1 /*
2  * Copyright (C) 2012 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 
17 package android.telephony;
18 
19 import android.annotation.IntDef;
20 import android.annotation.NonNull;
21 import android.annotation.Nullable;
22 import android.annotation.SystemApi;
23 import android.os.Parcel;
24 import android.os.Parcelable;
25 
26 import com.android.internal.telephony.uicc.IccUtils;
27 
28 import java.lang.annotation.Retention;
29 import java.lang.annotation.RetentionPolicy;
30 import java.time.DateTimeException;
31 import java.time.LocalDateTime;
32 import java.time.ZoneOffset;
33 import java.util.Arrays;
34 
35 /**
36  * Contains information elements for a GSM or UMTS ETWS (Earthquake and Tsunami Warning
37  * System) warning notification. Supported values for each element are defined in 3GPP TS 23.041.
38  *
39  * {@hide}
40  */
41 @SystemApi
42 public final class SmsCbEtwsInfo implements Parcelable {
43 
44     /** ETWS warning type for earthquake. */
45     public static final int ETWS_WARNING_TYPE_EARTHQUAKE = 0x00;
46 
47     /** ETWS warning type for tsunami. */
48     public static final int ETWS_WARNING_TYPE_TSUNAMI = 0x01;
49 
50     /** ETWS warning type for earthquake and tsunami. */
51     public static final int ETWS_WARNING_TYPE_EARTHQUAKE_AND_TSUNAMI = 0x02;
52 
53     /** ETWS warning type for test messages. */
54     public static final int ETWS_WARNING_TYPE_TEST_MESSAGE = 0x03;
55 
56     /** ETWS warning type for other emergency types. */
57     public static final int ETWS_WARNING_TYPE_OTHER_EMERGENCY = 0x04;
58 
59     /** Unknown ETWS warning type. */
60     public static final int ETWS_WARNING_TYPE_UNKNOWN = -1;
61 
62     /** @hide */
63     @Retention(RetentionPolicy.SOURCE)
64     @IntDef(prefix = {"ETWS_WARNING_TYPE_"},
65             value = {
66                     ETWS_WARNING_TYPE_EARTHQUAKE,
67                     ETWS_WARNING_TYPE_TSUNAMI,
68                     ETWS_WARNING_TYPE_EARTHQUAKE_AND_TSUNAMI,
69                     ETWS_WARNING_TYPE_TEST_MESSAGE,
70                     ETWS_WARNING_TYPE_OTHER_EMERGENCY,
71                     ETWS_WARNING_TYPE_UNKNOWN,
72             })
73     public @interface WarningType {}
74 
75     /** One of the ETWS warning type constants defined in this class. */
76     private final @WarningType int mWarningType;
77 
78     /** Whether or not to activate the emergency user alert tone and vibration. */
79     private final boolean mIsEmergencyUserAlert;
80 
81     /** Whether or not to activate a popup alert. */
82     private final boolean mIsPopupAlert;
83 
84     /** Whether ETWS primary message or not/ */
85     private final boolean mIsPrimary;
86 
87     /**
88      * 50-byte security information (ETWS primary notification for GSM only). As of Release 10,
89      * 3GPP TS 23.041 states that the UE shall ignore the ETWS primary notification timestamp
90      * and digital signature if received. Therefore it is treated as a raw byte array and
91      * parceled with the broadcast intent if present, but the timestamp is only computed if an
92      * application asks for the individual components.
93      */
94     @Nullable
95     private final byte[] mWarningSecurityInformation;
96 
97     /**
98      * Create a new SmsCbEtwsInfo object with the specified values.
99      * @param warningType the type of ETWS warning
100      * @param isEmergencyUserAlert whether the warning is an emergency alert, which will activate
101      *                             the user alert tone and vibration
102      * @param isPopupAlert whether the warning will activate a popup alert
103      * @param isPrimary whether this is an ETWS primary message
104      * @param warningSecurityInformation 50-byte security information (for primary notifications
105      *                                   on GSM only).
106      */
SmsCbEtwsInfo(@arningType int warningType, boolean isEmergencyUserAlert, boolean isPopupAlert, boolean isPrimary, @Nullable byte[] warningSecurityInformation)107     public SmsCbEtwsInfo(@WarningType int warningType, boolean isEmergencyUserAlert,
108             boolean isPopupAlert,
109             boolean isPrimary, @Nullable byte[] warningSecurityInformation) {
110         mWarningType = warningType;
111         mIsEmergencyUserAlert = isEmergencyUserAlert;
112         mIsPopupAlert = isPopupAlert;
113         mIsPrimary = isPrimary;
114         mWarningSecurityInformation = warningSecurityInformation;
115     }
116 
117     /** Create a new SmsCbEtwsInfo object from a Parcel. */
SmsCbEtwsInfo(Parcel in)118     SmsCbEtwsInfo(Parcel in) {
119         mWarningType = in.readInt();
120         mIsEmergencyUserAlert = (in.readInt() != 0);
121         mIsPopupAlert = (in.readInt() != 0);
122         mIsPrimary = (in.readInt() != 0);
123         mWarningSecurityInformation = in.createByteArray();
124     }
125 
126     /**
127      * Flatten this object into a Parcel.
128      *
129      * @param dest  The Parcel in which the object should be written.
130      * @param flags Additional flags about how the object should be written (ignored).
