1 files changed, 22 insertions, 5 deletions
diff --git a/packages/contracts/src/utils/transaction_factory.ts b/packages/contracts/src/utils/transaction_factory.ts
index a060263b1..19ef4e1bf 100644
--- a/packages/contracts/src/utils/transaction_factory.ts
+++ b/packages/contracts/src/utils/transaction_factory.ts
@@ -1,10 +1,19 @@
-import { crypto, generatePseudoRandomSalt } from '@0xproject/order-utils';
+import { EIP712Schema, EIP712Types, EIP712Utils, generatePseudoRandomSalt } from '@0xproject/order-utils';
 import { SignatureType } from '@0xproject/types';
 import * as ethUtil from 'ethereumjs-util';
 
 import { signingUtils } from './signing_utils';
 import { SignedTransaction } from './types';
 
+const EIP712_ZEROEX_TRANSACTION_SCHEMA: EIP712Schema = {
+    name: 'ZeroExTransaction',
+    parameters: [
+        { name: 'salt', type: EIP712Types.Uint256 },
+        { name: 'signer', type: EIP712Types.Address },
+        { name: 'data', type: EIP712Types.Bytes },
+    ],
+};
+
 export class TransactionFactory {
     private _signerBuff: Buffer;
     private _exchangeAddress: string;
@@ -16,14 +25,22 @@ export class TransactionFactory {
     }
     public newSignedTransaction(data: string, signatureType: SignatureType = SignatureType.EthSign): SignedTransaction {
         const salt = generatePseudoRandomSalt();
-        const txHash = crypto.solSHA3([this._exchangeAddress, this._signerBuff, salt, ethUtil.toBuffer(data)]);
+        const signer = `0x${this._signerBuff.toString('hex')}`;
+        const executeTransactionData = {
+            salt,
+            signer,
+            data,
+        };
+        const executeTransactionHashBuff = EIP712Utils.structHash(
+            EIP712_ZEROEX_TRANSACTION_SCHEMA,
+            executeTransactionData,
+        );
+        const txHash = EIP712Utils.createEIP712Message(executeTransactionHashBuff, this._exchangeAddress);
         const signature = signingUtils.signMessage(txHash, this._privateKey, signatureType);
         const signedTx = {
             exchangeAddress: this._exchangeAddress,
-            salt,
-            signer: `0x${this._signerBuff.toString('hex')}`,
-            data,
             signature: `0x${signature.toString('hex')}`,
+            ...executeTransactionData,
         };
         return signedTx;
     }