accounts: refactor API for generalized USB wallets

This commit is contained in:
Péter Szilágyi 2017-08-09 12:51:16 +03:00
parent db568a61e2
commit 5d9ac49c7e
No known key found for this signature in database
GPG Key ID: E9AE538CEDF8293D
13 changed files with 1450 additions and 1965 deletions

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@ -42,8 +42,9 @@ type Wallet interface {
URL() URL URL() URL
// Status returns a textual status to aid the user in the current state of the // Status returns a textual status to aid the user in the current state of the
// wallet. // wallet. It also returns an error indicating any failure the wallet might have
Status() string // encountered.
Status() (string, error)
// Open initializes access to a wallet instance. It is not meant to unlock or // Open initializes access to a wallet instance. It is not meant to unlock or
// decrypt account keys, rather simply to establish a connection to hardware // decrypt account keys, rather simply to establish a connection to hardware

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@ -37,11 +37,11 @@ func TestHDPathParsing(t *testing.T) {
{"m/2147483692/2147483708/2147483648/2147483648", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}}, {"m/2147483692/2147483708/2147483648/2147483648", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}},
// Plain relative derivation paths // Plain relative derivation paths
{"0", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}}, {"0", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0}},
{"128", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 128}}, {"128", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 128}},
{"0'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}}, {"0'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 0}},
{"128'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 128}}, {"128'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 128}},
{"2147483648", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}}, {"2147483648", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 0}},
// Hexadecimal absolute derivation paths // Hexadecimal absolute derivation paths
{"m/0x2C'/0x3c'/0x00'/0x00", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}}, {"m/0x2C'/0x3c'/0x00'/0x00", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}},
@ -52,11 +52,11 @@ func TestHDPathParsing(t *testing.T) {
{"m/0x8000002C/0x8000003c/0x80000000/0x80000000", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}}, {"m/0x8000002C/0x8000003c/0x80000000/0x80000000", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}},
// Hexadecimal relative derivation paths // Hexadecimal relative derivation paths
{"0x00", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}}, {"0x00", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0}},
{"0x80", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 128}}, {"0x80", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 128}},
{"0x00'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}}, {"0x00'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 0}},
{"0x80'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 128}}, {"0x80'", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 128}},
{"0x80000000", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0x80000000 + 0}}, {"0x80000000", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0, 0x80000000 + 0}},
// Weird inputs just to ensure they work // Weird inputs just to ensure they work
{" m / 44 '\n/\n 60 \n\n\t' /\n0 ' /\t\t 0", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}}, {" m / 44 '\n/\n 60 \n\n\t' /\n0 ' /\t\t 0", DerivationPath{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0}},

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@ -36,16 +36,16 @@ func (w *keystoreWallet) URL() accounts.URL {
return w.account.URL return w.account.URL
} }
// Status implements accounts.Wallet, always returning "open", since there is no // Status implements accounts.Wallet, returning whether the account held by the
// concept of open/close for plain keystore accounts. // keystore wallet is unlocked or not.
func (w *keystoreWallet) Status() string { func (w *keystoreWallet) Status() (string, error) {
w.keystore.mu.RLock() w.keystore.mu.RLock()
defer w.keystore.mu.RUnlock() defer w.keystore.mu.RUnlock()
if _, ok := w.keystore.unlocked[w.account.Address]; ok { if _, ok := w.keystore.unlocked[w.account.Address]; ok {
return "Unlocked" return "Unlocked", nil
} }
return "Locked" return "Locked", nil
} }
// Open implements accounts.Wallet, but is a noop for plain wallets since there // Open implements accounts.Wallet, but is a noop for plain wallets since there

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@ -29,24 +29,28 @@ import (
) )
// LedgerScheme is the protocol scheme prefixing account and wallet URLs. // LedgerScheme is the protocol scheme prefixing account and wallet URLs.
var LedgerScheme = "ledger" const LedgerScheme = "ledger"
// ledgerDeviceIDs are the known device IDs that Ledger wallets use. // TrezorScheme is the protocol scheme prefixing account and wallet URLs.
var ledgerDeviceIDs = []deviceID{ const TrezorScheme = "trezor"
{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). // refreshCycle is the maximum time between wallet refreshes (if USB hotplug
const ledgerRefreshCycle = time.Second // notifications don't work).
const refreshCycle = time.Second
// Minimum time between wallet refreshes to avoid USB trashing. // refreshThrottling is the minimum time between wallet refreshes to avoid USB
const ledgerRefreshThrottling = 500 * time.Millisecond // trashing.
const refreshThrottling = 500 * time.Millisecond
// Hub is a accounts.Backend that can find and handle generic USB hardware wallets.
type Hub struct {
scheme string // Protocol scheme prefixing account and wallet URLs.
vendorID uint16 // USB vendor identifier used for device discovery
productIDs []uint16 // USB product identifiers used for device discovery
makeDriver func(log.Logger) driver // Factory method to construct a vendor specific driver
// LedgerHub is a accounts.Backend that can find and handle Ledger hardware wallets.
type LedgerHub struct {
refreshed time.Time // Time instance when the list of wallets was last refreshed refreshed time.Time // Time instance when the list of wallets was last refreshed
wallets []accounts.Wallet // List of Ledger devices currently tracking wallets []accounts.Wallet // List of USB wallet devices currently tracking
updateFeed event.Feed // Event feed to notify wallet additions/removals updateFeed event.Feed // Event feed to notify wallet additions/removals
updateScope event.SubscriptionScope // Subscription scope tracking current live listeners updateScope event.SubscriptionScope // Subscription scope tracking current live listeners
updating bool // Whether the event notification loop is running updating bool // Whether the event notification loop is running
@ -61,11 +65,25 @@ type LedgerHub struct {
} }
// NewLedgerHub creates a new hardware wallet manager for Ledger devices. // NewLedgerHub creates a new hardware wallet manager for Ledger devices.
func NewLedgerHub() (*LedgerHub, error) { func NewLedgerHub() (*Hub, error) {
return newHub(LedgerScheme, 0x2c97, []uint16{0x0000 /* Ledger Blue */, 0x0001 /* Ledger Nano S */}, newLedgerDriver)
}
// NewTrezorHub creates a new hardware wallet manager for Trezor devices.
func NewTrezorHub() (*Hub, error) {
return newHub(TrezorScheme, 0x534c, []uint16{0x0001 /* Trezor 1 */}, newTrezorDriver)
}
// newHub creates a new hardware wallet manager for generic USB devices.
func newHub(scheme string, vendorID uint16, productIDs []uint16, makeDriver func(log.Logger) driver) (*Hub, error) {
if !hid.Supported() { if !hid.Supported() {
return nil, errors.New("unsupported platform") return nil, errors.New("unsupported platform")
} }
hub := &LedgerHub{ hub := &Hub{
scheme: scheme,
vendorID: vendorID,
productIDs: productIDs,
makeDriver: makeDriver,
quit: make(chan chan error), quit: make(chan chan error),
} }
hub.refreshWallets() hub.refreshWallets()
@ -73,8 +91,8 @@ func NewLedgerHub() (*LedgerHub, error) {
} }
// Wallets implements accounts.Backend, returning all the currently tracked USB // Wallets implements accounts.Backend, returning all the currently tracked USB
// devices that appear to be Ledger hardware wallets. // devices that appear to be hardware wallets.
func (hub *LedgerHub) Wallets() []accounts.Wallet { func (hub *Hub) Wallets() []accounts.Wallet {
// Make sure the list of wallets is up to date // Make sure the list of wallets is up to date
hub.refreshWallets() hub.refreshWallets()
@ -88,17 +106,17 @@ func (hub *LedgerHub) Wallets() []accounts.Wallet {
// refreshWallets scans the USB devices attached to the machine and updates the // refreshWallets scans the USB devices attached to the machine and updates the
// list of wallets based on the found devices. // list of wallets based on the found devices.
func (hub *LedgerHub) refreshWallets() { func (hub *Hub) refreshWallets() {
// Don't scan the USB like crazy it the user fetches wallets in a loop // Don't scan the USB like crazy it the user fetches wallets in a loop
hub.stateLock.RLock() hub.stateLock.RLock()
elapsed := time.Since(hub.refreshed) elapsed := time.Since(hub.refreshed)
hub.stateLock.RUnlock() hub.stateLock.RUnlock()
if elapsed < ledgerRefreshThrottling { if elapsed < refreshThrottling {
return return
} }
// Retrieve the current list of Ledger devices // Retrieve the current list of USB wallet devices
var ledgers []hid.DeviceInfo var devices []hid.DeviceInfo
if runtime.GOOS == "linux" { if runtime.GOOS == "linux" {
// hidapi on Linux opens the device during enumeration to retrieve some infos, // hidapi on Linux opens the device during enumeration to retrieve some infos,
@ -113,10 +131,10 @@ func (hub *LedgerHub) refreshWallets() {
return return
} }
} }
for _, info := range hid.Enumerate(0, 0) { // Can't enumerate directly, one valid ID is the 0 wildcard for _, info := range hid.Enumerate(hub.vendorID, 0) {
for _, id := range ledgerDeviceIDs { for _, id := range hub.productIDs {
if info.VendorID == id.Vendor && info.ProductID == id.Product { if info.ProductID == id && info.Interface == 0 {
ledgers = append(ledgers, info) devices = append(devices, info)
break break
} }
} }
@ -128,20 +146,27 @@ func (hub *LedgerHub) refreshWallets() {
// Transform the current list of wallets into the new one // Transform the current list of wallets into the new one
hub.stateLock.Lock() hub.stateLock.Lock()
wallets := make([]accounts.Wallet, 0, len(ledgers)) wallets := make([]accounts.Wallet, 0, len(devices))
events := []accounts.WalletEvent{} events := []accounts.WalletEvent{}
for _, ledger := range ledgers { for _, device := range devices {
url := accounts.URL{Scheme: LedgerScheme, Path: ledger.Path} url := accounts.URL{Scheme: hub.scheme, Path: device.Path}
// Drop wallets in front of the next device or those that failed for some reason // 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()) { for len(hub.wallets) > 0 {
// Abort if we're past the current device and found an operational one
_, failure := hub.wallets[0].Status()
if hub.wallets[0].URL().Cmp(url) >= 0 || failure == nil {
break
}
// Drop the stale and failed devices
events = append(events, accounts.WalletEvent{Wallet: hub.wallets[0], Kind: accounts.WalletDropped}) events = append(events, accounts.WalletEvent{Wallet: hub.wallets[0], Kind: accounts.WalletDropped})
hub.wallets = hub.wallets[1:] hub.wallets = hub.wallets[1:]
} }
// If there are no more wallets or the device is before the next, wrap new wallet // 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 { if len(hub.wallets) == 0 || hub.wallets[0].URL().Cmp(url) > 0 {
wallet := &ledgerWallet{hub: hub, url: &url, info: ledger, log: log.New("url", url)} logger := log.New("url", url)
wallet := &wallet{hub: hub, driver: hub.makeDriver(logger), url: &url, info: device, log: logger}
events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletArrived}) events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletArrived})
wallets = append(wallets, wallet) wallets = append(wallets, wallet)
@ -169,8 +194,8 @@ func (hub *LedgerHub) refreshWallets() {
} }
// Subscribe implements accounts.Backend, creating an async subscription to // Subscribe implements accounts.Backend, creating an async subscription to
// receive notifications on the addition or removal of Ledger wallets. // receive notifications on the addition or removal of USB wallets.
func (hub *LedgerHub) Subscribe(sink chan<- accounts.WalletEvent) event.Subscription { func (hub *Hub) Subscribe(sink chan<- accounts.WalletEvent) event.Subscription {
// We need the mutex to reliably start/stop the update loop // We need the mutex to reliably start/stop the update loop
hub.stateLock.Lock() hub.stateLock.Lock()
defer hub.stateLock.Unlock() defer hub.stateLock.Unlock()
@ -186,16 +211,13 @@ func (hub *LedgerHub) Subscribe(sink chan<- accounts.WalletEvent) event.Subscrip
return sub return sub
} }
// updater is responsible for maintaining an up-to-date list of wallets stored in // updater is responsible for maintaining an up-to-date list of wallets managed
// the keystore, and for firing wallet addition/removal events. It listens for // by the USB hub, and for firing wallet addition/removal events.
// account change events from the underlying account cache, and also periodically func (hub *Hub) updater() {
// forces a manual refresh (only triggers for systems where the filesystem notifier
// is not running).
func (hub *LedgerHub) updater() {
for { for {
// TODO: Wait for a USB hotplug event (not supported yet) or a refresh timeout // TODO: Wait for a USB hotplug event (not supported yet) or a refresh timeout
// <-hub.changes // <-hub.changes
time.Sleep(ledgerRefreshCycle) time.Sleep(refreshCycle)
// Run the wallet refresher // Run the wallet refresher
hub.refreshWallets() hub.refreshWallets()

