Add offset to signature

1 files changed, 13 insertions, 11 deletions

diff --git a/packages/contracts/src/contracts/current/protocol/Exchange/MixinWrapperFunctions.sol b/packages/contracts/src/contracts/current/protocol/Exchange/MixinWrapperFunctions.sol
index db8a4bfad..a2a168656 100644
--- a/packages/contracts/src/contracts/current/protocol/Exchange/MixinWrapperFunctions.sol
+++ b/packages/contracts/src/contracts/current/protocol/Exchange/MixinWrapperFunctions.sol
@@ -63,7 +63,7 @@ contract MixinWrapperFunctions is
     {
         // We need to call MExchangeCore.fillOrder using a delegatecall in
         // assembly so that we can intercept a call that throws. For this, we
-        // need the input encoded in memory in the Ethereum ABI format [1].
+        // need the input encoded in memory in the Ethereum ABIv2 format [1].
         //
         // | Offset | Length | Contents                     |
         // |--------|--------|------------------------------|
@@ -71,22 +71,23 @@ contract MixinWrapperFunctions is
         // | 4      | 160    | address[5] orderAddresses    |
         // | 164    | 192    | uint256[6] orderValues       |
         // | 356    | 32     | uint256 takerTokenFillAmount |
-        // | 388    | 32     | len(signature)               |
-        // | 420    | (1)    | signature                    |
+        // | 388    | 32     | offset to signature (416)    |
+        // | 420    | 32     | len(signature)               |
+        // | 452    | (1)    | signature                    |
         // | (2)    | (3)    | padding (zero)               |
         // | (4)    |        | end of input                 |
         //
         // (1): len(signature)
-        // (2): 420 + len(signature)
+        // (2): 452 + len(signature)
         // (3): (32 - len(signature)) mod 32
-        // (4): 420 + len(signature) + (32 - len(signature)) mod 32
+        // (4): 452 + len(signature) + (32 - len(signature)) mod 32
         //
         // [1]: https://solidity.readthedocs.io/en/develop/abi-spec.html
         
         // Allocate memory for input
         uint256 signatureLength = signature.length;
         uint256 paddingLength = (32 - signatureLength) % 32
-        uint256 inputSize = 420 + signatureLength + paddingLength;
+        uint256 inputSize = 452 + signatureLength + paddingLength;
         bytes memory input = new bytes(inputSize);
         
         // The in memory layout of `bytes memory input` starts with
@@ -108,8 +109,8 @@ contract MixinWrapperFunctions is
             mstore(start, FILL_ORDER_FUNCTION_SIGNATURE);
         }
         
-        // Write orderAddresses, orderValues, takerTokenFillAmount
-        // and len(signature)
+        // Write orderAddresses, orderValues, takerTokenFillAmount,
+        // offset to signature and len(signature)
         // It is done in assembly so we can write 32 bytes at a time. In
         // solidity we would have to copy one byte at a time.
         // Fixed size arrays do not have the `uint256 length` prefix that
@@ -126,15 +127,16 @@ contract MixinWrapperFunctions is
             mstore(add(start, 260), add(orderValues, 96))   // takerFee
             mstore(add(start, 292), add(orderValues, 128))  // expiration
             mstore(add(start, 356), takerTokenFillAmount)
-            mstore(add(start, 388), signatureLength)
+            mstore(add(start, 388), 416)
+            mstore(add(start, 420), signatureLength)
         }
         
         // Write signature contents and padding one byte at a time
         for (uint256 i = 0; i < signatureLength; i++) {
-            input[420 + i] = signature[i];
+            input[452 + i] = signature[i];
         }
         for (uint256 i = 0; i < paddingLength; i++) {
-            input[420 + signatureLength + i] = 0x00;
+            input[452 + signatureLength + i] = 0x00;
         }
         
         // Call the function