EIP3009

Git Source

Inherits: ERC20, EIP712Domain

SPDX-License-Identifier: MIT Copyright (c) 2020 CENTRE SECZ Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

State Variables

TRANSFER_WITH_AUTHORIZATION_TYPEHASH

bytes32 public constant TRANSFER_WITH_AUTHORIZATION_TYPEHASH =
    0x7c7c6cdb67a18743f49ec6fa9b35f50d52ed05cbed4cc592e13b44501c1a2267;

RECEIVE_WITH_AUTHORIZATION_TYPEHASH

bytes32 public constant RECEIVE_WITH_AUTHORIZATION_TYPEHASH =
    0xd099cc98ef71107a616c4f0f941f04c322d8e254fe26b3c6668db87aae413de8;

CANCEL_AUTHORIZATION_TYPEHASH

bytes32 public constant CANCEL_AUTHORIZATION_TYPEHASH =
    0x158b0a9edf7a828aad02f63cd515c68ef2f50ba807396f6d12842833a1597429;

_authorizationStates

authorizer address => nonce => state (true = used / false = unused)

mapping(address => mapping(bytes32 => bool)) internal _authorizationStates;

_INVALID_SIGNATURE_ERROR

string internal constant _INVALID_SIGNATURE_ERROR = "EIP3009: invalid signature";

_AUTHORIZATION_USED_ERROR

string internal constant _AUTHORIZATION_USED_ERROR = "EIP3009: authorization is used";

Functions

authorizationState

Returns the state of an authorization

Nonces are randomly generated 32-byte data unique to the authorizer's address

function authorizationState(address authorizer, bytes32 nonce) external view returns (bool);

Parameters

Returns

transferWithAuthorization

Execute a transfer with a signed authorization

function transferWithAuthorization(
    address from,
    address to,
    uint256 value,
    uint256 validAfter,
    uint256 validBefore,
    bytes32 nonce,
    uint8 v,
    bytes32 r,
    bytes32 s
) external;

Parameters

receiveWithAuthorization

Receive a transfer with a signed authorization from the payer

This has an additional check to ensure that the payee's address matches the caller of this function to prevent front-running attacks. (See security considerations)

function receiveWithAuthorization(
    address from,
    address to,
    uint256 value,
    uint256 validAfter,
    uint256 validBefore,
    bytes32 nonce,
    uint8 v,
    bytes32 r,
    bytes32 s
) external;

Parameters

cancelAuthorization

Attempt to cancel an authorization

function cancelAuthorization(address authorizer, bytes32 nonce, uint8 v, bytes32 r, bytes32 s) external;

Parameters

_transferWithAuthorization

function _transferWithAuthorization(
    bytes32 typeHash,
    address from,
    address to,
    uint256 value,
    uint256 validAfter,
    uint256 validBefore,
    bytes32 nonce,
    uint8 v,
    bytes32 r,
    bytes32 s
) internal;

Events

AuthorizationUsed

event AuthorizationUsed(address indexed authorizer, bytes32 indexed nonce);

AuthorizationCanceled

event AuthorizationCanceled(address indexed authorizer, bytes32 indexed nonce);