Merge pull request #1576 from 0xProject/feat/transaction-hash

Add transactionHashUtils to order-utils package

23 files changed, 298 insertions, 94 deletions

diff --git a/contracts/exchange/test/transactions.ts b/contracts/exchange/test/transactions.ts
index 613953493..4f8c07579 100644
--- a/contracts/exchange/test/transactions.ts
+++ b/contracts/exchange/test/transactions.ts
@@ -8,14 +8,13 @@ import {
     OrderFactory,
     orderUtils,
     provider,
-    SignedTransaction,
     TransactionFactory,
     txDefaults,
     web3Wrapper,
 } from '@0x/contracts-test-utils';
 import { BlockchainLifecycle } from '@0x/dev-utils';
 import { assetDataUtils, generatePseudoRandomSalt } from '@0x/order-utils';
-import { OrderWithoutExchangeAddress, RevertReason, SignedOrder } from '@0x/types';
+import { OrderWithoutExchangeAddress, RevertReason, SignedOrder, SignedZeroExTransaction } from '@0x/types';
 import { BigNumber } from '@0x/utils';
 import * as chai from 'chai';
 import * as _ from 'lodash';
@@ -41,7 +40,7 @@ describe('Exchange transactions', () => {
 
     let erc20Balances: ERC20BalancesByOwner;
     let signedOrder: SignedOrder;
-    let signedTx: SignedTransaction;
+    let signedTx: SignedZeroExTransaction;
     let orderWithoutExchangeAddress: OrderWithoutExchangeAddress;
     let orderFactory: OrderFactory;
     let makerTransactionFactory: TransactionFactory;
diff --git a/contracts/exchange/test/utils/exchange_wrapper.ts b/contracts/exchange/test/utils/exchange_wrapper.ts
index eca535c65..03c37c4a9 100644
--- a/contracts/exchange/test/utils/exchange_wrapper.ts
+++ b/contracts/exchange/test/utils/exchange_wrapper.ts
@@ -1,14 +1,7 @@
 import { artifacts as erc20Artifacts } from '@0x/contracts-erc20';
 import { artifacts as erc721Artifacts } from '@0x/contracts-erc721';
-import {
-    FillResults,
-    formatters,
-    LogDecoder,
-    OrderInfo,
-    orderUtils,
-    SignedTransaction,
-} from '@0x/contracts-test-utils';
-import { SignedOrder } from '@0x/types';
+import { FillResults, formatters, LogDecoder, OrderInfo, orderUtils } from '@0x/contracts-test-utils';
+import { SignedOrder, SignedZeroExTransaction } from '@0x/types';
 import { AbiEncoder, BigNumber } from '@0x/utils';
 import { Web3Wrapper } from '@0x/web3-wrapper';
 import { MethodAbi, Provider, TransactionReceiptWithDecodedLogs } from 'ethereum-types';
@@ -206,7 +199,7 @@ export class ExchangeWrapper {
         return tx;
     }
     public async executeTransactionAsync(
-        signedTx: SignedTransaction,
+        signedTx: SignedZeroExTransaction,
         from: string,
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const txHash = await this._exchange.executeTransaction.sendTransactionAsync(
diff --git a/contracts/test-utils/CHANGELOG.json b/contracts/test-utils/CHANGELOG.json
index 51b726e82..0c6174313 100644
--- a/contracts/test-utils/CHANGELOG.json
+++ b/contracts/test-utils/CHANGELOG.json
@@ -5,6 +5,10 @@
             {
                 "note": "Upgrade the bignumber.js to v8.0.2",
                 "pr": 1517
+            },
+            {
+                "note": "Import `ZeroExTransaction` type instead of using type defined in this package",
+                "pr": 1576
             }
         ],
         "timestamp": 1549373905
diff --git a/contracts/test-utils/src/index.ts b/contracts/test-utils/src/index.ts
index 7880de0bf..5ac927e47 100644
--- a/contracts/test-utils/src/index.ts
+++ b/contracts/test-utils/src/index.ts
@@ -31,7 +31,6 @@ export {
     MarketBuyOrders,
     MarketSellOrders,
     ERC721TokenIdsByOwner,
-    SignedTransaction,
     OrderStatus,
     AllowanceAmountScenario,
     AssetDataScenario,
diff --git a/contracts/test-utils/src/transaction_factory.ts b/contracts/test-utils/src/transaction_factory.ts
index dbab3ade4..e6cd4c23f 100644
--- a/contracts/test-utils/src/transaction_factory.ts
+++ b/contracts/test-utils/src/transaction_factory.ts
@@ -1,10 +1,8 @@
-import { eip712Utils, generatePseudoRandomSalt } from '@0x/order-utils';
-import { SignatureType } from '@0x/types';
-import { signTypedDataUtils } from '@0x/utils';
+import { generatePseudoRandomSalt, transactionHashUtils } from '@0x/order-utils';
+import { SignatureType, SignedZeroExTransaction } from '@0x/types';
 import * as ethUtil from 'ethereumjs-util';
 
