mirror of https://github.com/poanetwork/quorum.git
210 lines
7.0 KiB
Go
210 lines
7.0 KiB
Go
// Copyright 2017 The go-ethereum Authors
|
|
// This file is part of the go-ethereum library.
|
|
//
|
|
// The go-ethereum library is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Lesser General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// The go-ethereum library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public License
|
|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
// This file contains the implementation for interacting with the Ledger hardware
|
|
// wallets. The wire protocol spec can be found in the Ledger Blue GitHub repo:
|
|
// https://raw.githubusercontent.com/LedgerHQ/blue-app-eth/master/doc/ethapp.asc
|
|
|
|
// +build !ios
|
|
|
|
package usbwallet
|
|
|
|
import (
|
|
"fmt"
|
|
"sync"
|
|
"time"
|
|
|
|
"github.com/ethereum/go-ethereum/accounts"
|
|
"github.com/ethereum/go-ethereum/event"
|
|
"github.com/karalabe/gousb/usb"
|
|
)
|
|
|
|
// LedgerScheme is the protocol scheme prefixing account and wallet URLs.
|
|
var LedgerScheme = "ledger"
|
|
|
|
// ledgerDeviceIDs are the known device IDs that Ledger wallets use.
|
|
var ledgerDeviceIDs = []deviceID{
|
|
{Vendor: 0x2c97, Product: 0x0000}, // Ledger Blue
|
|
{Vendor: 0x2c97, Product: 0x0001}, // Ledger Nano S
|
|
}
|
|
|
|
// Maximum time between wallet refreshes (if USB hotplug notifications don't work).
|
|
const ledgerRefreshCycle = time.Second
|
|
|
|
// Minimum time between wallet refreshes to avoid USB trashing.
|
|
const ledgerRefreshThrottling = 500 * time.Millisecond
|
|
|
|
// LedgerHub is a accounts.Backend that can find and handle Ledger hardware wallets.
|
|
type LedgerHub struct {
|
|
ctx *usb.Context // Context interfacing with a libusb instance
|
|
|
|
refreshed time.Time // Time instance when the list of wallets was last refreshed
|
|
wallets []accounts.Wallet // List of Ledger devices currently tracking
|
|
updateFeed event.Feed // Event feed to notify wallet additions/removals
|
|
updateScope event.SubscriptionScope // Subscription scope tracking current live listeners
|
|
updating bool // Whether the event notification loop is running
|
|
|
|
quit chan chan error
|
|
lock sync.RWMutex
|
|
}
|
|
|
|
// NewLedgerHub creates a new hardware wallet manager for Ledger devices.
|
|
func NewLedgerHub() (*LedgerHub, error) {
|
|
// Initialize the USB library to access Ledgers through
|
|
ctx, err := usb.NewContext()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
// Create the USB hub, start and return it
|
|
hub := &LedgerHub{
|
|
ctx: ctx,
|
|
quit: make(chan chan error),
|
|
}
|
|
hub.refreshWallets()
|
|
|
|
return hub, nil
|
|
}
|
|
|
|
// Wallets implements accounts.Backend, returning all the currently tracked USB
|
|
// devices that appear to be Ledger hardware wallets.
|
|
func (hub *LedgerHub) Wallets() []accounts.Wallet {
|
|
// Make sure the list of wallets is up to date
|
|
hub.refreshWallets()
|
|
|
|
hub.lock.RLock()
|
|
defer hub.lock.RUnlock()
|
|
|
|
cpy := make([]accounts.Wallet, len(hub.wallets))
|
|
copy(cpy, hub.wallets)
|
|
return cpy
|
|
}
|
|
|
|
// refreshWallets scans the USB devices attached to the machine and updates the
|
|
// list of wallets based on the found devices.
