CN103559459A - Dynamic shielding protection device and method for safety chip - Google Patents
Dynamic shielding protection device and method for safety chip Download PDFInfo
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- CN103559459A CN103559459A CN201310544799.6A CN201310544799A CN103559459A CN 103559459 A CN103559459 A CN 103559459A CN 201310544799 A CN201310544799 A CN 201310544799A CN 103559459 A CN103559459 A CN 103559459A
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- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
- G06F21/70—Protecting specific internal or peripheral components, in which the protection of a component leads to protection of the entire computer
- G06F21/71—Protecting specific internal or peripheral components, in which the protection of a component leads to protection of the entire computer to assure secure computing or processing of information
- G06F21/72—Protecting specific internal or peripheral components, in which the protection of a component leads to protection of the entire computer to assure secure computing or processing of information in cryptographic circuits
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Abstract
The invention relates to a dynamic shielding protection device and a dynamic shielding protection method for a safety chip. The device comprises a signal generating module, M first metal wire groups, a second metal wire group, a grouped control module and a signal comparison module, wherein the signal generating module is used for generating first signals and second signals, the second metal wire group is arranged in a middle metal layer of the safety chip, the second signals are transmitted through the second metal wire group, the grouped control module is used for selecting one first metal wire group for transmitting the first signals, and the signal comparison module is used for comparing the first signals transmitted by the first metal wire group with the second signals transmitted by the second metal wire group and triggering the safety protection measures of the safety chip according to the comparison results. The physical cost and power consumption of the dynamic shielding system can be reduced.
Description
Technical field
The present invention relates to microelectronic, relate in particular to a kind of dynamic shielding protective device and method for safety chip.
Background technology
Safety chip, for objects such as information storage, data transmission, requires this class chip can resist various attack means, to prevent that assailant from obtaining, revising or using the secret information on this class chip conventionally.Be wherein to use on the metal wire of microprobe contact below chip passivation layer surface to read a Data within the chip, coordinate focused ion beam (Focused Ion Beam is called for short: FIB) technology is modified to metal wire simultaneously.
Masking technique can protect chip not to be subject to the attack of above-mentioned means, and masking technique is divided two kinds: a kind of is static masking technique, and another kind is dynamic shielding technology.Wherein, static masking technique is to use simple metal level or metal grill to cover chip, prevents assailant's observation and the detection of microprobe; Yet the metal that static state is covered can be removed, revise by chemical mordant or other technologies.Dynamic shielding technology is to cover chip by many metal line, and drives the signal that has dynamic change on metal wire, once certain metal wire is removed, cuts off or be shorted on other metal wires, masking system can detect the also safeguard measure of triggering following.The two is compared, and the security of dynamic shielding technology is higher.
For dynamic shielding system, for chip integral body is covered, in order to increase FIB, revise the difficulty of metal wire simultaneously, need on the top layer metallic layer of chip, arrange a large amount of metal wires, for each metal wire, with a Dynamic Signal, drive.If the metal wire quantity of using is less; it is Dynamic Signal negligible amounts; the area that each wires covers is so just larger; the length that is each metal wire is just longer; certainly will require Dynamic Signal must there is larger driving force; need to use larger driving element, cause the overall physics cost of protection system higher.If the metal wire quantity of using is larger; be that Dynamic Signal quantity is larger; the area that each wires covers is so just smaller; the length that is each metal wire is just shorter, now, although each driving element is little; but because metal wire quantity has increased; the overall physics cost of protection system is not low yet, and meanwhile, signal increase also can increase the power consumption of system.
Summary of the invention
The invention provides a kind of dynamic shielding protective device and method for safety chip, in order to realize physics cost and the power consumption that reduces dynamic shielding system.
The invention provides a kind of dynamic shielding protective device for safety chip, comprising:
Signal generation module, for generating first signal and secondary signal;
M the first metal wire group, is arranged in the top layer metallic layer of described safety chip, and each first metal wire group comprises N metal line, and wherein, M is more than or equal to 2 natural number, and N is more than or equal to 2 natural number;
A second metal wire group, comprises N metal line, is arranged in the intermediate metal layer of described safety chip, and described secondary signal is via described the second metal wire group transmission;
Grouping control module, for selecting a first metal wire group to transmit described first signal;
Signal comparison module, compares for the first signal to via described the first metal wire group transmission with via the secondary signal of described the second metal wire group transmission, triggers the safety precautions of described safety chip according to comparative result.
