b628d72766
This changes the CI / release builds to use the latest Go version. It also upgrades golangci-lint to a newer version compatible with Go 1.19. In Go 1.19, godoc has gained official support for links and lists. The syntax for code blocks in doc comments has changed and now requires a leading tab character. gofmt adapts comments to the new syntax automatically, so there are a lot of comment re-formatting changes in this PR. We need to apply the new format in order to pass the CI lint stage with Go 1.19. With the linter upgrade, I have decided to disable 'gosec' - it produces too many false-positive warnings. The 'deadcode' and 'varcheck' linters have also been removed because golangci-lint warns about them being unmaintained. 'unused' provides similar coverage and we already have it enabled, so we don't lose much with this change.
547 lines
20 KiB
Go
547 lines
20 KiB
Go
// Copyright 2017 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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// This file contains the implementation for interacting with the Ledger hardware
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// wallets. The wire protocol spec can be found in the Ledger Blue GitHub repo:
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// https://raw.githubusercontent.com/LedgerHQ/blue-app-eth/master/doc/ethapp.asc
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package usbwallet
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import (
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"encoding/binary"
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"encoding/hex"
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"errors"
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"fmt"
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"io"
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"math/big"
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"github.com/ethereum/go-ethereum/accounts"
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"github.com/ethereum/go-ethereum/common"
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"github.com/ethereum/go-ethereum/common/hexutil"
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"github.com/ethereum/go-ethereum/core/types"
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"github.com/ethereum/go-ethereum/crypto"
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"github.com/ethereum/go-ethereum/log"
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"github.com/ethereum/go-ethereum/rlp"
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)
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// ledgerOpcode is an enumeration encoding the supported Ledger opcodes.
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type ledgerOpcode byte
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// ledgerParam1 is an enumeration encoding the supported Ledger parameters for
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// specific opcodes. The same parameter values may be reused between opcodes.
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type ledgerParam1 byte
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// ledgerParam2 is an enumeration encoding the supported Ledger parameters for
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// specific opcodes. The same parameter values may be reused between opcodes.
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type ledgerParam2 byte
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const (
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ledgerOpRetrieveAddress ledgerOpcode = 0x02 // Returns the public key and Ethereum address for a given BIP 32 path
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ledgerOpSignTransaction ledgerOpcode = 0x04 // Signs an Ethereum transaction after having the user validate the parameters
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ledgerOpGetConfiguration ledgerOpcode = 0x06 // Returns specific wallet application configuration
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ledgerOpSignTypedMessage ledgerOpcode = 0x0c // Signs an Ethereum message following the EIP 712 specification
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ledgerP1DirectlyFetchAddress ledgerParam1 = 0x00 // Return address directly from the wallet
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ledgerP1InitTypedMessageData ledgerParam1 = 0x00 // First chunk of Typed Message data
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ledgerP1InitTransactionData ledgerParam1 = 0x00 // First transaction data block for signing
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ledgerP1ContTransactionData ledgerParam1 = 0x80 // Subsequent transaction data block for signing
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ledgerP2DiscardAddressChainCode ledgerParam2 = 0x00 // Do not return the chain code along with the address
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)
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// errLedgerReplyInvalidHeader is the error message returned by a Ledger data exchange
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// if the device replies with a mismatching header. This usually means the device
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// is in browser mode.
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var errLedgerReplyInvalidHeader = errors.New("ledger: invalid reply header")
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// errLedgerInvalidVersionReply is the error message returned by a Ledger version retrieval
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// when a response does arrive, but it does not contain the expected data.
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var errLedgerInvalidVersionReply = errors.New("ledger: invalid version reply")
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// ledgerDriver implements the communication with a Ledger hardware wallet.
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type ledgerDriver struct {
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device io.ReadWriter // USB device connection to communicate through
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version [3]byte // Current version of the Ledger firmware (zero if app is offline)
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browser bool // Flag whether the Ledger is in browser mode (reply channel mismatch)
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failure error // Any failure that would make the device unusable
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log log.Logger // Contextual logger to tag the ledger with its id
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}
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// newLedgerDriver creates a new instance of a Ledger USB protocol driver.
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func newLedgerDriver(logger log.Logger) driver {
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return &ledgerDriver{
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log: logger,
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}
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}
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// Status implements usbwallet.driver, returning various states the Ledger can
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// currently be in.
