1 files changed, 172 insertions, 0 deletions
diff --git a/packages/website/ts/subproviders/ledger_wallet_subprovider_factory.ts b/packages/website/ts/subproviders/ledger_wallet_subprovider_factory.ts
new file mode 100644
index 000000000..df0c5a4db
--- /dev/null
+++ b/packages/website/ts/subproviders/ledger_wallet_subprovider_factory.ts
@@ -0,0 +1,172 @@
+import * as _ from 'lodash';
+import Web3 = require('web3');
+import * as EthereumTx from 'ethereumjs-tx';
+import ethUtil = require('ethereumjs-util');
+import * as ledger from 'ledgerco';
+import HookedWalletSubprovider = require('web3-provider-engine/subproviders/hooked-wallet');
+import {constants} from 'ts/utils/constants';
+import {LedgerEthConnection, SignPersonalMessageParams, TxParams} from 'ts/types';
+
+const NUM_ADDRESSES_TO_FETCH = 10;
+const ASK_FOR_ON_DEVICE_CONFIRMATION = false;
+const SHOULD_GET_CHAIN_CODE = false;
+
+export class LedgerWallet {
+    public isU2FSupported: boolean;
+    public getAccounts: (callback: (err: Error, accounts: string[]) => void) => void;
+    public signMessage: (msgParams: SignPersonalMessageParams,
+                         callback: (err: Error, result?: string) => void) => void;
+    public signTransaction: (txParams: TxParams,
+                             callback: (err: Error, result?: string) => void) => void;
+    private getNetworkId: () => number;
+    private path: string;
+    private pathIndex: number;
+    private ledgerEthConnection: LedgerEthConnection;
+    private accounts: string[];
+    constructor(getNetworkIdFn: () => number) {
+        this.path = constants.DEFAULT_DERIVATION_PATH;
+        this.pathIndex = 0;
+        this.isU2FSupported = false;
+        this.getNetworkId = getNetworkIdFn;
+        this.getAccounts = this.getAccountsAsync.bind(this);
+        this.signMessage = this.signPersonalMessageAsync.bind(this);
+        this.signTransaction = this.signTransactionAsync.bind(this);
+    }
+    public getPath(): string {
+        return this.path;
+    }
+    public setPath(derivationPath: string) {
+        this.path = derivationPath;
+        // HACK: Must re-assign getAccounts, signMessage and signTransaction since they were
+        // previously bound to old values of this.path
+        this.getAccounts = this.getAccountsAsync.bind(this);
+        this.signMessage = this.signPersonalMessageAsync.bind(this);
+        this.signTransaction = this.signTransactionAsync.bind(this);
+    }
+    public setPathIndex(pathIndex: number) {
+        this.pathIndex = pathIndex;
+        // HACK: Must re-assign signMessage & signTransaction since they it was previously bound to
+        // old values of this.path
+        this.signMessage = this.signPersonalMessageAsync.bind(this);
+        this.signTransaction = this.signTransactionAsync.bind(this);
+    }
+    public async getAccountsAsync(callback: (err: Error, accounts: string[]) => void) {
+        if (!_.isUndefined(this.ledgerEthConnection)) {
+            callback(null, []);
+            return;
+        }
+        this.ledgerEthConnection = await this.createLedgerConnectionAsync();
+
+        const accounts = [];
+        for (let i = 0; i < NUM_ADDRESSES_TO_FETCH; i++) {
+            try {
+                const derivationPath = `${this.path}/${i}`;
+                const result = await this.ledgerEthConnection.getAddress_async(
+                    derivationPath, ASK_FOR_ON_DEVICE_CONFIRMATION, SHOULD_GET_CHAIN_CODE,
+                );
+                accounts.push(result.address.toLowerCase());
+            } catch (err) {
+                await this.closeLedgerConnectionAsync();
+                callback(err, null);
+                return;
+            }
+        }
+
+        await this.closeLedgerConnectionAsync();
+        callback(null, accounts);
+    }
+    public async signTransactionAsync(txParams: TxParams, callback: (err: Error, result?: string) => void) {