 import { signingUtils } from './signing_utils';
-import { SignedTransaction } from './types';
 
 export class TransactionFactory {
     private readonly _signerBuff: Buffer;
@@ -15,23 +13,25 @@ export class TransactionFactory {
         this._exchangeAddress = exchangeAddress;
         this._signerBuff = ethUtil.privateToAddress(this._privateKey);
     }
-    public newSignedTransaction(data: string, signatureType: SignatureType = SignatureType.EthSign): SignedTransaction {
+    public newSignedTransaction(
+        data: string,
+        signatureType: SignatureType = SignatureType.EthSign,
+    ): SignedZeroExTransaction {
         const salt = generatePseudoRandomSalt();
         const signerAddress = `0x${this._signerBuff.toString('hex')}`;
-        const executeTransactionData = {
+        const transaction = {
             salt,
             signerAddress,
             data,
+            verifyingContractAddress: this._exchangeAddress,
         };
 
-        const typedData = eip712Utils.createZeroExTransactionTypedData(executeTransactionData, this._exchangeAddress);
-        const eip712MessageBuffer = signTypedDataUtils.generateTypedDataHash(typedData);
-        const signature = signingUtils.signMessage(eip712MessageBuffer, this._privateKey, signatureType);
-        const signedTx = {
-            exchangeAddress: this._exchangeAddress,
+        const transactionHashBuffer = transactionHashUtils.getTransactionHashBuffer(transaction);
+        const signature = signingUtils.signMessage(transactionHashBuffer, this._privateKey, signatureType);
+        const signedTransaction = {
+            ...transaction,
             signature: `0x${signature.toString('hex')}`,
-            ...executeTransactionData,
         };
-        return signedTx;
+        return signedTransaction;
     }
 }
diff --git a/contracts/test-utils/src/types.ts b/contracts/test-utils/src/types.ts
index 60cb2b102..16c3a9f3d 100644
--- a/contracts/test-utils/src/types.ts
+++ b/contracts/test-utils/src/types.ts
@@ -107,14 +107,6 @@ export enum ContractName {
     BalanceThresholdFilter = 'BalanceThresholdFilter',
 }
 
-export interface SignedTransaction {
-    exchangeAddress: string;
-    salt: BigNumber;
-    signerAddress: string;
-    data: string;
-    signature: string;
-}
-
 export interface TransferAmountsByMatchOrders {
     // Left Maker
     amountBoughtByLeftMaker: BigNumber;
diff --git a/packages/contract-wrappers/CHANGELOG.json b/packages/contract-wrappers/CHANGELOG.json
index 413563f80..ae3176537 100644
--- a/packages/contract-wrappers/CHANGELOG.json
+++ b/packages/contract-wrappers/CHANGELOG.json
@@ -1,10 +1,18 @@
 [
     {
-        "version": "6.0.1",
+        "version": "7.0.0",
         "changes": [
             {
                 "note": "Fix OrderValidatorWrapper constructor to use the correct address",
                 "pr": 1568
+            },
+            {
+                "note": "Use new `ZeroExTransaction` interface",
+                "pr": 1576
+            },
+            {
+                "note": "Rename `getTransactionHex` to `getTransactionHashHex`",
+                "pr": 1576
             }
         ],
         "timestamp": 1549373905
diff --git a/packages/contract-wrappers/src/utils/transaction_encoder.ts b/packages/contract-wrappers/src/utils/transaction_encoder.ts
index 0cf08a8fe..307487a9b 100644
--- a/packages/contract-wrappers/src/utils/transaction_encoder.ts
+++ b/packages/contract-wrappers/src/utils/transaction_encoder.ts
@@ -1,9 +1,9 @@
 import { ExchangeContract } from '@0x/abi-gen-wrappers';
 
 import { schemas } from '@0x/json-schemas';
-import { eip712Utils } from '@0x/order-utils';
+import { transactionHashUtils } from '@0x/order-utils';
 import { Order, SignedOrder } from '@0x/types';
-import { BigNumber, signTypedDataUtils } from '@0x/utils';
+import { BigNumber } from '@0x/utils';
 import _ = require('lodash');
 
