Progress report:
Okay so I have been reading the technical datasheet/manual on the basiccard website.

I have found the following:
- Communication standard should be T1 - faster, newer and less error prone than T0.
- 200-400 lines of basic code will be able to run on a 2kb basiccard (0.9-1EUR).
- Files/directories can be locked completely or assigned a pub key you must communicate by.
- The card may be locked into a RUN state in which it can no longer be read or re-programmed. This would be the product the users get,
   so that a corrupted/thief terminal does not wipe/re-program the card or steal your keys.

Additionally ZeitControl, the company behind the cards, is a member of the ISO 7816 committee since 1996? so they are quite big, proven and respected.

In light of this I am buying the SDK and going forward with these cards.

Hopefully the basiccard "enhanced basiccard ZC3.12" card with 2kb EEPROM will prove adequate as they are very cheap - I think the cheapest on the WORLD market.

Hello,

I have not fully understand the scope of what you are trying to do (and too much to read as well), but you seem to be mostly on the starting into the smart card world.

I don't know if this relates to what you do or not: https://bt.irlbtc.com/view/94119.0

Current status: integrating it with Electrum for a sensible GUI. The card itself works for what I believe is sufficient functionality to keep a wallet.

And thanks for the interest.

Yeah I'm just starting out alright, still I can see the path ahead.

What you are doing seems very similar though focused on securing the computer wallet.
I can see you chose the JavaCard; with dropping hardware prices that's probably a good choice too.

I would love to share notes, that you have come so far already is impressive - I myself usually work slower.

Do you sign transactions on the card or do you only store information on the card?

If its the second, how do you prevent keys leaving the card and getting used by someone else?

I will keep it in mind. Currently I mostly need help to develop, which money won't help a great deal with.

Also I am still not entirely sure what I am trying to do is possible so I don't want to owe people money yet!


Progress report:
I have looked into Bitcoin a bit more and what my cards need to do.
It seems ECDSA is used to sign and what is signed is a SHA256 hash of the transaction data/tx.

Both of these algorithms are unfortunately a bit heavy computationally for a smartcard - simply programming them could use up a lot of/all EEPROM.
Hence some co-processing will likely be needed - I still have to research more on what my exact options are there.

Further I have found that the card needs to store a reference to any transaction it wants to spend as this is required info in a tx.
This will not be a major problem as most of these txs will be generated from the card itself and only a few will be "refills" that may be relayed to the card by a merchants terminal.

Fraudulent data from a terminal to the card can at worst only lead to having to pay twice and some unintentional doublespends by the user - security is still fine.

It will still be a no-trust security model.

I have also received the SDK which is very slick and all, I will share it with you guys when/if possible.

Next is finding out the exact card specifications needed (16EEPROM? ECDSA/sha coprocessor?) and what to program. If an algorithm is not supported I can program it, but this is CPU? expensive and a bit time consuming.

ZeitControl sells many different cards, some with different coprocessors and some with lots of EEPROM for custom implementations of unsupported things.

How much do you pay for your cards?

I think I will have to pay 3.8$/piece in order to get the crypto functions I need. (ZC5.4 card - 16 kbyte, SHA256 and EC-211 on co-proc).

The EC I could probably do, but the SHA seems to take a lot of code to implement and the price-step lower is a card with 16kbyte to implement both algos + BTC program. (16kb basiccard = 2400 code lines)

Nope completely new to this. I might be interested in your package - I will just look through what I already bought first though.

Would your package include your card code so I can steal/port it XD? I am planning to make mine open source.

Yeah, but the cheaper cards allow quite few lines of code and SHA256 is the problem. ZC 5.4 is the one I think.

I was probably going to port algos from some example project if I did that, but yeah I hope it can be avoided.

They are.

According to the producer they cost 1/3 of javacards/multiOS cards.

They use a version the Basic language which is DOS like.

The cards run near-byte code at the hardware level which supposedly means they require less EEPROM than javacards etc. (hence the price difference).
I don't know to what extent this is all true, but they SEEM cheap when I compare them to other cards on the net.

A comprehensive manual/datasheet/Basic language tutorial is free for download on their site - the SDK just lets you have a cybermouse and some cards on top of all that otherwise free stuff.

They also provide you with a free IDE that lets you test/step-debug smart card programs and program your cards - example programs are included.

Anything else just ask.

Right guys sorry I dropped off the map for a while. I became a dad and pursued some other projects (waste of time mostly), I also got a job as a real software developer. Nifty stuff.

Anyway I do have some progress to report and this is still my main and only hobby project.

Not really, the basic language is one the first languages and probably C like in performance. Further the whole basic card has been built around it so the instructions are almost hardware level from the get go.

.. and of course assembly is horrible to code, I don't think anyone uses it.

My main focus right now is a card talking to an android phone - even that is very advanced and android phones are more universal than the universal readers of one company.

Yeah I found out.

The EC-211 is just Elliptic Curve crypto over a integer field 211 bits large. It COULD likely have done secp256k1, which itself is just a variation of normal EC, but unfortunately their EC-211 does not use the normal EC curve.

y^2 + XY = x^3 + ax + b instead of y^2= x^3 + ax + b
secp256k1 is just specific values for "a" and "b"

This means the EC-k1 must be ported/implemented from some library - SHA256 is on-card. I still need to read more about pure BTC as I have been mostly reading about the cards and just EC.

I can't link to it directly, but is under "free download" on their english site: http://www.basiccard.com/.


Right now I'm looking into the T1 protocol, the basiccard terminal program from ZC will do it for you automatically, BUT it runs on a PC, not Android. After a quick look I doubt I could do T1 from the bottom, but other options such as reverse engineering the ZC terminal, contacting the company or finding a T1/DS1 library exist.

Thats all for now.

Another month, but I have meaty progress and good news to report!

The link at the end I ask you to download and share, it contains the source code, my research and progress so far. It has everything you need to get started etc etc..
(You wouldn't want the FBI to shut this down now would you!?)

What I have done so far is familiarize myself with the ZeitControl IDE and I have programmed some key commands and key/address pairs into the card-program. I still have to work out some kinks with correct command definition as their book has a really crappy way of showing syntax (no examples!  ).

I have started to program every day on my commute so I think step 1 of my plan could be done in a week or two. (Step 1 was making the terminal and card exchange addresses).

Quick guide to ZC IDE:
1. To add a file you first create and save it. Then you include it and rebuild. Only then its will show up as part of your project.
2. Under "help" and then Example projects->"Calc" you can easily access examples of basiccard code.


Now as for the good news: It seems ZeitControl does in fact have a Java library. As you may know Android is mostly straight normal Java and so this could mean putting the terminal program on Android phones could be very easy. The only major problem left is to figure out USB standards. (Android expects an out-going USB connection but the smart card reader is in-going, USB is a one way host->child standard as far as I can tell. Basically both reader and Android are normally "child")

Link:
http://www.4shared.com/zip/HdI942A-/BitcoinCardProject.html