The present invention also provides a kind of dynamic shielding guard method for safety chip, M the first metal wire group is arranged in the top layer metallic layer of described safety chip, a second metal wire group is arranged in the intermediate metal layer of described safety chip, each first metal wire group comprises N metal line, described the second metal wire group comprises N metal line, wherein, M is more than or equal to 2 natural number, and N is more than or equal to 2 natural number;
Described method comprises:
Generate first signal and secondary signal;
Select a first metal wire group to transmit described first signal, described the second metal wire group is transmitted described secondary signal;
To the first signal via described the first metal wire group transmission with via the secondary signal of described the second metal wire group transmission, compare, according to comparative result, trigger the safety precautions of described safety chip.
In the present invention, a metal wire group in a first signal demand motive M the first metal wire group, other metal wire groups are not driven, with do not divide into groups to compare, the length of first signal has reduced and the requirement of its driving force has been reduced, thereby has reduced physics cost and the power consumption of dynamic shielding system.
Accompanying drawing explanation
Fig. 1 is that the present invention is for the structural representation of the dynamic shielding protective device embodiment of safety chip;
Fig. 2 is that the present invention is for the schematic flow sheet of the dynamic shielding guard method embodiment of safety chip;
Fig. 3 organizes the structural representation of switching signal generation unit in the present invention dynamic shielding protective device embodiment Fig. 1 for safety chip.
Embodiment
Below in conjunction with specification drawings and specific embodiments, the invention will be further described.
As shown in Figure 1; for the structural representation of the present invention for the dynamic shielding protective device embodiment of safety chip, this device can comprise signal generation module 11, M the first metal wire group 121,122 ... 12M; a second metal wire group 13, grouping control module 14 and signal comparison module 15.The output terminal of signal generation module 11 is connected with the second metal wire group 13 with the input end of grouping control module 14 respectively, grouping control module 14 and M the first metal wire group 121,122 ... 12M connects, and the input end of signal comparison module 15 is connected with the output terminal of grouping control module 14 with the second metal wire group 13 respectively.
M the first metal wire group 121,122 ... 12M is arranged in the top layer metallic layer of safety chip, and cover full chip or segment chip, each first metal wire group comprises N metal line, wherein, M is more than or equal to 2 natural number, and N is more than or equal to 2 natural number; The second metal wire group 13 comprises N metal line, is arranged in the intermediate metal layer of safety chip.
Wherein, signal generation module 11 is for generating first signal and secondary signal; The length of first signal and secondary signal is N bit.Alternatively, first signal and secondary signal identical or the two between meet particular kind of relationship, for example: the two is contrary or have a specific function relation.Alternatively, signal generation module 11 specifically can adopt counter, random signal generator, linear feedback shift register or their combination to realize.
Secondary signal is via the second metal wire group 13 transmission.
The first signal that grouping control module 14 control signal generation modules 11 generate drives M the first metal wire group 121,122 ... which group metal wire in 12M is selected M the first metal wire group 121,122 simultaneously ... the signal transmitting on which group metal wire in 12M is as the input signal of signal comparison module 15.
As shown in Figure 2, be the schematic flow sheet of the present invention for the dynamic shielding guard method embodiment of safety chip, the method can be applied to structural representation shown in Fig. 1, and the method can comprise the steps:
In the present embodiment, when this device work, a metal wire group in a first signal demand motive M the first metal wire group, other metal wire groups are not driven, with do not divide into groups to compare, the length of first signal has reduced and the requirement of its driving force has been reduced, thereby has reduced physics cost and the power consumption of dynamic shielding system.
Alternatively, structural representation shown in Figure 1 again, grouping control module 14 can comprise group selection signal generation unit 140, the first group selection unit 141, the second group selection unit 142, group switching signal generation unit 143 and group selection signal switch unit 144.The output terminal of group selection signal generation unit 140 is connected with the input end of group selection signal switch unit 144 with the output terminal of group switching signal generation unit 143, the output terminal of group selection signal switch unit 144 is connected with the input end of the second group selection unit 142 with the input end of the first group selection unit 141, the input end of the first group selection unit 141 is also connected with the output terminal of signal generation module 11, the output terminal of the first group selection unit 141 and M the first metal wire group 121, 122 ... 12M connects, the input end of the second group selection unit 142 also with M the first metal wire group 121, 122 ... 12M connects.
Group selection signal generation unit 140 is for generating group selection signal.Wherein, divide the length of group selection signal to be at least log
2m position.
The first group selection unit 141 is for selecting a first metal wire group according to group selection signal, and described first signal drives the first metal wire group of selecting.In other words, which metal wire group the first group selection unit 141 choice for use first signals drive.
The first metal wire group of the second group selection unit 142 for selecting to be driven by described first signal according to described group selection signal.In other words, the signal in which the first metal wire group is selected to accept in the second group selection unit 142.
