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>> Hello everybody. Yes and now then when from Vietnam. Today I'm going to present my research hardware to the new Texan using the box carrying side can. So I guess most of you when reading the title for the 1st time were like What the hell is the box carrying such an array because most of you might be familiar with chosen a site and I'll suggest and power sites and but there's a chance that you never heard of the box gathering site to know before so this is a very new physical side channel that we discover for our hardware turn detection and in the present day Sion are our talk about how we came up with that idea at the.

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Site and know how it works and how we use it for hardware to need to action. So this is the overview of my present patient 1st hour is some introduction and then I'll talk about the previous approach and then problem Steadman and then I'll talk about how we use the box carrying side channel for hardware so in the section and finally I conclude my present nation so what the hardware chosen why should we care what should we be concerned about hardware chosen the hardware Children's is the least certainly ficus and the chair of an integrated circuit.

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For years people used to believe that the hardware level is the root of just the only and just a part of the firmware and the software on top of the hardware right however with the emergence of hardware children. That assumption is not true anymore nowadays even the underlying hardware cannot reach us that because of a test like hardware chosen.

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So why pay why didn't people think of hardware children before and why have hardware chosen become such an increasing denser threat so there are a couple of reasons the 1st reason is that nowaday in Tikrit have become such an important part of our life we cannot do anything without using something that has a lead in secret a circuit in the right.

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We can see them in every electronic device like computers cell phone after lane rockets so answering nowaday answering the security and just far into the greatest is a very very important job However nowadays in t. going to get more and more complicated and the cost and time to market come to your essence have led as a vendor to outsource many many steps in the supply chain is and that's why I.

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Have become more and more vulnerable to hardware chillen attack why it's simple because there are too many entities involved in the i.c. making process that right because there are so many. Entities involved is very hard to end so the chance and the security security of the hardware is specially when foreign governments could be one of the possible adulteries that can inject hundreds of them to the chip and another reason is that the hardware chosen it's chimley difficult to detect hardware chosen especially when is Dollmann.

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Because of the following characteristic a part where chosen So a typical hardware children consist of 2 parts and the payload. And normally her right to them is very small and stay out of the Tom the only I keep it the only active part is a small cheap girl so that will keep checking for the right countries and to activate the payload.

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Of the hardware chosen however the. Rights of the normally got to go in via very rare conditions. Normally hardware chosen are inserted in the very hard to Concho and hard to reach reason of the chip. And wonder why so than get inserted in the chip and got the chip get 5 Rycote it cannot be removed a live wire software model where the software chosen right so it's a very crucial to be able to detect hardware chosen before selling the chip to cost them all before integrating the chip into your system so no more here I give an example.

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Shows an attack along the I see life cycle it can see that every step there possible to an attack and Income Income cruel than become more and more are denser earth because of 2 reasons The 1st reason is that now they are into growth could have become more and more vulnerable to heart chosen attacks and the 2nd reason is that it's difficult to detect armor hardware chosen.

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As I mentioned before. In the past people used to be really that the underlying hardware is just that not many so many hardware chosen detection techniques most of them fall into 2 categories. The. Reverse engineering and the nondestructive. The Texan approach. The destructive reverse engineering is has advantages that is very highly accurate however however is extremely expensive and time consuming and all the chips after get tests that will be destroyed so that's why this techniques are not very commonly used.

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Non-destructive hardware to the Nathan approach to can be divided further into 2 groups prefer approach and post to call an approach to solve the preceding approach focus on detecting hardware chosen. For example trying to detect abnormally in the south caught in the layout of the me for the chip get fabricated.

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This cheap and fast however the drawback is that they can only take hardware chosen that are inserted up the design this fog down though if hereto than are inserted at the foundry then the method cannot work the post physical approach can walk for any chosen incident at any stage it and they can be for the divide into a functional testing and cite an analysis so the Functional Testing relies on finding the right input vector for the chip and compare the output to the fact that most seem with it want to see if there is anything abnormal However as I mentioned before it chimley difficult to activate hardware chosen and if the hardware chosen is not activated it wouldn't change the output of the chip so the probably the existing hardware chosen for functional testing is extremely low and therefore most of the methods focus on site and the analysis and site and analyze it can be divided further into on chip measurement techniques and if there are no measurement techniques for the on chip measurement techniques people ask some obvious in the circuitry inside the chip for measurements and the advantage is that because the measurements of good cheese is inside the chip the sight and no signal is green and strong the drawback is that the obvious in the circuitry will let the overhead to the performance area of the chip so that's why this is also not very commonly used.

