Contract Name:
Erc20TransferHandler
Contract Source Code:
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable2Step.sol)
pragma solidity ^0.8.0;
import "./Ownable.sol";
/**
* @dev Contract module which provides access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership} and {acceptOwnership}.
*
* This module is used through inheritance. It will make available all functions
* from parent (Ownable).
*/
abstract contract Ownable2Step is Ownable {
address private _pendingOwner;
event OwnershipTransferStarted(address indexed previousOwner, address indexed newOwner);
/**
* @dev Returns the address of the pending owner.
*/
function pendingOwner() public view virtual returns (address) {
return _pendingOwner;
}
/**
* @dev Starts the ownership transfer of the contract to a new account. Replaces the pending transfer if there is one.
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual override onlyOwner {
_pendingOwner = newOwner;
emit OwnershipTransferStarted(owner(), newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`) and deletes any pending owner.
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual override {
delete _pendingOwner;
super._transferOwnership(newOwner);
}
/**
* @dev The new owner accepts the ownership transfer.
*/
function acceptOwnership() public virtual {
address sender = _msgSender();
require(pendingOwner() == sender, "Ownable2Step: caller is not the new owner");
_transferOwnership(sender);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which allows children to implement an emergency stop
* mechanism that can be triggered by an authorized account.
*
* This module is used through inheritance. It will make available the
* modifiers `whenNotPaused` and `whenPaused`, which can be applied to
* the functions of your contract. Note that they will not be pausable by
* simply including this module, only once the modifiers are put in place.
*/
abstract contract Pausable is Context {
/**
* @dev Emitted when the pause is triggered by `account`.
*/
event Paused(address account);
/**
* @dev Emitted when the pause is lifted by `account`.
*/
event Unpaused(address account);
bool private _paused;
/**
* @dev Initializes the contract in unpaused state.
*/
constructor() {
_paused = false;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*
* Requirements:
*
* - The contract must not be paused.
*/
modifier whenNotPaused() {
_requireNotPaused();
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*
* Requirements:
*
* - The contract must be paused.
*/
modifier whenPaused() {
_requirePaused();
_;
}
/**
* @dev Returns true if the contract is paused, and false otherwise.
*/
function paused() public view virtual returns (bool) {
return _paused;
}
/**
* @dev Throws if the contract is paused.
*/
function _requireNotPaused() internal view virtual {
require(!paused(), "Pausable: paused");
}
/**
* @dev Throws if the contract is not paused.
*/
function _requirePaused() internal view virtual {
require(paused(), "Pausable: not paused");
}
/**
* @dev Triggers stopped state.
*
* Requirements:
*
* - The contract must not be paused.
*/
function _pause() internal virtual whenNotPaused {
_paused = true;
emit Paused(_msgSender());
}
/**
* @dev Returns to normal state.
*
* Requirements:
*
* - The contract must be paused.
*/
function _unpause() internal virtual whenPaused {
_paused = false;
emit Unpaused(_msgSender());
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function _nonReentrantBefore() private {
// On the first call to nonReentrant, _status will be _NOT_ENTERED
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
}
function _nonReentrantAfter() private {
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
/**
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
* `nonReentrant` function in the call stack.
*/
function _reentrancyGuardEntered() internal view returns (bool) {
return _status == _ENTERED;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*
* _Available since v4.1._
*/
interface IERC20Metadata is IERC20 {
/**
* @dev Returns the name of the token.
*/
function name() external view returns (string memory);
/**
* @dev Returns the symbol of the token.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the decimals places of the token.
*/
function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*/
interface IERC20Permit {
/**
* @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
* given ``owner``'s signed approval.
*
* IMPORTANT: The same issues {IERC20-approve} has related to transaction
* ordering also apply here.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `deadline` must be a timestamp in the future.
* - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
* over the EIP712-formatted function arguments.
* - the signature must use ``owner``'s current nonce (see {nonces}).
*
* For more information on the signature format, see the
* https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
* section].
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
/**
* @dev Returns the current nonce for `owner`. This value must be
* included whenever a signature is generated for {permit}.
*
* Every successful call to {permit} increases ``owner``'s nonce by one. This
* prevents a signature from being used multiple times.
*/
function nonces(address owner) external view returns (uint256);
/**
* @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../extensions/IERC20Permit.sol";
import "../../../utils/Address.sol";
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using Address for address;
/**
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
/**
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
*/
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
require(
(value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
/**
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 oldAllowance = token.allowance(address(this), spender);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
}
/**
* @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
}
}
/**
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
* to be set to zero before setting it to a non-zero value, such as USDT.
*/
function forceApprove(IERC20 token, address spender, uint256 value) internal {
bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);
if (!_callOptionalReturnBool(token, approvalCall)) {
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
_callOptionalReturn(token, approvalCall);
}
}
/**
* @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
* Revert on invalid signature.
