How to allow incoming and outgoing SMS only to specific phone numbers

Environment

• Knox SDK
• Samsung Knox Devices

Overview

This article provides information on how to allow incoming and outgoing SMS to specific numbers and blocking incoming/outgoing SMS to all other numbers using Knox SDK APIs.

To allow incoming and outgoing SMS to specific numbers, you need to:

1. Block incoming/outgoing SMS for all numbers.
2. Allow specific numbers for incoming/outgoing SMS.

How do I block incoming/outgoing SMS to all numbers?

Use Knox SDK’s setOutgoingSmsRestriction and setIncomingSmsRestriction APIs to block all incoming and outgoing SMS as specified below:

            EnterpriseDeviceManager edm = EnterpriseDeviceManager.getInstance(context);
            PhoneRestrictionPolicy phoneRestrictionPolicy = edm.getPhoneRestrictionPolicy();
            try {
            phoneRestrictionPolicy.setOutgoingSmsRestriction (".*");
            phoneRestrictionPolicy.setIncomingSmsRestriction (".*");
            } catch (SecurityException e) {
            Log.w(TAG, "SecurityException: " + e);
            }

How do I allow only specific numbers for incoming/outgoing SMS?

Use Knox SDK’s addOutgoingSmsExceptionPattern and addIncomingSmsExceptionPattern APIs to allow SMS to specific numbers only as specified below:

As an example, if the country code is "+91" and the mobile number that needs to be allowed for incoming and outgoing SMS is “9999999999”, use the following code:

		EnterpriseDeviceManager edm = EnterpriseDeviceManager.getInstance (context);
            PhoneRestrictionPolicy phoneRestrictionPolicy = edm.getPhoneRestrictionPolicy();
            try {
            phoneRestrictionPolicy. setOutgoingSmsRestriction (".*");
            phoneRestrictionPolicy. addOutgoingSmsExceptionPattern ("\\+919999999999");
            phoneRestrictionPolicy. setIncomingSmsRestriction (".*");
            phoneRestrictionPolicy. addIncomingSmsExceptionPattern ("\\+919999999999");
            } catch (SecurityException e) {
            Log.w(TAG, "SecurityException: " + e);
            }
            

Additional information

To read more about Knox SDK, please refer Knox SDK API Reference.