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@ -0,0 +1,464 @@
// 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
package usbwallet
import (
"encoding/binary"
"encoding/hex"
"errors"
"fmt"
"io"
"math/big"
"github.com/ethereum/go-ethereum/accounts"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/rlp"
)
// ledgerOpcode is an enumeration encoding the supported Ledger opcodes.
type ledgerOpcode byte
// ledgerParam1 is an enumeration encoding the supported Ledger parameters for
// specific opcodes. The same parameter values may be reused between opcodes.
type ledgerParam1 byte
// ledgerParam2 is an enumeration encoding the supported Ledger parameters for
// specific opcodes. The same parameter values may be reused between opcodes.
type ledgerParam2 byte
const (
ledgerOpRetrieveAddress ledgerOpcode = 0x02 // Returns the public key and Ethereum address for a given BIP 32 path
ledgerOpSignTransaction ledgerOpcode = 0x04 // Signs an Ethereum transaction after having the user validate the parameters
ledgerOpGetConfiguration ledgerOpcode = 0x06 // Returns specific wallet application configuration
ledgerP1DirectlyFetchAddress ledgerParam1 = 0x00 // Return address directly from the wallet
ledgerP1ConfirmFetchAddress ledgerParam1 = 0x01 // Require a user confirmation before returning the address
ledgerP1InitTransactionData ledgerParam1 = 0x00 // First transaction data block for signing
ledgerP1ContTransactionData ledgerParam1 = 0x80 // Subsequent transaction data block for signing
ledgerP2DiscardAddressChainCode ledgerParam2 = 0x00 // Do not return the chain code along with the address
ledgerP2ReturnAddressChainCode ledgerParam2 = 0x01 // Require a user confirmation before returning the address
)
// errLedgerReplyInvalidHeader is the error message returned by a Ledger data exchange
// if the device replies with a mismatching header. This usually means the device
// is in browser mode.
var errLedgerReplyInvalidHeader = errors.New("ledger: invalid reply header")
// errLedgerInvalidVersionReply is the error message returned by a Ledger version retrieval
// when a response does arrive, but it does not contain the expected data.
var errLedgerInvalidVersionReply = errors.New("ledger: invalid version reply")
// ledgerDriver implements the communication with a Ledger hardware wallet.
type ledgerDriver struct {
device io.ReadWriter // USB device connection to communicate through
version [3]byte // Current version of the Ledger firmware (zero if app is offline)
browser bool // Flag whether the Ledger is in browser mode (reply channel mismatch)
failure error // Any failure that would make the device unusable
log log.Logger // Contextual logger to tag the ledger with its id
}
// newLedgerDriver creates a new instance of a Ledger USB protocol driver.
func newLedgerDriver(logger log.Logger) driver {
return &ledgerDriver{
log: logger,
}
}
// Status implements usbwallet.driver, returning various states the Ledger can
// currently be in.
func (w *ledgerDriver) Status() (string, error) {
if w.failure != nil {
return fmt.Sprintf("Failed: %v", w.failure), w.failure
}
if w.browser {
return "Ethereum app in browser mode", w.failure
}
if w.offline() {
return "Ethereum app offline", w.failure
}
return fmt.Sprintf("Ethereum app v%d.%d.%d online", w.version[0], w.version[1], w.version[2]), w.failure
}
// offline returns whether the wallet and the Ethereum app is offline or not.
//
// The method assumes that the state lock is held!
func (w *ledgerDriver) offline() bool {
return w.version == [3]byte{0, 0, 0}
}
// Open implements usbwallet.driver, attempting to initialize the connection to the
// Ledger hardware wallet. The Ledger does not require a user passphrase, so that
// parameter is silently discarded.
func (w *ledgerDriver) Open(device io.ReadWriter, passphrase string) error {
w.device, w.failure = device, nil
_, err := w.ledgerDerive(accounts.DefaultBaseDerivationPath)
if err != nil {
// Ethereum app is not running or in browser mode, nothing more to do, return
if err == errLedgerReplyInvalidHeader {
w.browser = true
}
return nil
}
// Try to resolve the Ethereum app's version, will fail prior to v1.0.2
if w.version, err = w.ledgerVersion(); err != nil {
w.version = [3]byte{1, 0, 0} // Assume worst case, can't verify if v1.0.0 or v1.0.1
}
return nil
}
// Close implements usbwallet.driver, cleaning up and metadata maintained within
// the Ledger driver.
func (w *ledgerDriver) Close() error {
w.browser, w.version = false, [3]byte{}
return nil
}
// Heartbeat implements usbwallet.driver, performing a sanity check against the
// Ledger to see if it's still online.
func (w *ledgerDriver) Heartbeat() error {
if _, err := w.ledgerVersion(); err != nil && err != errLedgerInvalidVersionReply {
w.failure = err
return err
}
return nil
}
// Derive implements usbwallet.driver, sending a derivation request to the Ledger
// and returning the Ethereum address located on that derivation path.
func (w *ledgerDriver) Derive(path accounts.DerivationPath) (common.Address, error) {
return w.ledgerDerive(path)
}
// SignTx implements usbwallet.driver, sending the transaction to the Ledger and
// waiting for the user to confirm or deny the transaction.
//
// Note, if the version of the Ethereum application running on the Ledger wallet is
// too old to sign EIP-155 transactions, but such is requested nonetheless, an error
// will be returned opposed to silently signing in Homestead mode.
func (w *ledgerDriver) SignTx(path accounts.DerivationPath, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
// If the Ethereum app doesn't run, abort
if w.offline() {
return common.Address{}, nil, accounts.ErrWalletClosed
}
// Ensure the wallet is capable of signing the given transaction
if chainID != nil && w.version[0] <= 1 && w.version[1] <= 0 && w.version[2] <= 2 {
return common.Address{}, nil, fmt.Errorf("Ledger v%d.%d.%d doesn't support signing this transaction, please update to v1.0.3 at least", w.version[0], w.version[1], w.version[2])
}
// All infos gathered and metadata checks out, request signing
return w.ledgerSign(path, tx, chainID)
}
// ledgerVersion retrieves the current version of the Ethereum wallet app running
// on the Ledger wallet.
//
// The version retrieval protocol is defined as follows:
//
// CLA | INS | P1 | P2 | Lc | Le
// ----+-----+----+----+----+---
// E0 | 06 | 00 | 00 | 00 | 04
//
// With no input data, and the output data being:
//
// Description | Length
// ---------------------------------------------------+--------
// Flags 01: arbitrary data signature enabled by user | 1 byte
// Application major version | 1 byte
// Application minor version | 1 byte
// Application patch version | 1 byte
func (w *ledgerDriver) ledgerVersion() ([3]byte, error) {
// Send the request and wait for the response
reply, err := w.ledgerExchange(ledgerOpGetConfiguration, 0, 0, nil)
if err != nil {
return [3]byte{}, err
}
if len(reply) != 4 {
return [3]byte{}, errLedgerInvalidVersionReply
}
// Cache the version for future reference
var version [3]byte
copy(version[:], reply[1:])
return version, nil
}
// ledgerDerive retrieves the currently active Ethereum address from a Ledger
// wallet at the specified derivation path.
//
// The address derivation protocol is defined as follows:
//
// CLA | INS | P1 | P2 | Lc | Le
// ----+-----+----+----+-----+---
// E0 | 02 | 00 return address
// 01 display address and confirm before returning
// | 00: do not return the chain code
// | 01: return the chain code
// | var | 00
//
// Where the input data is:
//
// Description | Length
// -------------------------------------------------+--------
// Number of BIP 32 derivations to perform (max 10) | 1 byte
// First derivation index (big endian) | 4 bytes
// ... | 4 bytes
// Last derivation index (big endian) | 4 bytes
//
// And the output data is:
//
// Description | Length
// ------------------------+-------------------
// Public Key length | 1 byte
// Uncompressed Public Key | arbitrary
// Ethereum address length | 1 byte
// Ethereum address | 40 bytes hex ascii
// Chain code if requested | 32 bytes
func (w *ledgerDriver) ledgerDerive(derivationPath []uint32) (common.Address, error) {
// Flatten the derivation path into the Ledger request
path := make([]byte, 1+4*len(derivationPath))
path[0] = byte(len(derivationPath))
for i, component := range derivationPath {
binary.BigEndian.PutUint32(path[1+4*i:], component)
}
// Send the request and wait for the response
reply, err := w.ledgerExchange(ledgerOpRetrieveAddress, ledgerP1DirectlyFetchAddress, ledgerP2DiscardAddressChainCode, path)
if err != nil {
return common.Address{}, err
}
// Discard the public key, we don't need that for now
if len(reply) < 1 || len(reply) < 1+int(reply[0]) {
return common.Address{}, errors.New("reply lacks public key entry")
}
reply = reply[1+int(reply[0]):]
// Extract the Ethereum hex address string
if len(reply) < 1 || len(reply) < 1+int(reply[0]) {
return common.Address{}, errors.New("reply lacks address entry")
}
hexstr := reply[1 : 1+int(reply[0])]
// Decode the hex sting into an Ethereum address and return
var address common.Address
hex.Decode(address[:], hexstr)
return address, nil
}
// ledgerSign sends the transaction to the Ledger wallet, and waits for the user
// to confirm or deny the transaction.
//
// The transaction signing protocol is defined as follows:
//
// CLA | INS | P1 | P2 | Lc | Le
// ----+-----+----+----+-----+---
// E0 | 04 | 00: first transaction data block
// 80: subsequent transaction data block
// | 00 | variable | variable
//
// Where the input for the first transaction block (first 255 bytes) is:
//
// Description | Length
// -------------------------------------------------+----------
// Number of BIP 32 derivations to perform (max 10) | 1 byte
// First derivation index (big endian) | 4 bytes
// ... | 4 bytes
// Last derivation index (big endian) | 4 bytes
// RLP transaction chunk | arbitrary
//
// And the input for subsequent transaction blocks (first 255 bytes) are:
//
// Description | Length
// ----------------------+----------
// RLP transaction chunk | arbitrary
//
// And the output data is:
//
// Description | Length
// ------------+---------
// signature V | 1 byte
// signature R | 32 bytes
// signature S | 32 bytes
func (w *ledgerDriver) ledgerSign(derivationPath []uint32, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
// Flatten the derivation path into the Ledger request
path := make([]byte, 1+4*len(derivationPath))
path[0] = byte(len(derivationPath))
for i, component := range derivationPath {
binary.BigEndian.PutUint32(path[1+4*i:], component)
}
// Create the transaction RLP based on whether legacy or EIP155 signing was requeste
var (
txrlp []byte
err error
)
if chainID == nil {
if txrlp, err = rlp.EncodeToBytes([]interface{}{tx.Nonce(), tx.GasPrice(), tx.Gas(), tx.To(), tx.Value(), tx.Data()}); err != nil {
return common.Address{}, nil, err
}
} else {
if txrlp, err = rlp.EncodeToBytes([]interface{}{tx.Nonce(), tx.GasPrice(), tx.Gas(), tx.To(), tx.Value(), tx.Data(), chainID, big.NewInt(0), big.NewInt(0)}); err != nil {
return common.Address{}, nil, err
}
}
payload := append(path, txrlp...)
// Send the request and wait for the response
var (
op = ledgerP1InitTransactionData
reply []byte
)
for len(payload) > 0 {
// Calculate the size of the next data chunk
chunk := 255
if chunk > len(payload) {
chunk = len(payload)
}
// Send the chunk over, ensuring it's processed correctly
reply, err = w.ledgerExchange(ledgerOpSignTransaction, op, 0, payload[:chunk])
if err != nil {
return common.Address{}, nil, err
}
// Shift the payload and ensure subsequent chunks are marked as such
payload = payload[chunk:]
op = ledgerP1ContTransactionData
}
// Extract the Ethereum signature and do a sanity validation
if len(reply) != 65 {
return common.Address{}, nil, errors.New("reply lacks signature")
}
signature := append(reply[1:], reply[0])
// Create the correct signer and signature transform based on the chain ID
var signer types.Signer
if chainID == nil {
signer = new(types.HomesteadSigner)
} else {
signer = types.NewEIP155Signer(chainID)
signature[64] = signature[64] - byte(chainID.Uint64()*2+35)
}
signed, err := tx.WithSignature(signer, signature)
if err != nil {
return common.Address{}, nil, err
}
sender, err := types.Sender(signer, signed)
if err != nil {
return common.Address{}, nil, err
}
return sender, signed, nil
}
// ledgerExchange performs a data exchange with the Ledger wallet, sending it a
// message and retrieving the response.
//
// The common transport header is defined as follows:
//
// Description | Length
// --------------------------------------+----------
// Communication channel ID (big endian) | 2 bytes
// Command tag | 1 byte
// Packet sequence index (big endian) | 2 bytes
// Payload | arbitrary
//
// The Communication channel ID allows commands multiplexing over the same
// physical link. It is not used for the time being, and should be set to 0101
// to avoid compatibility issues with implementations ignoring a leading 00 byte.
//
// The Command tag describes the message content. Use TAG_APDU (0x05) for standard
// APDU payloads, or TAG_PING (0x02) for a simple link test.
//
// The Packet sequence index describes the current sequence for fragmented payloads.
// The first fragment index is 0x00.
//
// APDU Command payloads are encoded as follows:
//
// Description | Length
// -----------------------------------
// APDU length (big endian) | 2 bytes
// APDU CLA | 1 byte
// APDU INS | 1 byte
// APDU P1 | 1 byte
// APDU P2 | 1 byte
// APDU length | 1 byte
// Optional APDU data | arbitrary
func (w *ledgerDriver) ledgerExchange(opcode ledgerOpcode, p1 ledgerParam1, p2 ledgerParam2, data []byte) ([]byte, error) {
// Construct the message payload, possibly split into multiple chunks
apdu := make([]byte, 2, 7+len(data))
binary.BigEndian.PutUint16(apdu, uint16(5+len(data)))
apdu = append(apdu, []byte{0xe0, byte(opcode), byte(p1), byte(p2), byte(len(data))}...)
apdu = append(apdu, data...)
// Stream all the chunks to the device
header := []byte{0x01, 0x01, 0x05, 0x00, 0x00} // Channel ID and command tag appended
chunk := make([]byte, 64)
space := len(chunk) - len(header)
for i := 0; len(apdu) > 0; i++ {
// Construct the new message to stream
chunk = append(chunk[:0], header...)
binary.BigEndian.PutUint16(chunk[3:], uint16(i))
if len(apdu) > space {
chunk = append(chunk, apdu[:space]...)
apdu = apdu[space:]
} else {
chunk = append(chunk, apdu...)
apdu = nil
}
// Send over to the device
w.log.Trace("Data chunk sent to the Ledger", "chunk", hexutil.Bytes(chunk))
if _, err := w.device.Write(chunk); err != nil {
return nil, err
}
}
// Stream the reply back from the wallet in 64 byte chunks
var reply []byte
chunk = chunk[:64] // Yeah, we surely have enough space
for {
// Read the next chunk from the Ledger wallet
if _, err := io.ReadFull(w.device, chunk); err != nil {
return nil, err
}
w.log.Trace("Data chunk received from the Ledger", "chunk", hexutil.Bytes(chunk))
// Make sure the transport header matches
if chunk[0] != 0x01 || chunk[1] != 0x01 || chunk[2] != 0x05 {
return nil, errLedgerReplyInvalidHeader
}
// If it's the first chunk, retrieve the total message length
var payload []byte
if chunk[3] == 0x00 && chunk[4] == 0x00 {
reply = make([]byte, 0, int(binary.BigEndian.Uint16(chunk[5:7])))
payload = chunk[7:]
} else {
payload = chunk[5:]
}
// Append to the reply and stop when filled up
if left := cap(reply) - len(reply); left > len(payload) {
reply = append(reply, payload...)
} else {
reply = append(reply, payload[:left]...)
break
}
}
return reply[:len(reply)-2], nil
}

