aboutsummaryrefslogtreecommitdiffstats
path: root/packages/subproviders/src/subproviders/ledger.ts
blob: 6ad5de2e2d82e5ae58d7ee1cfe193a5567c83f4c (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
import { assert } from '@0xproject/assert';
import { addressUtils } from '@0xproject/utils';
import EthereumTx = require('ethereumjs-tx');
import ethUtil = require('ethereumjs-util');
import HDNode = require('hdkey');
import * as _ from 'lodash';
import { Lock } from 'semaphore-async-await';

import {
    DerivedHDKeyInfo,
    LedgerEthereumClient,
    LedgerEthereumClientFactoryAsync,
    LedgerSubproviderConfigs,
    LedgerSubproviderErrors,
    PartialTxParams,
    WalletSubproviderErrors,
} from '../types';
import { walletUtils } from '../utils/wallet_utils';

import { BaseWalletSubprovider } from './base_wallet_subprovider';

const DEFAULT_BASE_DERIVATION_PATH = `44'/60'/0'`;
const ASK_FOR_ON_DEVICE_CONFIRMATION = false;
const SHOULD_GET_CHAIN_CODE = true;
const DEFAULT_NUM_ADDRESSES_TO_FETCH = 10;
const DEFAULT_ADDRESS_SEARCH_LIMIT = 1000;

/**
 * Subprovider for interfacing with a user's [Ledger Nano S](https://www.ledgerwallet.com/products/ledger-nano-s).
 * This subprovider intercepts all account related RPC requests (e.g message/transaction signing, etc...) and
 * re-routes them to a Ledger device plugged into the users computer.
 */
export class LedgerSubprovider extends BaseWalletSubprovider {
    // tslint:disable-next-line:no-unused-variable
    private readonly _nonceLock = new Lock();
    private readonly _connectionLock = new Lock();
    private readonly _networkId: number;
    private _baseDerivationPath: string;
    private readonly _ledgerEthereumClientFactoryAsync: LedgerEthereumClientFactoryAsync;
    private _ledgerClientIfExists?: LedgerEthereumClient;
    private readonly _shouldAlwaysAskForConfirmation: boolean;
    private readonly _addressSearchLimit: number;
    /**
     * Instantiates a LedgerSubprovider. Defaults to derivationPath set to `44'/60'/0'`.
     * TestRPC/Ganache defaults to `m/44'/60'/0'/0`, so set this in the configs if desired.
     * @param config Several available configurations
     * @return LedgerSubprovider instance
     */
    constructor(config: LedgerSubproviderConfigs) {
        super();
        this._networkId = config.networkId;
        this._ledgerEthereumClientFactoryAsync = config.ledgerEthereumClientFactoryAsync;
        this._baseDerivationPath = config.baseDerivationPath || DEFAULT_BASE_DERIVATION_PATH;
        this._shouldAlwaysAskForConfirmation =
            !_.isUndefined(config.accountFetchingConfigs) &&
            !_.isUndefined(config.accountFetchingConfigs.shouldAskForOnDeviceConfirmation)
                ? config.accountFetchingConfigs.shouldAskForOnDeviceConfirmation
                : ASK_FOR_ON_DEVICE_CONFIRMATION;
        this._addressSearchLimit =
            !_.isUndefined(config.accountFetchingConfigs) &&
            !_.isUndefined(config.accountFetchingConfigs.addressSearchLimit)
                ? config.accountFetchingConfigs.addressSearchLimit
                : DEFAULT_ADDRESS_SEARCH_LIMIT;
    }
    /**
     * Retrieve the set derivation path
     * @returns derivation path
     */
    public getPath(): string {
        return this._baseDerivationPath;
    }
    /**
     * Set a desired derivation path when computing the available user addresses
     * @param basDerivationPath The desired derivation path (e.g `44'/60'/0'`)
     */
    public setPath(basDerivationPath: string): void {
        this._baseDerivationPath = basDerivationPath;
    }
    /**
     * Retrieve a users Ledger accounts. The accounts are derived from the derivationPath,
     * master public key and chain code. Because of this, you can request as many accounts
     * as you wish and it only requires a single request to the Ledger device. This method
     * is automatically called when issuing a `eth_accounts` JSON RPC request via your providerEngine
     * instance.
     * @param numberOfAccounts Number of accounts to retrieve (default: 10)
     * @return An array of accounts
     */
    public async getAccountsAsync(numberOfAccounts: number = DEFAULT_NUM_ADDRESSES_TO_FETCH): Promise<string[]> {
        const initialDerivedKeyInfo = await this._initialDerivedKeyInfoAsync();
        const derivedKeyInfos = walletUtils.calculateDerivedHDKeyInfos(initialDerivedKeyInfo, numberOfAccounts);
        const accounts = _.map(derivedKeyInfos, k => k.address);
        return accounts;
    }
    /**
     * Signs a transaction on the Ledger with the account specificed by the `from` field in txParams.
     * If you've added the LedgerSubprovider to your app's provider, you can simply send an `eth_sendTransaction`
     * JSON RPC request, and this method will be called auto-magically. If you are not using this via a ProviderEngine
     * instance, you can call it directly.
     * @param txParams Parameters of the transaction to sign
     * @return Signed transaction hex string
     */
    public async signTransactionAsync(txParams: PartialTxParams): Promise<string> {
        LedgerSubprovider._validateTxParams(txParams);
        if (_.isUndefined(txParams.from) || !addressUtils.isAddress(txParams.from)) {
            throw new Error(WalletSubproviderErrors.FromAddressMissingOrInvalid);
        }
        const initialDerivedKeyInfo = await this._initialDerivedKeyInfoAsync();
        const derivedKeyInfo = this._findDerivedKeyInfoForAddress(initialDerivedKeyInfo, txParams.from);

        this._ledgerClientIfExists = await this._createLedgerClientAsync();

        const tx = new EthereumTx(txParams);