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Finally the it's a no measurement techniques so this is it doesn't require any ideas in the cheese and they rely on measuring the sights and of from outside the chip so this is a most widely used horizon and it isn't technics and in this present there's an I will mostly focus on the Gnome as I'm in technique so.

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To get more into detail about the experiment so no measurement techniques the general measurement technique to rely on measuring sight on the signal from outside of the chip and the app some very commonly factor no such a power. And temperature side channel and x. of the site and it has its own drawback the power factor nor has a very limited.

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Very low bandwidth because there aren't cheap capacitance act at the low pass to those so because the. Low is very hard to detect small and past the chosen. E.m. fact Arnold is also very in the response of the current various on the inside the chip and the signal to NY ratio.

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Is really affected my knowledge and interference so it's possible that the knife will cloud the chance cos my happier children in the psychoanalytic know what's prevented from. Being able to detect a small children's finally the temperature psychoanalysts. Vestal low in time with Pam and it's over have a roommate the man with by analyzing the previous site I know we came when we came up with the conclusion that the existing fact is insufficient for hardware to need Texan so our research goal is to develop a novel fact and sit by the hardware to learn the Texan technique.

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We have an arson that we can use the existing psychoanalysts power temperature and we try to improve the technic so it can improve the detection performance however how no matter how fancy the technique is it cannot resolve the drawback of the title itself right so that's why we introduce a new physical fact channels such as called the box carrying site and no work has been with impudent awareness and my residence and we properly multiple hardware to and it isn't technically that ill's is this site I know and we prove that they walked well and what better than other sites annals.

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In the in the next x. an hour will talk about how we came up with the idea of the box getting site Ana and the concept of the last icon now and how it works so the box Muskerry actually is not a very new concept Act actually back going has been ill by the company case and for years fuck them over here is an.

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Example of a t.v. core I have id communication we have and I have an idea Rita. It has a chance to mirror the chance of a continue. To what I've already tacked and that I detect has. Chipped that can switch to impedance that this hero and the one and the impedance switching will change the reflex and go Thiessen of the of the task and as a result it will change it will model as a signal that is reflected mocked.

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Rita so that muzzling the signal will carry the informers and back to the reader. So by analyzing the mechanism. Of id communication we came up with the idea of the box carrying fire terminal and hypothesis that the box carrying radio if folks be prevented Ditto electronic device of all why because chances in digital circuits are so cancerous between 2 impedance this just similar to the idea that the chip in the I need.

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And because the 2 is that of the open and close. Chances that I will have different impedance. Impedance which. Reflects an coefficient of the chip as a soaker and as a result it will model it a signal that Iraq's. Just similar to the IP communication and it back there are sick no information about the chip like how the impedance to it and impedance switching inside the chip so that the hypothesis it have a test and the concept of my scoring sites are now is that fuck them away have a set up grandfather we have 9 get here then then get cancer it's going to.

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Test one and 0. We have the. Resident. And then get s. follow for one bad and 0 is have 2 different impedance so similar to the op id the chip in the eye of id tag. And. Continuous way to work the set of this set of 9 gears.

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Switching activity will cause the impedance chains change from 0 and $1.00 and the boxcars the boxcar signal chains at the get chains that. And they create an impedance based site and know and we call this the boxcar in fact I know and this site on a will carry information about the switching activity of the gates and this is a very very different from the current flows by sight and e.m. and powers Tatiana and that will prove it in the concept of this fire channel and prove that it's much better than Al outside channel in our water need section so to prove the concept of the box carrying side can know we implemented a linear fit Maxi presence on Epi ga.

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The reason why we chose the linear feet back sit resistor because. It's very similar resin is a basic element of the solos equipped clock driven and rather have to impedance that and a chain of resist switching will more a war Embley 5 the effect up one resists the switch so that's why we chose linear feedback to present to prove the concept.

