WO2015043130A1

WO2015043130A1 - Pos machine, and method and apparatuses for protecting sensitive data in pos machine

Info

Publication number: WO2015043130A1
Application number: PCT/CN2014/071180
Authority: WO
Inventors: 吴冬周; 肖锋
Original assignee: 福建联迪商用设备有限公司
Priority date: 2013-09-30
Filing date: 2014-01-23
Publication date: 2015-04-02
Also published as: CN103544789B; CN103544789A

Abstract

Disclosed are a POS machine, and a method and apparatuses for protecting sensitive data in the POS machine. The method for protecting sensitive data in the POS machine comprises: detecting whether a pin level of a connection protecting switch changes; when it is detected that the pin level changes, determining whether the pin level is restored to an original state within a preset time; if not, deleting the sensitive data stored in the POS machine, and if yes, re-detecting whether the pin level changes. The present invention also provides two apparatuses for protecting the sensitive data in the POS machine. By using the two apparatuses, interference of an interference signal to the POS machine can be effectively filtered, and the interference resistance and stability of the POS machine are improved.

Description

POS machine, method and device for protecting sensitive data in POS machine

Technical field

The invention relates to a POS machine and a method and device for protecting sensitive data in a POS machine.

Background technique

With the continuous development of modern business and the continuous updating of management technology, the application of POS machines has also developed rapidly. According to the safety requirements of financial equipment for international PCI organizations and domestic BCTCs, when trading through POS machines, some key sensitive data must be protected during the transaction to prevent sensitive information from being stolen without the cardholder's knowledge. In the application number is 201210165731.2, the application name is "a protection method and protection device for sensitive data in a POS machine", and a protection method for a sensitive data in a POS machine and a protection device thereof are disclosed, in which the method detects whether the POS machine is Protected by sensitive data, when the POS is attacked, the sensitive data in the security zone of the POS is cleared to protect sensitive information from being stolen. The current protection method is to set a data protection switch on the POS machine to detect whether the POS machine is attacked. When the POS machine is in normal use, the protection switch is applied with a certain pressure to close the protection switch; when the POS machine is attacked, the protection switch is disconnected, and the POS machine clears all sensitive information on the transaction. However, during the use of the POS machine, it often encounters various external factors such as device drop, vibration, ESD, thermal shock, etc., causing the protection switch to instantaneously open and close, causing the POS machine to trigger safety protection. In response, the POS machine clears all sensitive information, causing unforeseen circumstances such as a transaction interruption.

technical problem

The purpose of the present invention is to overcome the deficiencies of the prior art described above, and to provide a POS machine that can prevent POS machines from being accidentally deleted due to interference from external factors, and a method and apparatus for protecting sensitive numbers in a POS machine.

Technical solution

A method for protecting sensitive data in a POS machine, wherein the sensitive data protection device in the POS device uses a protection switch to detect whether an external attack is performed. The method includes the following steps: S1: detecting whether a pin level of the connection protection switch changes. Wherein, the protection switch detects that the POS casing is disconnected from the pin when it is opened; S2, when detecting that the pin level changes, determining whether the pin level returns to the original state within a preset time threshold If not, proceed to step S3, and if yes, return to step S1; S3, clear the sensitive data stored in the POS machine.

The protective switch is a pot switch, and the pot switch is disposed between the front cover and the rear cover of the POS casing.

The preset time threshold is 200 to 250 ms.

An apparatus for protecting sensitive data in a POS machine, the apparatus for protecting sensitive data in a POS machine comprising a CPU electrically connected to a POS machine storage unit, the storage unit storing sensitive data, the protecting the sensitive data in the POS machine The device further includes a protection switch connected to a pin of the CPU, the CPU comprising: a detecting unit configured to detect whether a pin level of the connection protection switch is changed, wherein the protection switch detects that the POS case is opened Disconnecting from the pin; the determining unit is configured to: when the detecting unit detects that the pin level changes, determine whether the pin level returns to the original state within a preset time threshold; the clearing unit is configured to be used The determining unit determines that the pin level is not restored to the original state within the preset time threshold, and the sensitive data stored by the storage unit is cleared.

