportedKeepalives, mNai.networkCapabilities); if (supported == 0) return ERROR_UNSUPPORTED; if (networkKeepalives.size() > supported) return ERROR_INSUFFICIENT_RESOURCES; return SUCCESS; } private int isValid() { synchronized (mNai) { int error = checkInterval(); if (error == SUCCESS) error = checkLimit(); if (error == SUCCESS) error = checkPermission(); if (error == SUCCESS) error = checkNetworkConnected(); if (error == SUCCESS) error = checkSourceAddress(); return error; } } void start(int slot) { mSlot = slot; int error = isValid(); if (error == SUCCESS) { Log.d(TAG, "Starting keepalive " + mSlot + " on " + mNai.toShortString()); switch (mType) { case TYPE_NATT: mNai.asyncChannel.sendMessage( CMD_ADD_KEEPALIVE_PACKET_FILTER, slot, 0 /* Unused */, mPacket); mNai.asyncChannel .sendMessage(CMD_START_SOCKET_KEEPALIVE, slot, mInterval, mPacket); break; case TYPE_TCP: try { mTcpController.startSocketMonitor(mFd, this, mSlot); } catch (InvalidSocketException e) { handleStopKeepalive(mNai, mSlot, ERROR_INVALID_SOCKET); return; } mNai.asyncChannel.sendMessage( CMD_ADD_KEEPALIVE_PACKET_FILTER, slot, 0 /* Unused */, mPacket); // TODO: check result from apf and notify of failure as needed. mNai.asyncChannel .sendMessage(CMD_START_SOCKET_KEEPALIVE, slot, mInterval, mPacket); break; default: Log.wtf(TAG, "Starting keepalive with unknown type: " + mType); handleStopKeepalive(mNai, mSlot, error); return; } mStartedState = STARTING; } else { handleStopKeepalive(mNai, mSlot, error); return; } } void stop(int reason) { int uid = Binder.getCallingUid(); if (uid != mUid && uid != Process.SYSTEM_UID) { if (DBG) { Log.e(TAG, "Cannot stop unowned keepalive " + mSlot + " on " + mNai.network); } } Log.d(TAG, "Stopping keepalive " + mSlot + " on " + mNai.toShortString() + ": " + reason); switch (mStartedState) { case NOT_STARTED: // Remove the reference of the keepalive that meet error before starting, // e.g. invalid parameter. cleanupStoppedKeepalive(mNai, mSlot); break; case STOPPING: // Keepalive is already in stopping state, ignore. return; default: mStartedState = STOPPING; switch (mType) { case TYPE_TCP: mTcpController.stopSocketMonitor(mSlot); // fall through case TYPE_NATT: mNai.asyncChannel.sendMessage(CMD_STOP_SOCKET_KEEPALIVE, mSlot); mNai.asyncChannel.sendMessage(CMD_REMOVE_KEEPALIVE_PACKET_FILTER, mSlot); break; default: Log.wtf(TAG, "Stopping keepalive with unknown type: " + mType); } } // Close the duplicated fd that maintains the lifecycle of socket whenever // keepalive is running. if (mFd != null) { try { Os.close(mFd); } catch (ErrnoException e) { // This should not happen since system server controls the lifecycle of fd when // keepalive offload is running. Log.wtf(TAG, "Error closing fd for keepalive " + mSlot + ": " + e); } } if (reason == SUCCESS) { try { mCallback.onStopped(); } catch (RemoteException e) { Log.w(TAG, "Discarded onStop callback: " + reason); } } else if (reason == DATA_RECEIVED) { try { mCallback.onDataReceived(); } catch (RemoteException e) { Log.w(TAG, "Discarded onDataReceived callback: " + reason); } } else { notifyErrorCallback(mCallback, reason); } unlinkDeathRecipient(); } void onFileDescriptorInitiatedStop(final int socketKeepaliveReason) { handleStopKeepalive(mNai, mSlot, socketKeepaliveReason); } } void notifyErrorCallback(ISocketKeepaliveCallback cb, int error) { if (DBG) Log.w(TAG, "Sending onError(" + error + ") callback"); try { cb.onError(error); } catch (RemoteException e) { Log.w(TAG, "Discarded onError(" + error + ") callback"); } } private