Topic: 5$ DIY Bitcoin wallet : pitrezor (Read 228 times)

The pi has a hardware number generator

About the cost, like Aura mentioned, most of the components are probably already lying around (wire, usb cable, sd card,..) or cost almost nothing (like the buttons). You can even make a box from recycled cardboard if you want to save a couple of bucks!

Security is a big topic. In term of trust, to reply to birtart, I think the product is equal to trezor. I use the same code as trezor with a slight modification. Both code, original trezor and mine are open source so open the the eyes of anybody. Both image, mine and original trezor can be easily recreated from scratch (recompiled) just by installing docker and running a script. So if you don't trust my download or trezor firmware you can build it yourself and examine the build process. In term of hardware, both trezor and pi zero are made of standard of-the-shelf components. The pi zero and trezor schematics are both available for examination. And since they both use standard components, they are both sensible to possible back door or bug that could made from manufacturers.

The main difference about security is the security of the flash memory. For the trezor, it is very complicated (not impossible ) to dump the flash and get the privates key and seed. On pitrezor, this is relatively easy because it is on the sdcard. But, if you protect physically your sdcard and use a pass phrase you are in good position because the pass phrase is never stored on the sd card.

Compared to the price of the trezor I think this could represent a good alternative for somebody who do bitcoin transaction occasionally and don't want to pay for a real trezor hardware. You have to take some precaution when you store the device or at least the sd card (in a safe place). This is more user friendly than going back to paper wallet and cold storage. For somebody that perform a lot of transaction and/or carry the device everywhere with him, the real thing is probably better.

I don't know what your salary is, but this project can easily be done in a couple of hours and it's probably more fun than your office job. The only time-consuming step is the soldering and maybe the downloading. But all the other steps are equal to setting up a brand new trezor wallet, so that doesn't really count. Also most components except for the Pi itself are produced in 3rd world countries, so that shouldn't be really much of a problem. I don't think that the shipping for a brand new Trezor is less costly than that of a Pi Zero.

I get what you're trying to say. What I meant that this isn't just worth the time if you're doing this just to save money(in my opinion). I'd definitely want to work on this just for fun whenever I get free time as it's fun trying other things out, but as a person in a 3rd world country? The shipping fees are going to be a pain in the ass to order those parts. Nope.

You should make something yourself, it gives you a way more satisfied feeling than just buying things. Also it doesn't require that much effort, as yheneaul created an easy step-to-step guide. Parts can all be ordered on Ebay, not really a time-consuming thing if you ask me.

Too much effort to purchase all the parts and set it up just to save quite a small amount for a Trezor device in my opinion. Though this should be a cool good project for the raspberry pi developers and enthusiasts out there.

You should've copied the exact words he said:
Besides that, anybody that has a phone also has a micro-usb to usb cable, so that doesn't really add up to the costs.
Buttons cost a fee cents, an HDMI adapter can be bought on Ebay for less than $2.
The only real costs are the Pi and the SD card, but some might have a spare one lying around.
That's not going to be $30, even if you buy a high quality SD card.

Hi yheneaul,
it's really impressive that you were able to do this development.
On the other hand, (and sorry to say, but) I would never trust any solution that's not the original, and it's not coming from the manufacturer's webshop directly, and that's a pity for amazon and ebay and for the others.... (but that's just me)
Wallets are the security storages of the coins (OK, I know they're only store the private keys), so if I have to deal with secure stuff, I'll buy the original.
What is the reason people buy Trezor, Ledger Nano S, and others? Because they want to use them, not only to store their coins. Hardware wallets are for people who spend some coins sometime and not only gathers them. For those who don't want to spend, paper wallet is a way cheaper solution (cheaper than $5 maybe). Hardware wallets need to have the screen and the buttons to let the users control their spendings, so your solution can be the competitor of the paper wallets, maybe.

The title says 5$ but that's the price of the raspberry pi.

And then it starts piling up:
An SD card.
A good micro-usb to usb cable.
A mini HDMI male to HDMI female adapter
Two push buttons (normally open contact, SPST)
An OLED display. In my case I used an SH1106 I2C .
Optionally, a box or enclosure for a more professional look.

Just the display is 12$.
In the end you end up with at least 30$, a lot of work, a higher chance to mess things up and for what...

It is indeed an interesting project but I doubt anybody would cheapen on 30$ but will store 1 BTC on it

Thanks for your job! But i think trezor is not software security, It's had hardware for security
Do you think so?

Hi Bitcoin fans!

I ported the code of the Bitcoin trezor wallet to Linux to be able to run it on a raspberry pi zero. The raspberry pi zero is a very popular, small and cheap computer that is available for approximately 5$. The choice of the pi zero is interesting because it can be used as a usb device when plugged on a host computer.

This allow anybody to build its own hardware wallet at a very low cost with a good level security if used with a pass phrase.

All the instructions to build it are on my blog here:

https://www.pitrezor.com

On my site I explain how to assemble the buttons like the real trezor and connect an oled display. The oled is optional because I also support the hdmi output of the pi zero directly.

The software image is ready to download and flash on an SD Card. The Linux image is based on Yocto which allowed me to build a very minimal Linux system with only the bare minimum softwares to run my application. All code modifications are public and the software image can easily be rebuild (with docker).

Yannick