Class 0 SMS (flash SMS) On Android

Answer :

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.

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);  } 

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.