        // Set the EIP155 bits
        const vIndex = 6;
        tx.raw[vIndex] = Buffer.from([this._networkId]); // v
        const rIndex = 7;
        tx.raw[rIndex] = Buffer.from([]); // r
        const sIndex = 8;
        tx.raw[sIndex] = Buffer.from([]); // s

        const txHex = tx.serialize().toString('hex');
        try {
            const fullDerivationPath = derivedKeyInfo.derivationPath;
            const result = await this._ledgerClientIfExists.signTransaction(fullDerivationPath, txHex);
            // Store signature in transaction
            tx.r = Buffer.from(result.r, 'hex');
            tx.s = Buffer.from(result.s, 'hex');
            tx.v = Buffer.from(result.v, 'hex');

            // EIP155: v should be chain_id * 2 + {35, 36}
            const eip55Constant = 35;
            const signedChainId = Math.floor((tx.v[0] - eip55Constant) / 2);
            if (signedChainId !== this._networkId) {
                await this._destroyLedgerClientAsync();
                const err = new Error(LedgerSubproviderErrors.TooOldLedgerFirmware);
                throw err;
            }

            const signedTxHex = `0x${tx.serialize().toString('hex')}`;
            await this._destroyLedgerClientAsync();
            return signedTxHex;
        } catch (err) {
            await this._destroyLedgerClientAsync();
            throw err;
        }
    }
    /**
     * Sign a personal Ethereum signed message. The signing account will be the account
     * associated with the provided address.
     * The Ledger adds the Ethereum signed message prefix on-device.  If you've added
     * the LedgerSubprovider to your app's provider, you can simply send an `eth_sign`
     * or `personal_sign` JSON RPC request, and this method will be called auto-magically.
     * If you are not using this via a ProviderEngine instance, you can call it directly.
     * @param data Hex string message to sign
     * @param address Address of the account to sign with
     * @return Signature hex string (order: rsv)
     */
    public async signPersonalMessageAsync(data: string, address: string): Promise<string> {
        if (_.isUndefined(data)) {
            throw new Error(WalletSubproviderErrors.DataMissingForSignPersonalMessage);
        }
        assert.isHexString('data', data);
        assert.isETHAddressHex('address', address);
        const initialDerivedKeyInfo = await this._initialDerivedKeyInfoAsync();
        const derivedKeyInfo = this._findDerivedKeyInfoForAddress(initialDerivedKeyInfo, address);

        this._ledgerClientIfExists = await this._createLedgerClientAsync();
        try {
            const fullDerivationPath = derivedKeyInfo.derivationPath;
            const result = await this._ledgerClientIfExists.signPersonalMessage(
                fullDerivationPath,
                ethUtil.stripHexPrefix(data),
            );
            const lowestValidV = 27;
            const v = result.v - lowestValidV;
            const hexBase = 16;
            let vHex = v.toString(hexBase);
            if (vHex.length < 2) {
                vHex = `0${v}`;
            }
            const signature = `0x${result.r}${result.s}${vHex}`;
            await this._destroyLedgerClientAsync();
            return signature;
        } catch (err) {
            await this._destroyLedgerClientAsync();
            throw err;
        }
    }
    private async _createLedgerClientAsync(): Promise<LedgerEthereumClient> {
        await this._connectionLock.acquire();
        if (!_.isUndefined(this._ledgerClientIfExists)) {
            this._connectionLock.release();
            throw new Error(LedgerSubproviderErrors.MultipleOpenConnectionsDisallowed);
        }
        const ledgerEthereumClient = await this._ledgerEthereumClientFactoryAsync();
        this._connectionLock.release();
        return ledgerEthereumClient;
    }
    private async _destroyLedgerClientAsync(): Promise<void> {
        await this._connectionLock.acquire();
        if (_.isUndefined(this._ledgerClientIfExists)) {
            this._connectionLock.release();
            return;
        }
        await this._ledgerClientIfExists.transport.close();
        this._ledgerClientIfExists = undefined;
        this._connectionLock.release();
    }
    private async _initialDerivedKeyInfoAsync(): Promise<DerivedHDKeyInfo> {
        this._ledgerClientIfExists = await this._createLedgerClientAsync();

        const parentKeyDerivationPath = `m/${this._baseDerivationPath}`;
        let ledgerResponse;
        try {
            ledgerResponse = await this._ledgerClientIfExists.getAddress(
                parentKeyDerivationPath,
                this._shouldAlwaysAskForConfirmation,
                SHOULD_GET_CHAIN_CODE,
            );
        } finally {
            await this._destroyLedgerClientAsync();
        }
        const hdKey = new HDNode();
        hdKey.publicKey = new Buffer(ledgerResponse.publicKey, 'hex');
        hdKey.chainCode = new Buffer(ledgerResponse.chainCode, 'hex');
        const address = walletUtils.addressOfHDKey(hdKey);
        const initialDerivedKeyInfo = {
            hdKey,
            address,
            derivationPath: parentKeyDerivationPath,
            baseDerivationPath: this._baseDerivationPath,
        };
        return initialDerivedKeyInfo;
    }
    private _findDerivedKeyInfoForAddress(initalHDKey: DerivedHDKeyInfo, address: string): DerivedHDKeyInfo {
        const matchedDerivedKeyInfo = walletUtils.findDerivedKeyInfoForAddressIfExists(
            address,
            initalHDKey,
            this._addressSearchLimit,
        );
        if (_.isUndefined(matchedDerivedKeyInfo)) {
            throw new Error(`${WalletSubproviderErrors.AddressNotFound}: ${address}`);
        }
        return matchedDerivedKeyInfo;
    }
}