View File

@ -1,898 +0,0 @@
// 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
package usbwallet
import (
"context"
"encoding/binary"
"encoding/hex"
"errors"
"fmt"
"io"
"math/big"
"sync"
"time"
ethereum "github.com/ethereum/go-ethereum"
"github.com/ethereum/go-ethereum/accounts"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/rlp"
"github.com/karalabe/hid"
)
// ledgerOpcode is an enumeration encoding the supported Ledger opcodes.
type ledgerOpcode byte
// ledgerParam1 is an enumeration encoding the supported Ledger parameters for
// specific opcodes. The same parameter values may be reused between opcodes.
type ledgerParam1 byte
// ledgerParam2 is an enumeration encoding the supported Ledger parameters for
// specific opcodes. The same parameter values may be reused between opcodes.
type ledgerParam2 byte
const (
ledgerOpRetrieveAddress ledgerOpcode = 0x02 // Returns the public key and Ethereum address for a given BIP 32 path
ledgerOpSignTransaction ledgerOpcode = 0x04 // Signs an Ethereum transaction after having the user validate the parameters
ledgerOpGetConfiguration ledgerOpcode = 0x06 // Returns specific wallet application configuration
ledgerP1DirectlyFetchAddress ledgerParam1 = 0x00 // Return address directly from the wallet
ledgerP1ConfirmFetchAddress ledgerParam1 = 0x01 // Require a user confirmation before returning the address
ledgerP1InitTransactionData ledgerParam1 = 0x00 // First transaction data block for signing
ledgerP1ContTransactionData ledgerParam1 = 0x80 // Subsequent transaction data block for signing
ledgerP2DiscardAddressChainCode ledgerParam2 = 0x00 // Do not return the chain code along with the address
ledgerP2ReturnAddressChainCode ledgerParam2 = 0x01 // Require a user confirmation before returning the address
)
// errReplyInvalidHeader is the error message returned by a Ledger data exchange
// if the device replies with a mismatching header. This usually means the device
// is in browser mode.
var errReplyInvalidHeader = errors.New("invalid reply header")
// errInvalidVersionReply is the error message returned by a Ledger version retrieval
// when a response does arrive, but it does not contain the expected data.
var errInvalidVersionReply = errors.New("invalid version reply")
// ledgerWallet represents a live USB Ledger hardware wallet.
type ledgerWallet struct {
hub *LedgerHub // USB hub the device originates from (TODO(karalabe): remove if hotplug lands on Windows)
url *accounts.URL // Textual URL uniquely identifying this wallet
info hid.DeviceInfo // Known USB device infos about the wallet
device *hid.Device // USB device advertising itself as a Ledger wallet
failure error // Any failure that would make the device unusable
version [3]byte // Current version of the Ledger Ethereum app (zero if app is offline)
browser bool // Flag whether the Ledger is in browser mode (reply channel mismatch)
accounts []accounts.Account // List of derive accounts pinned on the Ledger
paths map[common.Address]accounts.DerivationPath // Known derivation paths for signing operations
deriveNextPath accounts.DerivationPath // Next derivation path for account auto-discovery
deriveNextAddr common.Address // Next derived account address for auto-discovery
deriveChain ethereum.ChainStateReader // Blockchain state reader to discover used account with
deriveReq chan chan struct{} // Channel to request a self-derivation on
deriveQuit chan chan error // Channel to terminate the self-deriver with
healthQuit chan chan error
// Locking a hardware wallet is a bit special. Since hardware devices are lower
// performing, any communication with them might take a non negligible amount of
// time. Worse still, waiting for user confirmation can take arbitrarily long,
// but exclusive communication must be upheld during. Locking the entire wallet
// in the mean time however would stall any parts of the system that don't want
// to communicate, just read some state (e.g. list the accounts).
//
// As such, a hardware wallet needs two locks to function correctly. A state
// lock can be used to protect the wallet's software-side internal state, which
// must not be held exlusively during hardware communication. A communication
// lock can be used to achieve exclusive access to the device itself, this one
// however should allow "skipping" waiting for operations that might want to
// use the device, but can live without too (e.g. account self-derivation).
//
// Since we have two locks, it's important to know how to properly use them:
// - Communication requires the `device` to not change, so obtaining the
// commsLock should be done after having a stateLock.
// - Communication must not disable read access to the wallet state, so it
// must only ever hold a *read* lock to stateLock.
commsLock chan struct{} // Mutex (buf=1) for the USB comms without keeping the state locked
stateLock sync.RWMutex // Protects read and write access to the wallet struct fields
log log.Logger // Contextual logger to tag the ledger with its id
}
// URL implements accounts.Wallet, returning the URL of the Ledger device.
func (w *ledgerWallet) URL() accounts.URL {
return *w.url // Immutable, no need for a lock
}
// Status implements accounts.Wallet, always whether the Ledger is opened, closed
// or whether the Ethereum app was not started on it.
func (w *ledgerWallet) Status() string {
w.stateLock.RLock() // No device communication, state lock is enough
defer w.stateLock.RUnlock()
if w.failure != nil {
return fmt.Sprintf("Failed: %v", w.failure)
}
if w.device == nil {
return "Closed"
}
if w.browser {
return "Ethereum app in browser mode"
}
if w.offline() {
return "Ethereum app offline"
}
return fmt.Sprintf("Ethereum app v%d.%d.%d online", w.version[0], w.version[1], w.version[2])
}
// offline returns whether the wallet and the Ethereum app is offline or not.
//
// The method assumes that the state lock is held!
func (w *ledgerWallet) offline() bool {
return w.version == [3]byte{0, 0, 0}
}
// failed returns if the USB device wrapped by the wallet failed for some reason.
// This is used by the device scanner to report failed wallets as departed.
//
// The method assumes that the state lock is *not* held!
func (w *ledgerWallet) failed() bool {
w.stateLock.RLock() // No device communication, state lock is enough
defer w.stateLock.RUnlock()
return w.failure != nil
}
// Open implements accounts.Wallet, attempting to open a USB connection to the
// Ledger hardware wallet. The Ledger does not require a user passphrase, so that
// parameter is silently discarded.
func (w *ledgerWallet) Open(passphrase string) error {
w.stateLock.Lock() // State lock is enough since there's no connection yet at this point
defer w.stateLock.Unlock()
// If the wallet was already opened, don't try to open again
if w.device != nil {
return accounts.ErrWalletAlreadyOpen
}
// Otherwise iterate over all USB devices and find this again (no way to directly do this)
device, err := w.info.Open()
if err != nil {
return err
}
// Wallet seems to be successfully opened, guess if the Ethereum app is running
w.device = device
w.commsLock = make(chan struct{}, 1)
w.commsLock <- struct{}{} // Enable lock
w.paths = make(map[common.Address]accounts.DerivationPath)
w.deriveReq = make(chan chan struct{})
w.deriveQuit = make(chan chan error)
w.healthQuit = make(chan chan error)
defer func() {
go w.heartbeat()
go w.selfDerive()
}()
if _, err = w.ledgerDerive(accounts.DefaultBaseDerivationPath); err != nil {
// Ethereum app is not running or in browser mode, nothing more to do, return
if err == errReplyInvalidHeader {
w.browser = true
}
return nil
}
// Try to resolve the Ethereum app's version, will fail prior to v1.0.2
if w.version, err = w.ledgerVersion(); err != nil {
w.version = [3]byte{1, 0, 0} // Assume worst case, can't verify if v1.0.0 or v1.0.1
}
go w.hub.updateFeed.Send(accounts.WalletEvent{Wallet: w, Kind: accounts.WalletOpened})
return nil
}
// heartbeat is a health check loop for the Ledger wallets to periodically verify
// whether they are still present or if they malfunctioned. It is needed because:
// - libusb on Windows doesn't support hotplug, so we can't detect USB unplugs
// - communication timeout on the Ledger requires a device power cycle to fix
func (w *ledgerWallet) heartbeat() {
w.log.Debug("Ledger health-check started")
defer w.log.Debug("Ledger health-check stopped")
// Execute heartbeat checks until termination or error
var (
errc chan error
err error
)
for errc == nil && err == nil {
// Wait until termination is requested or the heartbeat cycle arrives
select {
case errc = <-w.healthQuit:
// Termination requested
continue
case <-time.After(heartbeatCycle):
// Heartbeat time
}
// Execute a tiny data exchange to see responsiveness
w.stateLock.RLock()
if w.device == nil {
// Terminated while waiting for the lock
w.stateLock.RUnlock()
continue
}
<-w.commsLock // Don't lock state while resolving version
_, err = w.ledgerVersion()
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
if err != nil && err != errInvalidVersionReply {
w.stateLock.Lock() // Lock state to tear the wallet down
w.failure = err
w.close()
w.stateLock.Unlock()
}
// Ignore non hardware related errors
err = nil
}
// In case of error, wait for termination
if err != nil {
w.log.Debug("Ledger health-check failed", "err", err)
errc = <-w.healthQuit
}
errc <- err
}
// Close implements accounts.Wallet, closing the USB connection to the Ledger.
func (w *ledgerWallet) Close() error {
// Ensure the wallet was opened
w.stateLock.RLock()
hQuit, dQuit := w.healthQuit, w.deriveQuit
w.stateLock.RUnlock()
// Terminate the health checks
var herr error
if hQuit != nil {
errc := make(chan error)
hQuit <- errc
herr = <-errc // Save for later, we *must* close the USB
}
// Terminate the self-derivations
var derr error
if dQuit != nil {
errc := make(chan error)
dQuit <- errc
derr = <-errc // Save for later, we *must* close the USB
}
// Terminate the device connection
w.stateLock.Lock()
defer w.stateLock.Unlock()
w.healthQuit = nil
w.deriveQuit = nil
w.deriveReq = nil
if err := w.close(); err != nil {
return err
}
if herr != nil {
return herr
}
return derr
}
// close is the internal wallet closer that terminates the USB connection and
// resets all the fields to their defaults.
//
// Note, close assumes the state lock is held!
func (w *ledgerWallet) close() error {
// Allow duplicate closes, especially for health-check failures
if w.device == nil {
return nil
}
// Close the device, clear everything, then return
w.device.Close()
w.device = nil
w.browser, w.version = false, [3]byte{}
w.accounts, w.paths = nil, nil
return nil
}
// Accounts implements accounts.Wallet, returning the list of accounts pinned to
// the Ledger hardware wallet. If self-derivation was enabled, the account list
// is periodically expanded based on current chain state.
func (w *ledgerWallet) Accounts() []accounts.Account {
// Attempt self-derivation if it's running
reqc := make(chan struct{}, 1)
select {
case w.deriveReq <- reqc:
// Self-derivation request accepted, wait for it
<-reqc
default:
// Self-derivation offline, throttled or busy, skip
}
// Return whatever account list we ended up with
w.stateLock.RLock()
defer w.stateLock.RUnlock()
cpy := make([]accounts.Account, len(w.accounts))
copy(cpy, w.accounts)
return cpy
}
// selfDerive is an account derivation loop that upon request attempts to find
// new non-zero accounts.
func (w *ledgerWallet) selfDerive() {
w.log.Debug("Ledger self-derivation started")
defer w.log.Debug("Ledger self-derivation stopped")
// Execute self-derivations until termination or error
var (
reqc chan struct{}
errc chan error
err error
)
for errc == nil && err == nil {
// Wait until either derivation or termination is requested
select {
case errc = <-w.deriveQuit:
// Termination requested
continue
case reqc = <-w.deriveReq:
// Account discovery requested
}
// Derivation needs a chain and device access, skip if either unavailable
w.stateLock.RLock()
if w.device == nil || w.deriveChain == nil || w.offline() {
w.stateLock.RUnlock()
reqc <- struct{}{}
continue
}
select {
case <-w.commsLock:
default:
w.stateLock.RUnlock()
reqc <- struct{}{}
continue
}
// Device lock obtained, derive the next batch of accounts
var (
accs []accounts.Account
paths []accounts.DerivationPath
nextAddr = w.deriveNextAddr
nextPath = w.deriveNextPath
context = context.Background()
)
for empty := false; !empty; {
// Retrieve the next derived Ethereum account
if nextAddr == (common.Address{}) {
if nextAddr, err = w.ledgerDerive(nextPath); err != nil {
w.log.Warn("Ledger account derivation failed", "err", err)
break
}
}
// Check the account's status against the current chain state
var (
balance *big.Int
nonce uint64
)
balance, err = w.deriveChain.BalanceAt(context, nextAddr, nil)
if err != nil {
w.log.Warn("Ledger balance retrieval failed", "err", err)
break
}
nonce, err = w.deriveChain.NonceAt(context, nextAddr, nil)
if err != nil {
w.log.Warn("Ledger nonce retrieval failed", "err", err)
break
}
// If the next account is empty, stop self-derivation, but add it nonetheless
if balance.Sign() == 0 && nonce == 0 {
empty = true
}
// We've just self-derived a new account, start tracking it locally
path := make(accounts.DerivationPath, len(nextPath))
copy(path[:], nextPath[:])
paths = append(paths, path)
account := accounts.Account{
Address: nextAddr,
URL: accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)},
}
accs = append(accs, account)
// Display a log message to the user for new (or previously empty accounts)
if _, known := w.paths[nextAddr]; !known || (!empty && nextAddr == w.deriveNextAddr) {
w.log.Info("Ledger discovered new account", "address", nextAddr, "path", path, "balance", balance, "nonce", nonce)
}
// Fetch the next potential account
if !empty {
nextAddr = common.Address{}
nextPath[len(nextPath)-1]++
}
}
// Self derivation complete, release device lock
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
// Insert any accounts successfully derived
w.stateLock.Lock()
for i := 0; i < len(accs); i++ {
if _, ok := w.paths[accs[i].Address]; !ok {
w.accounts = append(w.accounts, accs[i])
w.paths[accs[i].Address] = paths[i]
}
}
// Shift the self-derivation forward
// TODO(karalabe): don't overwrite changes from wallet.SelfDerive
w.deriveNextAddr = nextAddr
w.deriveNextPath = nextPath
w.stateLock.Unlock()
// Notify the user of termination and loop after a bit of time (to avoid trashing)
reqc <- struct{}{}
if err == nil {
select {
case errc = <-w.deriveQuit:
// Termination requested, abort
case <-time.After(selfDeriveThrottling):
// Waited enough, willing to self-derive again
}
}
}
