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
|
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 {ecSignatureSchema} from './schemas/ec_signature_schema';
import {TokenWrapper} from './contract_wrappers/token_wrapper';
import {ECSignature, ZeroExError, Order, SignedOrder} from './types';
import * as ExchangeArtifacts from './artifacts/Exchange.json';
import {SchemaValidator} from './utils/schema_validator';
import {orderSchema} from './schemas/order_schemas';
// Customize our BigNumber instances
bigNumberConfigs.configure();
export class ZeroEx {
public static NULL_ADDRESS = constants.NULL_ADDRESS;
public exchange: ExchangeWrapper;
public tokenRegistry: TokenRegistryWrapper;
public token: TokenWrapper;
private web3Wrapper: Web3Wrapper;
/**
* Verifies that the elliptic curve signature `signature` was generated
* by signing `dataHex` with the private key corresponding to the `signerAddressHex` address.
*/
public static isValidSignature(dataHex: string, signature: ECSignature, signerAddressHex: string): boolean {
assert.isHexString('dataHex', dataHex);
assert.doesConformToSchema('signature', signature, ecSignatureSchema);
assert.isETHAddressHex('signerAddressHex', signerAddressHex);
const dataBuff = ethUtil.toBuffer(dataHex);
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 === signerAddressHex;
} catch (err) {
return false;
}
}
/**
* Generates pseudo-random 256 bit salt.
* The salt is used to ensure that the 0x order generated has a unique orderHash that does
* not collide with any other outstanding orders.
*/
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.
*/
public static isValidOrderHash(orderHashHex: 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('orderHashHex', orderHashHex);
const isValidOrderHash = utils.isValidOrderHash(orderHashHex);
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.
*/
public static toUnitAmount(amount: BigNumber.BigNumber, numDecimals: number): BigNumber.BigNumber {
assert.isBigNumber('amount', amount);
assert.isNumber('numDecimals', numDecimals);
const aUnit = new BigNumber(10).pow(numDecimals);
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
*/
public static toBaseUnitAmount(amount: BigNumber.BigNumber, numDecimals: number): BigNumber.BigNumber {
assert.isBigNumber('amount', amount);
assert.isNumber('numDecimals', numDecimals);
const unit = new BigNumber(10).pow(numDecimals);
const baseUnitAmount = amount.times(unit);
return baseUnitAmount;
}
constructor(web3: Web3) {
this.web3Wrapper = new Web3Wrapper(web3);
this.token = new TokenWrapper(this.web3Wrapper);
this.exchange = new ExchangeWrapper(this.web3Wrapper, this.token);
this.tokenRegistry = new TokenRegistryWrapper(this.web3Wrapper);
}
/**
* Sets a new provider for the web3 instance used by 0x.js
*/
public async setProviderAsync(provider: Web3.Provider) {
this.web3Wrapper.setProvider(provider);
await this.exchange.invalidateContractInstanceAsync();
this.tokenRegistry.invalidateContractInstance();
this.token.invalidateContractInstances();
}
/**
* Get addresses via the supplied web3 instance available for sending transactions.
*/
public async getAvailableAddressesAsync(): Promise<string[]> {
const availableAddresses = await this.web3Wrapper.getAvailableAddressesAsync();
return availableAddresses;
}
/**
* Computes the orderHash for a given order and returns it as a hex encoded string.
*/
public async getOrderHashHexAsync(order: Order|SignedOrder): Promise<string> {
assert.doesConformToSchema('order', order, orderSchema);
const exchangeContractAddr = await this.getExchangeAddressAsync();
const orderHashHex = utils.getOrderHashHex(order, exchangeContractAddr);
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
*/
public async signOrderHashAsync(orderHashHex: string, signerAddress: string): Promise<ECSignature> {
assert.isHexString('orderHashHex', orderHashHex);
await assert.isSenderAddressAsync('signerAddress', signerAddress, this.web3Wrapper);
let msgHashHex;
const nodeVersion = await this.web3Wrapper.getNodeVersionAsync();
const isParityNode = utils.isParityNode(nodeVersion);
if (isParityNode) {
// Parity node adds the personalMessage prefix itself
msgHashHex = orderHashHex;
} else {
const orderHashBuff = ethUtil.toBuffer(orderHashHex);
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(orderHashHex, ecSignature, signerAddress);
if (!isValidSignature) {
throw new Error(ZeroExError.INVALID_SIGNATURE);
}
return ecSignature;
}
private async getExchangeAddressAsync() {
const networkIdIfExists = await this.web3Wrapper.getNetworkIdIfExistsAsync();
const exchangeNetworkConfigsIfExists = _.isUndefined(networkIdIfExists) ?
undefined :
(ExchangeArtifacts as any).networks[networkIdIfExists];
if (_.isUndefined(exchangeNetworkConfigsIfExists)) {
throw new Error(ZeroExError.CONTRACT_NOT_DEPLOYED_ON_NETWORK);
}
const exchangeAddress = exchangeNetworkConfigsIfExists.address;
return exchangeAddress;
}
}
|