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func (w *ledgerDriver) Status() (string, error) {
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if w.failure != nil {
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return fmt.Sprintf("Failed: %v", w.failure), w.failure
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}
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if w.browser {
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return "Ethereum app in browser mode", w.failure
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}
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if w.offline() {
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return "Ethereum app offline", w.failure
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}
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return fmt.Sprintf("Ethereum app v%d.%d.%d online", w.version[0], w.version[1], w.version[2]), w.failure
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}
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// offline returns whether the wallet and the Ethereum app is offline or not.
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//
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// The method assumes that the state lock is held!
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func (w *ledgerDriver) offline() bool {
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return w.version == [3]byte{0, 0, 0}
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}
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// Open implements usbwallet.driver, attempting to initialize the connection to the
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// Ledger hardware wallet. The Ledger does not require a user passphrase, so that
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// parameter is silently discarded.
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func (w *ledgerDriver) Open(device io.ReadWriter, passphrase string) error {
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w.device, w.failure = device, nil
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_, err := w.ledgerDerive(accounts.DefaultBaseDerivationPath)
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if err != nil {
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// Ethereum app is not running or in browser mode, nothing more to do, return
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if err == errLedgerReplyInvalidHeader {
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w.browser = true
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}
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return nil
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}
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// Try to resolve the Ethereum app's version, will fail prior to v1.0.2
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if w.version, err = w.ledgerVersion(); err != nil {
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w.version = [3]byte{1, 0, 0} // Assume worst case, can't verify if v1.0.0 or v1.0.1
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}
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return nil
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}
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// Close implements usbwallet.driver, cleaning up and metadata maintained within
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// the Ledger driver.
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func (w *ledgerDriver) Close() error {
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w.browser, w.version = false, [3]byte{}
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return nil
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}
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// Heartbeat implements usbwallet.driver, performing a sanity check against the
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// Ledger to see if it's still online.
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func (w *ledgerDriver) Heartbeat() error {
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if _, err := w.ledgerVersion(); err != nil && err != errLedgerInvalidVersionReply {
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w.failure = err
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return err
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}
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return nil
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}
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// Derive implements usbwallet.driver, sending a derivation request to the Ledger
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// and returning the Ethereum address located on that derivation path.
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func (w *ledgerDriver) Derive(path accounts.DerivationPath) (common.Address, error) {
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return w.ledgerDerive(path)
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}
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// SignTx implements usbwallet.driver, sending the transaction to the Ledger and
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// waiting for the user to confirm or deny the transaction.
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//
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// Note, if the version of the Ethereum application running on the Ledger wallet is
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// too old to sign EIP-155 transactions, but such is requested nonetheless, an error
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// will be returned opposed to silently signing in Homestead mode.
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func (w *ledgerDriver) SignTx(path accounts.DerivationPath, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
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// If the Ethereum app doesn't run, abort
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if w.offline() {
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return common.Address{}, nil, accounts.ErrWalletClosed
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}
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// Ensure the wallet is capable of signing the given transaction
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if chainID != nil && w.version[0] <= 1 && w.version[1] <= 0 && w.version[2] <= 2 {
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//lint:ignore ST1005 brand name displayed on the console
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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])
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}
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// All infos gathered and metadata checks out, request signing
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return w.ledgerSign(path, tx, chainID)
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}
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// SignTypedMessage implements usbwallet.driver, sending the message to the Ledger and
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// waiting for the user to sign or deny the transaction.
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//
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// Note: this was introduced in the ledger 1.5.0 firmware
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func (w *ledgerDriver) SignTypedMessage(path accounts.DerivationPath, domainHash []byte, messageHash []byte) ([]byte, error) {
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// If the Ethereum app doesn't run, abort
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if w.offline() {
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return nil, accounts.ErrWalletClosed
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}
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// Ensure the wallet is capable of signing the given transaction
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if w.version[0] < 1 && w.version[1] < 5 {
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//lint:ignore ST1005 brand name displayed on the console
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return nil, fmt.Errorf("Ledger version >= 1.5.0 required for EIP-712 signing (found version v%d.%d.%d)", w.version[0], w.version[1], w.version[2])
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}
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// All infos gathered and metadata checks out, request signing
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return w.ledgerSignTypedMessage(path, domainHash, messageHash)
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}
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// ledgerVersion retrieves the current version of the Ethereum wallet app running
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// on the Ledger wallet.