// In case of error, wait for termination
if err != nil {
w.log.Debug("Ledger self-derivation failed", "err", err)
errc = <-w.deriveQuit
}
errc <- err
}
// Contains implements accounts.Wallet, returning whether a particular account is
// or is not pinned into this Ledger instance. Although we could attempt to resolve
// unpinned accounts, that would be an non-negligible hardware operation.
func (w *ledgerWallet) Contains(account accounts.Account) bool {
w.stateLock.RLock()
defer w.stateLock.RUnlock()
_, exists := w.paths[account.Address]
return exists
}
// Derive implements accounts.Wallet, deriving a new account at the specific
// derivation path. If pin is set to true, the account will be added to the list
// of tracked accounts.
func (w *ledgerWallet) Derive(path accounts.DerivationPath, pin bool) (accounts.Account, error) {
// Try to derive the actual account and update its URL if successful
w.stateLock.RLock() // Avoid device disappearing during derivation
if w.device == nil || w.offline() {
w.stateLock.RUnlock()
return accounts.Account{}, accounts.ErrWalletClosed
}
<-w.commsLock // Avoid concurrent hardware access
address, err := w.ledgerDerive(path)
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
// If an error occurred or no pinning was requested, return
if err != nil {
return accounts.Account{}, err
}
account := accounts.Account{
Address: address,
URL: accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)},
}
if !pin {
return account, nil
}
// Pinning needs to modify the state
w.stateLock.Lock()
defer w.stateLock.Unlock()
if _, ok := w.paths[address]; !ok {
w.accounts = append(w.accounts, account)
w.paths[address] = path
}
return account, nil
}
// SelfDerive implements accounts.Wallet, trying to discover accounts that the
// user used previously (based on the chain state), but ones that he/she did not
// explicitly pin to the wallet manually. To avoid chain head monitoring, self
// derivation only runs during account listing (and even then throttled).
func (w *ledgerWallet) SelfDerive(base accounts.DerivationPath, chain ethereum.ChainStateReader) {
w.stateLock.Lock()
defer w.stateLock.Unlock()
w.deriveNextPath = make(accounts.DerivationPath, len(base))
copy(w.deriveNextPath[:], base[:])
w.deriveNextAddr = common.Address{}
w.deriveChain = chain
}
// SignHash implements accounts.Wallet, however signing arbitrary data is not
// supported for Ledger wallets, so this method will always return an error.
func (w *ledgerWallet) SignHash(acc accounts.Account, hash []byte) ([]byte, error) {
return nil, accounts.ErrNotSupported
}
// SignTx implements accounts.Wallet. It sends the transaction over to the Ledger
// wallet to request a confirmation from the user. It returns either the signed
// transaction or a failure if the user denied the transaction.
//
// Note, if the version of the Ethereum application running on the Ledger wallet is
// too old to sign EIP-155 transactions, but such is requested nonetheless, an error
// will be returned opposed to silently signing in Homestead mode.
func (w *ledgerWallet) SignTx(account accounts.Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
w.stateLock.RLock() // Comms have own mutex, this is for the state fields
defer w.stateLock.RUnlock()
// If the wallet is closed, or the Ethereum app doesn't run, abort
if w.device == nil || w.offline() {
return nil, accounts.ErrWalletClosed
}
// Make sure the requested account is contained within
path, ok := w.paths[account.Address]
if !ok {
return nil, accounts.ErrUnknownAccount
}
// Ensure the wallet is capable of signing the given transaction
if chainID != nil && w.version[0] <= 1 && w.version[1] <= 0 && w.version[2] <= 2 {
return nil, fmt.Errorf("Ledger v%d.%d.%d doesn't support signing this transaction, please update to v1.0.3 at least", w.version[0], w.version[1], w.version[2])
}
// All infos gathered and metadata checks out, request signing
<-w.commsLock
defer func() { w.commsLock <- struct{}{} }()
// Ensure the device isn't screwed with while user confirmation is pending
// TODO(karalabe): remove if hotplug lands on Windows
w.hub.commsLock.Lock()
w.hub.commsPend++
w.hub.commsLock.Unlock()
defer func() {
w.hub.commsLock.Lock()
w.hub.commsPend--
w.hub.commsLock.Unlock()
}()
return w.ledgerSign(path, account.Address, tx, chainID)
}
// SignHashWithPassphrase implements accounts.Wallet, however signing arbitrary
// data is not supported for Ledger wallets, so this method will always return
// an error.
func (w *ledgerWallet) SignHashWithPassphrase(account accounts.Account, passphrase string, hash []byte) ([]byte, error) {
return nil, accounts.ErrNotSupported
}
// SignTxWithPassphrase implements accounts.Wallet, attempting to sign the given
// transaction with the given account using passphrase as extra authentication.
// Since the Ledger does not support extra passphrases, it is silently ignored.
func (w *ledgerWallet) SignTxWithPassphrase(account accounts.Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
return w.SignTx(account, tx, chainID)
}
// ledgerVersion retrieves the current version of the Ethereum wallet app running
// on the Ledger wallet.
//
// The version retrieval protocol is defined as follows:
//
// CLA | INS | P1 | P2 | Lc | Le
// ----+-----+----+----+----+---
// E0 | 06 | 00 | 00 | 00 | 04
//
// With no input data, and the output data being:
//
// Description | Length
// ---------------------------------------------------+--------
// Flags 01: arbitrary data signature enabled by user | 1 byte
// Application major version | 1 byte
// Application minor version | 1 byte
// Application patch version | 1 byte
func (w *ledgerWallet) ledgerVersion() ([3]byte, error) {
// Send the request and wait for the response
reply, err := w.ledgerExchange(ledgerOpGetConfiguration, 0, 0, nil)
if err != nil {
return [3]byte{}, err
}
if len(reply) != 4 {
return [3]byte{}, errInvalidVersionReply
}
// Cache the version for future reference
var version [3]byte
copy(version[:], reply[1:])
return version, nil
}
// ledgerDerive retrieves the currently active Ethereum address from a Ledger
// wallet at the specified derivation path.
//
// The address derivation protocol is defined as follows:
//
// CLA | INS | P1 | P2 | Lc | Le
// ----+-----+----+----+-----+---
// E0 | 02 | 00 return address
// 01 display address and confirm before returning
// | 00: do not return the chain code
// | 01: return the chain code
// | var | 00
//
// Where the input data is:
//
// Description | Length
// -------------------------------------------------+--------
// Number of BIP 32 derivations to perform (max 10) | 1 byte
// First derivation index (big endian) | 4 bytes
// ... | 4 bytes
// Last derivation index (big endian) | 4 bytes
//
// And the output data is:
//
// Description | Length
// ------------------------+-------------------
// Public Key length | 1 byte
// Uncompressed Public Key | arbitrary
// Ethereum address length | 1 byte
// Ethereum address | 40 bytes hex ascii
// Chain code if requested | 32 bytes
func (w *ledgerWallet) ledgerDerive(derivationPath []uint32) (common.Address, error) {
// Flatten the derivation path into the Ledger request
path := make([]byte, 1+4*len(derivationPath))
path[0] = byte(len(derivationPath))
for i, component := range derivationPath {
binary.BigEndian.PutUint32(path[1+4*i:], component)
}
// Send the request and wait for the response
reply, err := w.ledgerExchange(ledgerOpRetrieveAddress, ledgerP1DirectlyFetchAddress, ledgerP2DiscardAddressChainCode, path)
if err != nil {
return common.Address{}, err
}
// Discard the public key, we don't need that for now
if len(reply) < 1 || len(reply) < 1+int(reply[0]) {
return common.Address{}, errors.New("reply lacks public key entry")
}
reply = reply[1+int(reply[0]):]
// Extract the Ethereum hex address string
if len(reply) < 1 || len(reply) < 1+int(reply[0]) {
return common.Address{}, errors.New("reply lacks address entry")
}
hexstr := reply[1 : 1+int(reply[0])]
// Decode the hex sting into an Ethereum address and return
var address common.Address
hex.Decode(address[:], hexstr)
return address, nil
}
// ledgerSign sends the transaction to the Ledger wallet, and waits for the user
// to confirm or deny the transaction.
//
// The transaction signing protocol is defined as follows:
//
// CLA | INS | P1 | P2 | Lc | Le
// ----+-----+----+----+-----+---
// E0 | 04 | 00: first transaction data block
// 80: subsequent transaction data block
// | 00 | variable | variable
//
// Where the input for the first transaction block (first 255 bytes) is:
//
// Description | Length
// -------------------------------------------------+----------
// Number of BIP 32 derivations to perform (max 10) | 1 byte
// First derivation index (big endian) | 4 bytes
// ... | 4 bytes
// Last derivation index (big endian) | 4 bytes
// RLP transaction chunk | arbitrary
//
// And the input for subsequent transaction blocks (first 255 bytes) are:
//
// Description | Length
// ----------------------+----------
// RLP transaction chunk | arbitrary
//
// And the output data is:
//
// Description | Length
// ------------+---------
// signature V | 1 byte
// signature R | 32 bytes
// signature S | 32 bytes
func (w *ledgerWallet) ledgerSign(derivationPath []uint32, address common.Address, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
// Flatten the derivation path into the Ledger request
path := make([]byte, 1+4*len(derivationPath))
path[0] = byte(len(derivationPath))
for i, component := range derivationPath {
binary.BigEndian.PutUint32(path[1+4*i:], component)
}
// Create the transaction RLP based on whether legacy or EIP155 signing was requeste
var (
txrlp []byte
err error
)
if chainID == nil {
if txrlp, err = rlp.EncodeToBytes([]interface{}{tx.Nonce(), tx.GasPrice(), tx.Gas(), tx.To(), tx.Value(), tx.Data()}); err != nil {
return nil, err
}
} else {
if txrlp, err = rlp.EncodeToBytes([]interface{}{tx.Nonce(), tx.GasPrice(), tx.Gas(), tx.To(), tx.Value(), tx.Data(), chainID, big.NewInt(0), big.NewInt(0)}); err != nil {
return nil, err
}
}
payload := append(path, txrlp...)
// Send the request and wait for the response
var (
op = ledgerP1InitTransactionData
reply []byte
)
for len(payload) > 0 {
// Calculate the size of the next data chunk
chunk := 255
if chunk > len(payload) {
chunk = len(payload)
}
// Send the chunk over, ensuring it's processed correctly
reply, err = w.ledgerExchange(ledgerOpSignTransaction, op, 0, payload[:chunk])
if err != nil {
return nil, err
}
// Shift the payload and ensure subsequent chunks are marked as such
payload = payload[chunk:]
op = ledgerP1ContTransactionData
}
// Extract the Ethereum signature and do a sanity validation
if len(reply) != 65 {
return nil, errors.New("reply lacks signature")
}
signature := append(reply[1:], reply[0])
// Create the correct signer and signature transform based on the chain ID
var signer types.Signer
if chainID == nil {
signer = new(types.HomesteadSigner)
} else {
signer = types.NewEIP155Signer(chainID)
signature[64] = signature[64] - byte(chainID.Uint64()*2+35)
}
// Inject the final signature into the transaction and sanity check the sender
signed, err := tx.WithSignature(signer, signature)
if err != nil {
return nil, err
}
sender, err := types.Sender(signer, signed)
if err != nil {
return nil, err
}
if sender != address {
return nil, fmt.Errorf("signer mismatch: expected %s, got %s", address.Hex(), sender.Hex())
}
return signed, nil
}
// ledgerExchange performs a data exchange with the Ledger wallet, sending it a
// message and retrieving the response.
//
// The common transport header is defined as follows:
//
// Description | Length
// --------------------------------------+----------
// Communication channel ID (big endian) | 2 bytes
// Command tag | 1 byte
// Packet sequence index (big endian) | 2 bytes
// Payload | arbitrary
//
// The Communication channel ID allows commands multiplexing over the same
// physical link. It is not used for the time being, and should be set to 0101
// to avoid compatibility issues with implementations ignoring a leading 00 byte.
//
// The Command tag describes the message content. Use TAG_APDU (0x05) for standard
// APDU payloads, or TAG_PING (0x02) for a simple link test.
//
// The Packet sequence index describes the current sequence for fragmented payloads.
// The first fragment index is 0x00.
//
// APDU Command payloads are encoded as follows:
//
// Description | Length
// -----------------------------------
// APDU length (big endian) | 2 bytes
// APDU CLA | 1 byte
// APDU INS | 1 byte
// APDU P1 | 1 byte
// APDU P2 | 1 byte
// APDU length | 1 byte
// Optional APDU data | arbitrary
func (w *ledgerWallet) ledgerExchange(opcode ledgerOpcode, p1 ledgerParam1, p2 ledgerParam2, data []byte) ([]byte, error) {
// Construct the message payload, possibly split into multiple chunks
apdu := make([]byte, 2, 7+len(data))
binary.BigEndian.PutUint16(apdu, uint16(5+len(data)))
apdu = append(apdu, []byte{0xe0, byte(opcode), byte(p1), byte(p2), byte(len(data))}...)
apdu = append(apdu, data...)
// Stream all the chunks to the device
header := []byte{0x01, 0x01, 0x05, 0x00, 0x00} // Channel ID and command tag appended
chunk := make([]byte, 64)
space := len(chunk) - len(header)
for i := 0; len(apdu) > 0; i++ {
// Construct the new message to stream
chunk = append(chunk[:0], header...)
binary.BigEndian.PutUint16(chunk[3:], uint16(i))
if len(apdu) > space {
chunk = append(chunk, apdu[:space]...)
apdu = apdu[space:]
} else {
chunk = append(chunk, apdu...)
apdu = nil
}
// Send over to the device
w.log.Trace("Data chunk sent to the Ledger", "chunk", hexutil.Bytes(chunk))
if _, err := w.device.Write(chunk); err != nil {
return nil, err
}
}
// Stream the reply back from the wallet in 64 byte chunks
var reply []byte
chunk = chunk[:64] // Yeah, we surely have enough space
for {
// Read the next chunk from the Ledger wallet
if _, err := io.ReadFull(w.device, chunk); err != nil {
return nil, err
}
w.log.Trace("Data chunk received from the Ledger", "chunk", hexutil.Bytes(chunk))
// Make sure the transport header matches
if chunk[0] != 0x01 || chunk[1] != 0x01 || chunk[2] != 0x05 {
return nil, errReplyInvalidHeader
}
// If it's the first chunk, retrieve the total message length
var payload []byte
if chunk[3] == 0x00 && chunk[4] == 0x00 {
reply = make([]byte, 0, int(binary.BigEndian.Uint16(chunk[5:7])))
payload = chunk[7:]
} else {
payload = chunk[5:]
}
// Append to the reply and stop when filled up
if left := cap(reply) - len(reply); left > len(payload) {
reply = append(reply, payload...)
} else {
reply = append(reply, payload[:left]...)
break
}
}
return reply[:len(reply)-2], nil
}

