1/*
2 * Copyright (C) 2011 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 android.net;
18
19import static android.content.pm.PackageManager.GET_SIGNATURES;
20import static android.net.NetworkPolicy.CYCLE_NONE;
21import static android.text.format.Time.MONTH_DAY;
22
23import android.content.Context;
24import android.content.Intent;
25import android.content.pm.PackageManager;
26import android.content.pm.PackageManager.NameNotFoundException;
27import android.content.pm.Signature;
28import android.os.RemoteException;
29import android.os.UserHandle;
30import android.text.format.Time;
31
32import com.google.android.collect.Sets;
33
34import java.io.PrintWriter;
35import java.util.HashSet;
36
37/**
38 * Manager for creating and modifying network policy rules.
39 *
40 * {@hide}
41 */
42public class NetworkPolicyManager {
43
44    /* POLICY_* are masks and can be ORed */
45    /** No specific network policy, use system default. */
46    public static final int POLICY_NONE = 0x0;
47    /** Reject network usage on metered networks when application in background. */
48    public static final int POLICY_REJECT_METERED_BACKGROUND = 0x1;
49    /** Allow network use (metered or not) in the background in battery save mode. */
50    public static final int POLICY_ALLOW_BACKGROUND_BATTERY_SAVE = 0x2;
51
52    /* RULE_* are not masks and they must be exclusive */
53    /** All network traffic should be allowed. */
54    public static final int RULE_ALLOW_ALL = 0x0;
55    /** Reject traffic on metered networks. */
56    public static final int RULE_REJECT_METERED = 0x1;
57    /** Reject traffic on all networks. */
58    public static final int RULE_REJECT_ALL = 0x2;
59
60    public static final int FIREWALL_RULE_DEFAULT = 0;
61    public static final int FIREWALL_RULE_ALLOW = 1;
62    public static final int FIREWALL_RULE_DENY = 2;
63
64    public static final int FIREWALL_TYPE_WHITELIST = 0;
65    public static final int FIREWALL_TYPE_BLACKLIST = 1;
66
67    public static final int FIREWALL_CHAIN_NONE = 0;
68    public static final int FIREWALL_CHAIN_DOZABLE = 1;
69    public static final int FIREWALL_CHAIN_STANDBY = 2;
70
71    public static final String FIREWALL_CHAIN_NAME_NONE = "none";
72    public static final String FIREWALL_CHAIN_NAME_DOZABLE = "dozable";
73    public static final String FIREWALL_CHAIN_NAME_STANDBY = "standby";
74
75    private static final boolean ALLOW_PLATFORM_APP_POLICY = true;
76
77    /**
78     * {@link Intent} extra that indicates which {@link NetworkTemplate} rule it
79     * applies to.
80     */
81    public static final String EXTRA_NETWORK_TEMPLATE = "android.net.NETWORK_TEMPLATE";
82
83    private final Context mContext;
84    private INetworkPolicyManager mService;
85
86    public NetworkPolicyManager(Context context, INetworkPolicyManager service) {
87        if (service == null) {
88            throw new IllegalArgumentException("missing INetworkPolicyManager");
89        }
90        mContext = context;
91        mService = service;
92    }
93
94    public static NetworkPolicyManager from(Context context) {
95        return (NetworkPolicyManager) context.getSystemService(Context.NETWORK_POLICY_SERVICE);
96    }
97
98    /**
99     * Set policy flags for specific UID.
100     *
101     * @param policy {@link #POLICY_NONE} or combination of flags like
102     * {@link #POLICY_REJECT_METERED_BACKGROUND} or {@link #POLICY_ALLOW_BACKGROUND_BATTERY_SAVE}.
103     */
104    public void setUidPolicy(int uid, int policy) {
105        try {
106            mService.setUidPolicy(uid, policy);
107        } catch (RemoteException e) {
108        }
109    }
110
111    /**
112     * Add policy flags for specific UID.  The given policy bits will be set for
113     * the uid.  Policy flags may be either
114     * {@link #POLICY_REJECT_METERED_BACKGROUND} or {@link #POLICY_ALLOW_BACKGROUND_BATTERY_SAVE}.
