SoftApManager.java revision f502d3e20409d81cfefd762b3b44f46dead09a92 
1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.server.wifi;
18
19import static com.android.server.wifi.util.ApConfigUtil.ERROR_GENERIC;
20import static com.android.server.wifi.util.ApConfigUtil.ERROR_NO_CHANNEL;
21import static com.android.server.wifi.util.ApConfigUtil.SUCCESS;
22
23import android.content.Context;
24import android.net.ConnectivityManager;
25import android.net.wifi.WifiConfiguration;
26import android.net.wifi.WifiManager;
27import android.os.INetworkManagementService;
28import android.os.Looper;
29import android.os.Message;
30import android.util.Log;
31
32import com.android.internal.util.State;
33import com.android.internal.util.StateMachine;
34import com.android.server.wifi.util.ApConfigUtil;
35
36import java.util.ArrayList;
37import java.util.Locale;
38
39/**
40 * Manage WiFi in AP mode.
41 * The internal state machine runs under "WifiStateMachine" thread context.
42 */
43public class SoftApManager {
44    private static final String TAG = "SoftApManager";
45
46    private final INetworkManagementService mNmService;
47    private final WifiNative mWifiNative;
48    private final ArrayList<Integer> mAllowed2GChannels;
49
50    private final String mCountryCode;
51
52    private final String mInterfaceName;
53
54    private final SoftApStateMachine mStateMachine;
55
56    private final Listener mListener;
57
58    /**
59     * Listener for soft AP state changes.
60     */
61    public interface Listener {
62        /**
63         * Invoke when AP state changed.
64         * @param state new AP state
65         * @param failureReason reason when in failed state
66         */
67        void onStateChanged(int state, int failureReason);
68    }
69
70    public SoftApManager(Looper looper,
71                         WifiNative wifiNative,
72                         INetworkManagementService nmService,
73                         String countryCode,
74                         ArrayList<Integer> allowed2GChannels,
75                         Listener listener) {
76        mStateMachine = new SoftApStateMachine(looper);
77
78        mNmService = nmService;
79        mWifiNative = wifiNative;
80        mCountryCode = countryCode;
81        mAllowed2GChannels = allowed2GChannels;
82        mListener = listener;
83
84        mInterfaceName = mWifiNative.getInterfaceName();
85    }
86
87    /**
88     * Start soft AP with given configuration.
89     * @param config AP configuration
90     */
91    public void start(WifiConfiguration config) {
92        mStateMachine.sendMessage(SoftApStateMachine.CMD_START, config);
93    }
94
95    /**
96     * Stop soft AP.
97     */
98    public void stop() {
99        mStateMachine.sendMessage(SoftApStateMachine.CMD_STOP);
100    }
101
102    /**
103     * Update AP state.
104     * @param state new AP state
105     * @param reason Failure reason if the new AP state is in failure state
106     */
107    private void updateApState(int state, int reason) {
108        if (mListener != null) {
109            mListener.onStateChanged(state, reason);
110        }
111    }
112
113    /**
114     * Start a soft AP instance with the given configuration.
115     * @param config AP configuration
116     * @return integer result code
117     */
118    private int startSoftAp(WifiConfiguration config) {
119        if (config == null) {
120            Log.e(TAG, "Unable to start soft AP without configuration");
121            return ERROR_GENERIC;
122        }
123
124        /* Make a copy of configuration for updating AP band and channel. */
125        WifiConfiguration localConfig = new WifiConfiguration(config);
126
127        int result = ApConfigUtil.updateApChannelConfig(
128                mWifiNative, mCountryCode, mAllowed2GChannels, localConfig);
129        if (result != SUCCESS) {
130            Log.e(TAG, "Failed to update AP band and channel");
131            return result;
132        }
133
134        /* Setup country code if it is provide. */
135        if (mCountryCode != null) {
136            /**
137             * Country code is mandatory for 5GHz band, return an error if failed to set
138             * country code when AP is configured for 5GHz band.
139             */
140            if (!mWifiNative.setCountryCodeHal(mCountryCode.toUpperCase(Locale.ROOT))
141                    && config.apBand == WifiConfiguration.AP_BAND_5GHZ) {
142                Log.e(TAG, "Failed to set country code, required for setting up "
143                        + "soft ap in 5GHz");
144                return ERROR_GENERIC;
145            }
146        }
147
148        try {
149            mNmService.startAccessPoint(localConfig, mInterfaceName);
150        } catch (Exception e) {
151            Log.e(TAG, "Exception in starting soft AP: " + e);
152            return ERROR_GENERIC;
153        }
154
155        Log.d(TAG, "Soft AP is started");
156
157        return SUCCESS;
158    }
159
160    /**
161     * Teardown soft AP.
162     */
163    private void stopSoftAp() {
164        try {
165            mNmService.stopAccessPoint(mInterfaceName);
166        } catch (Exception e) {
167            Log.e(TAG, "Exception in stopping soft AP: " + e);
168            return;
169        }
170        Log.d(TAG, "Soft AP is stopped");
171    }
172
173    private class SoftApStateMachine extends StateMachine {
174        /* Commands for the state machine. */
175        public static final int CMD_START = 0;
176        public static final int CMD_STOP = 1;
177
178        private final State mIdleState = new IdleState();
179        private final State mStartedState = new StartedState();
180
181        SoftApStateMachine(Looper looper) {
182            super(TAG, looper);
183
184            addState(mIdleState);
185            addState(mStartedState, mIdleState);
186
187            setInitialState(mIdleState);
188            start();
189        }
190
191        private class IdleState extends State {
192            @Override
193            public boolean processMessage(Message message) {
194                switch (message.what) {
195                    case CMD_START:
196                        updateApState(WifiManager.WIFI_AP_STATE_ENABLING, 0);
197                        int result = startSoftAp((WifiConfiguration) message.obj);
198                        if (result == SUCCESS) {
199                            updateApState(WifiManager.WIFI_AP_STATE_ENABLED, 0);
200                            transitionTo(mStartedState);
201                        } else {
202                            int reason = WifiManager.SAP_START_FAILURE_GENERAL;
203                            if (result == ERROR_NO_CHANNEL) {
204                                reason = WifiManager.SAP_START_FAILURE_NO_CHANNEL;
205                            }
206                            updateApState(WifiManager.WIFI_AP_STATE_FAILED, reason);
207                        }
208                        break;
209                    default:
210                        /* Ignore all other commands. */
211                        break;
212                }
213                return HANDLED;
214            }
215        }
216
217        private class StartedState extends State {
218            @Override
219            public boolean processMessage(Message message) {
220                switch (message.what) {
221                    case CMD_START:
222                        /* Already started, ignore this command. */
223                        break;
224                    case CMD_STOP:
225                        updateApState(WifiManager.WIFI_AP_STATE_DISABLING, 0);
226                        stopSoftAp();
227                        updateApState(WifiManager.WIFI_AP_STATE_DISABLED, 0);
228                        transitionTo(mIdleState);
229                        break;
230                    default:
231                        return NOT_HANDLED;
232                }
233                return HANDLED;
234            }
235        }
236
237    }
238}
239