 import { assert } from './assert';
@@ -19,23 +19,22 @@ export class TransactionEncoder {
         this._exchangeInstance = exchangeInstance;
     }
     /**
-     * Encodes the transaction data for use with the Exchange contract.
+     * Hashes the transaction data for use with the Exchange contract.
      * @param data The ABI Encoded 0x Exchange method. I.e fillOrder
      * @param salt A random value to provide uniqueness and prevent replay attacks.
      * @param signerAddress The address which will sign this transaction.
-     * @return An unsigned hex encoded transaction for use in 0x Exchange executeTransaction.
+     * @return The hash of the 0x transaction.
      */
-    public getTransactionHex(data: string, salt: BigNumber, signerAddress: string): string {
+    public getTransactionHashHex(data: string, salt: BigNumber, signerAddress: string): string {
         const exchangeAddress = this._getExchangeContract().address;
-        const executeTransactionData = {
+        const transaction = {
+            verifyingContractAddress: exchangeAddress,
             salt,
             signerAddress,
             data,
         };
-        const typedData = eip712Utils.createZeroExTransactionTypedData(executeTransactionData, exchangeAddress);
-        const eip712MessageBuffer = signTypedDataUtils.generateTypedDataHash(typedData);
-        const messageHex = `0x${eip712MessageBuffer.toString('hex')}`;
-        return messageHex;
+        const hashHex = transactionHashUtils.getTransactionHashHex(transaction);
+        return hashHex;
     }
     /**
      * Encodes a fillOrder transaction.
diff --git a/packages/contract-wrappers/test/transaction_encoder_test.ts b/packages/contract-wrappers/test/transaction_encoder_test.ts
index ef9eb2cf3..a996b9f08 100644
--- a/packages/contract-wrappers/test/transaction_encoder_test.ts
+++ b/packages/contract-wrappers/test/transaction_encoder_test.ts
@@ -83,8 +83,8 @@ describe('TransactionEncoder', () => {
             signerAddress: string = takerAddress,
         ): Promise<void> => {
             const salt = generatePseudoRandomSalt();
-            const encodedTransaction = encoder.getTransactionHex(data, salt, signerAddress);
-            const signature = await signatureUtils.ecSignHashAsync(provider, encodedTransaction, signerAddress);
+            const transactionHash = encoder.getTransactionHashHex(data, salt, signerAddress);
+            const signature = await signatureUtils.ecSignHashAsync(provider, transactionHash, signerAddress);
             txHash = await contractWrappers.exchange.executeTransactionAsync(
                 salt,
                 signerAddress,
diff --git a/packages/json-schemas/CHANGELOG.json b/packages/json-schemas/CHANGELOG.json
index 869f8bdf1..e174975d1 100644
--- a/packages/json-schemas/CHANGELOG.json
+++ b/packages/json-schemas/CHANGELOG.json
@@ -5,6 +5,10 @@
             {
                 "note": "Upgrade the bignumber.js to v8.0.2",
                 "pr": 1517
+            },
+            {
+                "note": "Add `verifyingContractAddress` to `zeroExTransactionSchema`",
+                "pr": 1576
             }
         ],
         "timestamp": 1549373905
diff --git a/packages/json-schemas/schemas/zero_ex_transaction_schema.json b/packages/json-schemas/schemas/zero_ex_transaction_schema.json
index 0c714f14d..ffdf1f229 100644
--- a/packages/json-schemas/schemas/zero_ex_transaction_schema.json
+++ b/packages/json-schemas/schemas/zero_ex_transaction_schema.json
@@ -1,10 +1,11 @@
 {
     "id": "/zeroExTransactionSchema",
     "properties": {
+        "verifyingContractAddress": { "$ref": "/addressSchema" },
         "data": { "$ref": "/hexSchema" },
         "signerAddress": { "$ref": "/addressSchema" },
         "salt": { "$ref": "/wholeNumberSchema" }
     },
-    "required": ["data", "salt", "signerAddress"],
+    "required": ["verifyingContractAddress", "data", "salt", "signerAddress"],
     "type": "object"
 }
diff --git a/packages/order-utils/CHANGELOG.json b/packages/order-utils/CHANGELOG.json
index 5169208c9..b13ce197a 100644
--- a/packages/order-utils/CHANGELOG.json
+++ b/packages/order-utils/CHANGELOG.json
@@ -1,5 +1,22 @@
 [
     {
+        "version": "5.0.0",
+        "changes": [
+            {
+                "note": "Add `transactionHashUtils`",
+                "pr": 1576
+            },
+            {
+                "note": "Refactor `eip712Utils` to allow custom domain params",
+                "pr": 1576
+            },
+            {
+                "note": "Export constant EIP712 params",
+                "pr": 1576
+            }
+        ]
+    },
+    {
         "version": "4.0.0",
         "changes": [
             {
diff --git a/packages/order-utils/src/constants.ts b/packages/order-utils/src/constants.ts
index a9a687719..3c93575b3 100644
--- a/packages/order-utils/src/constants.ts
+++ b/packages/order-utils/src/constants.ts
@@ -68,9 +68,9 @@ export const constants = {
     SELECTOR_CHAR_LENGTH_WITH_PREFIX: 10,
     INFINITE_TIMESTAMP_SEC: new BigNumber(2524604400), // Close to infinite
     ZERO_AMOUNT: new BigNumber(0),
-    EIP712_DOMAIN_NAME: '0x Protocol',
-    EIP712_DOMAIN_VERSION: '2',
-    EIP712_DOMAIN_SCHEMA: {
+    EXCHANGE_DOMAIN_NAME: '0x Protocol',
+    EXCHANGE_DOMAIN_VERSION: '2',
+    DEFAULT_DOMAIN_SCHEMA: {
         name: 'EIP712Domain',
         parameters: [
             { name: 'name', type: 'string' },
@@ -78,7 +78,7 @@ export const constants = {
             { name: 'verifyingContract', type: 'address' },
         ],
     },
-    EIP712_ORDER_SCHEMA: {
+    EXCHANGE_ORDER_SCHEMA: {
         name: 'Order',
         parameters: [
             { name: 'makerAddress', type: 'address' },
@@ -95,7 +95,7 @@ export const constants = {
             { name: 'takerAssetData', type: 'bytes' },
         ],
     },
-    EIP712_ZEROEX_TRANSACTION_SCHEMA: {
+    EXCHANGE_ZEROEX_TRANSACTION_SCHEMA: {
         name: 'ZeroExTransaction',
         parameters: [
             { name: 'salt', type: 'uint256' },
diff --git a/packages/order-utils/src/eip712_utils.ts b/packages/order-utils/src/eip712_utils.ts
index 385fda989..313653c63 100644
--- a/packages/order-utils/src/eip712_utils.ts
+++ b/packages/order-utils/src/eip712_utils.ts
@@ -1,36 +1,49 @@
 import { assert } from '@0x/assert';
 import { schemas } from '@0x/json-schemas';
-import { EIP712Object, EIP712TypedData, EIP712Types, Order, ZeroExTransaction } from '@0x/types';
+import {
+    EIP712DomainWithDefaultSchema,
+    EIP712Object,
+    EIP712TypedData,
+    EIP712Types,
+    Order,
+    ZeroExTransaction,
+} from '@0x/types';
 import * as _ from 'lodash';
 