115     */
116    public void addUidPolicy(int uid, int policy) {
117        try {
118            mService.addUidPolicy(uid, policy);
119        } catch (RemoteException e) {
120        }
121    }
122
123    /**
124     * Clear/remove policy flags for specific UID.  The given policy bits will be set for
125     * the uid.  Policy flags may be either
126     * {@link #POLICY_REJECT_METERED_BACKGROUND} or {@link #POLICY_ALLOW_BACKGROUND_BATTERY_SAVE}.
127     */
128    public void removeUidPolicy(int uid, int policy) {
129        try {
130            mService.removeUidPolicy(uid, policy);
131        } catch (RemoteException e) {
132        }
133    }
134
135    public int getUidPolicy(int uid) {
136        try {
137            return mService.getUidPolicy(uid);
138        } catch (RemoteException e) {
139            return POLICY_NONE;
140        }
141    }
142
143    public int[] getUidsWithPolicy(int policy) {
144        try {
145            return mService.getUidsWithPolicy(policy);
146        } catch (RemoteException e) {
147            return new int[0];
148        }
149    }
150
151    public void registerListener(INetworkPolicyListener listener) {
152        try {
153            mService.registerListener(listener);
154        } catch (RemoteException e) {
155        }
156    }
157
158    public void unregisterListener(INetworkPolicyListener listener) {
159        try {
160            mService.unregisterListener(listener);
161        } catch (RemoteException e) {
162        }
163    }
164
165    public void setNetworkPolicies(NetworkPolicy[] policies) {
166        try {
167            mService.setNetworkPolicies(policies);
168        } catch (RemoteException e) {
169        }
170    }
171
172    public NetworkPolicy[] getNetworkPolicies() {
173        try {
174            return mService.getNetworkPolicies(mContext.getOpPackageName());
175        } catch (RemoteException e) {
176            return null;
177        }
178    }
179
180    public void setRestrictBackground(boolean restrictBackground) {
181        try {
182            mService.setRestrictBackground(restrictBackground);
183        } catch (RemoteException e) {
184        }
185    }
186
187    public boolean getRestrictBackground() {
188        try {
189            return mService.getRestrictBackground();
190        } catch (RemoteException e) {
191            return false;
192        }
193    }
194
195    /**
196     * Resets network policy settings back to factory defaults.
197     *
198     * @hide
199     */
200    public void factoryReset(String subscriber) {
201        try {
202            mService.factoryReset(subscriber);
203        } catch (RemoteException e) {
204        }
205    }
206
207    /**
208     * Compute the last cycle boundary for the given {@link NetworkPolicy}. For
209     * example, if cycle day is 20th, and today is June 15th, it will return May
210     * 20th. When cycle day doesn't exist in current month, it snaps to the 1st
211     * of following month.
212     *
213     * @hide
214     */
215    public static long computeLastCycleBoundary(long currentTime, NetworkPolicy policy) {
216        if (policy.cycleDay == CYCLE_NONE) {
217            throw new IllegalArgumentException("Unable to compute boundary without cycleDay");
218        }
219
220        final Time now = new Time(policy.cycleTimezone);
221        now.set(currentTime);
222
223        // first, find cycle boundary for current month
224        final Time cycle = new Time(now);
225        cycle.hour = cycle.minute = cycle.second = 0;
226        snapToCycleDay(cycle, policy.cycleDay);
227
228        if (Time.compare(cycle, now) >= 0) {
229            // cycle boundary is beyond now, use last cycle boundary; start by
230            // pushing ourselves squarely into last month.
