aboutsummaryrefslogtreecommitdiffstats
path: root/src/0x.ts
blob: d790ca38e402449fca2726bdfa3d96de47b5c0bb (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
248
249
250
251
252
253
254
255
256
import * as _ from 'lodash';
import * as BigNumber from 'bignumber.js';
import {bigNumberConfigs} from './bignumber_config';
import * as ethUtil from 'ethereumjs-util';
import contract = require('truffle-contract');
import * as Web3 from 'web3';
import findVersions = require('find-versions');
import compareVersions = require('compare-versions');
import {Web3Wrapper} from './web3_wrapper';
import {constants} from './utils/constants';
import {utils} from './utils/utils';
import {assert} from './utils/assert';
import {ExchangeWrapper} from './contract_wrappers/exchange_wrapper';
import {TokenRegistryWrapper} from './contract_wrappers/token_registry_wrapper';
import {EtherTokenWrapper} from './contract_wrappers/ether_token_wrapper';
import {ecSignatureSchema} from './schemas/ec_signature_schema';
import {TokenWrapper} from './contract_wrappers/token_wrapper';
import {ProxyWrapper} from './contract_wrappers/proxy_wrapper';
import {ECSignature, ZeroExError, Order, SignedOrder, Web3Provider} from './types';
import {orderSchema, orderHashSchema} from './schemas/order_schemas';
import {SchemaValidator} from './utils/schema_validator';

// Customize our BigNumber instances
bigNumberConfigs.configure();

/**
 * The ZeroEx class is the single entry-point into the 0x.js library. It contains all of the library's functionality
 * and all calls to the library should be made through a ZeroEx instance.
 */
export class ZeroEx {
    /**
     * When creating an order without a specified taker or feeRecipient you must supply the Solidity
     * address null type (as opposed to Javascripts `null`, `undefined` or empty string). We expose
     * this constant for your convenience.
     */
    public static NULL_ADDRESS = constants.NULL_ADDRESS;

    /**
     * An instance of the ExchangeWrapper class containing methods for interacting with the 0x Exchange smart contract.
     */
    public exchange: ExchangeWrapper;
    /**
     * An instance of the TokenRegistryWrapper class containing methods for interacting with the 0x
     * TokenRegistry smart contract.
     */
    public tokenRegistry: TokenRegistryWrapper;
    /**
     * An instance of the TokenWrapper class containing methods for interacting with any ERC20 token smart contract.
     */
    public token: TokenWrapper;
    /**
     * An instance of the EtherTokenWrapper class containing methods for interacting with the
     * wrapped ETH ERC20 token smart contract.
     */
    public etherToken: EtherTokenWrapper;
    /**
     * An instance of the ProxyWrapper class containing methods for interacting with the
     * proxy smart contract.
     */
    public proxy: ProxyWrapper;
    private _web3Wrapper: Web3Wrapper;
    /**
     * Verifies that the elliptic curve signature `signature` was generated
     * by signing `data` with the private key corresponding to the `signerAddress` address.
     * @param   data          The hex encoded data signed by the supplied signature.
     * @param   signature     An object containing the elliptic curve signature parameters.
     * @param   signerAddress The hex encoded address that signed the data, producing the supplied signature.
     * @return  Whether the signature is valid for the supplied signerAddress and data.
     */
    public static isValidSignature(data: string, signature: ECSignature, signerAddress: string): boolean {
        assert.isHexString('data', data);
        assert.doesConformToSchema('signature', signature, ecSignatureSchema);
        assert.isETHAddressHex('signerAddress', signerAddress);