 import { constants } from './constants';
 
+export const DEFAULT_DOMAIN_SCHEMA = constants.DEFAULT_DOMAIN_SCHEMA;
+export const EXCHANGE_DOMAIN_NAME = constants.EXCHANGE_DOMAIN_NAME;
+export const EXCHANGE_DOMAIN_VERSION = constants.EXCHANGE_DOMAIN_VERSION;
+export const EXCHANGE_ORDER_SCHEMA = constants.EXCHANGE_ORDER_SCHEMA;
+export const EXCHANGE_ZEROEX_TRANSACTION_SCHEMA = constants.EXCHANGE_ZEROEX_TRANSACTION_SCHEMA;
+
 export const eip712Utils = {
     /**
      * Creates a EIP712TypedData object specific to the 0x protocol for use with signTypedData.
      * @param   primaryType The primary type found in message
      * @param   types The additional types for the data in message
      * @param   message The contents of the message
-     * @param   exchangeAddress The address of the exchange contract
+     * @param   domain Domain containing a name (optional), version (optional), and verifying contract address
      * @return  A typed data object
      */
     createTypedData: (
         primaryType: string,
         types: EIP712Types,
         message: EIP712Object,
-        exchangeAddress: string,
+        domain: EIP712DomainWithDefaultSchema,
     ): EIP712TypedData => {
-        assert.isETHAddressHex('exchangeAddress', exchangeAddress);
+        assert.isETHAddressHex('verifyingContractAddress', domain.verifyingContractAddress);
         assert.isString('primaryType', primaryType);
         const typedData = {
             types: {
-                EIP712Domain: constants.EIP712_DOMAIN_SCHEMA.parameters,
+                EIP712Domain: DEFAULT_DOMAIN_SCHEMA.parameters,
                 ...types,
             },
             domain: {
-                name: constants.EIP712_DOMAIN_NAME,
-                version: constants.EIP712_DOMAIN_VERSION,
-                verifyingContract: exchangeAddress,
+                name: _.isUndefined(domain.name) ? EXCHANGE_DOMAIN_NAME : domain.name,
+                version: _.isUndefined(domain.version) ? EXCHANGE_DOMAIN_VERSION : domain.version,
+                verifyingContract: domain.verifyingContractAddress,
             },
             message,
             primaryType,
@@ -48,11 +61,14 @@ export const eip712Utils = {
         const normalizedOrder = _.mapValues(order, value => {
             return !_.isString(value) ? value.toString() : value;
         });
+        const domain = {
+            verifyingContractAddress: order.exchangeAddress,
+        };
         const typedData = eip712Utils.createTypedData(
-            constants.EIP712_ORDER_SCHEMA.name,
-            { Order: constants.EIP712_ORDER_SCHEMA.parameters },
+            EXCHANGE_ORDER_SCHEMA.name,
+            { Order: EXCHANGE_ORDER_SCHEMA.parameters },
             normalizedOrder,
-            order.exchangeAddress,
+            domain,
         );
         return typedData;
     },
@@ -60,23 +76,22 @@ export const eip712Utils = {
      * Creates an ExecuteTransaction EIP712TypedData object for use with signTypedData and
      * 0x Exchange executeTransaction.
      * @param   ZeroExTransaction the 0x transaction
-     * @param   exchangeAddress The address of the exchange contract
      * @return  A typed data object
      */
-    createZeroExTransactionTypedData: (
-        zeroExTransaction: ZeroExTransaction,
-        exchangeAddress: string,
-    ): EIP712TypedData => {
-        assert.isETHAddressHex('exchangeAddress', exchangeAddress);
+    createZeroExTransactionTypedData: (zeroExTransaction: ZeroExTransaction): EIP712TypedData => {
+        assert.isETHAddressHex('verifyingContractAddress', zeroExTransaction.verifyingContractAddress);
         assert.doesConformToSchema('zeroExTransaction', zeroExTransaction, schemas.zeroExTransactionSchema);
         const normalizedTransaction = _.mapValues(zeroExTransaction, value => {
             return !_.isString(value) ? value.toString() : value;
         });
+        const domain = {
+            verifyingContractAddress: zeroExTransaction.verifyingContractAddress,
+        };
         const typedData = eip712Utils.createTypedData(
-            constants.EIP712_ZEROEX_TRANSACTION_SCHEMA.name,
-            { ZeroExTransaction: constants.EIP712_ZEROEX_TRANSACTION_SCHEMA.parameters },
+            EXCHANGE_ZEROEX_TRANSACTION_SCHEMA.name,
+            { ZeroExTransaction: EXCHANGE_ZEROEX_TRANSACTION_SCHEMA.parameters },
             normalizedTransaction,
-            exchangeAddress,
+            domain,
         );
         return typedData;
     },
diff --git a/packages/order-utils/src/index.ts b/packages/order-utils/src/index.ts
index 2150a02e4..436677efc 100644
--- a/packages/order-utils/src/index.ts
+++ b/packages/order-utils/src/index.ts
@@ -3,6 +3,7 @@ export { signatureUtils } from './signature_utils';
 export { generatePseudoRandomSalt } from './salt';
 export { assetDataUtils } from './asset_data_utils';
 export { marketUtils } from './market_utils';
+export { transactionHashUtils } from './transaction_hash';
 export { rateUtils } from './rate_utils';
 export { sortingUtils } from './sorting_utils';
 export { orderParsingUtils } from './parsing_utils';
@@ -18,7 +19,14 @@ export { ExchangeTransferSimulator } from './exchange_transfer_simulator';
 export { BalanceAndProxyAllowanceLazyStore } from './store/balance_and_proxy_allowance_lazy_store';
 export { OrderFilledCancelledLazyStore } from './store/order_filled_cancelled_lazy_store';
 
-export { eip712Utils } from './eip712_utils';
+export {
+    eip712Utils,
+    DEFAULT_DOMAIN_SCHEMA,
+    EXCHANGE_DOMAIN_NAME,
+    EXCHANGE_DOMAIN_VERSION,
+    EXCHANGE_ORDER_SCHEMA,
+    EXCHANGE_ZEROEX_TRANSACTION_SCHEMA,
+} from './eip712_utils';
 
 export {
     Provider,
@@ -50,7 +58,9 @@ export {
     EIP712Types,
     EIP712Object,
     EIP712ObjectValue,
+    EIP712DomainWithDefaultSchema,
     ZeroExTransaction,
+    SignedZeroExTransaction,
 } from '@0x/types';
 export {
     OrderError,
diff --git a/packages/order-utils/src/order_hash.ts b/packages/order-utils/src/order_hash.ts
index c8e9be71e..ce7e6d85f 100644
--- a/packages/order-utils/src/order_hash.ts
+++ b/packages/order-utils/src/order_hash.ts
@@ -4,6 +4,7 @@ import { signTypedDataUtils } from '@0x/utils';
 import * as _ from 'lodash';
 
 import { assert } from './assert';
+import { constants } from './constants';
 import { eip712Utils } from './eip712_utils';
 
