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Comment by caf | Hacker News Reader

Those VISA/MasterCard rules can't be universal because there's at least one bank issuing merchant terminals that run Android and take the PIN on the touchscreen:

https://www.commbank.com.au/business/merchant-services/eftpo...

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Clover CEO here. Won't comment on a competing device but this may not work the way you think. In Clover's approach the touch controller input isn't reaching the Application Processor running Android when in PIN entry mode. You can do patent search if you're interested.

That would be in line with the requirements. You go through stringent certification with the software and hardware that has access to the actual PIN and then show that the application and application hardware never really has any access to it so that you can customize/update your software.

This is the easy part.

The hard part I remember was establishing secure communication between all components in the system (initializing HSMs, injecting keys). I remember helping designing the process and writing hundreds of documents describing various security-related procedures like how the HSM racks are inspected, how the keys to the racks are fetched from the safes, how there are multiple safes for multiple security officers, how the officers are prevented from ever having access to other safes, how fetching anything from safes requires logging and using tamper-evident containers, how the logs are inspected, and so on.

I have designed a special cryptographic protocol so that we could generate and inject keys to the devices in KIF (Key Injection Facility) and separately to our database (to establish communication with the terminal). Fun.

Agree the people and process side is very difficult to do well. Familiar with all those and more -- we have extremely good, dedicated employees who care deeply about doing those things right.

We have some fun stories on this topic, like when we were using our PCI PIN approved secure room in our development office for the first time. We papered over the cage to prevent a security camera from being able to see employees entering PINs on the HSM. An eager employee papered over this cage a little too well cutting off the natural flow of air. And then there was a bug in our offline CA code and we spent 30 minutes in that air deprived cage while debugging occured :) finally the bug was fixed, we issued the cert on our first production device, and stepped out to get a breath of fresh air. Obviously this isn't our daily driver secure CA room :)

(If anyone reading is looking for a job in security engineering, we're hiring! https://www.clover.com/careers/engineering)

I have few more stories like the time when I closed the HSM rack door a bit too energetically and caused outage to entire company as we had to bring in third security officer to re-initialize it.

We also had special screens created for all cameras in the datacenter to block view on the HSM racks.

The biggest issue was, just before end-to-end test we figured out we forgot one of critical procedures (it was establishing authenticity of the HSM used) and we had to scramble to get new HSM and to re-establish all cryptographic material (so new storage keys, etc.)

404

What you're describing sounds like another backdoor of its own!

The general problem with most "industry security" approaches is that they simplistically attempt to wrestle ultimate Godmode-control for themselves, rather than working towards eliminating it.

Those are universal PCI council rules the fact that the terminal runs android doesn't mean anything it still needs to be compliant with the PIN entry device requirements as well as PTS and POI requirements depending on the exact nature of the device:

https://www.pcisecuritystandards.org/documents/pos_ped_secur...

https://www.pcisecuritystandards.org/documents/PCI_PTS_POI_S...

The requirement for the tamper proofings is literally the first requirement in the PED standard:

A1 Vendors must comply with all components of A1.

A1.1

The PED uses tamper-detection and response mechanisms that cause the PED to become immediately inoperable and result in the automatic and immediate erasure of any secret information that may be stored in the PED, such that it becomes infeasible to recover the secret information. These mechanisms protect against physical penetration of the device by means of (but not limited to) drills, lasers, chemical solvents, opening covers, splitting the casing (seams), and using ventilation openings, and there is not any demonstrable way to disable or defeat the mechanism and insert a PIN-disclosing bug or gain access to secret information without requiring an attack potential of at least 25 per PED, exclusive of the IC card reader, for identification and initial exploitation as defined in Appendix B of the PCI POS PED DTRS

This only accept contact-less payment who doesn't require pincode.

PED/PTS devices have even stricter guidelines than contactless payments.

But this device doesn't need a way for the user to enter the pincode. So, all the sensitive part of the terminal is probably completely isolated from the android part.

I don't know this device internal and the PED/PTS exact requirement but it seems plausible for me.

You have something like a physical compartment who include the NFC and everything needed to process it like in a classical terminal. This compartment is highly secured as requested by the specification with just a very simple interface for the android part to send the amount to bill.

I've seen a lot of each-machine running on windows. Doesn't they work like this with the windows machine just managing the display buttons to select the amount and sending this information to the secure part who handle card interaction, pincode and delivery of the money ?

Yes this is a common design in fact most current solution segregated the POS and POI completely anything that handles the actual credit card whether it's C&P, Track2 or NFC is a closed black box with the required PED/PTS/POI and P2PE certifications the merchant never sees what's going on they only can talk to the thing in bill the next card X and get a confirmation of the transaction that's it they don't see any of the card data they don't even see any card holder data unless they collect it in a side channel e.g. a loyalty program.

Now none of these certifications or standards is bullet proof but people have a very skewed vision of the PCI certification process likely due to bias of only having interacting with the PCI-DSS requirements for merchants and low levels to boot meaning they didn't had to do anything but to fill the SAQ themselves and be on their way.

It accepts contactless payments over the threshold where a PIN is required, and does in fact prompt for a PIN using an on-screen keypad.

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