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@ -0,0 +1,330 @@
// 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 Trezor hardware
// wallets. The wire protocol spec can be found on the SatoshiLabs website:
// https://doc.satoshilabs.com/trezor-tech/api-protobuf.html
package usbwallet
import (
"encoding/binary"
"errors"
"fmt"
"io"
"math/big"
"github.com/ethereum/go-ethereum/accounts"
"github.com/ethereum/go-ethereum/accounts/usbwallet/internal/trezor"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/log"
"github.com/golang/protobuf/proto"
)
// ErrTrezorPINNeeded is returned if opening the trezor requires a PIN code. In
// this case, the calling application should display a pinpad and send back the
// encoded passphrase.
var ErrTrezorPINNeeded = errors.New("trezor: pin needed")
// errTrezorReplyInvalidHeader is the error message returned by a Trezor data exchange
// if the device replies with a mismatching header. This usually means the device
// is in browser mode.
var errTrezorReplyInvalidHeader = errors.New("trezor: invalid reply header")
// trezorDriver implements the communication with a Trezor hardware wallet.
type trezorDriver struct {
device io.ReadWriter // USB device connection to communicate through
version [3]uint32 // Current version of the Trezor firmware
label string // Current textual label of the Trezor device
pinwait bool // Flags whether the device is waiting for PIN entry
failure error // Any failure that would make the device unusable
log log.Logger // Contextual logger to tag the trezor with its id
}
// newTrezorDriver creates a new instance of a Trezor USB protocol driver.
func newTrezorDriver(logger log.Logger) driver {
return &trezorDriver{
log: logger,
}
}
// Status implements accounts.Wallet, always whether the Trezor is opened, closed
// or whether the Ethereum app was not started on it.
func (w *trezorDriver) Status() (string, error) {
if w.failure != nil {
return fmt.Sprintf("Failed: %v", w.failure), w.failure
}
if w.device == nil {
return "Closed", w.failure
}
if w.pinwait {
return fmt.Sprintf("Trezor v%d.%d.%d '%s' waiting for PIN", w.version[0], w.version[1], w.version[2], w.label), w.failure
}
return fmt.Sprintf("Trezor v%d.%d.%d '%s' online", w.version[0], w.version[1], w.version[2], w.label), w.failure
}
// Open implements usbwallet.driver, attempting to initialize the connection to
// the Trezor hardware wallet. Initializing the Trezor is a two phase operation:
// * The first phase is to initialize the connection and read the wallet's
// features. This phase is invoked is the provided passphrase is empty. The
// device will display the pinpad as a result and will return an appropriate
// error to notify the user that a second open phase is needed.
// * The second phase is to unlock access to the Trezor, which is done by the
// user actually providing a passphrase mapping a keyboard keypad to the pin
// number of the user (shuffled according to the pinpad displayed).
func (w *trezorDriver) Open(device io.ReadWriter, passphrase string) error {
w.device, w.failure = device, nil
// If phase 1 is requested, init the connection and wait for user callback
if passphrase == "" {
// If we're already waiting for a PIN entry, insta-return
if w.pinwait {
return ErrTrezorPINNeeded
}
// Initialize a connection to the device
features := new(trezor.Features)
if _, err := w.trezorExchange(&trezor.Initialize{}, features); err != nil {
return err
}
w.version = [3]uint32{features.GetMajorVersion(), features.GetMinorVersion(), features.GetPatchVersion()}
w.label = features.GetLabel()
// Do a manual ping, forcing the device to ask for its PIN
askPin := true
res, err := w.trezorExchange(&trezor.Ping{PinProtection: &askPin}, new(trezor.PinMatrixRequest), new(trezor.Success))
if err != nil {
return err
}
// Only return the PIN request if the device wasn't unlocked until now
if res == 1 {
return nil // Device responded with trezor.Success
}
w.pinwait = true
return ErrTrezorPINNeeded
}
// Phase 2 requested with actual PIN entry
w.pinwait = false
if _, err := w.trezorExchange(&trezor.PinMatrixAck{Pin: &passphrase}, new(trezor.Success)); err != nil {
w.failure = err
return err
}
return nil
}
// Close implements usbwallet.driver, cleaning up and metadata maintained within
// the Trezor driver.
func (w *trezorDriver) Close() error {
w.version, w.label, w.pinwait = [3]uint32{}, "", false
return nil
}
// Heartbeat implements usbwallet.driver, performing a sanity check against the
// Trezor to see if it's still online.
func (w *trezorDriver) Heartbeat() error {
if _, err := w.trezorExchange(&trezor.Ping{}, new(trezor.Success)); err != nil {
w.failure = err
return err
}
return nil
}
// Derive implements usbwallet.driver, sending a derivation request to the Trezor
// and returning the Ethereum address located on that derivation path.
func (w *trezorDriver) Derive(path accounts.DerivationPath) (common.Address, error) {
return w.trezorDerive(path)
}
// SignTx implements usbwallet.driver, sending the transaction to the Trezor and
// waiting for the user to confirm or deny the transaction.
func (w *trezorDriver) SignTx(path accounts.DerivationPath, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
if w.device == nil {
return common.Address{}, nil, accounts.ErrWalletClosed
}
return w.trezorSign(path, tx, chainID)
}
// trezorDerive sends a derivation request to the Trezor device and returns the
// Ethereum address located on that path.
func (w *trezorDriver) trezorDerive(derivationPath []uint32) (common.Address, error) {
address := new(trezor.EthereumAddress)
if _, err := w.trezorExchange(&trezor.EthereumGetAddress{AddressN: derivationPath}, address); err != nil {
return common.Address{}, err
}
return common.BytesToAddress(address.GetAddress()), nil
}
// trezorSign sends the transaction to the Trezor wallet, and waits for the user
// to confirm or deny the transaction.
func (w *trezorDriver) trezorSign(derivationPath []uint32, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
// Create the transaction initiation message
data := tx.Data()
length := uint32(len(data))
request := &trezor.EthereumSignTx{
AddressN: derivationPath,
Nonce: new(big.Int).SetUint64(tx.Nonce()).Bytes(),
GasPrice: tx.GasPrice().Bytes(),
GasLimit: tx.Gas().Bytes(),
Value: tx.Value().Bytes(),
DataLength: &length,
}
if to := tx.To(); to != nil {
request.To = (*to)[:] // Non contract deploy, set recipient explicitly
}
if length > 1024 { // Send the data chunked if that was requested
request.DataInitialChunk, data = data[:1024], data[1024:]
} else {
request.DataInitialChunk, data = data, nil
}
if chainID != nil { // EIP-155 transaction, set chain ID explicitly (only 32 bit is supported!?)
id := uint32(chainID.Int64())
request.ChainId = &id
}
// Send the initiation message and stream content until a signature is returned
response := new(trezor.EthereumTxRequest)
if _, err := w.trezorExchange(request, response); err != nil {
return common.Address{}, nil, err
}
for response.DataLength != nil && int(*response.DataLength) <= len(data) {
chunk := data[:*response.DataLength]
data = data[*response.DataLength:]
if _, err := w.trezorExchange(&trezor.EthereumTxAck{DataChunk: chunk}, response); err != nil {
return common.Address{}, nil, err
}
}
// Extract the Ethereum signature and do a sanity validation
if len(response.GetSignatureR()) == 0 || len(response.GetSignatureS()) == 0 || response.GetSignatureV() == 0 {
return common.Address{}, nil, errors.New("reply lacks signature")
}
signature := append(append(response.GetSignatureR(), response.GetSignatureS()...), byte(response.GetSignatureV()))
// Create the correct signer and signature transform based on the chain ID
var signer types.Signer
if chainID == nil {
signer = new(types.HomesteadSigner)
} else {
signer = types.NewEIP155Signer(chainID)
signature[64] = signature[64] - byte(chainID.Uint64()*2+35)
}
// Inject the final signature into the transaction and sanity check the sender
signed, err := tx.WithSignature(signer, signature)
if err != nil {
return common.Address{}, nil, err
}
sender, err := types.Sender(signer, signed)
if err != nil {
return common.Address{}, nil, err
}
return sender, signed, nil
}
// trezorExchange performs a data exchange with the Trezor wallet, sending it a
// message and retrieving the response. If multiple responses are possible, the
// method will also return the index of the destination object used.
func (w *trezorDriver) trezorExchange(req proto.Message, results ...proto.Message) (int, error) {
// Construct the original message payload to chunk up
data, err := proto.Marshal(req)
if err != nil {
return 0, err
}
payload := make([]byte, 8+len(data))
copy(payload, []byte{0x23, 0x23})
binary.BigEndian.PutUint16(payload[2:], trezor.Type(req))
binary.BigEndian.PutUint32(payload[4:], uint32(len(data)))
copy(payload[8:], data)
// Stream all the chunks to the device
chunk := make([]byte, 64)
chunk[0] = 0x3f // Report ID magic number
for len(payload) > 0 {
// Construct the new message to stream, padding with zeroes if needed
if len(payload) > 63 {
copy(chunk[1:], payload[:63])
payload = payload[63:]
} else {
copy(chunk[1:], payload)
copy(chunk[1+len(payload):], make([]byte, 63-len(payload)))
payload = nil
}
// Send over to the device
w.log.Trace("Data chunk sent to the Trezor", "chunk", hexutil.Bytes(chunk))
if _, err := w.device.Write(chunk); err != nil {
return 0, err
}
}
// Stream the reply back from the wallet in 64 byte chunks
var (
kind uint16
reply []byte
)
for {
// Read the next chunk from the Trezor wallet
if _, err := io.ReadFull(w.device, chunk); err != nil {
return 0, err
}
w.log.Trace("Data chunk received from the Trezor", "chunk", hexutil.Bytes(chunk))
// Make sure the transport header matches
if chunk[0] != 0x3f || (len(reply) == 0 && (chunk[1] != 0x23 || chunk[2] != 0x23)) {
return 0, errTrezorReplyInvalidHeader
}
// If it's the first chunk, retrieve the reply message type and total message length
var payload []byte
if len(reply) == 0 {
kind = binary.BigEndian.Uint16(chunk[3:5])
reply = make([]byte, 0, int(binary.BigEndian.Uint32(chunk[5:9])))
payload = chunk[9:]
} else {
payload = chunk[1:]
}
// Append to the reply and stop when filled up
if left := cap(reply) - len(reply); left > len(payload) {
reply = append(reply, payload...)
} else {
reply = append(reply, payload[:left]...)
break
}
}
// Try to parse the reply into the requested reply message
if kind == uint16(trezor.MessageType_MessageType_Failure) {
// Trezor returned a failure, extract and return the message
failure := new(trezor.Failure)
if err := proto.Unmarshal(reply, failure); err != nil {
return 0, err
}
return 0, errors.New("trezor: " + failure.GetMessage())
}
if kind == uint16(trezor.MessageType_MessageType_ButtonRequest) {
// Trezor is waiting for user confirmation, ack and wait for the next message
return w.trezorExchange(&trezor.ButtonAck{}, results...)
}
for i, res := range results {
if trezor.Type(res) == kind {
return i, proto.Unmarshal(reply, res)
}
}
expected := make([]string, len(results))
for i, res := range results {
expected[i] = trezor.Name(trezor.Type(res))
}
return 0, fmt.Errorf("trezor: expected reply types %s, got %s", expected, trezor.Name(kind))
}