        const dataBuff = ethUtil.toBuffer(data);
        const msgHashBuff = ethUtil.hashPersonalMessage(dataBuff);
        try {
            const pubKey = ethUtil.ecrecover(
                msgHashBuff,
                signature.v,
                ethUtil.toBuffer(signature.r),
                ethUtil.toBuffer(signature.s));
            const retrievedAddress = ethUtil.bufferToHex(ethUtil.pubToAddress(pubKey));
            return retrievedAddress === signerAddress;
        } catch (err) {
            return false;
        }
    }
    /**
     * Generates a pseudo-random 256-bit salt.
     * The salt can be included in an 0x order, ensuring that the order generates a unique orderHash
     * and will not collide with other outstanding orders that are identical in all other parameters.
     * @return  A pseudo-random 256-bit number that can be used as a salt.
     */
    public static generatePseudoRandomSalt(): BigNumber.BigNumber {
        // BigNumber.random returns a pseudo-random number between 0 & 1 with a passed in number of decimal places.
        // Source: https://mikemcl.github.io/bignumber.js/#random
        const randomNumber = BigNumber.random(constants.MAX_DIGITS_IN_UNSIGNED_256_INT);
        const factor = new BigNumber(10).pow(constants.MAX_DIGITS_IN_UNSIGNED_256_INT - 1);
        const salt = randomNumber.times(factor).round();
        return salt;
    }
    /**
     * Checks if the supplied hex encoded order hash is valid.
     * Note: Valid means it has the expected format, not that an order with the orderHash exists.
     * Use this method when processing orderHashes submitted as user input.
     * @param   orderHash    Hex encoded orderHash.
     * @return  Whether the supplied orderHash has the expected format.
     */
    public static isValidOrderHash(orderHash: string): boolean {
        // Since this method can be called to check if any arbitrary string conforms to an orderHash's
        // format, we only assert that we were indeed passed a string.
        assert.isString('orderHash', orderHash);
        const schemaValidator = new SchemaValidator();
        const isValidOrderHash = schemaValidator.validate(orderHash, orderHashSchema).valid;
        return isValidOrderHash;
    }
    /**
     * A unit amount is defined as the amount of a token above the specified decimal places (integer part).
     * E.g: If a currency has 18 decimal places, 1e18 or one quintillion of the currency is equivalent
     * to 1 unit.
     * @param   amount      The amount in baseUnits that you would like converted to units.
     * @param   decimals    The number of decimal places the unit amount has.
     * @return  The amount in units.
     */
    public static toUnitAmount(amount: BigNumber.BigNumber, decimals: number): BigNumber.BigNumber {
        assert.isBigNumber('amount', amount);
        assert.isNumber('decimals', decimals);

        const aUnit = new BigNumber(10).pow(decimals);
        const unit = amount.div(aUnit);
        return unit;
    }
    /**
     * A baseUnit is defined as the smallest denomination of a token. An amount expressed in baseUnits
     * is the amount expressed in the smallest denomination.
     * E.g: 1 unit of a token with 18 decimal places is expressed in baseUnits as 1000000000000000000
     * @param   amount      The amount of units that you would like converted to baseUnits.
     * @param   decimals    The number of decimal places the unit amount has.
     * @return  The amount in baseUnits.
     */
    public static toBaseUnitAmount(amount: BigNumber.BigNumber, decimals: number): BigNumber.BigNumber {
        assert.isBigNumber('amount', amount);
        assert.isNumber('decimals', decimals);