Wherein, the protection switch is a pot piece switch, the number of the pot piece switch is three, and the pot piece switch is respectively disposed at an edge of a button circuit board of the POS machine, and each pot piece switch is The pot switch button set on the keypad of the POS machine corresponds.

The preset time threshold is 200 to 250 ms.

The judging unit is a counter including a comparison register, and the counter is used to start timing when the detecting unit detects that the pin level changes, and stop timing when the pin level returns to the original state, when the timing is timed. An electrical signal is sent to the clearing unit when the preset time threshold of the compare register is exceeded.

An apparatus for protecting sensitive data in a POS machine, the apparatus for protecting sensitive data in a POS machine comprising a CPU electrically connected to a storage unit of a POS machine, the storage unit storing sensitive data, the POS machine further comprising a protection switch The protection switch is connected to a pin of the CPU through a low pass filter; the protection switch detects disconnection from the low pass filter when the POS case is opened; the low pass filter is used to filter the high frequency pulse and Transmitting a switching signal in a threshold frequency range to the CPU; the CPU includes: a detecting unit configured to detect whether a pin level changes; and a clearing unit configured to when the detecting unit detects a change in a pin level , clear sensitive data stored in the POS machine.

Among them, it also includes a built-in power supply that is electrically connected to the CPU.

A POS machine, the POS casing includes a front cover and a rear cover, the front cover and the rear cover are fixed together by a screw pair, and the POS machine is provided with the above device for protecting sensitive data in the POS machine, at the POS The button switch button corresponding to the pot chip switch is arranged on the keyboard of the machine button. When the front cover of the POS machine case is fastened to the back cover, the button switch button of the POS machine is pressed by the pressure of the front cover downward pressure The switch is in the closed state.

Beneficial effect

The invention has the beneficial effects that the invention filters the input signal of the protection switch of the sensitive data in the POS machine, and filters out the interference of the protection switch input signal by various external factors such as device drop, vibration, ESD, thermal shock and the like. Avoid interference signals caused by accidental deletion of transaction data caused by sensitive data, improve the anti-interference and stability of POS.

DRAWINGS

1 is a flowchart of a method for protecting sensitive data in a POS machine according to an embodiment of the present invention;

2 is a schematic structural diagram of a protection switch in a device for protecting sensitive data in a POS device according to an embodiment of the present invention;

3 is a schematic structural diagram of an apparatus for protecting sensitive data in a POS machine according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of another apparatus for protecting sensitive data in a POS machine according to an embodiment of the present invention.

The main component symbol description:

1: memory unit; 2: CPU; 3: protection switch; 4: detection unit; 5: judgment unit; 6: clearing unit; 7: low-pass filter; 8: built-in power supply; 9: pot chip switch; 10: pot chip switch button; 11: POS machine button keyboard; 12: front cover; 13: POS machine button circuit board.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the invention

The detailed description of the technical contents, structural features, and the objects and effects of the present invention will be described in detail below with reference to the accompanying drawings.

Example 1

Please refer to FIG. 1 , which is a flowchart of a method for protecting sensitive data in a POS machine according to an embodiment of the present invention. The method includes the following steps:

S1: Detecting whether a pin level of the connection protection switch is changed, wherein the protection switch detects that the POS case is disconnected from the pin when it is opened.

Sensitive data is stored in the internal storage area of the POS, and the sensitive data includes a key used to encrypt the cardholder's security data. Some lawless elements open the POS case when the cardholders are not paying attention to steal these sensitive data. Therefore, in order to prevent the sensitive data of the POS machine from being stolen, a protection switch 3 is provided in the POS machine, and the protection switch 3 detects that the POS machine case is opened and disconnected from the pin, so the level of the pin changes. Detecting whether the pin level connected to the protection switch 3 has changed can detect whether the POS machine is attacked by an external attack that steals sensitive information.

S2. When it is detected that the pin level changes, it is determined whether the pin level returns to the original state within a preset time threshold. If not, the process proceeds to step S3, and if yes, returns to step S1.

