SelfPermit

Functionality to call permit on any EIP-2612-compliant token for use in the route

These functions are expected to be embedded in multicalls to allow EOAs to approve a contract and call a function that requires an approval in a single transaction.

Functions​

selfPermit​

  function selfPermit(
    address token,
    uint256 value,
    uint256 deadline,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) public

Permits this contract to spend a given token from msg.sender

The owner is always msg.sender and the spender is always address(this).

Parameters:​

Name	Type	Description
token	address	The address of the token spent
value	uint256	The amount that can be spent of token
deadline	uint256	A timestamp, the current blocktime must be less than or equal to this timestamp
v	uint8	Must produce valid secp256k1 signature from the holder along with r and s
r	bytes32	Must produce valid secp256k1 signature from the holder along with v and s
s	bytes32	Must produce valid secp256k1 signature from the holder along with r and v

selfPermitIfNecessary​

  function selfPermitIfNecessary(
    address token,
    uint256 value,
    uint256 deadline,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external

Permits this contract to spend a given token from msg.sender

The owner is always msg.sender and the spender is always address(this). Can be used instead of #selfPermit to prevent calls from failing due to a frontrun of a call to #selfPermit

Parameters:​

Name	Type	Description
token	address	The address of the token spent
value	uint256	The amount that can be spent of token
deadline	uint256	A timestamp, the current blocktime must be less than or equal to this timestamp
v	uint8	Must produce valid secp256k1 signature from the holder along with r and s
r	bytes32	Must produce valid secp256k1 signature from the holder along with v and s
s	bytes32	Must produce valid secp256k1 signature from the holder along with r and v

selfPermitAllowed​

  function selfPermitAllowed(
    address token,
    uint256 nonce,
    uint256 expiry,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) public

Permits this contract to spend the sender's tokens for permit signatures that have the allowed parameter

The owner is always msg.sender and the spender is always address(this)

Parameters:​

Name	Type	Description
token	address	The address of the token spent
nonce	uint256	The current nonce of the owner
expiry	uint256	The timestamp at which the permit is no longer valid
v	uint8	Must produce valid secp256k1 signature from the holder along with r and s
r	bytes32	Must produce valid secp256k1 signature from the holder along with v and s
s	bytes32	Must produce valid secp256k1 signature from the holder along with r and v

selfPermitAllowedIfNecessary​

  function selfPermitAllowedIfNecessary(
    address token,
    uint256 nonce,
    uint256 expiry,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external

Permits this contract to spend the sender's tokens for permit signatures that have the allowed parameter

The owner is always msg.sender and the spender is always address(this) Can be used instead of #selfPermitAllowed to prevent calls from failing due to a frontrun of a call to #selfPermitAllowed.

Parameters:​

Name	Type	Description
token	address	The address of the token spent
nonce	uint256	The current nonce of the owner
expiry	uint256	The timestamp at which the permit is no longer valid
v	uint8	Must produce valid secp256k1 signature from the holder along with r and s
r	bytes32	Must produce valid secp256k1 signature from the holder along with v and s
s	bytes32	Must produce valid secp256k1 signature from the holder along with r and v