int findFirstFreeSlot(NetworkAgentInfo nai) { HashMap networkKeepalives = mKeepalives.get(nai); if (networkKeepalives == null) { networkKeepalives = new HashMap(); mKeepalives.put(nai, networkKeepalives); } // Find the lowest-numbered free slot. Slot numbers start from 1, because that's what two // separate chipset implementations independently came up with. int slot; for (slot = 1; slot <= networkKeepalives.size(); slot++) { if (networkKeepalives.get(slot) == null) { return slot; } } return slot; } public void handleStartKeepalive(Message message) { KeepaliveInfo ki = (KeepaliveInfo) message.obj; NetworkAgentInfo nai = ki.getNai(); int slot = findFirstFreeSlot(nai); mKeepalives.get(nai).put(slot, ki); ki.start(slot); } public void handleStopAllKeepalives(NetworkAgentInfo nai, int reason) { final HashMap networkKeepalives = mKeepalives.get(nai); if (networkKeepalives != null) { final ArrayList kalist = new ArrayList(networkKeepalives.values()); for (KeepaliveInfo ki : kalist) { ki.stop(reason); // Clean up keepalives since the network agent is disconnected and unable to pass // back asynchronous result of stop(). cleanupStoppedKeepalive(nai, ki.mSlot); } } } public void handleStopKeepalive(NetworkAgentInfo nai, int slot, int reason) { final String networkName = NetworkAgentInfo.toShortString(nai); HashMap networkKeepalives = mKeepalives.get(nai); if (networkKeepalives == null) { Log.e(TAG, "Attempt to stop keepalive on nonexistent network " + networkName); return; } KeepaliveInfo ki = networkKeepalives.get(slot); if (ki == null) { Log.e(TAG, "Attempt to stop nonexistent keepalive " + slot + " on " + networkName); return; } ki.stop(reason); // Clean up keepalives will be done as a result of calling ki.stop() after the slots are // freed. } private void cleanupStoppedKeepalive(NetworkAgentInfo nai, int slot) { final String networkName = NetworkAgentInfo.toShortString(nai); HashMap networkKeepalives = mKeepalives.get(nai); if (networkKeepalives == null) { Log.e(TAG, "Attempt to remove keepalive on nonexistent network " + networkName); return; } KeepaliveInfo ki = networkKeepalives.get(slot); if (ki == null) { Log.e(TAG, "Attempt to remove nonexistent keepalive " + slot + " on " + networkName); return; } networkKeepalives.remove(slot); Log.d(TAG, "Remove keepalive " + slot + " on " + networkName + ", " + networkKeepalives.size() + " remains."); if (networkKeepalives.isEmpty()) { mKeepalives.remove(nai); } } public void handleCheckKeepalivesStillValid(NetworkAgentInfo nai) { HashMap networkKeepalives = mKeepalives.get(nai); if (networkKeepalives != null) { ArrayList> invalidKeepalives = new ArrayList<>(); for (int slot : networkKeepalives.keySet()) { int error = networkKeepalives.get(slot).isValid(); if (error != SUCCESS) { invalidKeepalives.add(Pair.create(slot, error)); } } for (Pair slotAndError: invalidKeepalives) { handleStopKeepalive(nai, slotAndError.first, slotAndError.second); } } } /** Handle keepalive events from lower layer. */ public void handleEventSocketKeepalive(@NonNull NetworkAgentInfo nai, @NonNull Message message) { int slot = message.arg1; int reason = message.arg2; KeepaliveInfo ki = null; try { ki = mKeepalives.get(nai).get(slot); } catch(NullPointerException e) {} if (ki == null) { Log.e(TAG, "Event " + message.what + "," + slot + "," + reason + " for unknown keepalive " + slot + " on " + nai.toShortString()); return; } // This can be called in a number of situations : // - startedState is STARTING. // - reason is SUCCESS => go to STARTED. // - reason isn't