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Boxcar in fact channel and we implemented this circuit on Epi Ga and when the designs are just so that flip flop the chains will toggle between 0 and one at a frequency of m. and we so this talk will in this linear fit Max it rather worked the toggling frequency is f. m. and we call it toppling.

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An implement of the circuit an Epi a and with sinus I was African c.f. Kariya chance made the sinus our way to work the epi. And receive the boxcar signal to see if actually a any impedance switching in families and in the signal. So here is a theory mn set up we have an Epi ca here which we implemented the linear fit back to President on this episode and we have one chance to beat one chance he's a pro Pia we were champion of sinus I was to what the f.p.g.a. and the average of the ep is a is the running circles the taco between the frequency f m ag the sinus I wave will go inside the chip and it will interact with the chip circuitry and it will give a mascara reflect the mark and then we will have received a prop here we receive though mascaras signal and it connected to a specimen alive and my analyzing the boxcar signal will.

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Have information about the sub good. Switching activity so the idea is that if the back out signal actually Small's a little by the switching activity of the earth then if it comes in the fiber and components I carry my net and class m. f. carrier carry away that we transmit towards the f.p.g.a. and the f.m. is the Taco Ling frequency up circuit inside the f.p.g.a. so which was a carry a tree heard and we talk all in the frequency of the circuit from 400 to NY and roadkill are heard and we of the that Ok at a frequency f. m. with actually c.s.i. been here and when we change the frequency of talking a frequency of the circuit the read when we change from 400 to 605 and we move from far north 400 to 2nd route.

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But the. Central component of the carrier will stay the same so this mean that this might scare our signal actually has the information about the switching activity of the so good. And mean that the. Carriers and Formosa know about the impedance switching. So. Based on this we came up with the idea that the boxcar inside China will be very useful for detecting activities such as hardware chosen because you know that when hardware chosen is attached to the circuit even if it is not activated it would change the impudence of the so good anyway right because there's something a tech to the it will impede and will definitely be chains and because the boxcar inside John no b. is capable of be taking the impede in chains inside the circle then it will be very useful for.

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The new Texan and also the boxcar inside China has over a vent it. Has been with is a signal strength can be in improved and not limited by the. Device and frequency can be shipped to so we can avoid noise so told to delay the box carrying side to know is a walk the mare or b.m. and power down no and we prove it by experience and result so now we'll talk about how so the previous 6 and I talk about how we came up with the idea of the boxcar insight I know and how it works now talk about how it was a box carrying side channel for hardware so in detection.

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So the idea that. Every switching pattern followed the clock cycle right and the clock is really a come on at the switching the lace along an entire part of the law that. Therefore if there are some changes. Up some indeed is a guess the chance will be aka abruptly asked some pause at the clock cycle so the boxcar signal will content the sideband component of several How many of the clocks.

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Asked somehow more if you'll see some. Change in the cost as how much of the attack to the. Circuit so by Normally the because as I said before the change caused by her watch isn't often very small and fast so the change will aka abruptly as some part of the clock cycle so if we can measure the subgraph sample in the time domain of the blackout signal to definitely be able to detect hardware chosen however the tandem and signal is too noisy and too hot to attract So we instead look at the frequency domain and we look at multiple one make a clock in the frequency domain to up the chance in the subgraph samples to the to card where chosen so the idea that we use multiple clock home one make the amplitude of the clock are monic.

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And got harmonic we only measure the Amberley to fuck them but we measure like how many of the clocks of the circuit and the Emley 2 and then we from the m.d.t. of the crop circle at the everything ratio. And we have far more choices including ratio of all the clocks home on a cherry will characterize.

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Of all mouth pounding and us and impede and chains that follow the heart of how our children can be detected by 1st we call it. First with calling the changing from hardwired to and free I see and then how do I show the need eyes and can be performed on other boards by checking my colleague.

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Mark scaring sites and chase agone compared with the chaining to see if they add if 2 different from the chaining So fog them Ohia. We have implement implemented and a p.c. and way they have. Good clean. And hard water than in fact the circuit and we call it the boxcar chase the clean one and.

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Have Watson in fact that run and we see that a lot of the Chinese some parts some different. The black one is a. Green one and a red one is our chosen in fact that one and we see that at some point some clear difference. The problem is not along the Chinese the family 2 very very a.