 const INVALID_TAKER_FORMAT = 'instance.takerAddress is not of a type(s) string';
@@ -34,8 +35,9 @@ export const orderHashUtils = {
             assert.doesConformToSchema('order', order, schemas.orderSchema, [schemas.hexSchema]);
         } catch (error) {
             if (_.includes(error.message, INVALID_TAKER_FORMAT)) {
-                const errMsg =
-                    'Order taker must be of type string. If you want anyone to be able to fill an order - pass ZeroEx.NULL_ADDRESS';
+                const errMsg = `Order taker must be of type string. If you want anyone to be able to fill an order - pass ${
+                    constants.NULL_ADDRESS
+                }`;
                 throw new Error(errMsg);
             }
             throw error;
@@ -51,6 +53,17 @@ export const orderHashUtils = {
      * @return  A Buffer containing the resulting orderHash from hashing the supplied order
      */
     getOrderHashBuffer(order: SignedOrder | Order): Buffer {
+        try {
+            assert.doesConformToSchema('order', order, schemas.orderSchema, [schemas.hexSchema]);
+        } catch (error) {
+            if (_.includes(error.message, INVALID_TAKER_FORMAT)) {
+                const errMsg = `Order taker must be of type string. If you want anyone to be able to fill an order - pass ${
+                    constants.NULL_ADDRESS
+                }`;
+                throw new Error(errMsg);
+            }
+            throw error;
+        }
         const typedData = eip712Utils.createOrderTypedData(order);
         const orderHashBuff = signTypedDataUtils.generateTypedDataHash(typedData);
         return orderHashBuff;
diff --git a/packages/order-utils/src/transaction_hash.ts b/packages/order-utils/src/transaction_hash.ts
new file mode 100644
index 000000000..2b2345af7
--- /dev/null
+++ b/packages/order-utils/src/transaction_hash.ts
@@ -0,0 +1,46 @@
+import { schemas, SchemaValidator } from '@0x/json-schemas';
+import { SignedZeroExTransaction, ZeroExTransaction } from '@0x/types';
+import { signTypedDataUtils } from '@0x/utils';
+import * as _ from 'lodash';
+
+import { assert } from './assert';
+import { eip712Utils } from './eip712_utils';
+
+export const transactionHashUtils = {
+    /**
+     * Checks if the supplied hex encoded 0x transaction hash is valid.
+     * Note: Valid means it has the expected format, not that a transaction with the transactionHash exists.
+     * Use this method when processing transactionHashes submitted as user input.
+     * @param   transactionHash    Hex encoded transactionHash.
+     * @return  Whether the supplied transactionHash has the expected format.
+     */
+    isValidTransactionHash(transactionHash: string): boolean {
+        // Since this method can be called to check if any arbitrary string conforms to an transactionHash's
+        // format, we only assert that we were indeed passed a string.
+        assert.isString('transactionHash', transactionHash);
+        const schemaValidator = new SchemaValidator();
+        const isValid = schemaValidator.validate(transactionHash, schemas.orderHashSchema).valid;
+        return isValid;
+    },
+    /**
+     * Computes the transactionHash for a supplied 0x transaction.
+     * @param   transaction   An object that conforms to the ZeroExTransaction or SignedZeroExTransaction interface definitions.
+     * @return  Hex encoded string transactionHash from hashing the supplied order.
+     */
+    getTransactionHashHex(transaction: ZeroExTransaction | SignedZeroExTransaction): string {
+        assert.doesConformToSchema('transaction', transaction, schemas.zeroExTransactionSchema, [schemas.hexSchema]);
+        const transactionHashBuff = transactionHashUtils.getTransactionHashBuffer(transaction);
+        const transactionHashHex = `0x${transactionHashBuff.toString('hex')}`;
+        return transactionHashHex;
+    },
+    /**
+     * Computes the transactionHash for a supplied 0x transaction.
+     * @param   transaction   An object that conforms to the ZeroExTransaction or SignedZeroExTransaction interface definitions.
+     * @return  A Buffer containing the resulting transactionHash from hashing the supplied 0x transaction.
+     */
+    getTransactionHashBuffer(transaction: ZeroExTransaction | SignedZeroExTransaction): Buffer {
+        const typedData = eip712Utils.createZeroExTransactionTypedData(transaction);
+        const transactionHashBuff = signTypedDataUtils.generateTypedDataHash(typedData);
+        return transactionHashBuff;
+    },
+};
diff --git a/packages/order-utils/test/eip712_utils_test.ts b/packages/order-utils/test/eip712_utils_test.ts
index a54e49958..4208e9beb 100644
--- a/packages/order-utils/test/eip712_utils_test.ts
+++ b/packages/order-utils/test/eip712_utils_test.ts
@@ -3,7 +3,12 @@ import * as chai from 'chai';
 import 'mocha';
 
 import { constants } from '../src/constants';
-import { eip712Utils } from '../src/eip712_utils';
+import {
+    eip712Utils,
+    EXCHANGE_DOMAIN_NAME,
+    EXCHANGE_DOMAIN_VERSION,
+    EXCHANGE_ZEROEX_TRANSACTION_SCHEMA,
+} from '../src/eip712_utils';
 
 import { chaiSetup } from './utils/chai_setup';
 
