Class 0 SMS (flash SMS) on Android

Question

As I know that Nokia and some others phone (like iPhone) are able to sent and receive class 0 SMS , is it possible for android ? Do Android have the API?

What is flash SMS?

Flash SMS is an SMS which is displayed on the phone screen immediately upon arrival.

Unless you choose to save the flash message, it will disappear upon navigating away and will not be saved in your inbox.

If several flash messages are sent to one phone, only the latest message will be displayed, and all the previous ones will be overwritten.

Class 0: Indicates that this message is to be displayed on the MS immediately and a message delivery report is to be sent back to the SC. The message does not have to be saved in the MS or on the SIM card (unless selected to do so by the mobile user).

Solution 1

For rooted Android it is possible to bypass an API and send Class 0 SMS. There is a project on Git Hub called ZeroSMS:

ZeroSMS is a proof-of-concept demonstrating a way to send Class 0 SMS on android >=2.3.

Note: this only works on versions 2.2 -> 4.1.2, the sendRawPdu method was removed, so you will need to find a new way to do this.

Solution 2

It was possible to send Flash SMS (that's the term for class 0 SMS) before Android 2.2. Google removed the sendRawPdu API, so even if you used reflection, you wouldn't be able to do it.

Here's how I did it previously (this was tested on Android 1.6 and worked)

private void sendSms(String phone, String sms) {
    if ((phone == null) || (sms == null) || (phone.length() == 0)
            || (sms.length() == 0)) {
        String message = "Phone or message empty!!!";
        Toast notification = Toast.makeText(getBaseContext(), message,
                Toast.LENGTH_SHORT);
        notification.show();
        return;
    }

    // SecurityManager oldSM = System.getSecurityManager();
    // MySecurityManager newSM = new MySecurityManager();
    // System.setSecurityManager(newSM);

    // ServiceManager.getService("isms")
    // ServiceManager.getService("isms");

    SmsManager m = SmsManager.getDefault();
    PendingIntent sentIntent = PendingIntent
            .getBroadcast(this, 0, new Intent(
                    MessageStatusReceiver_MESSAGE_STATUS_RECEIVED_ACTION),
                    0);

    PendingIntent deliveryIntent = PendingIntent.getBroadcast(this, 0,
            new Intent(SmsReceiverService_MESSAGE_SENT_ACTION), 0);

    // String sms = "Message self-destroyed!!!";
    // String phone = "93634096";

    long NOW = System.currentTimeMillis();
    String time = String.valueOf(NOW);

    // // m.sendTextMessage(phone, null, sms, sentIntent, deliveryIntent);
    // working // m.sendTextMessage(phone, null, sms, null, null);
    byte[] bb = new byte[1];
    Method m2 = null;
    try {
        m2 = SmsManager.class.getDeclaredMethod("sendRawPdu",
                bb.getClass(), bb.getClass(), PendingIntent.class,
                PendingIntent.class);
    } catch (SecurityException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (NoSuchMethodException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    // send message

    SmsMessage.SubmitPdu pdus = SmsMessage.getSubmitPdu(null, phone, sms,
            false);

    // http://android.git.kernel.org/?p=platform/frameworks/base.git;a=blob;f=telephony/java/android/telephony/gsm/SmsMessage.java;h=9ccfa90d2e24e5caea26c1deac641b3c31ae56d4;hb=c883b143ba2b8bfe2f2033d00dee9ff733f1b59c

    boolean submitted = false;
    try {
        byte[] encodedMessage = pdus.encodedMessage;
        // byte[0] = mtiByte
        // byte[1] = TP Message Reference
        // byte[2] = length of source phone
        // byte[3..length] = phone
        // protocol identifier
        int msgLen = encodedMessage[2] / 2;
        // +2 -> length of source phone
        // +2 -> for 91 after the length
        // +1 -> TP PID
        int indexTPDCS = msgLen + 5;
        byte TPDCS = encodedMessage[indexTPDCS];
        // System.out.println(TPDCS);
        System.out.println(getHexString(encodedMessage));
        byte[] changedMessage = encodedMessage.clone();
        // Set bit 4 to 1 using OR (|), indicating there is a message class
        // Set bit 0 and 1 to 0 using AND (&), indicating class 0
        byte newTPDCS = (byte) ((TPDCS | 0x10) & 0xFC); // Flash SMS
        changedMessage[indexTPDCS] = newTPDCS; // Class 0
        System.out.println(getHexString(changedMessage));
        // Log.d(SmsScheduler_TAG, getHexString(changedMessage));
        boolean send = true;
        if (send) {
            m2.invoke(m, pdus.encodedScAddress, changedMessage, null, null);

            // sendSMS(HexDump.bytesToHexString(pdus.encodedScAddress),
            // HexDump.bytesToHexString(changedMessage), null);

            String message = "Flash SMS sent to " + phone
                    + " successfully!";
            Toast notification = Toast.makeText(getBaseContext(), message,
                    Toast.LENGTH_SHORT);
            notification.show();
            Log.d(SmsScheduler_TAG, message);
            submitted = true;
        }
    } catch (IllegalArgumentException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (UnsupportedEncodingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IllegalAccessException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (InvocationTargetException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

            // not essential, saves the SMS sent. 
    if (submitted) {
        ContentValues values = new ContentValues();
        values.put(ADDRESS, phone);
        values.put(DATE, time);
        values.put(READ, 0);
        values.put(STATUS, -1);
        values.put(TYPE, MESSAGE_TYPE_SENT);
        values.put(BODY, sms);

        Uri inserted = getContentResolver().insert(
                Uri.parse("content://sms"), values);
    }

    // System.setSecurityManager(oldSM);

}

Solution 3

Scrool's answer is indeed correct, https://stackoverflow.com/a/12873325/3082310 , as ZeroSMS does send flash SMS's; however, it is a Proof-of-Concept and only supports SMS's with 7-bit encoding.

For proper encoding it seems there is a need to modify the code and add if-then or switch-case statements: For 7-bit coding, as in english

use (byte)0xF0

For 16-bit encoding, UCS-2 encoding

use (byte) 0x18

Otherwise, junk characters appear if you enter unsupported language.

Comments

[harshit]

Hey, do you have any idea what does other three classes mean? I have been searching for about two hours, but I am not able to find any thing.

[xDragonZ]

Ok , I will select this as the ans since it won't work after Android 2.2

[chuacw]

This works only on CyanogenMod ROMs, as it requires signing the APK with CyanogenMod certs.

[Viral]

I tried to install Zero Sms app on my rooted phone, but the installation failed for both signed and normal apk. Will this Zero Sms work only with CyanogenMod ? I need this for kitkat version

[Ahmad]

Does it support on latest Android Versions