In the actual use process, when the POS machine encounters interference factors such as equipment drop, vibration, ESD, thermal shock, etc., the protection switch 3 will instantaneously open and close the jump and cause the pin level to change. When a pin level change is detected, it is mistaken for an external attack, which triggers the POS machine to clear all sensitive information, causing the transaction to be interrupted. In order to avoid the influence of the above interference factors, a time threshold is preset in the method, and when the change of the pin level is detected, it is judged whether the pin level returns to the original state within the preset time threshold. Because the transition caused by these interference factors is mainly distributed between the ns level and the ms level, when the pin level returns to the original state within the preset time threshold, the pin level change is due to the interference factor. Caused, so the pin level changes are filtered out, and the process returns to step S1. When the pin level is not restored to the original state within the preset time threshold, the pin level change is due to an external attack. Therefore, step S3 is performed.

S3. Clear sensitive data stored in the POS machine.

When it is determined in step S2 that the pin level change is caused by an external attack, the sensitive data stored in the POS machine is cleared.

In this embodiment, the protection switch 3 is a pot switch 9, and the pot switch 9 is disposed between the front cover 12 and the rear cover of the POS casing.

In this embodiment, the preset time threshold is 200 to 250 ms. The protection switch 3 hopping caused by the interference of external factors such as equipment drop, vibration, ESD, thermal shock and other impacts encountered by the POS machine is mainly distributed in the ns level to the ms level, so the preset time threshold is set to 200~ 250ms, can effectively filter out the influence of these interference factors, and can timely detect whether the protection switch 3 is subject to external attacks.

The method for protecting sensitive data in a POS machine determines the input signal of the protection switch 3 of the sensitive data in the POS machine, and filters out various external factors such as device drop, vibration, ESD, thermal shock and the like to protect the input signal of the protection switch. Interference, avoiding interference signals, causing sensitive data to be deleted accidentally, improving the anti-interference and stability of the POS.

Example 2

Please refer to FIG. 3 , which is a structural block diagram of an apparatus for protecting sensitive data in a POS machine according to an embodiment of the present invention. The device for protecting sensitive data in the POS machine comprises a CPU 2 electrically connected to the POS storage unit 1, the storage unit 1 storing sensitive data, and the device for protecting sensitive data in the POS device further comprises a pin connection with the CPU 2. The protection switch 3, the CPU 2 includes a detecting unit 4, a determining unit 5 and a clearing unit 6; the detecting unit 4 is configured to detect whether a pin level of the connection protection switch 3 is changed, wherein the protection switch 3 detects Determining with the pin when the POS case is opened; the determining unit 5 is configured to determine the pin level within a preset time threshold when the detecting unit 4 detects a change in the pin level Whether the original state is restored; the clearing unit 6 is configured to: when the determining unit 5 determines that the pin level is not restored to the original state within the preset time threshold, clear the sensitive data stored by the storage unit 1.

In this embodiment, the determining unit 5 is a counter including a comparison register, and the counter is used to start timing when the detecting unit 4 detects a change in the pin level and when the pin level returns to the original state. The timing is stopped, and an electrical signal is sent to the clearing unit 6 when the timing time exceeds the preset time threshold of the comparison register.

In this embodiment, the protection switch is a dome switch 9, and the dome switch 9 is connected to the detection pin. The pot chip switch is small in size and responsive, and is suitable for being installed in a small-sized device such as a POS machine. In this embodiment, the pot chip switch 9 is separately set in the POS machine casing. One side of the switch is closely attached to the back cover of the POS machine. When the front cover 12 of the POS is fastened to the back cover, the front cover 12 is just in close contact with the other side of the switch 9 to make the switch. 9 is in a closed state. When the POS case is opened, the pan switch 9 is turned from the closed state to the open state, so the detection pin detects a change in the level signal triggering the clearing of the sensitive data. Since the button stroke of the pot switch 9 is very short, when the POS casing is slightly opened, the pan switch 9 is turned from the closed state to the disconnected state, so that the POS casing can be sensitively reacted. Effectively guarantee the sensitivity of the method of protecting sensitive data in POS machines.