@@ -12,33 +17,55 @@ const expect = chai.expect;
 
 describe('EIP712 Utils', () => {
     describe('createTypedData', () => {
-        it('adds in the EIP712DomainSeparator', () => {
+        it('adds in the EIP712DomainSeparator with default values', () => {
             const primaryType = 'Test';
             const typedData = eip712Utils.createTypedData(
                 primaryType,
                 { Test: [{ name: 'testValue', type: 'uint256' }] },
                 { testValue: '1' },
-                constants.NULL_ADDRESS,
+                { verifyingContractAddress: constants.NULL_ADDRESS },
             );
             expect(typedData.domain).to.not.be.undefined();
             expect(typedData.types.EIP712Domain).to.not.be.undefined();
             const domainObject = typedData.domain;
-            expect(domainObject.name).to.eq(constants.EIP712_DOMAIN_NAME);
+            expect(domainObject.name).to.eq(EXCHANGE_DOMAIN_NAME);
+            expect(domainObject.version).to.eq(EXCHANGE_DOMAIN_VERSION);
+            expect(domainObject.verifyingContract).to.eq(constants.NULL_ADDRESS);
+            expect(typedData.primaryType).to.eq(primaryType);
+        });
+        it('adds in the EIP712DomainSeparator without default values', () => {
+            const primaryType = 'Test';
+            const domainName = 'testDomain';
+            const domainVersion = 'testVersion';
+            const typedData = eip712Utils.createTypedData(
+                primaryType,
+                { Test: [{ name: 'testValue', type: 'uint256' }] },
+                { testValue: '1' },
+                { name: domainName, version: domainVersion, verifyingContractAddress: constants.NULL_ADDRESS },
+            );
+            expect(typedData.domain).to.not.be.undefined();
+            expect(typedData.types.EIP712Domain).to.not.be.undefined();
+            const domainObject = typedData.domain;
+            expect(domainObject.name).to.eq(domainName);
+            expect(domainObject.version).to.eq(domainVersion);
+            expect(domainObject.verifyingContract).to.eq(constants.NULL_ADDRESS);
             expect(typedData.primaryType).to.eq(primaryType);
         });
     });
-    describe('createTypedData', () => {
+    describe('createZeroExTransactionTypedData', () => {
         it('adds in the EIP712DomainSeparator', () => {
-            const typedData = eip712Utils.createZeroExTransactionTypedData(
-                {
-                    salt: new BigNumber('0'),
-                    data: constants.NULL_BYTES,
-                    signerAddress: constants.NULL_ADDRESS,
-                },
-                constants.NULL_ADDRESS,
-            );
-            expect(typedData.primaryType).to.eq(constants.EIP712_ZEROEX_TRANSACTION_SCHEMA.name);
+            const typedData = eip712Utils.createZeroExTransactionTypedData({
+                salt: new BigNumber('0'),
+                data: constants.NULL_BYTES,
+                signerAddress: constants.NULL_ADDRESS,
+                verifyingContractAddress: constants.NULL_ADDRESS,
+            });
+            expect(typedData.primaryType).to.eq(EXCHANGE_ZEROEX_TRANSACTION_SCHEMA.name);
             expect(typedData.types.EIP712Domain).to.not.be.undefined();
+            const domainObject = typedData.domain;
+            expect(domainObject.name).to.eq(EXCHANGE_DOMAIN_NAME);
+            expect(domainObject.version).to.eq(EXCHANGE_DOMAIN_VERSION);
+            expect(domainObject.verifyingContract).to.eq(constants.NULL_ADDRESS);
         });
     });
 });
diff --git a/packages/order-utils/test/order_hash_test.ts b/packages/order-utils/test/order_hash_test.ts
index 30fb15a37..514fc2709 100644
--- a/packages/order-utils/test/order_hash_test.ts
+++ b/packages/order-utils/test/order_hash_test.ts
@@ -54,8 +54,9 @@ describe('Order hashing', () => {
                 ...order,
                 takerAddress: (null as any) as string,
             };
-            const expectedErrorMessage =
-                'Order taker must be of type string. If you want anyone to be able to fill an order - pass ZeroEx.NULL_ADDRESS';