SUCCESS => it's an error starting. Go to NOT_STARTED and stop keepalive. // - startedState is STARTED. // - reason is SUCCESS => it's a success stopping. Go to NOT_STARTED and stop keepalive. // - reason isn't SUCCESS => it's an error in exec. Go to NOT_STARTED and stop keepalive. // The control is not supposed to ever come here if the state is NOT_STARTED. This is // because in NOT_STARTED state, the code will switch to STARTING before sending messages // to start, and the only way to NOT_STARTED is this function, through the edges outlined // above : in all cases, keepalive gets stopped and can't restart without going into // STARTING as messages are ordered. This also depends on the hardware processing the // messages in order. // TODO : clarify this code and get rid of mStartedState. Using a StateMachine is an // option. if (KeepaliveInfo.STARTING == ki.mStartedState) { if (SUCCESS == reason) { // Keepalive successfully started. Log.d(TAG, "Started keepalive " + slot + " on " + nai.toShortString()); ki.mStartedState = KeepaliveInfo.STARTED; try { ki.mCallback.onStarted(slot); } catch (RemoteException e) { Log.w(TAG, "Discarded onStarted(" + slot + ") callback"); } } else { Log.d(TAG, "Failed to start keepalive " + slot + " on " + nai.toShortString() + ": " + reason); // The message indicated some error trying to start: do call handleStopKeepalive. handleStopKeepalive(nai, slot, reason); } } else if (KeepaliveInfo.STOPPING == ki.mStartedState) { // The message indicated result of stopping : clean up keepalive slots. Log.d(TAG, "Stopped keepalive " + slot + " on " + nai.toShortString() + " stopped: " + reason); ki.mStartedState = KeepaliveInfo.NOT_STARTED; cleanupStoppedKeepalive(nai, slot); } else { Log.wtf(TAG, "Event " + message.what + "," + slot + "," + reason + " for keepalive in wrong state: " + ki.toString()); } } /** * Called when requesting that keepalives be started on a IPsec NAT-T socket. See * {@link android.net.SocketKeepalive}. **/ public void startNattKeepalive(@Nullable NetworkAgentInfo nai, @Nullable FileDescriptor fd, int intervalSeconds, @NonNull ISocketKeepaliveCallback cb, @NonNull String srcAddrString, int srcPort, @NonNull String dstAddrString, int dstPort) { if (nai == null) { notifyErrorCallback(cb, ERROR_INVALID_NETWORK); return; } InetAddress srcAddress, dstAddress; try { srcAddress = NetworkUtils.numericToInetAddress(srcAddrString); dstAddress = NetworkUtils.numericToInetAddress(dstAddrString); } catch (IllegalArgumentException e) { notifyErrorCallback(cb, ERROR_INVALID_IP_ADDRESS); return; } KeepalivePacketData packet; try { packet = NattKeepalivePacketData.nattKeepalivePacket( srcAddress, srcPort, dstAddress, NATT_PORT); } catch (InvalidPacketException e) { notifyErrorCallback(cb, e.getError()); return; } KeepaliveInfo ki = null; try { ki = new KeepaliveInfo(cb, nai, packet, intervalSeconds, KeepaliveInfo.TYPE_NATT, fd); } catch (InvalidSocketException | IllegalArgumentException | SecurityException e) { Log.e(TAG, "Fail to construct keepalive", e); notifyErrorCallback(cb, ERROR_INVALID_SOCKET); return; } Log.d(TAG, "Created keepalive: " + ki.toString()); mConnectivityServiceHandler.obtainMessage( NetworkAgent.CMD_START_SOCKET_KEEPALIVE, ki).sendToTarget(); } /** * Called by ConnectivityService to start TCP keepalive on a file descriptor. * * In order to offload keepalive for application correctly, sequence number, ack number and * other fields are needed to form the keepalive packet. Thus, this function synchronously * puts the socket into repair