As a modification of this embodiment, please refer to FIG. 2, which is a schematic structural diagram of a protection switch in a device for protecting sensitive data in a POS machine according to an embodiment of the present invention. The protective switch 3 is a pot switch 9, the number of the pot switch 9 is three, and the pot switch 9 is respectively disposed at the edge of the POS button circuit board 13, each pot The touch 9 switch corresponds to the dome switch button 10 provided on the POS machine key pad 11. When the front cover 12 of the POS casing is fastened to the back cover, the dome switch button 10 disposed on the POS button keypad 11 is subjected to the downward pressure of the front cover 12, so that the dome switch 9 is closed. Pass state. When the POS casing is opened, when the one or more of the three dome switches 9 are turned from the on state to the off state, the detecting unit 4 can detect the detection pin level change. . Therefore, setting the three pot chip switches 9 and setting them on the edge of the POS machine key keyboard 11 can greatly improve the detection sensitivity of the detecting pot chip switch 9.

In this embodiment, the preset time threshold is 200 to 250 ms.

The device for protecting sensitive data in the POS machine judges the input signal of the protection switch 3 of the sensitive data in the POS machine, and filters out the input signals of the protection switch due to various external factors such as device drop, vibration, ESD, thermal shock and the like. Interference, avoiding interference signals, causing sensitive data to be deleted accidentally, improving the anti-interference and stability of the POS.

Example 3

As shown in FIG. 4, another apparatus for protecting sensitive data in a POS machine according to an embodiment of the present invention is provided. The device for protecting sensitive data in the POS machine comprises a CPU 2 electrically connected to the storage unit 1 of the POS machine, the storage unit 1 storing sensitive data, the POS machine further comprising a protection switch 3, the protection switch 3 passing a low The pass filter 7 is connected to the pin of the CPU 2; the protection switch 3 detects disconnection from the low pass filter 7 when the POS case is opened, and the low pass filter 7 is used to filter the high frequency pulse and set the threshold The switching signal is sent to the CPU 2, and the CPU 2 includes a detecting unit 4 and a clearing unit 6 for detecting whether the pin level has changed. The clearing unit 6 is configured to perform the detecting. When unit 4 detects a change in pin level, it clears the sensitive data stored in the POS.

In this embodiment, the low-pass filter 7 includes a resistor and a capacitor. The resistor is connected in series between the protection switch 3 and the CPU 2 detection pin. One end of the capacitor is connected to the CPU 2 detection pin, and the other end is grounded. The pass frequency of the low pass filter can be set by setting the values of the capacitance and the resistance. Since the pulse width of the interference signal is generally less than 200 ms, the pass pulse width of the low pass filter 7 is set to 200 to 250 ms, that is, the pass frequency of the low pass filter is less than 4 to 5 Hz. The values of the resistance and capacitance can be calculated according to the formula f = 1/2 πRC. In the present embodiment, the low pass filter 7 is an RC filter, but the present invention is not limited to the RC filter, and a low pass filter having a frequency less than 4 to 5 Hz, which is well known to those skilled in the art, is The scope of protection of the present invention.

In this embodiment, a built-in power supply 8 electrically connected to the CPU 2 is further included, and the built-in power supply 8 has a button battery disposed on the circuit board. The built-in power supply 8 provides power to the device for protecting sensitive data of the POS when the POS machine is in use, so that the device can protect sensitive data from being stolen when the POS is turned on or off.

In this embodiment, a low pass filter 7 is connected in series between the protection switch and the pin, so that the input signal of the protection switch 3 passes through the low pass filter 7 first, and the pass frequency of the low pass filter 7 is set. The protection switch 3 level jump caused by the interference factor can be filtered out, and the solution does not need to compare the input signal of the protection switch with the preset time threshold, thereby greatly reducing the response time of the device to the external attack signal, and clearing the storage in time. The sensitive data in unit 1 makes the data better protected.

Example 4

This embodiment is a POS machine. The POS casing includes a front cover 12 and a rear cover. The front cover 12 and the rear cover are fixed together by a screw pair. The POS machine includes the protection POS described in Embodiment 2. The device for sensitive data in the machine is provided with a pot switch button 10 corresponding to the pot chip switch 9 on the POS machine keypad 11 when the front cover 12 of the POS case is fastened to the back cover. The sheet switch button 10 is pressed against the pot switch 9 by the downward pressure of the front cover 12 to be in a closed conduction state.