+            const expectedErrorMessage = `Order taker must be of type string. If you want anyone to be able to fill an order - pass ${
+                constants.NULL_ADDRESS
+            }`;
             expect(() => orderHashUtils.getOrderHashHex(orderWithInvalidtakerFormat)).to.throw(expectedErrorMessage);
         });
     });
diff --git a/packages/order-utils/test/transaction_hash_test.ts b/packages/order-utils/test/transaction_hash_test.ts
new file mode 100644
index 000000000..c7ca33a64
--- /dev/null
+++ b/packages/order-utils/test/transaction_hash_test.ts
@@ -0,0 +1,56 @@
+import { ZeroExTransaction } from '@0x/types';
+import { BigNumber } from '@0x/utils';
+import * as chai from 'chai';
+import 'mocha';
+
+import { transactionHashUtils } from '../src';
+
+import { constants } from '../src/constants';
+
+import { chaiSetup } from './utils/chai_setup';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('0x transaction hashing', () => {
+    describe('#getTransactionHashHex', () => {
+        const expectedTransactionHash = '0x82c9bb2dcac4f868ec7a15c20ff6175cfc384c20ae6a872aa0342a840f108c2b';
+        const fakeVerifyingContractAddress = '0x5e72914535f202659083db3a02c984188fa26e9f';
+        const transaction: ZeroExTransaction = {
+            verifyingContractAddress: fakeVerifyingContractAddress,
+            signerAddress: constants.NULL_ADDRESS,
+            salt: new BigNumber(0),
+            data: constants.NULL_BYTES,
+        };
+        it('calculates the transaction hash', async () => {
+            const transactionHash = transactionHashUtils.getTransactionHashHex(transaction);
+            expect(transactionHash).to.be.equal(expectedTransactionHash);
+        });
+        it('calculates the transaction hash if amounts are strings', async () => {
+            // It's common for developers using javascript to provide the amounts
+            // as strings. Since we eventually toString() the BigNumber
+            // before encoding we should result in the same orderHash in this scenario
+            // tslint:disable-next-line:no-unnecessary-type-assertion
+            const transactionHash = transactionHashUtils.getTransactionHashHex({
+                ...transaction,
+                salt: '0',
+            } as any);
+            expect(transactionHash).to.be.equal(expectedTransactionHash);
+        });
+    });
+    describe('#isValidTransactionHash', () => {
+        it('returns false if the value is not a hex string', () => {
+            const isValid = transactionHashUtils.isValidTransactionHash('not a hex');
+            expect(isValid).to.be.false();
+        });
+        it('returns false if the length is wrong', () => {
+            const isValid = transactionHashUtils.isValidTransactionHash('0xdeadbeef');
+            expect(isValid).to.be.false();
+        });
+        it('returns true if order hash is correct', () => {
+            const orderHashLength = 65;
+            const isValid = transactionHashUtils.isValidTransactionHash(`0x${Array(orderHashLength).join('0')}`);
+            expect(isValid).to.be.true();
+        });
+    });
+});
diff --git a/packages/types/CHANGELOG.json b/packages/types/CHANGELOG.json
index b9ddb5acf..c2a54f824 100644
--- a/packages/types/CHANGELOG.json
+++ b/packages/types/CHANGELOG.json
@@ -5,6 +5,14 @@
             {
                 "note": "Upgrade the bignumber.js to v8.0.2",
                 "pr": 1517
+            },
+            {
+                "note": "Update `ZeroExTransaction` type and add `SignedZeroExTransaction` type",
+                "pr": 1576
+            },
+            {
+                "note": "Add `EIP712DomainWithDefaultSchema` type",
+                "pr": 1576
             }
         ],
         "timestamp": 1549373905
diff --git a/packages/types/src/index.ts b/packages/types/src/index.ts
index 49f788fb0..a30a0494f 100644
--- a/packages/types/src/index.ts
+++ b/packages/types/src/index.ts
@@ -45,11 +45,16 @@ export interface SignedOrder extends Order {
  * ZeroExTransaction for use with 0x Exchange executeTransaction
  */
 export interface ZeroExTransaction {
+    verifyingContractAddress: string;
     salt: BigNumber;
     signerAddress: string;
     data: string;
 }
 
