Bitcoin Magazine

Build Your Own Hardware Wallet? Seedsigner + Satochip Combo is Nuts

Did you know you can build your own hardware wallet? I recently attended a workshop with Dani @bitcoineando, a Bitcoin evangelist and software engineer who will be hosting a workshop on just this topic next week in Adopting Bitcoin, El Salvador. The whole process took less than an hour and took me from having never assembled a small hardware device of this sort, to a fully configured and self-assembled Bitcoin Seedsigner and smart card backup combo via the Satochip suite. 

For those attending the now historic Adopting Bitcoin conference coming up this month in El Salvador, the free workshop will take place on Friday, November 14th at 3:50-4:50 pm, in the English Workshop room and will be delivered in both English and Spanish. Attendees who bring a laptop and go through the full workshop will get a free Seedsigner + Satochip combo to take home, plus the knowledge of how to build the whole thing themselves. Sign up here to lock in a limited spot now. 

What’s amazing about the combination of these two great open source projects is that they are made of very common hardware that can be purchased almost anywhere in the world. No specialized hardware from artisan manufacturers, this is a pure DIY project that can be a viable option for users in developing nations with tight import controls, under oppressive financial regimes, under a tight budget, or just those paranoid enough to want to build everything themselves. 

SeedSigner

The SeedSigner project launched in December 2020 and empowers users to build their own affordable, air-gapped Bitcoin transaction signing device for more or less $50 using off-the-shelf components like the Raspberry Pi Zero v1.3, a camera module to scan QR codes, and a small LCD display to verify transactions and navigate the menu with a small joystick and three buttons.

Created by a pseudonymous founder known simply as “SeedSigner,” today supported by a growing community of contributors and led by Kieth Mukai, the project emphasizes trustless private key generation and supports a wide range of toolin,g such as BIP39 seed phrase creation via dice rolls, seamless integration with multisig wallets like Sparrow, Specter, BlueWallet, and Nunchuk, among others. 

SeedSigner is fully Free and Open Source Software (FOSS) released under an MIT license for the core code. All hardware specs, software, and enclosure designs are publicly auditable on GitHub, allowing anyone to verify, modify, or build from source for maximum transparency and community-driven improvements.

While Raspberry Pi Zero’s CPU/GPU firmware and bootloader are proprietary and closed source software from Broadcom provided by the Raspberry Pi foundation, the design of the Seedsigner optimizes around managing those risks, such as letting the user provide their own entropy, and opting for no wireless communication modules like Bluetooth. Seedsigners are also “stateless”, designed to have no memory storage, instead booting fresh every time and requiring the user to input the seed that is used in the same session to sign transactions. 

These security measures make the SeedSigner a popular hardware device for enthusiasts and advanced users; however, it presents some unique user experience challenges. Critics and competitors of the SeedSigner argue that manually inputting 12-word seeds into the device via key input or by scanning QR codes of private key backups puts user funds at risk, as it exposes the key material to cameras, which are ubiquitous in today’s digital age. The process can also be tedious and presents a user experience friction that stateful hardware wallets do not have, which is what makes SeedSigner’s collaboration with Satochip smartcards so special. 

Satochip

Satochip, a Belgian startup founded in 2014 by Baudouin Collard and Bastien Taquet, focuses on affordable, open-source smartcard-centric hardware wallets. Their flagship products — Satochip (NFC hardware wallet), Satodime (bearer card), and Seedkeeper (a kind of password manager) — work with wallets like Sparrow and Electrum. Their Java Cards project is an open-source (AGPLv3) applet that turns cheap smartcards (e.g., YubiKey, SIMs) into secure, DIY BIP39 hardware wallets with EAL6+ security. 

Taking a different approach to crypto key security, smartcards are stateful and store key material in encrypted formats, using some of the most advanced security chips in the market, often better than the technology used by credit cards and bank debit cards. The smartcards are NFC-enabled, leveraging the same near field communication technology that much of the world is used to today. An antenna that, while ranged, is considered so limited in its distance that advanced hardware wallet manufacturers like CoinKite have also integrated it into their highest-grade hardware wallet, the Coldcard Q. 

The main downside of the smartcard approach to crypto security is the lack of a screen, which is needed for users to verify what they are signing. Satochip thus integrates with various mobile and desktop apps, as well as its own apps available on Android and iOS. 

SeedSigner, through a community member fork of the firmware, is also now deeply integrated with Satochip, allowing users to flash the new smartcards directly from the SeedSigner, improving the experience of setting up the wallet, while also supporting a smartcard reader hardware expansion. The Satochip integrated SeedSigner firmware was created by YTCryptoGuide and can be found on his GitHub. The fork is not an official SeedSigner release.

The combination of these two open source projects seems like a match made in heaven, as users can now leverage the open source, consumer hardware nature of the SeedSigner, with the seed backup and ease of use nature of the smartcards, arguably improving the security and user experience of both projects. 

One of the very valuable skills of the workshop, its corresponding website, and how-to guide teaches how to verify the authenticity of software installed on the hardware. Both the Seedsigner and Satochip applets are signed by the developers with their PGP keys. A hash or unique cryptographic ID of the software is created using an algorithm like SHA-256 (used also in Bitcoin mining) resulting in a string of digits, this string is unique to the exact software used to generate it — if one letter in the software is changed, the hash changes completely. 

That hash is then signed by the developers with their PGP keys, which produces another unique and deterministic blob of data. The result is a chain of software signatures that ultimately let users know a known and reputable developer is acknowledging a specific software release as legitimate and authentic. 