The device for protecting sensitive data in the POS machine is set on the POS machine, which can protect the sensitive data in the POS machine from being stolen, and can filter the input of the protection switch due to various external factors such as device drop, vibration, ESD, thermal shock and the like. Signal interference, avoiding interference signals, causing sensitive data to be deleted accidentally, improving the anti-interference and stability of the POS machine.

The above is only the embodiment of the present invention, and is not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformation of the present invention and the contents of the drawings may be directly or indirectly applied to other related technologies. The fields are all included in the scope of patent protection of the present invention.

Claims

A method for protecting sensitive data in a POS machine, wherein the sensitive data protection device in the POS device uses a protection switch to detect whether an external attack is performed, and the method includes the following steps:

S1, detecting whether a pin level of the connection protection switch is changed, wherein the protection switch detects that the POS machine case is opened and disconnected from the pin;

S2, when it is detected that the pin level changes, it is determined whether the pin level returns to the original state within a preset time threshold, if not, proceeds to step S3, and if so, returns to step S1;

S3. Clear sensitive data stored in the POS machine.

The method for protecting sensitive data in a POS machine according to claim 1, wherein the protection switch is a pot switch, and the pot switch is disposed on a front cover and a rear of the POS housing. Between the covers.

3. The method of protecting sensitive data in a POS machine according to claim 1, wherein the preset time threshold is 200 to 250 ms.

4. A device for protecting sensitive data in a POS machine, comprising a CPU electrically connected to a POS storage unit, said storage unit storing sensitive data, wherein said means for protecting sensitive data in the POS machine further comprises A protection switch for a pin connection of the CPU, the CPU comprising:

a detecting unit, configured to detect whether a pin level of the connection protection switch is changed, wherein the protection switch detects that the POS machine case is opened and is disconnected from the pin;

a determining unit, configured to: when the detecting unit detects that the pin level changes, determine whether the pin level returns to a original state within a preset time threshold;

And a clearing unit, configured to: when the determining unit determines that the pin level is not restored to the original state within the preset time threshold, clear the sensitive data stored by the storage unit.

The device for protecting sensitive data in a POS machine according to claim 4, wherein the protection switch is a pot chip switch, and the pot chip switch is disposed on a front cover and a rear of the POS machine casing. Between the covers.

The device for protecting sensitive data in a POS machine according to claim 4, wherein the protection switch is a pot switch, and the number of the pot switch is three, the pot piece The switches are respectively disposed on the edge of the button circuit board of the POS machine, and each of the pot chip switches corresponds to the pot chip switch button set on the keyboard of the POS machine.

7. The apparatus for protecting sensitive data in a POS machine according to claim 4, wherein the preset time threshold is 200 to 250 ms.

8. The apparatus for protecting sensitive data in a POS machine according to claim 4, wherein said determining unit is a counter including a comparison register, said counter being used when said detecting unit detects that a pin level has occurred. The timing starts when the change occurs and stops when the pin level returns to the original state. When the timing exceeds the preset time threshold of the comparison register, an electrical signal is sent to the clearing unit.

9. A device for protecting sensitive data in a POS machine, comprising a CPU electrically connected to a storage unit of a POS machine, said storage unit storing sensitive data, wherein said POS machine further comprises a protection switch, said protection The switch is connected to the pin of the CPU through a low pass filter;

The protection switch detects disconnection from the low pass filter when the POS case is opened;

The low pass filter is configured to filter high frequency pulses and send a switching signal within a threshold frequency range to the CPU;

The CPU includes:

a detecting unit for detecting whether a pin level has changed;

And a clearing unit, configured to clear sensitive data stored in the POS when the detecting unit detects a change in the pin level.

10. Apparatus for protecting sensitive data in a POS machine according to any of claims 4-8, further comprising a built-in power supply electrically coupled to the CPU.

A POS machine, the POS casing comprising a front cover and a rear cover, the front cover and the rear cover being fixed together by a screw pair, characterized by comprising the method of any one of claims 5-6 The device for protecting sensitive data in the POS machine is provided with a pot switch button corresponding to the pot chip switch on the keypad of the POS machine. When the front cover of the POS machine case is fastened to the back cover, the pot switch The button is pressed against the lid switch by the pressure of the front cover downwards to bring it into a closed state.