Function: transferCallback(IERC20 token, address from, uint256 amount)

This function is used to transfer ERC-20 tokens to smart vault. It is expected to be called from the smart vault during _depositERC20.

Inputs

• token

  • Control: Not controllable, declared underlyingAsset.

  • Constraints: None.

  • Impact: Address of the token.

• from

  • Control: Not controllable,

  • Constraints: Should be the address of the depositor (caller of depositERC20).

  • Impact: Address of the depositor.

• amount

  • Control: Fully controllable by the caller.

  • Constraints: Should be approved by the depositor.

  • Impact: Amount of token.

Branches and code coverage

Intended branches

• Check if the caller is the smart vault.

  Test coverage

• Call safeTransferFrom on the token.

  Test coverage

• Check if the balance of the token is changed correctly.

  Test coverage

Negative behavior

• Revert if the caller is not the smart vault.

  Negative test

• Revert if the balance of the token is changed unexpectedly.

  Negative test

Function call analysis

• token.balanceOf(msg.sender)

  • What is controllable? token, but underlyingAsset is declared in the vault.

  • If the return value is controllable, how is it used and how can it go wrong? Even without an actual token transfer, the callback can still succeed.

  • What happens if it reverts, reenters or does other unusual control flow? A revert indicates that the token address is not valid ERC-20.

• SafeERC20.safeTransferFrom(token, from, msg.sender, amount)

  • What is controllable? token, but underlyingAsset is declared in the vault.

  • If the return value is controllable, how is it used and how can it go wrong? Even without an actual token transfer, the callback can still succeed.

  • What happens if it reverts, reenters or does other unusual control flow? A revert indicates that the token is not a valid ERC-20 or that the sender lacks sufficient balance or approval.

• token.balanceOf(msg.sender)

  • What is controllable? token, but underlyingAsset is declared in the vault.

  • If the return value is controllable, how is it used and how can it go wrong? Even without an actual token transfer, the callback can still succeed.

  • What happens if it reverts, reenters or does other unusual control flow? A revert indicates that the token address is not valid ERC-20.