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//
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// The version retrieval protocol is defined as follows:
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//
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// CLA | INS | P1 | P2 | Lc | Le
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// ----+-----+----+----+----+---
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// E0 | 06 | 00 | 00 | 00 | 04
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//
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// With no input data, and the output data being:
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//
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// Description | Length
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// ---------------------------------------------------+--------
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// Flags 01: arbitrary data signature enabled by user | 1 byte
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// Application major version | 1 byte
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// Application minor version | 1 byte
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// Application patch version | 1 byte
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func (w *ledgerDriver) ledgerVersion() ([3]byte, error) {
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// Send the request and wait for the response
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reply, err := w.ledgerExchange(ledgerOpGetConfiguration, 0, 0, nil)
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if err != nil {
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return [3]byte{}, err
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}
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if len(reply) != 4 {
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return [3]byte{}, errLedgerInvalidVersionReply
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}
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// Cache the version for future reference
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var version [3]byte
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copy(version[:], reply[1:])
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return version, nil
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}
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// ledgerDerive retrieves the currently active Ethereum address from a Ledger
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// wallet at the specified derivation path.
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//
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// The address derivation protocol is defined as follows:
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//
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// CLA | INS | P1 | P2 | Lc | Le
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// ----+-----+----+----+-----+---
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// E0 | 02 | 00 return address
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// 01 display address and confirm before returning
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// | 00: do not return the chain code
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// | 01: return the chain code
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// | var | 00
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//
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// Where the input data is:
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//
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// Description | Length
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// -------------------------------------------------+--------
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// Number of BIP 32 derivations to perform (max 10) | 1 byte
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// First derivation index (big endian) | 4 bytes
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// ... | 4 bytes
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// Last derivation index (big endian) | 4 bytes
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//
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// And the output data is:
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//
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// Description | Length
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// ------------------------+-------------------
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// Public Key length | 1 byte
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// Uncompressed Public Key | arbitrary
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// Ethereum address length | 1 byte
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// Ethereum address | 40 bytes hex ascii
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// Chain code if requested | 32 bytes
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func (w *ledgerDriver) ledgerDerive(derivationPath []uint32) (common.Address, error) {
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// Flatten the derivation path into the Ledger request
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path := make([]byte, 1+4*len(derivationPath))
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path[0] = byte(len(derivationPath))
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for i, component := range derivationPath {
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binary.BigEndian.PutUint32(path[1+4*i:], component)
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}
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// Send the request and wait for the response
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reply, err := w.ledgerExchange(ledgerOpRetrieveAddress, ledgerP1DirectlyFetchAddress, ledgerP2DiscardAddressChainCode, path)
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if err != nil {
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return common.Address{}, err
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}
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// Discard the public key, we don't need that for now
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if len(reply) < 1 || len(reply) < 1+int(reply[0]) {
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return common.Address{}, errors.New("reply lacks public key entry")
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}
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reply = reply[1+int(reply[0]):]
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// Extract the Ethereum hex address string
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if len(reply) < 1 || len(reply) < 1+int(reply[0]) {
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return common.Address{}, errors.New("reply lacks address entry")
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}
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hexstr := reply[1 : 1+int(reply[0])]
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// Decode the hex sting into an Ethereum address and return
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var address common.Address
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if _, err = hex.Decode(address[:], hexstr); err != nil {
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return common.Address{}, err
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}
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return address, nil
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}
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// ledgerSign sends the transaction to the Ledger wallet, and waits for the user
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// to confirm or deny the transaction.
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//
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// The transaction signing protocol is defined as follows:
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//
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// CLA | INS | P1 | P2 | Lc | Le
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// ----+-----+----+----+-----+---
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// E0 | 04 | 00: first transaction data block
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// 80: subsequent transaction data block
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// | 00 | variable | variable
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//
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// Where the input for the first transaction block (first 255 bytes) is:
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//
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// Description | Length
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// -------------------------------------------------+----------
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// Number of BIP 32 derivations to perform (max 10) | 1 byte
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// First derivation index (big endian) | 4 bytes
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// ... | 4 bytes
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// Last derivation index (big endian) | 4 bytes
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// RLP transaction chunk | arbitrary
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//
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// And the input for subsequent transaction blocks (first 255 bytes) are:
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//
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// Description | Length
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// ----------------------+----------
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// RLP transaction chunk | arbitrary
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//
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// And the output data is:
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//
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// Description | Length
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// ------------+---------
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// signature V | 1 byte
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// signature R | 32 bytes
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// signature S | 32 bytes
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func (w *ledgerDriver) ledgerSign(derivationPath []uint32, tx *types.Transaction, chainID *big.Int) (common.Address, *types.Transaction, error) {
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// Flatten the derivation path into the Ledger request
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path := make([]byte, 1+4*len(derivationPath))
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path[0] = byte(len(derivationPath))
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for i, component := range derivationPath {
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binary.BigEndian.PutUint32(path[1+4*i:], component)
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}
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// Create the transaction RLP based on whether legacy or EIP155 signing was requested
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var (
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txrlp []byte
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err error
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)
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if chainID == nil {
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if txrlp, err = rlp.EncodeToBytes([]interface{}{tx.Nonce(), tx.GasPrice(), tx.Gas(), tx.To(), tx.Value(), tx.Data()}); err != nil {
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return common.Address{}, nil, err
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}
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} else {
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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 {
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return common.Address{}, nil, err
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}
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}
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payload := append(path, txrlp...)
