3 files changed, 16 insertions, 4 deletions
diff --git a/src/ts/0x.js.ts b/src/ts/0x.js.ts
index 1cc2d8b44..d189b48b1 100644
--- a/src/ts/0x.js.ts
+++ b/src/ts/0x.js.ts
@@ -13,18 +13,19 @@ export interface ECSignature {
 }
 
 const MAX_DIGITS_IN_UNSIGNED_256_INT = 78;
+const ORDER_HASH_LENGTH = 66;
 
 export class ZeroEx {
     /**
      * Verifies that the elliptic curve signature `signature` was generated
      * by signing `data` with the private key corresponding to the `signer` address.
      */
-    public static isValidSignature(data: string, signature: ECSignature, signer: ETHAddressHex): boolean {
-        assert.isString('data', data);
+    public static isValidSignature(dataHex: string, signature: ECSignature, signer: ETHAddressHex): boolean {
+        assert.isHexString('dataHex', dataHex);
         assert.doesConformToSchema('signature', signature, ECSignatureSchema);
         assert.isETHAddressHex('signer', signer);
 
-        const dataBuff = ethUtil.toBuffer(data);
+        const dataBuff = ethUtil.toBuffer(dataHex);
         const msgHashBuff = ethUtil.hashPersonalMessage(dataBuff);
         try {
             const pubKey = ethUtil.ecrecover(msgHashBuff,
@@ -50,4 +51,9 @@ export class ZeroEx {
         const salt = randomNumber.times(factor).round();
         return salt;
     }
+    /** Checks if order hash is valid */
+    public static isValidOrderHash(orderHash: string): boolean {
+        assert.isHexString('orderHash', orderHash);
+        return orderHash.length === ORDER_HASH_LENGTH;
+    }
 }
diff --git a/src/ts/globals.d.ts b/src/ts/globals.d.ts
index 659638a1e..58efe136a 100644
--- a/src/ts/globals.d.ts
+++ b/src/ts/globals.d.ts
@@ -7,7 +7,7 @@ declare interface Schema {
 }
 
 declare module 'ethereumjs-util' {
-    const toBuffer: (data: string) => Buffer;
+    const toBuffer: (dataHex: string) => Buffer;
     const hashPersonalMessage: (msg: Buffer) => Buffer;
     const bufferToHex: (buff: Buffer) => string;
     const ecrecover: (msgHashBuff: Buffer, v: number, r: Buffer, s: Buffer) => ETHPublicKey;
diff --git a/src/ts/utils/assert.ts b/src/ts/utils/assert.ts
index 972047118..58182dac0 100644
--- a/src/ts/utils/assert.ts
+++ b/src/ts/utils/assert.ts
@@ -3,6 +3,8 @@ import * as BigNumber from 'bignumber.js';
 import Web3 = require('web3');
 import {SchemaValidator} from './schema_validator';
 
+const HEX_REGEX = /^0x([0-9A-F]{2})*$/i;
+
 export const assert = {
     isBigNumber(variableName: string, value: BigNumber.BigNumber) {
         const isBigNumber = _.isObject(value) && value.isBigNumber;
@@ -11,6 +13,10 @@ export const assert = {
     isString(variableName: string, value: string) {
         this.assert(_.isString(value), this.typeAssertionMessage(variableName, 'string', value));
     },
+    isHexString(variableName: string, value: string) {
+        this.assert(_.isString(value) && HEX_REGEX.test(value),
+            this.typeAssertionMessage(variableName, 'HexString', value));
+    },
     isETHAddressHex(variableName: string, value: ETHAddressHex) {
         const web3 = new Web3();
         this.assert(web3.isAddress(value), this.typeAssertionMessage(variableName, 'ETHAddressHex', value));