Knowing how to do this kind of verification can seem daunting at first, but it is actually quite easy and stands as the root of cypherpunk values and sovereignty in the digital age. 

This post Build Your Own Hardware Wallet? Seedsigner + Satochip Combo is Nuts first appeared on Bitcoin Magazine and is written by Juan Galt.

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Bitcoin Magazine

From Wallets to Signers: Ledger Nano Gen5 Advances Crypto and Identity Protection with NFC Passkeys

Ledger, the most popular cryptocurrency hardware wallet company and one of the oldest in the industry, just announced its latest, most advanced security device, the Ledger Nano Gen5. Taking the capabilities of previous Ledger devices to the next level, the Gen5 also reaches a surprisingly low price compared to its predecessors. 

Ledger has sold over “8 million devices in 165 countries, across over 10 languages, more than 100 financial institutions and commercial brands,” according to a press release shared with Bitcoin Magazine. The company claims “over 20% of the world’s crypto assets are secured by Ledger. “

Check out the livestream of the announcement live!

The Ledger Nano Gen5 is 79.40 mm tall, 53.35 mm wide, and 8.64 mm thick with a Ledger EAL 6+ certified secure element (ST33K1M5). Its E Ink®, black and white capacitive touch screen has a resolution of 2.76 inches, at 400 px by 300 px and 181 ppi. It weighs 46g and has USB-C, Bluetooth® 5.2, and NFC connectivity. 

The device comes with a “Ledger Recovery Key” included in the box, a high-security smart card designed to back up the 12-24 word pass phrase that users create on device setup. The Ledger Recovery Key connects to devices like the Gen5 via encrypted NFC, unlocking a new, easy-to-use seed backup device, which is pin-protected at rest. While the name of the Ledger Recovery Key is at first glance a bit confusing, the smart card should arrive empty on initial purchase and get loaded by the users during the hardware wallet setup, when they generate their pass phrase at home. 

Signers Rather Than Hardware Wallets

Ledger has also decided to rebrand their devices as signers rather than hardware wallets, a move that breaks over a decade of tradition within the crypto industry. The daring move reflects an industry shift towards securing more than cryptocurrency wealth — secure digital identity from “a world accelerated by artificial intelligence.” The rebrand also applies to their flagship software wallet, previously known as “Ledger Live”, now called Ledger Wallet. 

The subtle change in wording could address confusion new users may experience when entering the crypto industry, and perhaps aligns more closely with the functionality of these security devices and interfaces. However, how users respond remains to be seen. Ledger was clear that the Gen5 simply expands its security offering to the world of identity, while it “will continue to operate as millions now know them” to operate, when it comes to securing their crypto transactions. 

Protecting Your Digital Identity

When it comes to identity, the world is going through a transformation. No longer are physical ID cards good enough; multiple image generation models have shown sufficient quality to fool identity systems, while stolen identities from major data hacks are used regularly to commit identity fraud. The only viable solution to the problem of digital identity is strong cryptography, and Ledger clearly recognizes this growing trend.

In order to support secure identity and logging capabilities, the Gen5 and its Ledger Security Key cards support the FIDO2 Passkeys standard that is spreading throughout the web. NFC, which stands for near field communication, is a fairly secure short range antenna, used in credit cards for decades, this standard is also quickly being adopted by crypto hardware wallets for the same reasons, it is easy to use for things such as approving a log ing, while also providing a high degree of security, given its short range and simplicity.

Bluetooth is also integrated into the Gen5, giving the device a wider range of functionality. Bluetooth has also become a popular feature among hardware wallets and key signers, though it is a feature often criticized, given the vast complexity of its code and the long range at which it can be interacted with. Some hardware wallet devices even choose to skip Bluetooth altogether. While the press release did not explicitly address how the Gen5 secures users against the risks introduced by Bluetooth, the industry standard is to distrust the chip, separating it from other capabilities, and using it only for encrypted communications across devices. 

On the interface front, the Gen5 supports advanced security features like “Clear Signing” and “Transaction Check,” which its beautiful E Ink^® touchscreen likely delivers with a natural and intuitive feel. The press release further explains the new identity capabilities of the Gen5, noting that “users can now connect their Ledger signer directly to popular dapps, such as 1inch, for seamless and secure experiences,” adding that “Ledger is integrating Noah, known as Cash-To-Stablecoin, enabling users to top up their wallet with fiat (USD or EUR) quickly without additional fees, and instantly convert to stablecoins (USDC)” Noah enables the “effortless” use of stablecoins for on-chain transactions, another quickly growing trend. 

High End Tech at an Affordable Price

When it comes to price, the Ledger Nano Gen5 is far more affordable than its predecessors, while keeping the large touch screen that has defined the newer generations of Ledger devices. Coming at more than half the price of the Ledger Stax, the Gen5 costs $179, a very competitive and accessible price among modern crypto hardware wallets. 

Pascal Gauthier, Chairman and CEO of Ledger, proudly noted in the press release that “the all-new Ledger Nano is built for the challenges and opportunities of today, and ready for those coming in the future. It is the new signer for everyone, available at an accessible price, with the best security and user interface on the market. The next generation of Ledger begins today.”

This post From Wallets to Signers: Ledger Nano Gen5 Advances Crypto and Identity Protection with NFC Passkeys first appeared on Bitcoin Magazine and is written by Juan Galt.

Sometimes simple things require complex solutions. Today’s article is sponsored by Right Control key.

Funny situation… some time ago I bought another keyboard, this time Microsoft Designer Compact Keyboard.