Function: bridgeToChiaWithPermit(address _assetContract, byte[32] _receiver, uint256 _amount, uint256 _deadline, uint8 _v, byte[32] _r, byte[32] _s)

This function is used to bridge ERC-20 tokens to Chia with a permit allowing token spending. This function uses an ERC-20 permit for gas-efficient token approval and transfer in a single transaction.

Inputs

• _assetContract

  • Control: Arbitrary.

  • Constraints: None.

  • Impact: Address of the ERC-20 token to bridge.

• _receiver

  • Control: Arbitrary.

  • Constraints: None.

  • Impact: Receiver puzzle hash for the wrapped tokens.

• _amount

  • Control: Arbitrary.

  • Constraints: None.

  • Impact: Amount to bridge to Chia, in Mojos.

• _deadline

  • Control: Arbitrary.

  • Constraints: None.

  • Impact: Value of the permit deadline.

• _v

  • Control: Arbitrary.

  • Constraints: None.

  • Impact: Value of the permit signature v.

• _r

  • Control: Arbitrary.

  • Constraints: None.

  • Impact: Value of the permit signature r.

• _s

  • Control: Arbitrary.

  • Constraints: None.

  • Impact: Value of the permit signature s.

Branches and code coverage

Intended branches

• Call the decimals function of the asset contract and update the factor.

  Test coverage

• Call the permit function of target asset contract.

  Test coverage

• Invoke the _handleBridging function.

  Test coverage

Negative behavior

• Revert if msg.value is not equal to the message toll.

  Negative test

Function call analysis

• ERC20Decimals(_assetContract).decimals()

  • What is controllable? _assetContract — it is not whitelisted.

  • If the return value is controllable, how is it used and how can it go wrong? If the decimals of the asset contract are manipulated, the factor will be set arbitrarily.

• IERC20Permit(_assetContract).permit(msg.sender, address(this), _amount * factor, _deadline, _v, _r, _s)

  • What is controllable? _assetContract — it is not whitelisted.