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Significantly among the different a poet's So it's very difficult to see the difference. So we normalize the chased by to the mean. Then Ewing chase and we can see the difference clearly. And you can see here there's the black one is. The clean the chase and the red one is the chosen in fact the chase and you can see that some part of a longer chase there are some different caused by Cho than activities.

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And this is so that we can actually detect her watcher than by just underlines our mock scoring sites and. Signal. So this is an algorithm we have changing changing face with basically we're only we call it the no and formal motto of clean good. Clean chip and then in the testing phase we test on multiple other chips to see to compare them with the.

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Chaining model to see if they are 2 different difficult different from the chaining model to. Come closer than that or whether it's chosen in fact that. Is clean one so we use the same elements set up and we actually implemented 3 different chosen benchmarks from. Cho than have different.

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Functionality and trigger mechanism so we implement all those chosen on f.p.g.a.. So the challenge we face when we implemented chosen is that our children is a modification to the south. So if we modify the code and we. Come power and claim and routing again father. Then it moved.

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The change caused by chosen we. Will called to change the placement in routing of the most of the laws the elements of the. It will. Detect an apartheid so than very very easy because not only their chosen other part of the chip got reroute and replay mn as well so that different will be very clearly so we cannot mean that we.

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Not modify the code to insert hardware chosen So the question is that how we can insert hardware chosen into the clean circuit without changing it without changing its such code so that follows any of that we just come power and do placement and routing far wiser than in fact that and then we see c o 2 we remove all the chosen logics from the chosen in practice circle to create the chosen clean one.

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For example the right one is chosen in fact that one it has chosen length and with then we use the Ethiope 2 to remove all the children look took create a clean. Chaining was asked how we create Children Denmark. An. Apple having the band mouth would have to m.r. Lew it out techniques so the critic arterial fall good hardware too and it takes an scheme is that it has to be capable of detecting Dolman hardware chosen and it has to be Rob out to manufacturing variation among different hardware instance so the question for our technique is that is this.

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Is this such defies all of the 2 criteria in here. So that's why we focus on the detecting Dolman hardware chosen in cross training scenario the cross ending is that we chain on one ep easier bar and when testing we don't test on the mark with test on one and f.p.g.a. both so we would take into account the manufacturing virus and among different hardware instance so far as opposed.

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To detect hard on one hardware chosen even across the chaining scenario where we have far different test subjects the 1st one is a are in. And 3 different hardware chosen. Design and chosen design have different size as some write in the table so when we do training we call a Tandy Masm one on one mark for the r. is a no clean a good and then x where the money will be used for chaining in isolation and when doing the detection we met a.

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Test of the Fall For example we have Paul test subject Rifaat a test of the we measure time it hands on x. of the NY barks so. Far as of the test of the. So in total we will have to make a route we had to make $700.00 and turn a nice isn't an hour as I'm a solo that.

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100 percent accuracy with neuro Pol Poth holiday for all the chosen new life in the training scenario. Now because the postponements of our them is very good we will focus on changing paramita to see what affect our performance takes and performance of us on the detection of the dominant hardware chosen versus the detection of the activated the hardware children's So it's very intuitive.

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It's intuitive that. Activate how our children will be easier to detect than the dom or how our children's because when the chosen is activated. Both the cheetah and up a large chunk of narrative will be active but when it stayed on one of only the small so Kaci of the to be activated so intuitively it's much easier to detect the activated her watcher and then the dom on her chosen so in the experiment we want to prove that by comparing how we detect hardware children what's the activated and how do our children work the downturn so we're the same set up and we use the same algorithm for the.

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Activated and Dolman hardware chosen and here as a result. You can see that. The red one is the dominant hardware chosen. And. The other one is. Activated her watchers and you can see that the devious and from the from the. Green circle it's not a lot of fraud activated chosen than the Dom and chosen so far most of cos would can give 100 percent accuracy with 0 false positives but if it's show that it must easier to detect.

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Activated hardware show than than take Dahmer hardware chosen and down $110.00 it's normally very difficult to me to take that that's why it's very challenging to detect hardware chosen and most of the preverb techniques they focus on detect. Far focus on detecting activism chosen only in our results we focus on detecting Dom and how I chose and which is much too difficult to do and they were gave a 100 percent accuracy with their 0 false positive and now we will have another like how the cheater end up a lot that effect the detection performance so a typical hardwired to than had to park right trigger and pay a lot and when the children stay dominant only that is activated the palest stay down and so it's very intuitive that the Chivo will when we try to detect Naaman who are chosen the true true will play a more important role in detection performance than the payout is though and to in order to prove that we do the following it's theory Mn.