+export interface SignedZeroExTransaction extends ZeroExTransaction {
+    signature: string;
+}
+
 /**
  * Elliptic Curve signature
  */
@@ -685,3 +690,9 @@ export interface DutchAuctionDetails {
     currentAmount: BigNumber;
     currentTimeSeconds: BigNumber;
 }
+
+export interface EIP712DomainWithDefaultSchema {
+    name?: string;
+    version?: string;
+    verifyingContractAddress: string;
+}
diff --git a/python-packages/json_schemas/src/zero_ex/json_schemas/schemas/zero_ex_transaction_schema.json b/python-packages/json_schemas/src/zero_ex/json_schemas/schemas/zero_ex_transaction_schema.json
index 0c714f14d..ffdf1f229 100644
--- a/python-packages/json_schemas/src/zero_ex/json_schemas/schemas/zero_ex_transaction_schema.json
+++ b/python-packages/json_schemas/src/zero_ex/json_schemas/schemas/zero_ex_transaction_schema.json
@@ -1,10 +1,11 @@
 {
     "id": "/zeroExTransactionSchema",
     "properties": {
+        "verifyingContractAddress": { "$ref": "/addressSchema" },
         "data": { "$ref": "/hexSchema" },
         "signerAddress": { "$ref": "/addressSchema" },
         "salt": { "$ref": "/wholeNumberSchema" }
     },
-    "required": ["data", "salt", "signerAddress"],
+    "required": ["verifyingContractAddress", "data", "salt", "signerAddress"],
     "type": "object"
 }