When online devices are fully surveilled by cloud-based AI tools, air-gapped encryption becomes essential for protecting privacy and security.
This release introduces the new KEF encryption format and the powerful tools it enables.
Changes
Extended Encryption Options
The KEF encryption format now supports two new modes: CTR and GCM (now the default). KEF can conceal data of arbitrary length. This enhancement enables secure handling of passphrases, wallet descriptors, PSBTs, addresses, and other sensitive information.
Datum Tool
A new advanced utility for working with files, QR codes, and manual text input. It supports:
- Conversion between binary and common string encodings
- Encryption/decryption of KEF envelopes
- Exporting contents to QR or SD
2x Faster TC Flash Hash and Key Stretching
SHA-256 and PBKDF2-HMAC now use hardware-accelerated hashing, doubling the speed of TC Flash Hash tampering detection tool, encryption, and decryption.
SD Card Airgapped Firmware Upgrade Optimizations
- Verifies firmware signature authenticity before prompting for update
- Ensures only compatible firmware can be installed
- Displays the firmware version being installed for confirmation
- Hardware-accelerated SHA-256 hashing and other optimizations speed up checks
Support for "Old" Multisig Policies and Scripts
We added support for BIP45 (Legacy multisig P2SH) and complete BIP48 (Nested-Segwit P2SH-P2WSH).
Button Turbo
Hold the NEXT or PREVIOUS button to move faster through menus and other keypads (Tinyseed, Stackbit, Mnemonic Editor, Show Datum).
'New Mnemonic' Menu Disabled with 'Hide Mnemonic'
When 'Hide Mnemonic' setting is enabled, the 'New Mnemonic' menu is automatically disabled.
Improved Text Highlighting
Wallet fingerprint, network, keypad titles, settings categories, and prefix texts are now highlighted across all screens.
Enhanced Settings Category Colors
Boolean settings (True/False) are now displayed with color (Green/Red) for improved visibility.
Enhanced Address Verification
To facilitate comparison, addresses are displayed in space-separated groups of 4 characters with alternating colors.
Export Wallet Addresses
Export receive or change addresses to a CSV file on the SD card.
New CNC Printer Support and Fixes (OpenBuilds GRBL 1.1)
- Fixed CNC/FilePrinter compatibility with optimized QR codes from v24.03.0
- Introduced CNC/GRBLPrinter for direct serial printing to CNC machines
- Added support to choose between router/laser head engravers
Export QR Codes as SVG
Exported QR codes can now be saved as SVG images.
Improved Tests
- Code coverage: 10,000+ lines (96%) with 680+ tests, improving stability and reliability
- Added in-device tests focusing on hardware-accelerated features in Tools
Other Bug Fixes and Improvements
- Numbers are no longer printed as words in Backup Mnemonic > Other formats > Numbers
- Expanded keypad touch area to screen edges
- Tools > Print Test QR now asks for confirmation before printing
- Tools > Check SD Card now allows deleting files
- Load mnemonic > Via Manual Input > Word Numbers now shows the double mnemonic indicator (*) if applicable
- Added fingerprint to mnemonic preview and editor
- Fingerprint preview shown when changing wallet passphrase
- Passphrase and key entry now display length to reduce mistakes
- Saving encrypted mnemonic prompts to use fingerprint as ID
- Optimized board value checks
- Ellipsis now use a single character to save space
- Added QR code to About screen
- Fixed camera zoom mode clearing the QR progress bar
- Fixed camera rotation when orientation settings changed on Yahboom and WonderMV (now without requiring reboot)
- Theme restart prompt appears only when changes are made
- Wallet Descriptor validation now warns if change addresses cannot be determined
- Wallet customization prompt now warns about descriptor unloading when something is changed
- Fixed long wallet derivation path displaying issues
- Added PSBT Review Again button to sign menu for verifying details muiltiple times without reloading the PSBT
- Added confirmation prompt before exiting after showing signed PSBT QR code
- Sign message now supports binary file types
- Change Addresses menu hidden when descriptor cannot provide them
- List Addresses now allows swiping up or down to navigate to move between pages
- Hide Mnemonic now skips confirmation when loading via word numbers
- Text improvements for clarity and easier translation
- Fixed mixed ASCII/Asian fonts not using full display width
- Fixed menu entries cut off when translations span two lines
- Fixed entry update bug when switching between PAGE and swipe in large menus
- MaixPy Fix: Increased glyph indexing capacity for Amigo translations
- Fixed issue allowing incompatible script types from policies in Default Wallet settings
Krux community
Special thanks to:
@jdlcdl — for the huge amount of contributions, especially the excellent work on KEF.
@tadeubas — for numerous UI improvements, relentless bug hunting, and fixes.
@qlrd — for consistently creating and improving tests as well as contributing to the main codebase.
@crwatkins — for the thoughtful review of Krux code prior to its listing on bitcoin.org.
All active members of our Telegram group — for sharing great ideas, testing, and providing valuable feedback.
@OpenSats, HRF, and @CasaVinteUm — for supporting Krux contributors and the broader community.