Merge branch 'v2-prototype' into refactor/order-utils/for-v2

* v2-prototype: (45 commits)
  Check length before accessing indices, add awaitTransactionSuccess where needed, and rename function
  Add back before/after snapshots for each test
  Rename Signer to Wallet, rename GAS_ESTIMATE to GAS_LIMIT
  Make preSigned and allowedValidators mappings public
  Change names of signature types
  Fix formatting and tests
  Make AssetProxyId last byte of assetData
  Add signer to txHash, allow approveValidator to be used with executeTransaction
  Update Whitelist
  Fix Exchange interface
  Increase block gas limit
  Use last byte of signature as signature type
  Remove TxOrigin signature type, modify whitelist to use Validator signature type
  Update Whitelist contract with comments, also require maker to be whitelisted
  Fix build
  Add example whitelist contract and minimum tests
  Add sample whitelist contract
  Add TxOrigin signature type and rearrange order of types
  Add approveValidator function
  Add Validator signature type
  ...

# Conflicts:
#	packages/contracts/src/contracts/current/protocol/Exchange/MixinSignatureValidator.sol
#	packages/contracts/src/utils/types.ts
#	packages/contracts/test/exchange/transactions.ts
#	packages/order-utils/src/asset_proxy_utils.ts

2 files changed, 31 insertions, 30 deletions

diff --git a/packages/order-utils/src/asset_proxy_utils.ts b/packages/order-utils/src/asset_proxy_utils.ts
index 11f81c656..5a084deba 100644
--- a/packages/order-utils/src/asset_proxy_utils.ts
+++ b/packages/order-utils/src/asset_proxy_utils.ts
@@ -3,8 +3,8 @@ import { BigNumber } from '@0xproject/utils';
 import BN = require('bn.js');
 import ethUtil = require('ethereumjs-util');
 
-const ERC20_PROXY_METADATA_BYTE_LENGTH = 21;
-const ERC721_PROXY_METADATA_BYTE_LENGTH = 53;
+const ERC20_PROXY_METADATA_BYTE_LENGTH = 20;
+const ERC721_PROXY_METADATA_BYTE_LENGTH = 52;
 
 export const assetProxyUtils = {
     encodeAssetProxyId(assetProxyId: AssetProxyId): Buffer {
@@ -43,7 +43,7 @@ export const assetProxyUtils = {
     encodeERC20ProxyData(tokenAddress: string): string {
         const encodedAssetProxyId = assetProxyUtils.encodeAssetProxyId(AssetProxyId.ERC20);
         const encodedAddress = assetProxyUtils.encodeAddress(tokenAddress);
-        const encodedMetadata = Buffer.concat([encodedAssetProxyId, encodedAddress]);
+        const encodedMetadata = Buffer.concat([encodedAddress, encodedAssetProxyId]);
         const encodedMetadataHex = ethUtil.bufferToHex(encodedMetadata);
         return encodedMetadataHex;
     },
@@ -56,7 +56,7 @@ export const assetProxyUtils = {
                 }`,
             );
         }
-        const encodedAssetProxyId = encodedProxyMetadata.slice(0, 1);
+        const encodedAssetProxyId = encodedProxyMetadata.slice(-1);
         const assetProxyId = assetProxyUtils.decodeAssetProxyId(encodedAssetProxyId);
         if (assetProxyId !== AssetProxyId.ERC20) {
             throw new Error(
@@ -65,7 +65,7 @@ export const assetProxyUtils = {
                 }), but got ${assetProxyId}`,
             );
         }
-        const encodedTokenAddress = encodedProxyMetadata.slice(1, ERC20_PROXY_METADATA_BYTE_LENGTH);
+        const encodedTokenAddress = encodedProxyMetadata.slice(0, ERC20_PROXY_METADATA_BYTE_LENGTH);
         const tokenAddress = assetProxyUtils.decodeAddress(encodedTokenAddress);
         const erc20ProxyData = {
             assetProxyId,
@@ -77,7 +77,7 @@ export const assetProxyUtils = {
         const encodedAssetProxyId = assetProxyUtils.encodeAssetProxyId(AssetProxyId.ERC721);
         const encodedAddress = assetProxyUtils.encodeAddress(tokenAddress);
         const encodedTokenId = assetProxyUtils.encodeUint256(tokenId);
-        const encodedMetadata = Buffer.concat([encodedAssetProxyId, encodedAddress, encodedTokenId]);
+        const encodedMetadata = Buffer.concat([encodedAddress, encodedTokenId, encodedAssetProxyId]);
         const encodedMetadataHex = ethUtil.bufferToHex(encodedMetadata);
         return encodedMetadataHex;
     },
@@ -90,7 +90,7 @@ export const assetProxyUtils = {
                 }`,
             );
         }
-        const encodedAssetProxyId = encodedProxyMetadata.slice(0, 1);
+        const encodedAssetProxyId = encodedProxyMetadata.slice(-1);
         const assetProxyId = assetProxyUtils.decodeAssetProxyId(encodedAssetProxyId);
         if (assetProxyId !== AssetProxyId.ERC721) {
             throw new Error(
@@ -99,8 +99,8 @@ export const assetProxyUtils = {
                 }), but got ${assetProxyId}`,
             );
         }
-        const addressOffset = 21;
-        const encodedTokenAddress = encodedProxyMetadata.slice(1, addressOffset);
+        const addressOffset = 20;
+        const encodedTokenAddress = encodedProxyMetadata.slice(0, addressOffset);
         const tokenAddress = assetProxyUtils.decodeAddress(encodedTokenAddress);
         const encodedTokenId = encodedProxyMetadata.slice(addressOffset, ERC721_PROXY_METADATA_BYTE_LENGTH);
         const tokenId = assetProxyUtils.decodeUint256(encodedTokenId);
@@ -120,7 +120,7 @@ export const assetProxyUtils = {
                 }`,
             );
         }
-        const encodedAssetProxyId = encodedProxyMetadata.slice(0, 1);
+        const encodedAssetProxyId = encodedProxyMetadata.slice(-1);
         const assetProxyId = assetProxyUtils.decodeAssetProxyId(encodedAssetProxyId);
         return assetProxyId;
     },
diff --git a/packages/order-utils/src/signature_utils.ts b/packages/order-utils/src/signature_utils.ts
index f1466973c..8e387a6ae 100644
--- a/packages/order-utils/src/signature_utils.ts
+++ b/packages/order-utils/src/signature_utils.ts
@@ -34,41 +34,40 @@ export async function isValidSignatureAsync(
         case SignatureType.Invalid:
             return false;
 