Group switching signal generation unit 143 is for generating group switching signal.
Group selection signal switch unit 144, for according to group switching signal, is upgraded the group selection signal of output.Particularly, when group switching signal is effective, group selection signal switch unit 144 is upgraded group selection signal, and the group selection signal after upgrading is sent to the first group selection unit 141 and the second group selection unit 142; When group switching signal is invalid, group selection signal switch unit 144 keeps group selection signal constant.
Correspondingly, in Fig. 2, the grouping control module 14 in step 22 selects a first metal wire group to transmit first signal can comprise the steps: that group selection signal generation unit 140 generates group selection signal; The first group selection unit 141 and the second group selection unit 142 select a first metal wire group to transmit first signal according to group selection signal; Group switching signal generation unit 143 generation group switching signals; Group selection signal switch unit 144, according to group switching signal, is upgraded group selection signal.
Alternatively; as shown in Figure 3; for the present invention is for organizing the structural representation of switching signal generation unit in dynamic shielding protective device embodiment Fig. 1 of safety chip; in order once effectively to organize switching signal according to the generation of random time interval, group switching signal generation unit 143 can comprise that random number generates subelement 1431, compares subelement 1432 and group switching signal generation subelement 1433.Wherein, relatively the input end of subelement 1432 is connected with the output terminal that random number generates subelement 1431, and the input end that group switching signal generates subelement 1433 is connected with the output terminal that compares subelement 1432.
Random number generates subelement 1431 for generating a random number.Relatively subelement 1432 is for comparing random number and predetermined value.Group switching signal generates subelement 1433 for according to the comparative result generation group switching signal of subelement 1432 relatively.
Correspondingly, group switching signal generation unit 143 generation group switching signals can be adopted with the following method and be realized: random number generates subelement 1431 and generates a random number, and relatively subelement 1432 compares random number and predetermined value; Group switching signal generates subelement 1433 according to comparative result generation group switching signal.
This group switching signal generation unit 143 can randomization group switching signal interval effective time, like this can be so that the job order of the first metal wire group, working time randomization increase the difficulty of attacking and analyzing.For example: use 4 bit randomizers, as the linear feedback shift register of 4 bits, relatively this 4 bit random number and 4 bit constants 7 in real time; When the two is equal, output is group switching signal effectively, and interval effective time of group switching signal is random, and average probability is 1/16.If switching signal is effectively organized in output when 4 bit random numbers are less than constant 7, whenever 4 bit random numbers equal 0,1,2,3,4,5 or the effective group switching signal 302 of output in 6 o'clock, interval effective time of group switching signal is random, and average probability is 7/16.If switching signal is effectively organized in output when 4 bit random numbers are greater than constant 7, interval effective time of group switching signal is random, and average probability is 9/16.
Alternatively, in order to make first signal and secondary signal meet pre-provisioning request, for example: keep identical with the last cycle, signal anti-in last cycle, entirely zero, complete one, etc., grouping control module 14 can also comprise control module 145, is connected with signal generation module 11, for control signal generation module 11, generates first signal and the secondary signal that meets pre-provisioning request.Correspondingly, in schematic flow sheet shown in Fig. 2, can also comprise the steps: that signal generation module 11 is according to control signal, generate the first signal and the secondary signal that meet pre-provisioning request.
Alternatively, signal comparison module 15 can comprise signal comparing unit 151 and trigger element 152.
Finally it should be noted that: above embodiment is only unrestricted in order to technical scheme of the present invention to be described, although the present invention is had been described in detail with reference to preferred embodiment, those of ordinary skill in the art is to be understood that, can modify or be equal to replacement technical scheme of the present invention, and not depart from the spirit and scope of technical solution of the present invention.
Claims (10)
1. for a dynamic shielding protective device for safety chip, it is characterized in that, comprising:
Signal generation module, for generating first signal and secondary signal;
M the first metal wire group, is arranged in the top layer metallic layer of described safety chip, and each first metal wire group comprises N metal line, and wherein, M is more than or equal to 2 natural number, and N is more than or equal to 2 natural number;
A second metal wire group, comprises N metal line, is arranged in the intermediate metal layer of described safety chip, and described secondary signal is via described the second metal wire group transmission;
Grouping control module, for selecting a first metal wire group to transmit described first signal;
Signal comparison module, compares for the first signal to via described the first metal wire group transmission with via the secondary signal of described the second metal wire group transmission, triggers the safety precautions of described safety chip according to comparative result.