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We read is a society chosen higher tolls and cheaper and paid out individually. So 1st with radios are fire the cheetah girls. Here we have the tests up like that you go outside reveals farm 0 part 10 to 7 to 0.0 s. keep in mind that there are part time is 7 it's actually a very very small psyop so ready.

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This is the result. We can see that at the. Size reduce the difference between the chosen in fact a circle and. Gets reduced from the red one to the. Green one and when the sing in to like 0.08 percent of the circle it totally Motu the green circle work to mean that we cannot detect them anymore so they prove that our children.

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Have great impact significant impact on the right and the Texan and this I'll see cope we can see that. Father father children with poor. And far chosen with half of the true outside we can still take them with 100 percent accuracy but when the chief get into 011 point falls are in a sign we cannot take them with perfect curacy anymore so that this now is currently the limitation of our technique.

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And when. Next mood do it's women which in the pale. Would do the same process of when we change the cheetah we also we keep the chigger the same now which in the pale. And as we can see we were and which in the pale it doesn't really impact the performance of our rhythm is.

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Because when we detect that on one hardware chosen the payload doesn't do anything it's just a domino only the stay active it activated so no wonder how the 5 played out is as long as we have the surface in sire we can still take the white chosen. And we do another experiment for changing the poison of the chief.

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Of the. Chosen. We have 3 different we have the are in OAS are good and we change the style. And the payload are chosen from cause and one to the person to 2 and 3 from one to 3 is go further away from the circle and is also again is very intuitive.

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That when the chief is when the chosen to go further away it is easier to be detected because when you go further away it in order to be connected to the are no so it will net it will need along a wire interconnect to connect to the circle so it will impede in chains.

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As a result is who. Be easier to detect than that if for the away from the circle. An hour is supreme and so that when which. Politan it also has significant impact on the horizon and the Texan but when we change the payload it doesn't have any. Impact on the detection perform an adult so the so the previous Texan we.

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Prove that Ok our Texan technique is doing the boxcar inside and no actually work very well for the taking hardware chosen but does it work better than the e.-m. and power factor no. Why should we care about using a new site or know if. It doesn't work better than a building site and a right so the question is that does it work better than chose to use an o.e.m. and powerless I can No Well the answer is how you are with a we prove that my experience.

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We. Actually use the same experiment set up and we can measure we call at the site on our signal for the m. Powell and mask our signal follow the same chosen design for example here we have traded different types of likely sites and we collect them and power and the box signal of all of them and then with the same Azarias them.

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In the way falls up for the palace such an away. The power problem. Worked very well and this is a result. My scoring side can know as I can see that for both Dom one and activated the hardware chosen they are different. From the chosen in fact that the.

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2 of the clean Chase was to mean that we can easily detect them with the box carrying side channel but with e.m.c. channel as you can see far activated of our children we can somehow see some difference but for the dom $100.00 are chosen the. Mode to the.

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2 is a clean circle which to me in that is. Most is. That touch and that we cannot take hardware chosen with the I am side panel and the power center while a power such an o. even get worse and there is a comparison to our c. code a.

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Technique when using boxcar inside channel and power side or no and E.M.'s I can know with the bass going side channel we can. Take all the children with 100 percent accuracy and hostility but father I am in the power even the activated I heartily and we cannot even detect them with 100 percent accuracy.

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And the fossils are they so they prove that the. Box going side and better than I am and powerless I can know so. Now I talk about another application which is using the box going side and always is Dixon of color fit as he is in the bus carrying site and no.

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Further count the counterfeit I see the counterfeits I see is the. Is the I see that's an outer I. Mean the. Program is we pro deal with our home isn't all of the ills I see to sow us a new one so it's very important to detect a counterfeit because at the report of the last 2 years.

[00:41:18]
Out of his ass he calls the company like $100000000.00 per year so we prove that by using the bus carrying such an eye we can. Take counterfeit I.C.'s Well we implemented different I.C.'s counterfeit I.C.'s and we use the same id 6 and messed up and there is also that we can to take all the car off it I say with 100 percent accuracy.