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// Send the request and wait for the response
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var (
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op = ledgerP1InitTransactionData
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reply []byte
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)
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for len(payload) > 0 {
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// Calculate the size of the next data chunk
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chunk := 255
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if chunk > len(payload) {
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chunk = len(payload)
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}
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// Send the chunk over, ensuring it's processed correctly
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reply, err = w.ledgerExchange(ledgerOpSignTransaction, op, 0, payload[:chunk])
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if err != nil {
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return common.Address{}, nil, err
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}
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// Shift the payload and ensure subsequent chunks are marked as such
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payload = payload[chunk:]
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op = ledgerP1ContTransactionData
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}
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// Extract the Ethereum signature and do a sanity validation
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if len(reply) != crypto.SignatureLength {
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return common.Address{}, nil, errors.New("reply lacks signature")
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}
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signature := append(reply[1:], reply[0])
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// Create the correct signer and signature transform based on the chain ID
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var signer types.Signer
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if chainID == nil {
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signer = new(types.HomesteadSigner)
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} else {
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signer = types.NewEIP155Signer(chainID)
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signature[64] -= byte(chainID.Uint64()*2 + 35)
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}
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signed, err := tx.WithSignature(signer, signature)
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if err != nil {
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return common.Address{}, nil, err
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}
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sender, err := types.Sender(signer, signed)
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if err != nil {
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return common.Address{}, nil, err
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}
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return sender, signed, nil
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}
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// ledgerSignTypedMessage sends the transaction to the Ledger wallet, and waits for the user
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// to confirm or deny the transaction.
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//
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// The signing protocol is defined as follows:
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//
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// CLA | INS | P1 | P2 | Lc | Le
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// ----+-----+----+-----------------------------+-----+---
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// E0 | 0C | 00 | implementation version : 00 | variable | variable
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//
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// Where the input is:
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//
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// Description | Length
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// -------------------------------------------------+----------
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// Number of BIP 32 derivations to perform (max 10) | 1 byte
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// First derivation index (big endian) | 4 bytes
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// ... | 4 bytes
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// Last derivation index (big endian) | 4 bytes
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// domain hash | 32 bytes
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// message hash | 32 bytes
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//
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// And the output data is:
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//
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// Description | Length
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// ------------+---------
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// signature V | 1 byte
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// signature R | 32 bytes
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// signature S | 32 bytes
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func (w *ledgerDriver) ledgerSignTypedMessage(derivationPath []uint32, domainHash []byte, messageHash []byte) ([]byte, error) {
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// Flatten the derivation path into the Ledger request
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path := make([]byte, 1+4*len(derivationPath))
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path[0] = byte(len(derivationPath))
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for i, component := range derivationPath {
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binary.BigEndian.PutUint32(path[1+4*i:], component)
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}
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// Create the 712 message
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payload := append(path, domainHash...)
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payload = append(payload, messageHash...)
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// Send the request and wait for the response
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var (
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op = ledgerP1InitTypedMessageData
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reply []byte
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err error
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)
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// Send the message over, ensuring it's processed correctly
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reply, err = w.ledgerExchange(ledgerOpSignTypedMessage, op, 0, payload)
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if err != nil {
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return nil, err
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}
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// Extract the Ethereum signature and do a sanity validation
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if len(reply) != crypto.SignatureLength {
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return nil, errors.New("reply lacks signature")
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}
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signature := append(reply[1:], reply[0])
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return signature, nil
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}
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// ledgerExchange performs a data exchange with the Ledger wallet, sending it a
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// message and retrieving the response.
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//
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// The common transport header is defined as follows:
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//
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// Description | Length
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// --------------------------------------+----------
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// Communication channel ID (big endian) | 2 bytes
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// Command tag | 1 byte
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// Packet sequence index (big endian) | 2 bytes
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// Payload | arbitrary
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//
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// The Communication channel ID allows commands multiplexing over the same
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// 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
|
|
}
|