mode to get the necessary information. After the socket has been * put into repair mode, the application cannot access the socket until reverted to normal. * * See {@link android.net.SocketKeepalive}. **/ public void startTcpKeepalive(@Nullable NetworkAgentInfo nai, @NonNull FileDescriptor fd, int intervalSeconds, @NonNull ISocketKeepaliveCallback cb) { if (nai == null) { notifyErrorCallback(cb, ERROR_INVALID_NETWORK); return; } final TcpKeepalivePacketData packet; try { packet = TcpKeepaliveController.getTcpKeepalivePacket(fd); } catch (InvalidSocketException e) { notifyErrorCallback(cb, e.error); return; } catch (InvalidPacketException e) { notifyErrorCallback(cb, e.getError()); return; } KeepaliveInfo ki = null; try { ki = new KeepaliveInfo(cb, nai, packet, intervalSeconds, KeepaliveInfo.TYPE_TCP, fd); } catch (InvalidSocketException | IllegalArgumentException | SecurityException e) { Log.e(TAG, "Fail to construct keepalive e=" + e); notifyErrorCallback(cb, ERROR_INVALID_SOCKET); return; } Log.d(TAG, "Created keepalive: " + ki.toString()); mConnectivityServiceHandler.obtainMessage(CMD_START_SOCKET_KEEPALIVE, ki).sendToTarget(); } /** * Called when requesting that keepalives be started on a IPsec NAT-T socket. This function is * identical to {@link #startNattKeepalive}, but also takes a {@code resourceId}, which is the * resource index bound to the {@link UdpEncapsulationSocket} when creating by * {@link com.android.server.IpSecService} to verify whether the given * {@link UdpEncapsulationSocket} is legitimate. **/ public void startNattKeepalive(@Nullable NetworkAgentInfo nai, @Nullable FileDescriptor fd, int resourceId, int intervalSeconds, @NonNull ISocketKeepaliveCallback cb, @NonNull String srcAddrString, @NonNull String dstAddrString, int dstPort) { // Ensure that the socket is created by IpSecService. if (!isNattKeepaliveSocketValid(fd, resourceId)) { notifyErrorCallback(cb, ERROR_INVALID_SOCKET); } // Get src port to adopt old API. int srcPort = 0; try { final SocketAddress srcSockAddr = Os.getsockname(fd); srcPort = ((InetSocketAddress) srcSockAddr).getPort(); } catch (ErrnoException e) { notifyErrorCallback(cb, ERROR_INVALID_SOCKET); } // Forward request to old API. startNattKeepalive(nai, fd, intervalSeconds, cb, srcAddrString, srcPort, dstAddrString, dstPort); } /** * Verify if the IPsec NAT-T file descriptor and resource Id hold for IPsec keepalive is valid. **/ public static boolean isNattKeepaliveSocketValid(@Nullable FileDescriptor fd, int resourceId) { // TODO: 1. confirm whether the fd is called from system api or created by IpSecService. // 2. If the fd is created from the system api, check that it's bounded. And // call dup to keep the fd open. // 3. If the fd is created from IpSecService, check if the resource ID is valid. And // hold the resource needed in IpSecService. if (null == fd) { return false; } return true; } public void dump(IndentingPrintWriter pw) { pw.println("Supported Socket keepalives: " + Arrays.toString(mSupportedKeepalives)); pw.println("Reserved Privileged keepalives: " + mReservedPrivilegedSlots); pw.println("Allowed Unprivileged keepalives per uid: " + mAllowedUnprivilegedSlotsForUid); pw.println("Socket keepalives:"); pw.increaseIndent(); for (NetworkAgentInfo nai : mKeepalives.keySet()) { pw.println(nai.toShortString()); pw.increaseIndent(); for (int slot : mKeepalives.get(nai).keySet()) { KeepaliveInfo ki = mKeepalives.get(nai).get(slot); pw.println(slot + ": " + ki.toString()); } pw.decreaseIndent(); } pw.decreaseIndent(); } }