-        case SignatureType.Caller:
-            // HACK: We currently do not "validate" the caller signature type.
-            // It can only be validated during Exchange contract execution.
-            throw new Error('Caller signature type cannot be validated off-chain');
-
-        // TODO: Rename this type to `EthSign` b/c multiple of the signature
-        // types use ECRecover...
-        case SignatureType.Ecrecover: {
-            const ecSignature = parseECSignature(signature);
-            const prefixedMessageHex = addSignedMessagePrefix(data, MessagePrefixType.EthSign);
-            return isValidECSignature(prefixedMessageHex, ecSignature, signerAddress);
-        }
-
         case SignatureType.EIP712: {
             const ecSignature = parseECSignature(signature);
             return isValidECSignature(data, ecSignature, signerAddress);
         }
 
-        case SignatureType.Trezor: {
-            const prefixedMessageHex = addSignedMessagePrefix(data, MessagePrefixType.Trezor);
+        case SignatureType.EthSign: {
             const ecSignature = parseECSignature(signature);
+            const prefixedMessageHex = addSignedMessagePrefix(data, MessagePrefixType.EthSign);
             return isValidECSignature(prefixedMessageHex, ecSignature, signerAddress);
         }
 
-        // TODO: Rename Contract -> Wallet
-        case SignatureType.Contract: {
+        case SignatureType.Caller:
+            // HACK: We currently do not "validate" the caller signature type.
+            // It can only be validated during Exchange contract execution.
+            throw new Error('Caller signature type cannot be validated off-chain');
+
+        case SignatureType.Wallet: {
             const signerContract = new ISignerContract(artifacts.ISigner.abi, signerAddress, provider);
             const isValid = await signerContract.isValidSignature.callAsync(data, signature);
             return isValid;
         }
 
+        // TODO: Add SignatureType.Validator
+
         case SignatureType.PreSigned: {
             return isValidPresignedSignatureAsync(provider, data, signature, signerAddress);
         }
 
+        case SignatureType.Trezor: {
+            const prefixedMessageHex = addSignedMessagePrefix(data, MessagePrefixType.Trezor);
+            const ecSignature = parseECSignature(signature);
+            return isValidECSignature(prefixedMessageHex, ecSignature, signerAddress);
+        }
+
         default:
             throw new Error(`Unhandled SignatureType: ${signatureTypeIndexIfExists}`);
     }
@@ -205,15 +204,16 @@ function hashTrezorPersonalMessage(message: Buffer): Buffer {
 }
 
 function parseECSignature(signature: string): ECSignature {
+    assert.isHexString('signature', signature);
     const signatureTypeIndexIfExists = getSignatureTypeIndexIfExists(signature);
-    const ecSignatureTypes = [SignatureType.Ecrecover, SignatureType.EIP712, SignatureType.Trezor];
+    const ecSignatureTypes = [SignatureType.EthSign, SignatureType.EIP712, SignatureType.Trezor];
     const isECSignatureType = _.includes(ecSignatureTypes, signatureTypeIndexIfExists);
     if (!isECSignatureType) {
         throw new Error(`Cannot parse non-ECSignature type: ${signatureTypeIndexIfExists}`);
     }
 
     // tslint:disable-next-line:custom-no-magic-numbers
-    const vrsHex = `0x${signature.substr(4)}`;
+    const vrsHex = signature.slice(0, -2);
     const ecSignature = parseSignatureHexAsVRS(vrsHex);
 
     return ecSignature;
@@ -221,7 +221,8 @@ function parseECSignature(signature: string): ECSignature {
 
 function getSignatureTypeIndexIfExists(signature: string): number {
     const unprefixedSignature = ethUtil.stripHexPrefix(signature);
-    const signatureTypeHex = unprefixedSignature.substr(0, 2);
+    // tslint:disable-next-line:custom-no-magic-numbers
+    const signatureTypeHex = unprefixedSignature.slice(-2);
     const base = 16;
     const signatureTypeInt = parseInt(signatureTypeHex, base);
     return signatureTypeInt;