231            final Time lastMonth = new Time(now);
232            lastMonth.hour = lastMonth.minute = lastMonth.second = 0;
233            lastMonth.monthDay = 1;
234            lastMonth.month -= 1;
235            lastMonth.normalize(true);
236
237            cycle.set(lastMonth);
238            snapToCycleDay(cycle, policy.cycleDay);
239        }
240
241        return cycle.toMillis(true);
242    }
243
244    /** {@hide} */
245    public static long computeNextCycleBoundary(long currentTime, NetworkPolicy policy) {
246        if (policy.cycleDay == CYCLE_NONE) {
247            throw new IllegalArgumentException("Unable to compute boundary without cycleDay");
248        }
249
250        final Time now = new Time(policy.cycleTimezone);
251        now.set(currentTime);
252
253        // first, find cycle boundary for current month
254        final Time cycle = new Time(now);
255        cycle.hour = cycle.minute = cycle.second = 0;
256        snapToCycleDay(cycle, policy.cycleDay);
257
258        if (Time.compare(cycle, now) <= 0) {
259            // cycle boundary is before now, use next cycle boundary; start by
260            // pushing ourselves squarely into next month.
261            final Time nextMonth = new Time(now);
262            nextMonth.hour = nextMonth.minute = nextMonth.second = 0;
263            nextMonth.monthDay = 1;
264            nextMonth.month += 1;
265            nextMonth.normalize(true);
266
267            cycle.set(nextMonth);
268            snapToCycleDay(cycle, policy.cycleDay);
269        }
270
271        return cycle.toMillis(true);
272    }
273
274    /**
275     * Snap to the cycle day for the current month given; when cycle day doesn't
276     * exist, it snaps to last second of current month.
277     *
278     * @hide
279     */
280    public static void snapToCycleDay(Time time, int cycleDay) {
281        if (cycleDay > time.getActualMaximum(MONTH_DAY)) {
282            // cycle day isn't valid this month; snap to last second of month
283            time.month += 1;
284            time.monthDay = 1;
285            time.second = -1;
286        } else {
287            time.monthDay = cycleDay;
288        }
289        time.normalize(true);
290    }
291
292    /**
293     * Check if given UID can have a {@link #setUidPolicy(int, int)} defined,
294     * usually to protect critical system services.
295     */
296    @Deprecated
297    public static boolean isUidValidForPolicy(Context context, int uid) {
298        // first, quick-reject non-applications
299        if (!UserHandle.isApp(uid)) {
300            return false;
301        }
302
303        if (!ALLOW_PLATFORM_APP_POLICY) {
304            final PackageManager pm = context.getPackageManager();
305            final HashSet<Signature> systemSignature;
306            try {
307                systemSignature = Sets.newHashSet(
308                        pm.getPackageInfo("android", GET_SIGNATURES).signatures);
309            } catch (NameNotFoundException e) {
310                throw new RuntimeException("problem finding system signature", e);
311            }
312
313            try {
314                // reject apps signed with platform cert
315                for (String packageName : pm.getPackagesForUid(uid)) {
316                    final HashSet<Signature> packageSignature = Sets.newHashSet(
317                            pm.getPackageInfo(packageName, GET_SIGNATURES).signatures);
318                    if (packageSignature.containsAll(systemSignature)) {
319                        return false;
320                    }
321                }
322            } catch (NameNotFoundException e) {
323            }
324        }
325
326        // nothing found above; we can apply policy to UID
327        return true;
328    }
329
330    /** {@hide} */
331    public static void dumpPolicy(PrintWriter fout, int policy) {
332        fout.write("[");
333        if ((policy & POLICY_REJECT_METERED_BACKGROUND) != 0) {
334            fout.write("REJECT_METERED_BACKGROUND");
335        }
336        fout.write("]");
337    }
338
339    /** {@hide} */
340    public static void dumpRules(PrintWriter fout, int rules) {
341        fout.write("[");
342        if ((rules & RULE_REJECT_METERED) != 0) {
343            fout.write("REJECT_METERED");
344        } else if ((rules & RULE_REJECT_ALL) != 0) {
345            fout.write("REJECT_ALL");
346        }
347        fout.write("]");
348    }
349
350}
351