View File

@ -1,210 +0,0 @@
// 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/>.
package usbwallet
import (
"errors"
"runtime"
"sync"
"time"
"github.com/ethereum/go-ethereum/accounts"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/log"
"github.com/karalabe/hid"
)
// TrezorScheme is the protocol scheme prefixing account and wallet URLs.
var TrezorScheme = "trezor"
// trezorVendorID is the USB vendor ID for SatoshiLabs.
var trezorVendorID = uint16(0x534c)
// trezorDeviceID is the USB device ID for the Trezor 1.
var trezorDeviceID = uint16(0x0001)
// Maximum time between wallet refreshes (if USB hotplug notifications don't work).
const trezorRefreshCycle = time.Second
// Minimum time between wallet refreshes to avoid USB trashing.
const trezorRefreshThrottling = 500 * time.Millisecond
// TrezorHub is a accounts.Backend that can find and handle Trezor hardware wallets.
type TrezorHub struct {
refreshed time.Time // Time instance when the list of wallets was last refreshed
wallets []accounts.Wallet // List of Trezor 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
stateLock sync.RWMutex // Protects the internals of the hub from racey access
// TODO(karalabe): remove if hotplug lands on Windows
commsPend int // Number of operations blocking enumeration
commsLock sync.Mutex // Lock protecting the pending counter and enumeration
}
// NewTrezorHub creates a new hardware wallet manager for Trezor devices.
func NewTrezorHub() (*TrezorHub, error) {
if !hid.Supported() {
return nil, errors.New("unsupported platform")
}
hub := &TrezorHub{
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 Trezor hardware wallets.
func (hub *TrezorHub) Wallets() []accounts.Wallet {
// Make sure the list of wallets is up to date
hub.refreshWallets()
hub.stateLock.RLock()
defer hub.stateLock.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 *TrezorHub) refreshWallets() {
// Don't scan the USB like crazy it the user fetches wallets in a loop
hub.stateLock.RLock()
elapsed := time.Since(hub.refreshed)
hub.stateLock.RUnlock()
if elapsed < trezorRefreshThrottling {
return
}
// Retrieve the current list of Trezor devices
var trezors []hid.DeviceInfo
if runtime.GOOS == "linux" {
// hidapi on Linux opens the device during enumeration to retrieve some infos,
// breaking the Trezor protocol if that is waiting for user confirmation. This
// is a bug acknowledged at Trezor, but it won't be fixed on old devices so we
// need to prevent concurrent comms ourselves. The more elegant solution would
// be to ditch enumeration in favor of hutplug events, but that don't work yet
// on Windows so if we need to hack it anyway, this is more elegant for now.
hub.commsLock.Lock()
if hub.commsPend > 0 { // A confirmation is pending, don't refresh
hub.commsLock.Unlock()
return
}
}
for _, info := range hid.Enumerate(trezorVendorID, trezorDeviceID) {
if info.Interface == 0 { // interface #1 is the debug link, skip it
trezors = append(trezors, info)
}
}
if runtime.GOOS == "linux" {
// See rationale before the enumeration why this is needed and only on Linux.
hub.commsLock.Unlock()
}
// Transform the current list of wallets into the new one
hub.stateLock.Lock()
wallets := make([]accounts.Wallet, 0, len(trezors))
events := []accounts.WalletEvent{}
for _, trezor := range trezors {
url := accounts.URL{Scheme: TrezorScheme, Path: trezor.Path}
// 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].(*trezorWallet).failed()) {
events = append(events, accounts.WalletEvent{Wallet: hub.wallets[0], Kind: accounts.WalletDropped})
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 := &trezorWallet{hub: hub, url: &url, info: trezor, log: log.New("url", url)}
events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletArrived})
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, Kind: accounts.WalletDropped})
}
hub.refreshed = time.Now()
hub.wallets = wallets
hub.stateLock.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 Trezor wallets.
func (hub *TrezorHub) Subscribe(sink chan<- accounts.WalletEvent) event.Subscription {
// We need the mutex to reliably start/stop the update loop
hub.stateLock.Lock()
defer hub.stateLock.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 *TrezorHub) 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(trezorRefreshCycle):
}
// Run the wallet refresher
hub.refreshWallets()
// If all our subscribers left, stop the updater
hub.stateLock.Lock()
if hub.updateScope.Count() == 0 {
hub.updating = false
hub.stateLock.Unlock()
return
}
hub.stateLock.Unlock()
}
}

