Omniscia Xcaliswap Audit
Multiswap Code Style Findings
Multiswap Code Style Findings
MPA-01C: Inexistent Error Messages
| Type | Severity | Location |
|---|---|---|
| Code Style |  | Multiswap.sol:L98, L101 |
Description:
The linked require checks have no error messages explicitly defined.
Example:
98require(token.code.length > 0);Recommendation:
We advise each to be set so to increase the legibility of the codebase and aid in validating the require checks' conditions.
Alleviation:
The Xcaliswap team has removed the _safeTransfer function.
MPA-02C: Redundant Consecutive Checks
| Type | Severity | Location |
|---|---|---|
| Gas Optimization | | Multiswap.sol:L42, L54 |
Description:
The linked require checks evaluate that a particular value is greater-than zero and then evaluate that it is greater-than a positive number.
Example:
40if (eth = (_token == address(0))) {41 // Caller wants to multiswap some ETH42 require(msg.value > 0 && msg.value > 10000, "no ETH sent");43 preBalance = address(this).balance;44 for (uint i = 0; i < length; ++i) { 45 uint amount_ = msg.value * _weights[i] / 10000;46 (bool success, bytes memory data) = router.call{value: amount_}(_swapData[i]);47 if (!success) revert ErrorSwapping(i);48 uint[] memory out = abi.decode(data, (uint[]));49 amountsOut[i] = out[out.length - 1];50 }51 postBalance = address(this).balance;52} else {53 // Caller wants to multiswap a token54 require(_amount > 0 && _amount > 10000, "no tokens sent");55 preBalance = IERC20(_token).balanceOf(address(this));56 IERC20(_token).transferFrom(msg.sender, address(this), _amount);57 IERC20(_token).approve(router, _amount);58 for (uint i = 0; i < length; ++i) {59 (bool success, bytes memory data) = router.call(_swapData[i]);60 if (!success) revert ErrorSwapping(i);61 uint[] memory out = abi.decode(data, (uint[]));62 amountsOut[i] = out[out.length - 1];63 }64 postBalance = IERC20(_token).balanceOf(address(this));65}Recommendation:
We advise only the greater-than comparison with a positive number to be retained as it indirectly guarantees that the greater-than zero evaluation will yield true.
Alleviation:
The Xcaliswap team is now only evaluating the greater-than zero check.
MPA-03C: Repetitive Value Literal
| Type | Severity | Location |
|---|---|---|
| Code Style | | Multiswap.sol:L42, L45, L54, L86 |
Description:
The linked value literal is repeated across the codebase multiple times.
Example:
42require(msg.value > 0 && msg.value > 10000, "no ETH sent");Recommendation:
We advise it to be set to a constant variable instead optimizing the legibility of the codebase.
Alleviation:
The Xcaliswap team evaluated this exhibit but opted not to apply any changes for it in the current iteration of the protocol.