Point-of-sale system having a secure touch mode
A consumer terminal for a point-of-sale (POS) system used in performing a POS transaction between a merchant and a consumer. The consumer terminal includes a display, a touch panel, first electronics in a physically secure area and second electronics in a non-secure area. The first electronics are configured to display a series of screens to guide a consumer through the POS transaction. The second electronics comprises a microcontroller and a secure processor. Upon receiving a request for secure data from the non-secure processor, the secure processor sends a notification to the non-secure processor to exit pass-through mode and enter a secure touch mode. Upon completion of PIN entry, the secure processor instructs non-secure processor to exit secure touch mode and return to pass-through mode.
1. A method of processing secure inputs received at a user interface, the method comprising:
receiving, at a secure processor of a computing device, a personal identification number (PIN) entry request from a non-secure processor of the computing device;
receiving, at a touch panel of the user interface, touch events of a PIN entry;
instructing, by the secure processor in response to the PIN entry request, the non-secure processor to enter a secure touch mode such that the touch events of the PIN entry are not transmitted to the non-secure processor;
processing, by the secure processor, the touch events of the PIN entry during the secure touch mode;
determining, by the secure processor, that the touch events of the PIN entry are complete;
instructing, by the secure processor in response to the determination that the touch events of the PIN entry are complete, the non-secure processor to exit the secure touch mode and enter a pass-through mode;
receiving, at the touch panel of the user interface, additional touch events during the pass-through mode; and
processing, by the non-secure processor, the additional touch events during the pass-through mode.
2. The method of claim 1 wherein processing the touch events of the PIN entry comprises:
receiving, at an analog front end, the touch events into the touch panel;
generating, by a microcontroller coupled to the analog front end, digital data from the touch events into the touch panel; and
transmitting, by the microcontroller, the generated digital data to the secure processor for subsequent providing by the secure processor to a merchant terminal.
3. The method of claim 1 wherein processing the touch events for the PIN entry comprises:
receiving, at an analog front end, the touch events into the touch panel;
generating, by a microcontroller coupled to the analog front end, digital data from the touch events;
transmitting, by the microcontroller, the generated digital data to the secure processor;
encrypting, by the secure processor, the digital data into an encrypted PIN block; and
transmitting, by the secure processor, the encrypted PIN block to the non-secure processor.
4. The method of claim 1 wherein processing the touch events of the PIN entry comprises:
receiving, at an analog front end, the touch events into the touch panel;
generating, by a microcontroller coupled to the analog front end, digital data from the touch events into the touch panel; and
transmitting, by the microcontroller, the generated digital data to the secure processor for subsequent providing by the secure processor to a payment processing system.
5. The method of claim 1 , wherein instructing the non-secure processor to enter the secure touch mode comprises transmitting a message from the secure processor to the non-secure processor.
6. The method of claim 1 , wherein instructing the non-secure processor to exit the secure touch mode comprises transmitting a message from the secure processor to the non-secure processor.
7. The method of claim 1 , wherein instructing the non-secure processor to exit the secure touch mode comprises:
determining that the touch input from the consumer is complete; and
instructing the non-secure processor to exit the secure mode based on the determination.
8. The method of claim 1 , further comprising receiving an acknowledgement message at the secure processor from the non-secure processor upon the non-secure processor exiting the secure touch mode.