[00:41:50]
To come my present ocean. In that while we introduce a new physical factor no totally new physical factor No the box carrying side channels that works better than existing fact channels and we prop old new technics being the new factor for anything hardware chosen and the results so that our technique works better than exceeding technics the backfiring site and read on the in the power is high time no.

[00:42:24]
Yeah. That's the end of my free and Basin. Do you have any questions yet. So yes of that's what we are trying to. So it's really our next. Next publication we are so you know most in learning to scan the last number of chips like one and we have results 100 of them and we mostly learning to glasses classify them.

[00:43:24]
So my can of them is that like scaring me that it will be able to detect the chains in the hardware so I I I believe that can be applicable to the higher level but we would never try to test and. So we but I think that if it can be a couple of people to the.

[00:43:57]
So the one we implemented is the way we get the children from the chart topping mark so that is the most popular then math for hardware children research so I think that's the most realistic one already. So is. Yes So I actually if contributors and multiple authors farm or other water.

[00:44:28]
But we never we never test on something actually really use in reality the fact symbol the one that it was in the Iranian nuclear system we would never use. Yeah. Yeah I think there are parts possible but that's the reason why we have the training training we. Model that has all possible chance for imputing 10 years and then the testing will take any like abnormal that we've never seen the chaining before but.

[00:45:35]
In the other question. In the present I only present 3 of them but actually we we blame in the late night. On 3 different and they're not so good not only a yes but we blame it on different in so good as well. Too that different other than different shows and as well like around.

[00:46:19]
That we did so. For the crotch ending for example we we have parties and tests of ideas and then we have now different or. We measure 10. So. In Concord than far as children we have 700 and turned the test for a chosen and it gave birth to 100 percent accuracy.

[00:46:49]
But what. Does it answer the question yeah yeah yeah. So. Why. So far now our technique is only capable of. Telling that Ok there's something wrong. That that's what we're trying to move forward. So it depends how how how different. So if the. They are very disciplined then this is likely that there will be false positives but most of the time the dissent is not that that he would even our if we men we pull out of that Ok we're going tore at the difference in this walkway only a tad and I watched But you know now that we even had on $100.00 bar and we can't even tar at the various And so it actually depends on how the how he was different but.

[00:48:43]
I think normally it's not that he was and then I thing this technique can power it though different. So our technique doesn't require any are they our. So. Yeah I think that's a good idea but for now we don't have any reserve. Our. In fact this is as physically added to the.

[00:50:22]
Tree. A no no no no it's just the the signals go into the circuit and the switching in the so good. Muzzle is a signal that is a basket of back to the receiver so it is something already like the chip is activity so if we don't create any.

[00:50:52]
Which would run so good and then. Yeah so now we have to have something come to be compared to but we are developing a new technique that we can do modeling the new model that we do modeling models are so good and then we compared with the so good.

[00:51:17]
Models so that we don't have to have something that. So. For example a yes or good. It can one of the possible is that it will look at the sequence of the input when it's the best of it's one of the input it will activate their chosen active in the pill and the payload can know if Hanson like it Warlick the key of the circuit to.

[00:51:58]
Cover site. And use pin for example that one of the children that we see the main mark. Yes. The cell phone now we or only we don't we don't have to. Compare the output of the chip with. That's. Similar You know so you know we we do have an input but it's very simple spray that it makes sure that the chains in we we don't use that we're exactly one input when we run the chip we have to change.

[00:52:52]
The input from a one to another so we make sure that there's something chain in the chip activity from cycle to cycle so we can be able to detect which are. Also. You know that's a good idea we only. We only test on different. Chip. We didn't test on different facility for example for one.

[00:53:42]
Chip test on the other good idea I think we would do that in the future but for now we didn't do it. You know which was the. Same chip we don't care where they are from which is by buy them and then we test it on the year so you know it is a good idea to I think is a good idea to characterize based on the facility for the fall very I think it's going to be done in the future.

[00:54:33]
So for now the. So far now. Is a very big cover almost the entire chip so it doesn't change that much but when we are developing a new probe using new product that it must Malo then different Pozen can be different performance. Any other question. Thank you very much.