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@ -1,761 +0,0 @@
// 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 Trezor hardware
// wallets. The wire protocol spec can be found on the SatoshiLabs website:
// https://doc.satoshilabs.com/trezor-tech/api-protobuf.html
package usbwallet
import (
"context"
"encoding/binary"
"errors"
"fmt"
"io"
"math/big"
"sync"
"time"
ethereum "github.com/ethereum/go-ethereum"
"github.com/ethereum/go-ethereum/accounts"
"github.com/ethereum/go-ethereum/accounts/usbwallet/internal/trezor"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/log"
"github.com/golang/protobuf/proto"
"github.com/karalabe/hid"
)
// ErrTrezorPINNeeded is returned if opening the trezor requires a PIN code. In
// this case, the calling application should display a pinpad and send back the
// encoded passphrase.
var ErrTrezorPINNeeded = errors.New("trezor: pin needed")
// trezorWallet represents a live USB Trezor hardware wallet.
type trezorWallet struct {
hub *TrezorHub // USB hub the device originates from (TODO(karalabe): remove if hotplug lands on Windows)
url *accounts.URL // Textual URL uniquely identifying this wallet
info hid.DeviceInfo // Known USB device infos about the wallet
device *hid.Device // USB device advertising itself as a Trezor wallet
failure error // Any failure that would make the device unusable
version [3]uint32 // Current version of the Trezor formware (zero if app is offline)
label string // Current textual label of the Trezor device
pinwait bool // Flags whether the device is waiting for PIN entry
accounts []accounts.Account // List of derive accounts pinned on the Trezor
paths map[common.Address]accounts.DerivationPath // Known derivation paths for signing operations
deriveNextPath accounts.DerivationPath // Next derivation path for account auto-discovery
deriveNextAddr common.Address // Next derived account address for auto-discovery
deriveChain ethereum.ChainStateReader // Blockchain state reader to discover used account with
deriveReq chan chan struct{} // Channel to request a self-derivation on
deriveQuit chan chan error // Channel to terminate the self-deriver with
healthQuit chan chan error
// Locking a hardware wallet is a bit special. Since hardware devices are lower
// performing, any communication with them might take a non negligible amount of
// time. Worse still, waiting for user confirmation can take arbitrarily long,
// but exclusive communication must be upheld during. Locking the entire wallet
// in the mean time however would stall any parts of the system that don't want
// to communicate, just read some state (e.g. list the accounts).
//
// As such, a hardware wallet needs two locks to function correctly. A state
// lock can be used to protect the wallet's software-side internal state, which
// must not be held exlusively during hardware communication. A communication
// lock can be used to achieve exclusive access to the device itself, this one
// however should allow "skipping" waiting for operations that might want to
// use the device, but can live without too (e.g. account self-derivation).
//
// Since we have two locks, it's important to know how to properly use them:
// - Communication requires the `device` to not change, so obtaining the
// commsLock should be done after having a stateLock.
// - Communication must not disable read access to the wallet state, so it
// must only ever hold a *read* lock to stateLock.
commsLock chan struct{} // Mutex (buf=1) for the USB comms without keeping the state locked
stateLock sync.RWMutex // Protects read and write access to the wallet struct fields
log log.Logger // Contextual logger to tag the trezor with its id
}
// URL implements accounts.Wallet, returning the URL of the Trezor device.
func (w *trezorWallet) URL() accounts.URL {
return *w.url // Immutable, no need for a lock
}
// Status implements accounts.Wallet, always whether the Trezor is opened, closed
// or whether the Ethereum app was not started on it.
func (w *trezorWallet) Status() string {
w.stateLock.RLock() // No device communication, state lock is enough
defer w.stateLock.RUnlock()
if w.failure != nil {
return fmt.Sprintf("Failed: %v", w.failure)
}
if w.device == nil {
return "Closed"
}
if w.pinwait {
return fmt.Sprintf("Trezor v%d.%d.%d '%s' waiting for PIN", w.version[0], w.version[1], w.version[2], w.label)
}
return fmt.Sprintf("Trezor v%d.%d.%d '%s' online", w.version[0], w.version[1], w.version[2], w.label)
}
// failed returns if the USB device wrapped by the wallet failed for some reason.
// This is used by the device scanner to report failed wallets as departed.
//
// The method assumes that the state lock is *not* held!
func (w *trezorWallet) failed() bool {
w.stateLock.RLock() // No device communication, state lock is enough
defer w.stateLock.RUnlock()
return w.failure != nil
}
// Open implements accounts.Wallet, attempting to open a USB connection to the
// Trezor hardware wallet. Connecting to the Trezor is a two phase operation:
// * The first phase is to establish the USB connection, initialize it and read
// the wallet's features. This phase is invoked is the provided passphrase is
// empty. The device will display the pinpad as a result and will return an
// appropriate error to notify the user that a second open phase is needed.
// * The second phase is to unlock access to the Trezor, which is done by the
// user actually providing a passphrase mapping a keyboard keypad to the pin
// number of the user (shuffled according to the pinpad displayed).
func (w *trezorWallet) Open(passphrase string) error {
w.stateLock.Lock() // State lock is enough since there's no connection yet at this point
defer w.stateLock.Unlock()
// If phase 1 is requested, init the connection and wait for user callback
if passphrase == "" {
// If we're already waiting for a PIN entry, insta-return
if w.pinwait {
return ErrTrezorPINNeeded
}
// Initialize a connection to the device
if err := w.openInit(); err != nil {
return err
}
// Do a manual ping, forcing the device to ask for its PIN
askPin, pinRequest := true, new(trezor.PinMatrixRequest)
if err := w.trezorExchange(&trezor.Ping{PinProtection: &askPin}, pinRequest); err != nil {
return err
}
w.pinwait = true
return ErrTrezorPINNeeded
}
// Phase 2 requested with actual PIN entry
w.pinwait = false
success := new(trezor.Success)
if err := w.trezorExchange(&trezor.PinMatrixAck{Pin: &passphrase}, success); err != nil {
w.failure = err
return err
}
go w.hub.updateFeed.Send(accounts.WalletEvent{Wallet: w, Kind: accounts.WalletOpened})
// Trezor unlocked, start the heartbeat cycle and account derivation
w.paths = make(map[common.Address]accounts.DerivationPath)
w.deriveReq = make(chan chan struct{})
w.deriveQuit = make(chan chan error)
w.healthQuit = make(chan chan error)
defer func() {
go w.heartbeat()
go w.selfDerive()
}()
return nil
}
// openInit is the first phase of a Trezor opening mechanism which initializes
// device connection and requests the device to display the pinpad.
func (w *trezorWallet) openInit() error {
// If the wallet was already opened, don't try to phase-1 open again
if w.device != nil {
return accounts.ErrWalletAlreadyOpen
}
// Otherwise iterate over all USB devices and find this again (no way to directly do this)
device, err := w.info.Open()
if err != nil {
return err
}
// Wallet successfully connected to, init the connection and start the heartbeat
w.device = device
w.commsLock = make(chan struct{}, 1)
w.commsLock <- struct{}{} // Enable lock
// Retrieve the Trezor's version number and user label
features := new(trezor.Features)
if err := w.trezorExchange(&trezor.Initialize{}, features); err != nil {
return err
}
w.version = [3]uint32{features.GetMajorVersion(), features.GetMinorVersion(), features.GetPatchVersion()}
w.label = features.GetLabel()
return nil
}
// heartbeat is a health check loop for the Trezor wallets to periodically verify
// whether they are still present or if they malfunctioned. It is needed because:
// - libusb on Windows doesn't support hotplug, so we can't detect USB unplugs
func (w *trezorWallet) heartbeat() {
w.log.Debug("Trezor health-check started")
defer w.log.Debug("Trezor health-check stopped")
// Execute heartbeat checks until termination or error
var (
errc chan error
err error
)
for errc == nil && err == nil {
// Wait until termination is requested or the heartbeat cycle arrives
select {
case errc = <-w.healthQuit:
// Termination requested
continue
case <-time.After(heartbeatCycle):
// Heartbeat time
}
// Execute a tiny data exchange to see responsiveness
w.stateLock.RLock()
if w.device == nil {
// Terminated while waiting for the lock
w.stateLock.RUnlock()
continue
}
<-w.commsLock // Don't lock state while executing ping
success := new(trezor.Success)
err = w.trezorExchange(&trezor.Ping{}, success)
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
if err != nil {
w.stateLock.Lock() // Lock state to tear the wallet down
w.failure = err
w.close()
w.stateLock.Unlock()
}
// Ignore non hardware related errors
err = nil
}
// In case of error, wait for termination
if err != nil {
w.log.Debug("Trezor health-check failed", "err", err)
errc = <-w.healthQuit
}
errc <- err
}
// Close implements accounts.Wallet, closing the USB connection to the Trezor.
func (w *trezorWallet) Close() error {
// Ensure the wallet was opened
w.stateLock.RLock()
hQuit, dQuit := w.healthQuit, w.deriveQuit
w.stateLock.RUnlock()
// Terminate the health checks
var herr error
if hQuit != nil {
errc := make(chan error)
hQuit <- errc
herr = <-errc // Save for later, we *must* close the USB
}
// Terminate the self-derivations
var derr error
if dQuit != nil {
errc := make(chan error)
dQuit <- errc
derr = <-errc // Save for later, we *must* close the USB
}
// Terminate the device connection
w.stateLock.Lock()
defer w.stateLock.Unlock()
w.healthQuit = nil
w.deriveQuit = nil
w.deriveReq = nil
if err := w.close(); err != nil {
return err
}
if herr != nil {
return herr
}
return derr
}
// close is the internal wallet closer that terminates the USB connection and
// resets all the fields to their defaults.
//
// Note, close assumes the state lock is held!
func (w *trezorWallet) close() error {
// Allow duplicate closes, especially for health-check failures
if w.device == nil {
return nil
}
// Close the device, clear everything, then return
w.device.Close()
w.device = nil
w.label, w.version = "", [3]uint32{}
w.accounts, w.paths = nil, nil
return nil
}
// Accounts implements accounts.Wallet, returning the list of accounts pinned to
// the Trezor hardware wallet. If self-derivation was enabled, the account list
// is periodically expanded based on current chain state.
func (w *trezorWallet) Accounts() []accounts.Account {
// Attempt self-derivation if it's running
reqc := make(chan struct{}, 1)
select {
case w.deriveReq <- reqc:
// Self-derivation request accepted, wait for it
<-reqc
default:
// Self-derivation offline, throttled or busy, skip
}
// Return whatever account list we ended up with
w.stateLock.RLock()
defer w.stateLock.RUnlock()
cpy := make([]accounts.Account, len(w.accounts))
copy(cpy, w.accounts)
return cpy
}
// selfDerive is an account derivation loop that upon request attempts to find
// new non-zero accounts.
func (w *trezorWallet) selfDerive() {
w.log.Debug("Trezor self-derivation started")
defer w.log.Debug("Trezor self-derivation stopped")
// Execute self-derivations until termination or error
var (
reqc chan struct{}
errc chan error
err error
)
for errc == nil && err == nil {
// Wait until either derivation or termination is requested
select {
case errc = <-w.deriveQuit:
// Termination requested
continue
case reqc = <-w.deriveReq:
// Account discovery requested
}
// Derivation needs a chain and device access, skip if either unavailable
w.stateLock.RLock()
if w.device == nil || w.deriveChain == nil {
w.stateLock.RUnlock()
reqc <- struct{}{}
continue
}
select {
case <-w.commsLock:
default:
w.stateLock.RUnlock()
reqc <- struct{}{}
continue
}
// Device lock obtained, derive the next batch of accounts
var (
accs []accounts.Account
paths []accounts.DerivationPath
nextAddr = w.deriveNextAddr
nextPath = w.deriveNextPath
context = context.Background()
)
for empty := false; !empty; {
// Retrieve the next derived Ethereum account
if nextAddr == (common.Address{}) {
if nextAddr, err = w.trezorDerive(nextPath); err != nil {
w.log.Warn("Trezor account derivation failed", "err", err)
break
}
}
// Check the account's status against the current chain state
var (
balance *big.Int
nonce uint64
)
balance, err = w.deriveChain.BalanceAt(context, nextAddr, nil)
if err != nil {
w.log.Warn("Trezor balance retrieval failed", "err", err)
break
}
nonce, err = w.deriveChain.NonceAt(context, nextAddr, nil)
if err != nil {
w.log.Warn("Trezor nonce retrieval failed", "err", err)
break
}
// If the next account is empty, stop self-derivation, but add it nonetheless
if balance.Sign() == 0 && nonce == 0 {
empty = true
}
// We've just self-derived a new account, start tracking it locally
path := make(accounts.DerivationPath, len(nextPath))
copy(path[:], nextPath[:])
paths = append(paths, path)
account := accounts.Account{
Address: nextAddr,
URL: accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)},
}
accs = append(accs, account)
// Display a log message to the user for new (or previously empty accounts)
if _, known := w.paths[nextAddr]; !known || (!empty && nextAddr == w.deriveNextAddr) {
w.log.Info("Trezor discovered new account", "address", nextAddr, "path", path, "balance", balance, "nonce", nonce)
}
// Fetch the next potential account
if !empty {
nextAddr = common.Address{}
nextPath[len(nextPath)-1]++
}
}
// Self derivation complete, release device lock
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
// Insert any accounts successfully derived
w.stateLock.Lock()
for i := 0; i < len(accs); i++ {
if _, ok := w.paths[accs[i].Address]; !ok {
w.accounts = append(w.accounts, accs[i])
w.paths[accs[i].Address] = paths[i]
}
}
// Shift the self-derivation forward
// TODO(karalabe): don't overwrite changes from wallet.SelfDerive
w.deriveNextAddr = nextAddr
w.deriveNextPath = nextPath
w.stateLock.Unlock()
// Notify the user of termination and loop after a bit of time (to avoid trashing)
reqc <- struct{}{}
if err == nil {
select {
case errc = <-w.deriveQuit:
// Termination requested, abort
case <-time.After(selfDeriveThrottling):
// Waited enough, willing to self-derive again
}
}
}
// In case of error, wait for termination
if err != nil {
w.log.Debug("Trezor self-derivation failed", "err", err)
errc = <-w.deriveQuit
}
errc <- err
}
// Contains implements accounts.Wallet, returning whether a particular account is
// or is not pinned into this Trezor instance. Although we could attempt to resolve
// unpinned accounts, that would be an non-negligible hardware operation.
func (w *trezorWallet) Contains(account accounts.Account) bool {
w.stateLock.RLock()
defer w.stateLock.RUnlock()
_, exists := w.paths[account.Address]
return exists
}
// Derive implements accounts.Wallet, deriving a new account at the specific
// derivation path. If pin is set to true, the account will be added to the list
// of tracked accounts.
func (w *trezorWallet) Derive(path accounts.DerivationPath, pin bool) (accounts.Account, error) {
// Try to derive the actual account and update its URL if successful
w.stateLock.RLock() // Avoid device disappearing during derivation
if w.device == nil {
w.stateLock.RUnlock()
return accounts.Account{}, accounts.ErrWalletClosed
}
<-w.commsLock // Avoid concurrent hardware access
address, err := w.trezorDerive(path)
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
// If an error occurred or no pinning was requested, return
if err != nil {
return accounts.Account{}, err
}
account := accounts.Account{
Address: address,
URL: accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)},
}
if !pin {
return account, nil
}
// Pinning needs to modify the state
w.stateLock.Lock()
defer w.stateLock.Unlock()
if _, ok := w.paths[address]; !ok {
w.accounts = append(w.accounts, account)
w.paths[address] = path
}
return account, nil
}
// SelfDerive implements accounts.Wallet, trying to discover accounts that the
// user used previously (based on the chain state), but ones that he/she did not
// explicitly pin to the wallet manually. To avoid chain head monitoring, self
// derivation only runs during account listing (and even then throttled).
func (w *trezorWallet) SelfDerive(base accounts.DerivationPath, chain ethereum.ChainStateReader) {
w.stateLock.Lock()
defer w.stateLock.Unlock()
w.deriveNextPath = make(accounts.DerivationPath, len(base))
copy(w.deriveNextPath[:], base[:])
w.deriveNextAddr = common.Address{}
w.deriveChain = chain
}
// SignHash implements accounts.Wallet, however signing arbitrary data is not
// supported for Trezor wallets, so this method will always return an error.
func (w *trezorWallet) SignHash(acc accounts.Account, hash []byte) ([]byte, error) {
return nil, accounts.ErrNotSupported
}
// SignTx implements accounts.Wallet. It sends the transaction over to the Trezor
// wallet to request a confirmation from the user. It returns either the signed
// transaction or a failure if the user denied the transaction.
func (w *trezorWallet) SignTx(account accounts.Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
w.stateLock.RLock() // Comms have own mutex, this is for the state fields
defer w.stateLock.RUnlock()
// If the wallet is closed, abort
if w.device == nil {
return nil, accounts.ErrWalletClosed
}
// Make sure the requested account is contained within
path, ok := w.paths[account.Address]
if !ok {
return nil, accounts.ErrUnknownAccount
}
// All infos gathered and metadata checks out, request signing
<-w.commsLock
defer func() { w.commsLock <- struct{}{} }()
// Ensure the device isn't screwed with while user confirmation is pending
// TODO(karalabe): remove if hotplug lands on Windows
w.hub.commsLock.Lock()
w.hub.commsPend++
w.hub.commsLock.Unlock()
defer func() {
w.hub.commsLock.Lock()
w.hub.commsPend--
w.hub.commsLock.Unlock()
}()
return w.trezorSign(path, account.Address, tx, chainID)
}
// SignHashWithPassphrase implements accounts.Wallet, however signing arbitrary
// data is not supported for Trezor wallets, so this method will always return
// an error.
func (w *trezorWallet) SignHashWithPassphrase(account accounts.Account, passphrase string, hash []byte) ([]byte, error) {
return nil, accounts.ErrNotSupported
}
// SignTxWithPassphrase implements accounts.Wallet, attempting to sign the given
// transaction with the given account using passphrase as extra authentication.
// Since the Trezor does not support extra passphrases, it is silently ignored.
func (w *trezorWallet) SignTxWithPassphrase(account accounts.Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
return w.SignTx(account, tx, chainID)
}
// trezorDerive sends a derivation request to the Trezor device and returns the
// Ethereum address located on that path.
func (w *trezorWallet) trezorDerive(derivationPath []uint32) (common.Address, error) {
address := new(trezor.EthereumAddress)
if err := w.trezorExchange(&trezor.EthereumGetAddress{AddressN: derivationPath}, address); err != nil {
return common.Address{}, err
}
return common.BytesToAddress(address.GetAddress()), nil
}
// trezorSign sends the transaction to the Trezor wallet, and waits for the user
// to confirm or deny the transaction.
func (w *trezorWallet) trezorSign(derivationPath []uint32, address common.Address, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
// Create the transaction initiation message
data := tx.Data()
length := uint32(len(data))
request := &trezor.EthereumSignTx{
AddressN: derivationPath,
Nonce: new(big.Int).SetUint64(tx.Nonce()).Bytes(),
GasPrice: tx.GasPrice().Bytes(),
GasLimit: tx.Gas().Bytes(),
Value: tx.Value().Bytes(),
DataLength: &length,
}
if to := tx.To(); to != nil {
request.To = (*to)[:] // Non contract deploy, set recipient explicitly
}
if length > 1024 { // Send the data chunked if that was requested
request.DataInitialChunk, data = data[:1024], data[1024:]
} else {
request.DataInitialChunk, data = data, nil
}
if chainID != nil { // EIP-155 transaction, set chain ID explicitly (only 32 bit is supported!?)
id := uint32(chainID.Int64())
request.ChainId = &id
}
// Send the initiation message and stream content until a signature is returned
response := new(trezor.EthereumTxRequest)
if err := w.trezorExchange(request, response); err != nil {
return nil, err
}
for response.DataLength != nil && int(*response.DataLength) <= len(data) {
chunk := data[:*response.DataLength]
data = data[*response.DataLength:]
if err := w.trezorExchange(&trezor.EthereumTxAck{DataChunk: chunk}, response); err != nil {
return nil, err
}
}
// Extract the Ethereum signature and do a sanity validation
if len(response.GetSignatureR()) == 0 || len(response.GetSignatureS()) == 0 || response.GetSignatureV() == 0 {
return nil, errors.New("reply lacks signature")
}
signature := append(append(response.GetSignatureR(), response.GetSignatureS()...), byte(response.GetSignatureV()))
// Create the correct signer and signature transform based on the chain ID
var signer types.Signer
if chainID == nil {
signer = new(types.HomesteadSigner)
} else {
signer = types.NewEIP155Signer(chainID)
signature[64] = signature[64] - byte(chainID.Uint64()*2+35)
}
// Inject the final signature into the transaction and sanity check the sender
signed, err := tx.WithSignature(signer, signature)
if err != nil {
return nil, err
}
sender, err := types.Sender(signer, signed)
if err != nil {
return nil, err
}
if sender != address {
return nil, fmt.Errorf("signer mismatch: expected %s, got %s", address.Hex(), sender.Hex())
}
return signed, nil
}
// trezorExchange performs a data exchange with the Trezor wallet, sending it a
// message and retrieving the response.
func (w *trezorWallet) trezorExchange(req proto.Message, res proto.Message) error {
// Construct the original message payload to chunk up
data, err := proto.Marshal(req)
if err != nil {
return err
}
payload := make([]byte, 8+len(data))
copy(payload, []byte{0x23, 0x23})
binary.BigEndian.PutUint16(payload[2:], trezor.Type(req))
binary.BigEndian.PutUint32(payload[4:], uint32(len(data)))
copy(payload[8:], data)
// Stream all the chunks to the device
chunk := make([]byte, 64)
chunk[0] = 0x3f // Report ID magic number
for len(payload) > 0 {
// Construct the new message to stream, padding with zeroes if needed
if len(payload) > 63 {
copy(chunk[1:], payload[:63])
payload = payload[63:]
} else {
copy(chunk[1:], payload)
copy(chunk[1+len(payload):], make([]byte, 63-len(payload)))
payload = nil
}
// Send over to the device
w.log.Trace("Data chunk sent to the Trezor", "chunk", hexutil.Bytes(chunk))
if _, err := w.device.Write(chunk); err != nil {
return err
}
}
// Stream the reply back from the wallet in 64 byte chunks
var (
kind uint16
reply []byte
)
for {
// Read the next chunk from the Trezor wallet
if _, err := io.ReadFull(w.device, chunk); err != nil {
return err
}
w.log.Trace("Data chunk received from the Trezor", "chunk", hexutil.Bytes(chunk))
// Make sure the transport header matches
if chunk[0] != 0x3f || (len(reply) == 0 && (chunk[1] != 0x23 || chunk[2] != 0x23)) {
return errReplyInvalidHeader
}
// If it's the first chunk, retrieve the reply message type and total message length
var payload []byte
if len(reply) == 0 {
kind = binary.BigEndian.Uint16(chunk[3:5])
reply = make([]byte, 0, int(binary.BigEndian.Uint32(chunk[5:9])))
payload = chunk[9:]
} else {
payload = chunk[1:]
}
// Append to the reply and stop when filled up
if left := cap(reply) - len(reply); left > len(payload) {
reply = append(reply, payload...)
} else {
reply = append(reply, payload[:left]...)
break
}
}
// Try to parse the reply into the requested reply message
if kind == uint16(trezor.MessageType_MessageType_Failure) {
// Trezor returned a failure, extract and return the message
failure := new(trezor.Failure)
if err := proto.Unmarshal(reply, failure); err != nil {
return err
}
return errors.New("trezor: " + failure.GetMessage())
}
if kind == uint16(trezor.MessageType_MessageType_ButtonRequest) {
// Trezor is waitinf for user confirmation, ack and wait for the next message
return w.trezorExchange(&trezor.ButtonAck{}, res)
}
if want := trezor.Type(res); kind != want {
return fmt.Errorf("trezor: expected reply type %s, got %s", trezor.Name(want), trezor.Name(kind))
}
return proto.Unmarshal(reply, res)
}