2. device according to claim 1, is characterized in that, described grouping control module comprises:
Group selection signal generation unit, for generating group selection signal;
The first group selection unit, for selecting a first metal wire group according to described group selection signal, described first signal drives the first metal wire group of selecting;
The second group selection unit, for the first metal wire group of selecting to be driven by described first signal according to described group selection signal;
Group switching signal generation unit, for generating group switching signal;
Group selection signal switch unit, input end is connected with described group selection signal switch unit with described group selection signal generation unit, output terminal is connected with described the second group selection unit with described the first group selection unit, for according to described group of switching signal, upgrades the group selection signal of output.
3. device according to claim 2, is characterized in that, described group of switching signal generation unit comprises:
Random number generates subelement, for generating a random number;
Compare subelement, for described random number and predetermined value are compared;
Group switching signal generates subelement, for generating described group of switching signal according to the described relatively comparative result of subelement.
4. device according to claim 2, is characterized in that, described grouping control module also comprises:
Control module, generates for controlling described signal generation module first signal and the secondary signal that meets pre-provisioning request.
5. device according to claim 1, is characterized in that, described first signal is identical with described secondary signal or meet predetermined condition;
Described signal comparison module comprises:
Signal comparing unit, compares for the first signal to via described the first metal wire group transmission with via the secondary signal of described the second metal wire group transmission;
Trigger element, is connected with described signal comparing unit, for when described first signal is identical with described secondary signal or meet predetermined condition, triggers the safety precautions of described safety chip.
6. the dynamic shielding guard method for safety chip, it is characterized in that, M the first metal wire group is arranged in the top layer metallic layer of described safety chip, a second metal wire group is arranged in the intermediate metal layer of described safety chip, each first metal wire group comprises N metal line, and described the second metal wire group comprises N metal line, wherein, M is more than or equal to 2 natural number, and N is more than or equal to 2 natural number;
Described method comprises:
Generate first signal and secondary signal;
Select a first metal wire group to transmit described first signal, described the second metal wire group is transmitted described secondary signal;
To the first signal via described the first metal wire group transmission with via the secondary signal of described the second metal wire group transmission, compare, according to comparative result, trigger the safety precautions of described safety chip.
7. method according to claim 6, is characterized in that, first metal wire group of described selection is transmitted described first signal and comprised:
Generate group selection signal;
According to described group selection signal, select a first metal wire group to transmit described first signal;
Generation group switching signal;
According to described group of switching signal, upgrade described group selection signal.
8. method according to claim 7, is characterized in that, described generation group switching signal comprises:
Generate a random number;
Described random number and predetermined value are compared;
According to comparative result, generate described group of switching signal.
9. method according to claim 6, is characterized in that, also comprises:
According to control signal, generate the first signal and the secondary signal that meet pre-provisioning request.
10. device according to claim 1, is characterized in that, described first signal is identical with described secondary signal or meet predetermined condition;
The described safety precautions that triggers described safety chip according to comparative result is specially: when described first signal is identical with described secondary signal or meet predetermined condition, trigger the safety precautions of described safety chip.
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| CN201310544799.6A CN103559459A (en) | 2013-11-06 | 2013-11-06 | Dynamic shielding protection device and method for safety chip |
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| CN201310544799.6A CN103559459A (en) | 2013-11-06 | 2013-11-06 | Dynamic shielding protection device and method for safety chip |
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Cited By (4)
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| CN103824005A (en) * | 2014-03-11 | 2014-05-28 | 东南大学 | Anti-copying system embedded with configurable IP core and anti-copying method |
| CN105447413A (en) * | 2015-11-13 | 2016-03-30 | 深圳市新国都支付技术有限公司 | Dynamic signal based security protection apparatus and method and POS machine |
| CN108701193A (en) * | 2016-02-12 | 2018-10-23 | 汉阳大学校产学协力团 | Secure semiconductor chip and its working method |
| CN110391187A (en) * | 2019-08-12 | 2019-10-29 | 兆讯恒达微电子技术(北京)有限公司 | A kind of attack protection protection structure of chip |
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Address after: 100195 Beijing, Yuquan, No. 23 Haidian District Road, building No. 4 Applicant after: KT MICRO, Inc. Address before: 100195 Beijing, Yuquan, No. 23 Haidian District Road, building No. 4 Applicant before: Beijing Kunteng electronic Limited by Share Ltd. Address after: 100195 Beijing, Yuquan, No. 23 Haidian District Road, building No. 4 Applicant after: Beijing Kunteng electronic Limited by Share Ltd. Address before: 100195 Beijing, Yuquan, No. 23 Haidian District Road, building No. 4 Applicant before: KT MICRO Inc. (BEIJING) |
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Application publication date: 20140205 |