Fixes for SMS Cell Broadcast support.

Add support for ETWS primary notification messages.
Add method for easy concatenation of GSM multi-part broadcasts.
Add test cases for SmsCbHeader, SmsCbMessage and IntRangeManager.

Change-Id: Ifc646a011e79ad6c7eace9afcf84b1216eb42b7a

2 files changed, 133 insertions, 13 deletions

diff --git a/telephony/java/android/telephony/SmsCbConstants.java b/telephony/java/android/telephony/SmsCbConstants.java
index 1ac9ae3..a1b4adf 100644
--- a/telephony/java/android/telephony/SmsCbConstants.java
+++ b/telephony/java/android/telephony/SmsCbConstants.java
@@ -22,18 +22,6 @@ package android.telephony;
  * {@hide}
  */
 public interface SmsCbConstants {
-    /** Cell wide immediate geographical scope */
-    public static final int GEOGRAPHICAL_SCOPE_CELL_WIDE_IMMEDIATE = 0;
-
-    /** PLMN wide geographical scope */
-    public static final int GEOGRAPHICAL_SCOPE_PLMN_WIDE = 1;
-
-    /** Location / service area wide geographical scope */
-    public static final int GEOGRAPHICAL_SCOPE_LA_WIDE = 2;
-
-    /** Cell wide geographical scope */
-    public static final int GEOGRAPHICAL_SCOPE_CELL_WIDE = 3;
-
     /** Start of PWS Message Identifier range (includes ETWS and CMAS). */
     public static final int MESSAGE_ID_PWS_FIRST_IDENTIFIER = 0x1100;
 
@@ -111,4 +99,19 @@ public interface SmsCbConstants {
 
     /** ETWS message code flag to activate the emergency user alert. */
     public static final int MESSAGE_CODE_ETWS_EMERGENCY_USER_ALERT          = 0x200;
+
+    /** ETWS warning type value for earthquake. */
+    public static final int ETWS_WARNING_TYPE_EARTHQUAKE                    = 0x00;
+
+    /** ETWS warning type value for tsunami. */
+    public static final int ETWS_WARNING_TYPE_TSUNAMI                       = 0x01;
+
+    /** ETWS warning type value for earthquake and tsunami. */
+    public static final int ETWS_WARNING_TYPE_EARTHQUAKE_AND_TSUNAMI        = 0x02;
+
+    /** ETWS warning type value for test broadcast. */
+    public static final int ETWS_WARNING_TYPE_TEST                          = 0x03;
+
+    /** ETWS warning type value for other notifications. */
+    public static final int ETWS_WARNING_TYPE_OTHER                         = 0x04;
 }
diff --git a/telephony/java/android/telephony/SmsCbMessage.java b/telephony/java/android/telephony/SmsCbMessage.java
index 6da48d6..383e0f9 100644
--- a/telephony/java/android/telephony/SmsCbMessage.java
+++ b/telephony/java/android/telephony/SmsCbMessage.java
@@ -16,9 +16,11 @@
 
 package android.telephony;
 
+import android.text.format.Time;
 import android.util.Log;
 
 import com.android.internal.telephony.GsmAlphabet;
+import com.android.internal.telephony.IccUtils;
 import com.android.internal.telephony.gsm.SmsCbHeader;
 
 import java.io.UnsupportedEncodingException;
@@ -93,9 +95,26 @@ public class SmsCbMessage {
 
     private String mBody;
 
+    /** Timestamp of ETWS primary notification with security. */
+    private long mPrimaryNotificationTimestamp;
+
+    /** 43 byte digital signature of ETWS primary notification with security. */
+    private byte[] mPrimaryNotificationDigitalSignature;
+
     private SmsCbMessage(byte[] pdu) throws IllegalArgumentException {
         mHeader = new SmsCbHeader(pdu);
-        parseBody(pdu);
+        if (mHeader.format == SmsCbHeader.FORMAT_ETWS_PRIMARY) {
+            mBody = "ETWS";
+            // ETWS primary notification with security is 56 octets in length
+            if (pdu.length >= SmsCbHeader.PDU_LENGTH_ETWS) {
+                mPrimaryNotificationTimestamp = getTimestampMillis(pdu);
+                mPrimaryNotificationDigitalSignature = new byte[43];
+                // digital signature starts after 6 byte header and 7 byte timestamp
+                System.arraycopy(pdu, 13, mPrimaryNotificationDigitalSignature, 0, 43);
+            }
+        } else {
+            parseBody(pdu);
+        }
     }
 