View File

@ -1,34 +0,0 @@
// 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/>.
// Package usbwallet implements support for USB hardware wallets.
package usbwallet
import "time"
// deviceID is a combined vendor/product identifier to uniquely identify a USB
// hardware device.
type deviceID struct {
Vendor uint16 // The Vendor identifer
Product uint16 // The Product identifier
}
// Maximum time between wallet health checks to detect USB unplugs.
const heartbeatCycle = time.Second
// Minimum time to wait between self derivation attempts, even it the user is
// requesting accounts like crazy.
const selfDeriveThrottling = time.Second

View File

@ -0,0 +1,562 @@
// 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/>.
// Package usbwallet implements support for USB hardware wallets.
package usbwallet
import (
"context"
"fmt"
"io"
"math/big"
"sync"
"time"
ethereum "github.com/ethereum/go-ethereum"
"github.com/ethereum/go-ethereum/accounts"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/log"
"github.com/karalabe/hid"
)
// Maximum time between wallet health checks to detect USB unplugs.
const heartbeatCycle = time.Second
// Minimum time to wait between self derivation attempts, even it the user is
// requesting accounts like crazy.
const selfDeriveThrottling = time.Second
// driver defines the vendor specific functionality hardware wallets instances
// must implement to allow using them with the wallet lifecycle management.
type driver interface {
// Status returns a textual status to aid the user in the current state of the
// wallet. It also returns an error indicating any failure the wallet might have
// encountered.
Status() (string, error)
// Open initializes access to a wallet instance. The passphrase parameter may
// or may not be used by the implementation of a particular wallet instance.
Open(device io.ReadWriter, passphrase string) error
// Close releases any resources held by an open wallet instance.
Close() error
// Heartbeat performs a sanity check against the hardware wallet to see if it
// is still online and healthy.
Heartbeat() error
// Derive sends a derivation request to the USB device and returns the Ethereum
// address located on that path.
Derive(path accounts.DerivationPath) (common.Address, error)
// SignTx sends the transaction to the USB device and waits for the user to confirm
// or deny the transaction.
SignTx(path accounts.DerivationPath, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error)
}
// wallet represents the common functionality shared by all USB hardware
// wallets to prevent reimplementing the same complex maintenance mechanisms
// for different vendors.
type wallet struct {
hub *Hub // USB hub scanning
driver driver // Hardware implementation of the low level device operations
url *accounts.URL // Textual URL uniquely identifying this wallet
info hid.DeviceInfo // Known USB device infos about the wallet
device *hid.Device // USB device advertising itself as a hardware wallet
accounts []accounts.Account // List of derive accounts pinned on the hardware wallet
paths map[common.Address]accounts.DerivationPath // Known derivation paths for signing operations
deriveNextPath accounts.DerivationPath // Next derivation path for account auto-discovery
deriveNextAddr common.Address // Next derived account address for auto-discovery
deriveChain ethereum.ChainStateReader // Blockchain state reader to discover used account with
deriveReq chan chan struct{} // Channel to request a self-derivation on
deriveQuit chan chan error // Channel to terminate the self-deriver with
healthQuit chan chan error
// Locking a hardware wallet is a bit special. Since hardware devices are lower
// performing, any communication with them might take a non negligible amount of
// time. Worse still, waiting for user confirmation can take arbitrarily long,
// but exclusive communication must be upheld during. Locking the entire wallet
// in the mean time however would stall any parts of the system that don't want
// to communicate, just read some state (e.g. list the accounts).
//
// As such, a hardware wallet needs two locks to function correctly. A state
// lock can be used to protect the wallet's software-side internal state, which
// must not be held exlusively during hardware communication. A communication
// lock can be used to achieve exclusive access to the device itself, this one
// however should allow "skipping" waiting for operations that might want to
// use the device, but can live without too (e.g. account self-derivation).
//
// Since we have two locks, it's important to know how to properly use them:
// - Communication requires the `device` to not change, so obtaining the
// commsLock should be done after having a stateLock.
// - Communication must not disable read access to the wallet state, so it
// must only ever hold a *read* lock to stateLock.
commsLock chan struct{} // Mutex (buf=1) for the USB comms without keeping the state locked
stateLock sync.RWMutex // Protects read and write access to the wallet struct fields
log log.Logger // Contextual logger to tag the base with its id
}
// URL implements accounts.Wallet, returning the URL of the USB hardware device.
func (w *wallet) URL() accounts.URL {
return *w.url // Immutable, no need for a lock
}
// Status implements accounts.Wallet, returning a custom status message from the
// underlying vendor-specific hardware wallet implementation.
func (w *wallet) Status() (string, error) {
w.stateLock.RLock() // No device communication, state lock is enough
defer w.stateLock.RUnlock()
status, failure := w.driver.Status()
if w.device == nil {
return "Closed", failure
}
return status, failure
}
// Open implements accounts.Wallet, attempting to open a USB connection to the
// hardware wallet.
func (w *wallet) Open(passphrase string) error {
w.stateLock.Lock() // State lock is enough since there's no connection yet at this point
defer w.stateLock.Unlock()
// If the device was already opened once, refuse to try again
if w.paths != nil {
return accounts.ErrWalletAlreadyOpen
}
// Make sure the actual device connection is done only once
if w.device == nil {
device, err := w.info.Open()
if err != nil {
return err
}
w.device = device
w.commsLock = make(chan struct{}, 1)
w.commsLock <- struct{}{} // Enable lock
}
// Delegate device initialization to the underlying driver
if err := w.driver.Open(w.device, passphrase); err != nil {
return err
}
// Connection successful, start life-cycle management
w.paths = make(map[common.Address]accounts.DerivationPath)
w.deriveReq = make(chan chan struct{})
w.deriveQuit = make(chan chan error)
w.healthQuit = make(chan chan error)
go w.heartbeat()
go w.selfDerive()
// Notify anyone listening for wallet events that a new device is accessible
go w.hub.updateFeed.Send(accounts.WalletEvent{Wallet: w, Kind: accounts.WalletOpened})
return nil
}
// heartbeat is a health check loop for the USB wallets to periodically verify
// whether they are still present or if they malfunctioned.
func (w *wallet) heartbeat() {
w.log.Debug("USB wallet health-check started")
defer w.log.Debug("USB wallet health-check stopped")
// Execute heartbeat checks until termination or error
var (
errc chan error
err error
)
for errc == nil && err == nil {
// Wait until termination is requested or the heartbeat cycle arrives
select {
case errc = <-w.healthQuit:
// Termination requested
continue
case <-time.After(heartbeatCycle):
// Heartbeat time
}
// Execute a tiny data exchange to see responsiveness
w.stateLock.RLock()
if w.device == nil {
// Terminated while waiting for the lock
w.stateLock.RUnlock()
continue
}
<-w.commsLock // Don't lock state while resolving version
err = w.driver.Heartbeat()
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
if err != nil {
w.stateLock.Lock() // Lock state to tear the wallet down
w.close()
w.stateLock.Unlock()
}
// Ignore non hardware related errors
err = nil
}
// In case of error, wait for termination
if err != nil {
w.log.Debug("USB wallet health-check failed", "err", err)
errc = <-w.healthQuit
}
errc <- err
}
// Close implements accounts.Wallet, closing the USB connection to the device.
func (w *wallet) Close() error {
// Ensure the wallet was opened
w.stateLock.RLock()
hQuit, dQuit := w.healthQuit, w.deriveQuit
w.stateLock.RUnlock()
// Terminate the health checks
var herr error
if hQuit != nil {
errc := make(chan error)
hQuit <- errc
herr = <-errc // Save for later, we *must* close the USB
}
// Terminate the self-derivations
var derr error
if dQuit != nil {
errc := make(chan error)
dQuit <- errc
derr = <-errc // Save for later, we *must* close the USB
}
// Terminate the device connection
w.stateLock.Lock()
defer w.stateLock.Unlock()
w.healthQuit = nil
w.deriveQuit = nil
w.deriveReq = nil
if err := w.close(); err != nil {
return err
}
if herr != nil {
return herr
}
return derr
}
// close is the internal wallet closer that terminates the USB connection and
// resets all the fields to their defaults.
//
// Note, close assumes the state lock is held!
func (w *wallet) close() error {
// Allow duplicate closes, especially for health-check failures
if w.device == nil {
return nil
}
// Close the device, clear everything, then return
w.device.Close()
w.device = nil
w.accounts, w.paths = nil, nil
w.driver.Close()
return nil
}
// Accounts implements accounts.Wallet, returning the list of accounts pinned to
// the USB hardware wallet. If self-derivation was enabled, the account list is
// periodically expanded based on current chain state.
func (w *wallet) Accounts() []accounts.Account {
// Attempt self-derivation if it's running
reqc := make(chan struct{}, 1)
select {
case w.deriveReq <- reqc:
// Self-derivation request accepted, wait for it
<-reqc
default:
// Self-derivation offline, throttled or busy, skip
}
// Return whatever account list we ended up with
w.stateLock.RLock()
defer w.stateLock.RUnlock()
cpy := make([]accounts.Account, len(w.accounts))
copy(cpy, w.accounts)
return cpy
}
// selfDerive is an account derivation loop that upon request attempts to find
// new non-zero accounts.
func (w *wallet) selfDerive() {
w.log.Debug("USB wallet self-derivation started")
defer w.log.Debug("USB wallet self-derivation stopped")
// Execute self-derivations until termination or error
var (
reqc chan struct{}
errc chan error
err error
)
for errc == nil && err == nil {
// Wait until either derivation or termination is requested
select {
case errc = <-w.deriveQuit:
// Termination requested
continue
case reqc = <-w.deriveReq:
// Account discovery requested
}
// Derivation needs a chain and device access, skip if either unavailable
w.stateLock.RLock()
if w.device == nil || w.deriveChain == nil {
w.stateLock.RUnlock()
reqc <- struct{}{}
continue
}
select {
case <-w.commsLock:
default:
w.stateLock.RUnlock()
reqc <- struct{}{}
continue
}
// Device lock obtained, derive the next batch of accounts
var (
accs []accounts.Account
paths []accounts.DerivationPath
nextAddr = w.deriveNextAddr
nextPath = w.deriveNextPath
context = context.Background()
)
for empty := false; !empty; {
// Retrieve the next derived Ethereum account
if nextAddr == (common.Address{}) {
if nextAddr, err = w.driver.Derive(nextPath); err != nil {
w.log.Warn("USB wallet account derivation failed", "err", err)
break
}
}
// Check the account's status against the current chain state
var (
balance *big.Int
nonce uint64
)
balance, err = w.deriveChain.BalanceAt(context, nextAddr, nil)
if err != nil {
w.log.Warn("USB wallet balance retrieval failed", "err", err)
break
}
nonce, err = w.deriveChain.NonceAt(context, nextAddr, nil)
if err != nil {
w.log.Warn("USB wallet nonce retrieval failed", "err", err)
break
}
// If the next account is empty, stop self-derivation, but add it nonetheless
if balance.Sign() == 0 && nonce == 0 {
empty = true
}
// We've just self-derived a new account, start tracking it locally
path := make(accounts.DerivationPath, len(nextPath))
copy(path[:], nextPath[:])
paths = append(paths, path)
account := accounts.Account{
Address: nextAddr,
URL: accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)},
}
accs = append(accs, account)
// Display a log message to the user for new (or previously empty accounts)
if _, known := w.paths[nextAddr]; !known || (!empty && nextAddr == w.deriveNextAddr) {
w.log.Info("USB wallet discovered new account", "address", nextAddr, "path", path, "balance", balance, "nonce", nonce)
}
// Fetch the next potential account
if !empty {
nextAddr = common.Address{}
nextPath[len(nextPath)-1]++
}
}
// Self derivation complete, release device lock
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
// Insert any accounts successfully derived
w.stateLock.Lock()
for i := 0; i < len(accs); i++ {
if _, ok := w.paths[accs[i].Address]; !ok {
w.accounts = append(w.accounts, accs[i])
w.paths[accs[i].Address] = paths[i]
}
}
// Shift the self-derivation forward
// TODO(karalabe): don't overwrite changes from wallet.SelfDerive
w.deriveNextAddr = nextAddr
w.deriveNextPath = nextPath
w.stateLock.Unlock()
// Notify the user of termination and loop after a bit of time (to avoid trashing)
reqc <- struct{}{}
if err == nil {
select {
case errc = <-w.deriveQuit:
// Termination requested, abort
case <-time.After(selfDeriveThrottling):
// Waited enough, willing to self-derive again
}
}
}
// In case of error, wait for termination
if err != nil {
w.log.Debug("USB wallet self-derivation failed", "err", err)
errc = <-w.deriveQuit
}
errc <- err
}
// Contains implements accounts.Wallet, returning whether a particular account is
// or is not pinned into this wallet instance. Although we could attempt to resolve
// unpinned accounts, that would be an non-negligible hardware operation.
func (w *wallet) Contains(account accounts.Account) bool {
w.stateLock.RLock()
defer w.stateLock.RUnlock()
_, exists := w.paths[account.Address]
return exists
}
// Derive implements accounts.Wallet, deriving a new account at the specific
// derivation path. If pin is set to true, the account will be added to the list
// of tracked accounts.
func (w *wallet) Derive(path accounts.DerivationPath, pin bool) (accounts.Account, error) {
// Try to derive the actual account and update its URL if successful
w.stateLock.RLock() // Avoid device disappearing during derivation
if w.device == nil {
w.stateLock.RUnlock()
return accounts.Account{}, accounts.ErrWalletClosed
}
<-w.commsLock // Avoid concurrent hardware access
address, err := w.driver.Derive(path)
w.commsLock <- struct{}{}
w.stateLock.RUnlock()
// If an error occurred or no pinning was requested, return
if err != nil {
return accounts.Account{}, err
}
account := accounts.Account{
Address: address,
URL: accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)},
}
if !pin {
return account, nil
}
// Pinning needs to modify the state
w.stateLock.Lock()
defer w.stateLock.Unlock()
if _, ok := w.paths[address]; !ok {
w.accounts = append(w.accounts, account)
w.paths[address] = path
}
return account, nil
}
// SelfDerive implements accounts.Wallet, trying to discover accounts that the
// user used previously (based on the chain state), but ones that he/she did not
// explicitly pin to the wallet manually. To avoid chain head monitoring, self
// derivation only runs during account listing (and even then throttled).
func (w *wallet) SelfDerive(base accounts.DerivationPath, chain ethereum.ChainStateReader) {
w.stateLock.Lock()
defer w.stateLock.Unlock()
w.deriveNextPath = make(accounts.DerivationPath, len(base))
copy(w.deriveNextPath[:], base[:])
w.deriveNextAddr = common.Address{}
w.deriveChain = chain
}
// SignHash implements accounts.Wallet, however signing arbitrary data is not
// supported for hardware wallets, so this method will always return an error.
func (w *wallet) SignHash(account accounts.Account, hash []byte) ([]byte, error) {
return nil, accounts.ErrNotSupported
}
// SignTx implements accounts.Wallet. It sends the transaction over to the Ledger
// wallet to request a confirmation from the user. It returns either the signed
// transaction or a failure if the user denied the transaction.
//
// Note, if the version of the Ethereum application running on the Ledger wallet is
// too old to sign EIP-155 transactions, but such is requested nonetheless, an error
// will be returned opposed to silently signing in Homestead mode.
func (w *wallet) SignTx(account accounts.Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
w.stateLock.RLock() // Comms have own mutex, this is for the state fields
defer w.stateLock.RUnlock()
// If the wallet is closed, abort
if w.device == nil {
return nil, accounts.ErrWalletClosed
}
// Make sure the requested account is contained within
path, ok := w.paths[account.Address]
if !ok {
return nil, accounts.ErrUnknownAccount
}
// All infos gathered and metadata checks out, request signing
<-w.commsLock
defer func() { w.commsLock <- struct{}{} }()
// Ensure the device isn't screwed with while user confirmation is pending
// TODO(karalabe): remove if hotplug lands on Windows
w.hub.commsLock.Lock()
w.hub.commsPend++
w.hub.commsLock.Unlock()
defer func() {
w.hub.commsLock.Lock()
w.hub.commsPend--
w.hub.commsLock.Unlock()
}()
// Sign the transaction and verify the sender to avoid hardware fault surprises
sender, signed, err := w.driver.SignTx(path, tx, chainID)
if err != nil {
return nil, err
}
if sender != account.Address {
return nil, fmt.Errorf("signer mismatch: expected %s, got %s", account.Address.Hex(), sender.Hex())
}
return signed, nil
}
// SignHashWithPassphrase implements accounts.Wallet, however signing arbitrary
// data is not supported for Ledger wallets, so this method will always return
// an error.
func (w *wallet) SignHashWithPassphrase(account accounts.Account, passphrase string, hash []byte) ([]byte, error) {
return w.SignHash(account, hash)
}
// SignTxWithPassphrase implements accounts.Wallet, attempting to sign the given
// transaction with the given account using passphrase as extra authentication.
// Since USB wallets don't rely on passphrases, these are silently ignored.
func (w *wallet) SignTxWithPassphrase(account accounts.Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
return w.SignTx(account, tx, chainID)
}

View File

@ -251,7 +251,9 @@ func startNode(ctx *cli.Context, stack *node.Node) {
log.Warn("New wallet appeared, failed to open", "url", event.Wallet.URL(), "err", err) log.Warn("New wallet appeared, failed to open", "url", event.Wallet.URL(), "err", err)
} }
case accounts.WalletOpened: case accounts.WalletOpened:
log.Info("New wallet appeared", "url", event.Wallet.URL(), "status", event.Wallet.Status()) status, _ := event.Wallet.Status()
log.Info("New wallet appeared", "url", event.Wallet.URL(), "status", status)
if event.Wallet.URL().Scheme == "ledger" { if event.Wallet.URL().Scheme == "ledger" {
event.Wallet.SelfDerive(accounts.DefaultLedgerBaseDerivationPath, stateReader) event.Wallet.SelfDerive(accounts.DefaultLedgerBaseDerivationPath, stateReader)
} else { } else {

View File

@ -230,18 +230,25 @@ func (s *PrivateAccountAPI) ListAccounts() []common.Address {
type rawWallet struct { type rawWallet struct {
URL string `json:"url"` URL string `json:"url"`
Status string `json:"status"` Status string `json:"status"`
Accounts []accounts.Account `json:"accounts"` Failure string `json:"failure,omitempty"`
Accounts []accounts.Account `json:"accounts,omitempty"`
} }
// ListWallets will return a list of wallets this node manages. // ListWallets will return a list of wallets this node manages.
func (s *PrivateAccountAPI) ListWallets() []rawWallet { func (s *PrivateAccountAPI) ListWallets() []rawWallet {
wallets := make([]rawWallet, 0) // return [] instead of nil if empty wallets := make([]rawWallet, 0) // return [] instead of nil if empty
for _, wallet := range s.am.Wallets() { for _, wallet := range s.am.Wallets() {
wallets = append(wallets, rawWallet{ status, failure := wallet.Status()
raw := rawWallet{
URL: wallet.URL().String(), URL: wallet.URL().String(),
Status: wallet.Status(), Status: status,
Accounts: wallet.Accounts(), Accounts: wallet.Accounts(),
}) }
if failure != nil {
raw.Failure = failure.Error()
}
wallets = append(wallets, raw)
} }
return wallets return wallets
} }