+        const tx = new EthereumTx(txParams);
+
+        const networkId = this.getNetworkId();
+        const chainId = networkId; // Same thing
+
+        // Set the EIP155 bits
+        tx.raw[6] = Buffer.from([chainId]);  // v
+        tx.raw[7] = Buffer.from([]);         // r
+        tx.raw[8] = Buffer.from([]);         // s
+
+        const txHex = tx.serialize().toString('hex');
+
+        this.ledgerEthConnection = await this.createLedgerConnectionAsync();
+
+        try {
+            const derivationPath = this.getDerivationPath();
+            const result = await this.ledgerEthConnection.signTransaction_async(derivationPath, txHex);
+
+            // Store signature in transaction
+            tx.v = new Buffer(result.v, 'hex');
+            tx.r = new Buffer(result.r, 'hex');
+            tx.s = new Buffer(result.s, 'hex');
+
+            // EIP155: v should be chain_id * 2 + {35, 36}
+            const signedChainId = Math.floor((tx.v[0] - 35) / 2);
+            if (signedChainId !== chainId) {
+                const err = new Error('TOO_OLD_LEDGER_FIRMWARE');
+                callback(err, null);
+                return;
+            }
+
+            const signedTxHex = `0x${tx.serialize().toString('hex')}`;
+            await this.closeLedgerConnectionAsync();
+            callback(null, signedTxHex);
+        } catch (err) {
+            await this.closeLedgerConnectionAsync();
+            callback(err, null);
+        }
+    }
+    public async signPersonalMessageAsync(msgParams: SignPersonalMessageParams,
+                                          callback: (err: Error, result?: string) => void) {
+        if (!_.isUndefined(this.ledgerEthConnection)) {
+            callback(new Error('Another request is in progress.'));
+            return;
+        }
+        this.ledgerEthConnection = await this.createLedgerConnectionAsync();
+
+        try {
+            const derivationPath = this.getDerivationPath();
+            const result = await this.ledgerEthConnection.signPersonalMessage_async(
+                derivationPath, ethUtil.stripHexPrefix(msgParams.data),
+            );
+            const v = _.parseInt(result.v) - 27;
+            let vHex = v.toString(16);
+            if (vHex.length < 2) {
+                vHex = `0${v}`;
+            }
+            const signature = `0x${result.r}${result.s}${vHex}`;
+            await this.closeLedgerConnectionAsync();
+            callback(null, signature);
+        } catch (err) {
+            await this.closeLedgerConnectionAsync();
+            callback(err, null);
+        }
+    }
+    private async createLedgerConnectionAsync() {
+        if (!_.isUndefined(this.ledgerEthConnection)) {
+            throw new Error('Multiple open connections to the Ledger disallowed.');
+        }
+        const ledgerConnection = await ledger.comm_u2f.create_async();
+        const ledgerEthConnection = new ledger.eth(ledgerConnection);
+        return ledgerEthConnection;
+    }
+    private async closeLedgerConnectionAsync() {
+        if (_.isUndefined(this.ledgerEthConnection)) {
+            return;
+        }
+        await this.ledgerEthConnection.comm.close_async();
+        this.ledgerEthConnection = undefined;
+    }
+    private getDerivationPath() {
+        const derivationPath = `${this.path}/${this.pathIndex}`;
+        return derivationPath;
+    }
+}
+
+export const ledgerWalletSubproviderFactory = (getNetworkIdFn: () => number): LedgerWallet => {
+    const ledgerWallet = new LedgerWallet(getNetworkIdFn);
+    const ledgerWalletSubprovider = new HookedWalletSubprovider(ledgerWallet) as LedgerWallet;
+    ledgerWalletSubprovider.getPath = ledgerWallet.getPath.bind(ledgerWallet);
+    ledgerWalletSubprovider.setPath = ledgerWallet.setPath.bind(ledgerWallet);
+    ledgerWalletSubprovider.setPathIndex = ledgerWallet.setPathIndex.bind(ledgerWallet);
+    return ledgerWalletSubprovider;
+};