diff options
Diffstat (limited to 'accounts/usbwallet/ledger_wallet.go')
| -rw-r--r-- | accounts/usbwallet/ledger_wallet.go | 154 |
1 files changed, 118 insertions, 36 deletions
diff --git a/accounts/usbwallet/ledger_wallet.go b/accounts/usbwallet/ledger_wallet.go index f712a503f..0481a8990 100644 --- a/accounts/usbwallet/ledger_wallet.go +++ b/accounts/usbwallet/ledger_wallet.go @@ -29,11 +29,10 @@ import ( "fmt" "io" "math/big" - "strconv" - "strings" "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" @@ -41,10 +40,15 @@ import ( "github.com/ethereum/go-ethereum/logger/glog" "github.com/ethereum/go-ethereum/rlp" "github.com/karalabe/gousb/usb" + "golang.org/x/net/context" ) -// ledgerDerivationPath is the base derivation parameters used by the wallet. -var ledgerDerivationPath = []uint32{0x80000000 + 44, 0x80000000 + 60, 0x80000000 + 0, 0} +// Maximum time between wallet health checks to detect USB unplugs. +const ledgerHeartbeatCycle = time.Second + +// Minimum time to wait between self derivation attempts, even it the user is +// requesting accounts like crazy. +const ledgerSelfDeriveThrottling = time.Second // ledgerOpcode is an enumeration encoding the supported Ledger opcodes. type ledgerOpcode byte @@ -82,9 +86,15 @@ type ledgerWallet struct { output usb.Endpoint // Output endpoint to receive data from this device 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) - accounts []accounts.Account // List of derive accounts pinned on the Ledger - paths map[common.Address][]uint32 // Known derivation paths for signing operations + version [3]byte // Current version of the Ledger Ethereum app (zero if app is offline) + accounts []accounts.Account // List of derive accounts pinned on the Ledger + paths map[common.Address]accounts.DerivationPath // Known derivation paths for signing operations + + selfDeriveNextPath accounts.DerivationPath // Next derivation path for account auto-discovery + selfDeriveNextAddr common.Address // Next derived account address for auto-discovery + selfDerivePrevZero common.Address // Last zero-address where auto-discovery stopped + selfDeriveChain ethereum.ChainStateReader // Blockchain state reader to discover used account with + selfDeriveTime time.Time // Timestamp of the last self-derivation to avoid thrashing quit chan chan error lock sync.RWMutex @@ -107,12 +117,17 @@ func (w *ledgerWallet) Status() string { if w.device == nil { return "Closed" } - if w.version == [3]byte{0, 0, 0} { + 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. +func (w *ledgerWallet) offline() bool { + return w.version == [3]byte{0, 0, 0} +} + // 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 // is silently discarded. @@ -176,13 +191,13 @@ func (w *ledgerWallet) Open(passphrase string) error { // Wallet seems to be successfully opened, guess if the Ethereum app is running w.device, w.input, w.output = device, input, output - w.paths = make(map[common.Address][]uint32) + w.paths = make(map[common.Address]accounts.DerivationPath) w.quit = make(chan chan error) defer func() { go w.heartbeat() }() - if _, err := w.deriveAddress(ledgerDerivationPath); err != nil { + if _, err := w.deriveAddress(accounts.DefaultBaseDerivationPath); err != nil { // Ethereum app is not running, nothing more to do, return return nil } @@ -209,7 +224,7 @@ func (w *ledgerWallet) heartbeat() { case errc = <-w.quit: // Termination requested continue - case <-time.After(time.Second): + case <-time.After(ledgerHeartbeatCycle): // Heartbeat time } // Execute a tiny data exchange to see responsiveness @@ -242,16 +257,86 @@ func (w *ledgerWallet) Close() error { return err } w.device, w.input, w.output, w.paths, w.quit = nil, nil, nil, nil, nil + w.version = [3]byte{} return herr // If all went well, return any health-check errors } // Accounts implements accounts.Wallet, returning the list of accounts pinned to -// the Ledger hardware wallet. +// 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 { - w.lock.RLock() - defer w.lock.RUnlock() + w.lock.Lock() + defer w.lock.Unlock() + + // If the wallet is offline, there are no accounts to return + if w.offline() { + return nil + } + // If no self derivation is done (or throttled), return the current accounts + if w.selfDeriveChain == nil || time.Since(w.selfDeriveTime) < ledgerSelfDeriveThrottling { + cpy := make([]accounts.Account, len(w.accounts)) + copy(cpy, w.accounts) + return cpy + } + // Self derivation requested, try to expand our account list + ctx := context.Background() + for empty := false; !empty; { + // Retrieve the next derived Ethereum account + var err error + if w.selfDeriveNextAddr == (common.Address{}) { + w.selfDeriveNextAddr, err = w.deriveAddress(w.selfDeriveNextPath) + if err != nil { + // Derivation failed, disable auto discovery + glog.V(logger.Warn).Infof("self-derivation failed: %v", err) + w.selfDeriveChain = nil + break + } + } + // Check the account's status against the current chain state + balance, err := w.selfDeriveChain.BalanceAt(ctx, w.selfDeriveNextAddr, nil) + if err != nil { + glog.V(logger.Warn).Infof("self-derivation balance retrieval failed: %v", err) + w.selfDeriveChain = nil + break + } + nonce, err := w.selfDeriveChain.NonceAt(ctx, w.selfDeriveNextAddr, nil) + if err != nil { + glog.V(logger.Warn).Infof("self-derivation nonce retrieval failed: %v", err) + w.selfDeriveChain = nil + break + } + // If the next account is empty, stop self-derivation, but add it nonetheless + if balance.BitLen() == 0 && nonce == 0 { + w.selfDerivePrevZero = w.selfDeriveNextAddr + empty = true + } + // We've just self-derived a new non-zero account, start tracking it + path := make(accounts.DerivationPath, len(w.selfDeriveNextPath)) + copy(path[:], w.selfDeriveNextPath[:]) + account := accounts.Account{ + Address: w.selfDeriveNextAddr, + URL: accounts.URL{Scheme: w.url.Scheme, Path: fmt.Sprintf("%s/%s", w.url.Path, path)}, + } + _, known := w.paths[w.selfDeriveNextAddr] + if !known || (!empty && w.selfDeriveNextAddr == w.selfDerivePrevZero) { + // Either fully new account, or previous zero. Report discovery either way + glog.V(logger.Info).Infof("%s discovered %s (balance %d, nonce %d) at %s", w.url.String(), w.selfDeriveNextAddr.Hex(), balance, nonce, path) + } + if !known { + w.accounts = append(w.accounts, account) + w.paths[w.selfDeriveNextAddr] = path + } + // Fetch the next potential account + if !empty { + w.selfDeriveNextAddr = common.Address{} + w.selfDeriveNextPath[len(w.selfDeriveNextPath)-1]++ + } + } + w.selfDeriveTime = time.Now() + + // Return whatever account list we ended up with cpy := make([]accounts.Account, len(w.accounts)) copy(cpy, w.accounts) return cpy @@ -271,34 +356,16 @@ func (w *ledgerWallet) Contains(account accounts.Account) bool { // 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 string, pin bool) (accounts.Account, error) { +func (w *ledgerWallet) Derive(path accounts.DerivationPath, pin bool) (accounts.Account, error) { w.lock.Lock() defer w.lock.Unlock() // If the wallet is closed, or the Ethereum app doesn't run, abort - if w.device == nil || w.version == [3]byte{0, 0, 0} { + if w.device == nil || w.offline() { return accounts.Account{}, accounts.ErrWalletClosed } - // All seems fine, convert the user derivation path to Ledger representation - path = strings.TrimPrefix(path, "/") - - parts := strings.Split(path, "/") - lpath := make([]uint32, len(parts)) - for i, part := range parts { - // Handle hardened paths - if strings.HasSuffix(part, "'") { - lpath[i] = 0x80000000 - part = strings.TrimSuffix(part, "'") - } - // Handle the non hardened component - val, err := strconv.Atoi(part) - if err != nil { - return accounts.Account{}, fmt.Errorf("path element %d: %v", i, err) - } - lpath[i] += uint32(val) - } // Try to derive the actual account and update it's URL if succeeful - address, err := w.deriveAddress(lpath) + address, err := w.deriveAddress(path) if err != nil { return accounts.Account{}, err } @@ -310,12 +377,27 @@ func (w *ledgerWallet) Derive(path string, pin bool) (accounts.Account, error) { if pin { if _, ok := w.paths[address]; !ok { w.accounts = append(w.accounts, account) - w.paths[address] = lpath + 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.lock.Lock() + defer w.lock.Unlock() + + w.selfDeriveNextPath = make(accounts.DerivationPath, len(base)) + copy(w.selfDeriveNextPath[:], base[:]) + + w.selfDeriveNextAddr = common.Address{} + w.selfDeriveChain = 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) { |