|
|
func (hub *LedgerHub) refreshWallets() {
|
|
// Don't scan the USB like crazy it the user fetches wallets in a loop
|
|
hub.lock.RLock()
|
|
elapsed := time.Since(hub.refreshed)
|
|
hub.lock.RUnlock()
|
|
|
|
if elapsed < ledgerRefreshThrottling {
|
|
return
|
|
}
|
|
// Retrieve the current list of Ledger devices
|
|
var devIDs []deviceID
|
|
var busIDs []uint16
|
|
|
|
hub.ctx.ListDevices(func(desc *usb.Descriptor) bool {
|
|
// Gather Ledger devices, don't connect any just yet
|
|
for _, id := range ledgerDeviceIDs {
|
|
if desc.Vendor == id.Vendor && desc.Product == id.Product {
|
|
devIDs = append(devIDs, deviceID{Vendor: desc.Vendor, Product: desc.Product})
|
|
busIDs = append(busIDs, uint16(desc.Bus)<<8+uint16(desc.Address))
|
|
return false
|
|
}
|
|
}
|
|
// Not ledger, ignore and don't connect either
|
|
return false
|
|
})
|
|
// Transform the current list of wallets into the new one
|
|
hub.lock.Lock()
|
|
|
|
wallets := make([]accounts.Wallet, 0, len(devIDs))
|
|
events := []accounts.WalletEvent{}
|
|
|
|
for i := 0; i < len(devIDs); i++ {
|
|
devID, busID := devIDs[i], busIDs[i]
|
|
|
|
url := accounts.URL{Scheme: LedgerScheme, Path: fmt.Sprintf("%03d:%03d", busID>>8, busID&0xff)}
|
|
|
|
// Drop wallets in front of the next device or those that failed for some reason
|
|
for len(hub.wallets) > 0 && (hub.wallets[0].URL().Cmp(url) < 0 || hub.wallets[0].(*ledgerWallet).failed()) {
|
|
events = append(events, accounts.WalletEvent{Wallet: hub.wallets[0], Arrive: false})
|
|
hub.wallets = hub.wallets[1:]
|
|
}
|
|
// If there are no more wallets or the device is before the next, wrap new wallet
|
|
if len(hub.wallets) == 0 || hub.wallets[0].URL().Cmp(url) > 0 {
|
|
wallet := &ledgerWallet{context: hub.ctx, hardwareID: devID, locationID: busID, url: &url}
|
|
|
|
events = append(events, accounts.WalletEvent{Wallet: wallet, Arrive: true})
|
|
wallets = append(wallets, wallet)
|
|
continue
|
|
}
|
|
// If the device is the same as the first wallet, keep it
|
|
if hub.wallets[0].URL().Cmp(url) == 0 {
|
|
wallets = append(wallets, hub.wallets[0])
|
|
hub.wallets = hub.wallets[1:]
|
|
continue
|
|
}
|
|
}
|
|
// Drop any leftover wallets and set the new batch
|
|
for _, wallet := range hub.wallets {
|
|
events = append(events, accounts.WalletEvent{Wallet: wallet, Arrive: false})
|
|
}
|
|
hub.refreshed = time.Now()
|
|
hub.wallets = wallets
|
|
hub.lock.Unlock()
|
|
|
|
// Fire all wallet events and return
|
|
for _, event := range events {
|
|
hub.updateFeed.Send(event)
|
|
}
|
|
}
|
|
|
|
// Subscribe implements accounts.Backend, creating an async subscription to
|
|
// receive notifications on the addition or removal of Ledger wallets.
|
|
func (hub *LedgerHub) Subscribe(sink chan<- accounts.WalletEvent) event.Subscription {
|
|
// We need the mutex to reliably start/stop the update loop
|
|
hub.lock.Lock()
|
|
defer hub.lock.Unlock()
|
|
|
|
// Subscribe the caller and track the subscriber count
|
|
sub := hub.updateScope.Track(hub.updateFeed.Subscribe(sink))
|
|
|
|
// Subscribers require an active notification loop, start it
|
|
if !hub.updating {
|
|
hub.updating = true
|
|
go hub.updater()
|
|
}
|
|
return sub
|
|
}
|
|
|
|
// updater is responsible for maintaining an up-to-date list of wallets stored in
|
|
// the keystore, and for firing wallet addition/removal events. It listens for
|
|
// account change events from the underlying account cache, and also periodically
|
|
// forces a manual refresh (only triggers for systems where the filesystem notifier
|
|
// is not running).
|
|
func (hub *LedgerHub) updater() {
|
|
for {
|
|
// Wait for a USB hotplug event (not supported yet) or a refresh timeout
|
|
select {
|
|
//case <-hub.changes: // reenable on hutplug implementation
|
|
case <-time.After(ledgerRefreshCycle):
|
|
}
|
|
// Run the wallet refresher
|
|
hub.refreshWallets()
|
|
|
|
// If all our subscribers left, stop the updater
|
|
hub.lock.Lock()
|
|
if hub.updateScope.Count() == 0 {
|
|
hub.updating = false
|
|
hub.lock.Unlock()
|
|
return
|
|
}
|
|
hub.lock.Unlock()
|
|
}
|
|
}
|