a4fe14bb82
This commit adds support for the BitBox02 hardware wallet. It supports both single and multisig for the electrum gui wallet. To use the plugin a local installation of the BitBox02 python library is required. It can be found on PiPy under the name 'bitbox02' and can be installed from the bitbox02-firmware repository in the py/bitbox02 directory. All communication to and from the BitBox02 is noise encrypted, the keys required for this are stored in the wallet config file under the bitbox02 key. The BitBox02 registers a multisig configuration before allowing transaction signing. This multisig configuration includes the threshold, cosigner xpubs, keypath, a variable to indicate for mainnet and testnet, and a name that the user can choose during configuration registration. The user is asked to register the multisig configuration either during address verification or during transaction signing. The check the xpub of the BitBox02 for other hardware wallets, a button is added in the wallet info dialog. The wallet encryption key is fetched in a separate api call, requiring a slightly tweaked override version of the wallet encryption password. |
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| .. | ||
| __init__.py | ||
| cmdline.py | ||
| coldcard.py | ||
| qt.py | ||
| README.md | ||
Coldcard Hardware Wallet Plugin
Just the glue please
This code connects the public USB API and Electrum. Leverages all the good work that's been done by the Electrum team to support hardware wallets.
Background
The Coldcard has a larger screen (128x64) and a number pad. For this reason, all PIN code entry is done directly on the device. Coldcard does not appear on the USB bus until unlocked with appropriate PIN. Initial setup, and seed generation must be done offline.
Coldcard uses an emerging standard for unsigned tranasctions:
PSBT = Partially Signed Bitcoin Transaction = BIP174
However, this spec is still under heavy discussion and in flux. At this point, the PSBT files generated will only be compatible with Coldcard.
The Coldcard can be used 100% offline: it can generate a skeleton Electrum wallet and save it to MicroSD card. Transport that file to Electrum and it will fetch history, blockchain details and then operate in "unpaired" mode.
Spending transactions can be saved to MicroSD using the "Export PSBT" button on the transaction preview dialog (when this plugin is owner of the wallet). That PSBT can be signed on the Coldcard (again using MicroSD both ways). The result is a ready-to-transmit bitcoin transaction, which can be transmitted using Tools > Load Transaction > From File in Electrum or really any tool.
TODO Items
- No effort yet to support translations or languages other than English, sorry.
- Coldcard PSBT format is not likely to be compatible with other devices, because the BIP174 is still in flux.
- Segwit support not 100% complete: can pay to them, but cannot setup wallet to receive them.
- Limited support for segwit wrapped in P2SH.
- Someday we could support multisig hardware wallets based on PSBT where each participant is using different devices/systems for signing, however, that belongs in an independant plugin that is PSBT focused and might not require a Coldcard to be present.
Ctags
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I find this command useful (at top level) ... but I'm a VIM user.
ctags -f .tags electrum
find . -name ENV -prune -o -name \*.py
Working with latest ckcc-protocol
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at top level, do this:
pip install -e git+ssh://git@github.com/Coldcard/ckcc-protocol.git#egg=ckcc-protocol
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but you'll need the https version of that, not ssh like I can.
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also a branch name would be good in there
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do
pip uninstall ckccfirst