131      */
132     @Override
writeToParcel(Parcel dest, int flags)133     public void writeToParcel(Parcel dest, int flags) {
134         dest.writeInt(mWarningType);
135         dest.writeInt(mIsEmergencyUserAlert ? 1 : 0);
136         dest.writeInt(mIsPopupAlert ? 1 : 0);
137         dest.writeInt(mIsPrimary ? 1 : 0);
138         dest.writeByteArray(mWarningSecurityInformation);
139     }
140 
141     /**
142      * Returns the ETWS warning type.
143      * @return a warning type such as {@link #ETWS_WARNING_TYPE_EARTHQUAKE}
144      */
getWarningType()145     public @WarningType int getWarningType() {
146         return mWarningType;
147     }
148 
149     /**
150      * Returns the ETWS emergency user alert flag. If the ETWS message is an emergency alert, it
151      * will activate an alert tone and vibration.
152      * @return true to notify terminal to activate emergency user alert; false otherwise
153      */
isEmergencyUserAlert()154     public boolean isEmergencyUserAlert() {
155         return mIsEmergencyUserAlert;
156     }
157 
158     /**
159      * Returns the ETWS activate popup flag.
160      * @return true to notify terminal to activate display popup; false otherwise
161      */
isPopupAlert()162     public boolean isPopupAlert() {
163         return mIsPopupAlert;
164     }
165 
166     /**
167      * Returns the ETWS format flag.
168      * @return true if the message is primary message, otherwise secondary message
169      */
isPrimary()170     public boolean isPrimary() {
171         return mIsPrimary;
172     }
173 
174     /**
175      * Returns the Warning-Security-Information timestamp (GSM primary notifications only).
176      * As of Release 10, 3GPP TS 23.041 states that the UE shall ignore this value if received.
177      * @return a UTC timestamp in System.currentTimeMillis() format, or 0 if not present or invalid.
178      */
getPrimaryNotificationTimestamp()179     public long getPrimaryNotificationTimestamp() {
180         if (mWarningSecurityInformation == null || mWarningSecurityInformation.length < 7) {
181             return 0;
182         }
183 
184         int year = IccUtils.gsmBcdByteToInt(mWarningSecurityInformation[0]);
185         int month = IccUtils.gsmBcdByteToInt(mWarningSecurityInformation[1]);
186         int day = IccUtils.gsmBcdByteToInt(mWarningSecurityInformation[2]);
187         int hour = IccUtils.gsmBcdByteToInt(mWarningSecurityInformation[3]);
188         int minute = IccUtils.gsmBcdByteToInt(mWarningSecurityInformation[4]);
189         int second = IccUtils.gsmBcdByteToInt(mWarningSecurityInformation[5]);
190 
191         // For the timezone, the most significant bit of the
192         // least significant nibble is the sign byte
193         // (meaning the max range of this field is 79 quarter-hours,
194         // which is more than enough)
195 
196         byte tzByte = mWarningSecurityInformation[6];
197 
198         // Mask out sign bit.
199         int timezoneOffset = IccUtils.gsmBcdByteToInt((byte) (tzByte & (~0x08)));
200 
201         timezoneOffset = ((tzByte & 0x08) == 0) ? timezoneOffset : -timezoneOffset;
202         // timezoneOffset is in quarter hours.
203         int timeZoneOffsetSeconds = timezoneOffset * 15 * 60;
204 
205         try {
206             LocalDateTime localDateTime = LocalDateTime.of(
207                     // We only need to support years above 2000.
208                     year + 2000,
209                     month /* 1-12 */,
210                     day,
211                     hour,
212                     minute,
213                     second);
214 
215             long epochSeconds = localDateTime.toEpochSecond(ZoneOffset.UTC) - timeZoneOffsetSeconds;
216             // Convert to milliseconds, ignore overflow.
217             return epochSeconds * 1000;
218         } catch (DateTimeException ex) {
219             // No-op
220         }
221         return 0;
222     }
223 
224     /**
225      * Returns the digital signature (GSM primary notifications only). As of Release 10,
226      * 3GPP TS 23.041 states that the UE shall ignore this value if received.
227      * @return a byte array containing a copy of the primary notification digital signature
228      */
229     @Nullable
getPrimaryNotificationSignature()230     public byte[] getPrimaryNotificationSignature() {
231         if (mWarningSecurityInformation == null || mWarningSecurityInformation.length < 50) {
232             return null;
233         }
234         return Arrays.copyOfRange(mWarningSecurityInformation, 7, 50);
235     }
236 
237     @Override
toString()238     public String toString() {
239         return "SmsCbEtwsInfo{warningType=" + mWarningType + ", emergencyUserAlert="
240                 + mIsEmergencyUserAlert + ", activatePopup=" + mIsPopupAlert + '}';
241     }
242 
243     /**
244      * Describe the kinds of special objects contained in the marshalled representation.
245      * @return a bitmask indicating this Parcelable contains no special objects
246      */
247     @Override
describeContents()248     public int describeContents() {
249         return 0;
250     }
251 
252     /** Creator for unparcelling objects. */
253     @NonNull
254     public static final Creator<SmsCbEtwsInfo> CREATOR = new Creator<SmsCbEtwsInfo>() {
255         @Override
256         public SmsCbEtwsInfo createFromParcel(Parcel in) {
257             return new SmsCbEtwsInfo(in);
258         }
259 
260         @Override
261         public SmsCbEtwsInfo[] newArray(int size) {
262             return new SmsCbEtwsInfo[size];
263         }
264     };
265 }
266