        const unit = new BigNumber(10).pow(decimals);
        const baseUnitAmount = amount.times(unit);
        return baseUnitAmount;
    }
    /**
     * Instantiates a new ZeroEx instance that provides the public interface to the 0x.js library.
     * @param   provider    The Web3.js Provider instance you would like the 0x.js library to use for interacting with
     *                      the Ethereum network.
     * @return  An instance of the 0x.js ZeroEx class.
     */
    constructor(provider: Web3Provider) {
        this._web3Wrapper = new Web3Wrapper(provider);
        this.token = new TokenWrapper(this._web3Wrapper);
        this.proxy = new ProxyWrapper(this._web3Wrapper);
        this.exchange = new ExchangeWrapper(this._web3Wrapper, this.token, this.proxy);
        this.tokenRegistry = new TokenRegistryWrapper(this._web3Wrapper);
        this.etherToken = new EtherTokenWrapper(this._web3Wrapper, this.token);
    }
    /**
     * Sets a new provider for the web3 instance used by 0x.js. Updating the provider will stop all
     * subscriptions so you will need to re-subscribe to all events relevant to your app after this call.
     * @param   provider    The Web3Provider you would like the 0x.js library to use from now on.
     */
    public async setProviderAsync(provider: Web3Provider) {
        this._web3Wrapper.setProvider(provider);
        await (this.exchange as any)._invalidateContractInstancesAsync();
        (this.tokenRegistry as any)._invalidateContractInstance();
        await (this.token as any)._invalidateContractInstancesAsync();
        (this.proxy as any)._invalidateContractInstance();
        (this.etherToken as any)._invalidateContractInstance();
    }
    /**
     * Get user Ethereum addresses available through the supplied web3 instance available for sending transactions.
     * @return  An array of available user Ethereum addresses.
     */
    public async getAvailableAddressesAsync(): Promise<string[]> {
        const availableAddresses = await this._web3Wrapper.getAvailableAddressesAsync();
        return availableAddresses;
    }
    /**
     * Computes the orderHash for a supplied order.
     * @param   order   An object that conforms to the Order or SignedOrder interface definitions.
     * @return  The resulting orderHash from hashing the supplied order.
     */
    public getOrderHashHex(order: Order|SignedOrder): string {
        assert.doesConformToSchema('order', order, orderSchema);
        const orderHashHex = utils.getOrderHashHex(order);
        return orderHashHex;
    }
    /**
     * Signs an orderHash and returns it's elliptic curve signature.
     * This method currently supports TestRPC, Geth and Parity above and below V1.6.6
     * @param   orderHash       Hex encoded orderHash to sign.
     * @param   signerAddress   The hex encoded Ethereum address you wish to sign it with. This address
     *          must be available via the Web3.Provider supplied to 0x.js.
     * @return  An object containing the Elliptic curve signature parameters generated by signing the orderHash.
     */
    public async signOrderHashAsync(orderHash: string, signerAddress: string): Promise<ECSignature> {
        assert.isHexString('orderHash', orderHash);
        await assert.isSenderAddressAsync('signerAddress', signerAddress, this._web3Wrapper);

        let msgHashHex;
        const nodeVersion = await this._web3Wrapper.getNodeVersionAsync();
        const isParityNode = utils.isParityNode(nodeVersion);
        const isTestRpc = utils.isTestRpc(nodeVersion);
        if (isParityNode || isTestRpc) {
            // Parity and TestRpc nodes add the personalMessage prefix itself
            msgHashHex = orderHash;
        } else {
            const orderHashBuff = ethUtil.toBuffer(orderHash);
            const msgHashBuff = ethUtil.hashPersonalMessage(orderHashBuff);
            msgHashHex = ethUtil.bufferToHex(msgHashBuff);
        }

        const signature = await this._web3Wrapper.signTransactionAsync(signerAddress, msgHashHex);

        let signatureData;
        const [nodeVersionNumber] = findVersions(nodeVersion);
        // Parity v1.6.6 and earlier returns the signatureData as vrs instead of rsv as Geth does
        // Later versions return rsv but for the time being we still want to support version < 1.6.6
        // Date: May 23rd 2017
        const latestParityVersionWithVRS = '1.6.6';
        const isVersionBeforeParityFix = compareVersions(nodeVersionNumber, latestParityVersionWithVRS) <= 0;
        if (isParityNode && isVersionBeforeParityFix) {
            const signatureBuffer = ethUtil.toBuffer(signature);
            let v = signatureBuffer[0];
            if (v < 27) {
                v += 27;
            }
            signatureData = {
                v,
                r: signatureBuffer.slice(1, 33),
                s: signatureBuffer.slice(33, 65),
            };
        } else {
            signatureData = ethUtil.fromRpcSig(signature);
        }

        const {v, r, s} = signatureData;
        const ecSignature: ECSignature = {
            v,
            r: ethUtil.bufferToHex(r),
            s: ethUtil.bufferToHex(s),
        };
        const isValidSignature = ZeroEx.isValidSignature(orderHash, ecSignature, signerAddress);
        if (!isValidSignature) {
            throw new Error(ZeroExError.INVALID_SIGNATURE);
        }
        return ecSignature;
    }
}