     /**
@@ -157,6 +176,55 @@ public class SmsCbMessage {
     }
 
     /**
+     * Get the format of this message.
+     * @return {@link SmsCbHeader#FORMAT_GSM}, {@link SmsCbHeader#FORMAT_UMTS}, or
+     *         {@link SmsCbHeader#FORMAT_ETWS_PRIMARY}
+     */
+    public int getMessageFormat() {
+        return mHeader.format;
+    }
+
+    /**
+     * For ETWS primary notifications, return the emergency user alert flag.
+     * @return true to notify terminal to activate emergency user alert; false otherwise
+     */
+    public boolean getEtwsEmergencyUserAlert() {
+        return mHeader.etwsEmergencyUserAlert;
+    }
+
+    /**
+     * For ETWS primary notifications, return the popup flag.
+     * @return true to notify terminal to activate display popup; false otherwise
+     */
+    public boolean getEtwsPopup() {
+        return mHeader.etwsPopup;
+    }
+
+    /**
+     * For ETWS primary notifications, return the warning type.
+     * @return a value such as {@link SmsCbConstants#ETWS_WARNING_TYPE_EARTHQUAKE}
+     */
+    public int getEtwsWarningType() {
+        return mHeader.etwsWarningType;
+    }
+
+    /**
+     * For ETWS primary notifications, return the Warning-Security-Information timestamp.
+     * @return a timestamp in System.currentTimeMillis() format.
+     */
+    public long getEtwsSecurityTimestamp() {
+        return mPrimaryNotificationTimestamp;
+    }
+
+    /**
+     * For ETWS primary notifications, return the 43 byte digital signature.
+     * @return a byte array containing a copy of the digital signature
+     */
+    public byte[] getEtwsSecuritySignature() {
+        return mPrimaryNotificationDigitalSignature.clone();
+    }
+
+    /**
      * Parse and unpack the body text according to the encoding in the DCS.
      * After completing successfully this method will have assigned the body
      * text into mBody, and optionally the language code into mLanguage
@@ -334,6 +402,55 @@ public class SmsCbMessage {
         return body;
     }
 
+    /**
+     * Parses an ETWS primary notification timestamp and returns a currentTimeMillis()-style
+     * timestamp. Copied from com.android.internal.telephony.gsm.SmsMessage.
+     * @param pdu the ETWS primary notification PDU to decode
+     * @return the UTC timestamp from the Warning-Security-Information parameter
+     */
+    private long getTimestampMillis(byte[] pdu) {
+        // Timestamp starts after CB header, in pdu[6]
+        int year = IccUtils.gsmBcdByteToInt(pdu[6]);
+        int month = IccUtils.gsmBcdByteToInt(pdu[7]);
+        int day = IccUtils.gsmBcdByteToInt(pdu[8]);
+        int hour = IccUtils.gsmBcdByteToInt(pdu[9]);
+        int minute = IccUtils.gsmBcdByteToInt(pdu[10]);
+        int second = IccUtils.gsmBcdByteToInt(pdu[11]);
+
+        // For the timezone, the most significant bit of the
+        // least significant nibble is the sign byte
+        // (meaning the max range of this field is 79 quarter-hours,
+        // which is more than enough)
+
+        byte tzByte = pdu[12];
+
+        // Mask out sign bit.
+        int timezoneOffset = IccUtils.gsmBcdByteToInt((byte) (tzByte & (~0x08)));
+
+        timezoneOffset = ((tzByte & 0x08) == 0) ? timezoneOffset : -timezoneOffset;
+
+        Time time = new Time(Time.TIMEZONE_UTC);
+
+        // It's 2006.  Should I really support years < 2000?
+        time.year = year >= 90 ? year + 1900 : year + 2000;
+        time.month = month - 1;
+        time.monthDay = day;
+        time.hour = hour;
+        time.minute = minute;
+        time.second = second;
+
+        // Timezone offset is in quarter hours.
+        return time.toMillis(true) - (timezoneOffset * 15 * 60 * 1000);
+    }
+
+    /**
+     * Append text to the message body. This is used to concatenate multi-page GSM broadcasts.
+     * @param body the text to append to this message
+     */
+    public void appendToBody(String body) {
+        mBody = mBody + body;
+    }
+
     @Override
     public String toString() {
         return "SmsCbMessage{" + mHeader.toString() + ", language=" + mLanguage +