*/
function safePermit(
IERC20Permit token,
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) internal {
uint256 nonceBefore = token.nonces(owner);
token.permit(owner, spender, value, deadline, v, r, s);
uint256 nonceAfter = token.nonces(owner);
require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*
* This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
*/
function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
// and not revert is the subcall reverts.
(bool success, bytes memory returndata) = address(token).call(data);
return
success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
*
* Furthermore, `isContract` will also return true if the target contract within
* the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
* which only has an effect at the end of a transaction.
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
*
* _Available since v4.8._
*/
function verifyCallResultFromTarget(
address target,
bool success,
bytes memory returndata,
string memory errorMessage
) internal view returns (bytes memory) {
if (success) {
if (returndata.length == 0) {
// only check isContract if the call was successful and the return data is empty
// otherwise we already know that it was a contract
require(isContract(target), "Address: call to non-contract");
}
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
/**
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason or using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
function _revert(bytes memory returndata, string memory errorMessage) private pure {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {Ownable2Step} from "@openzeppelin/contracts/access/Ownable2Step.sol";
import {Pausable} from "@openzeppelin/contracts/security/Pausable.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
/**
* Provides set of properties, functions, and modifiers to help with
* security and access control of extending contracts
*/
contract ArcBase is Ownable2Step, Pausable, ReentrancyGuard
{
function pause() public onlyOwner
{
_pause();
}
function unpause() public onlyOwner
{
_unpause();
}
function withdrawNative(address beneficiary) public onlyOwner {
uint256 amount = address(this).balance;
(bool sent, ) = beneficiary.call{value: amount}("");
require(sent, 'Unable to withdraw');
}
function withdrawToken(address beneficiary, address token) public onlyOwner {
uint256 amount = IERC20(token).balanceOf(address(this));
IERC20(token).transfer(beneficiary, amount);
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {ArcBase} from "./ArcBase.sol";
import {IRainbowRoad} from "../interfaces/IRainbowRoad.sol";
/**
* Extends the ArcBase contract to provide
* for interactions with the Rainbow Road
*/
contract ArcBaseWithRainbowRoad is ArcBase
{
IRainbowRoad public rainbowRoad;
constructor(address _rainbowRoad)
{
require(_rainbowRoad != address(0), 'Rainbow Road cannot be zero address');
rainbowRoad = IRainbowRoad(_rainbowRoad);
}
function setRainbowRoad(address _rainbowRoad) external onlyOwner
{
require(_rainbowRoad != address(0), 'Rainbow Road cannot be zero address');
rainbowRoad = IRainbowRoad(_rainbowRoad);
}
/// @dev Only calls from the Rainbow Road are accepted.
modifier onlyRainbowRoad()
{
require(msg.sender == address(rainbowRoad), 'Must be called by Rainbow Road');
_;
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {IERC20Metadata} from "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import {ArcBaseWithRainbowRoad} from "../bases/ArcBaseWithRainbowRoad.sol";
import {IHandler} from "../interfaces/IHandler.sol";
import {IFeeCollectorFactory} from "../interfaces/IFeeCollectorFactory.sol";
import {IFeeCollector} from "../interfaces/IFeeCollector.sol";
import {IMintBurn} from "../interfaces/IMintBurn.sol";
/**
* ERC20 Transfer Handler
*/
contract Erc20TransferHandler is ArcBaseWithRainbowRoad, IHandler
{
using SafeERC20 for IERC20;
bool public chargeTxFee;
uint256 public txFeeRate;
uint256 public bribeFeeRate;
uint256 public constant MAX_TX_FEE_RATE = 200; // 20%
uint256 public constant MAX_BRIBE_FEE_RATE = 1000; // 100%
uint256 public constant MAX_FEE_ON_TRANSFER_PCT_RATE = 1000; // 100%
address public bribeCollector;
IFeeCollectorFactory public feeCollectorFactory;
mapping(string => address) public feeCollectors;
mapping(string => uint256) public feeOnTransferFlatRate;
mapping(string => uint256) public feeOnTransferPercentageRate;
mapping(string => bool) public isMintBurn;
constructor(address _rainbowRoad, address _feeCollectorFactory) ArcBaseWithRainbowRoad(_rainbowRoad)
{
require(_feeCollectorFactory != address(0), 'Fee Collector Factory cannot be zero address');
chargeTxFee = true;
txFeeRate = 2; // 25 bps = 0.2%
bribeFeeRate = 300; // 300 bps = 30%
bribeCollector = 0x1d9E69A851b2c439A964d8dc3d611781440fd658;
feeCollectorFactory = IFeeCollectorFactory(_feeCollectorFactory);
}
function enableTxFeeCharge() external onlyOwner
{
require(!chargeTxFee, 'Charge tx fee is enabled');
chargeTxFee = true;
}
function disableTxFeeCharge() external onlyOwner
{
require(chargeTxFee, 'Charge tx fee is disabled');
chargeTxFee = false;
}
function enableMintBurn(string calldata tokenSymbol) external onlyOwner
{
require(!isMintBurn[tokenSymbol], 'Mint and burn is enabled');
isMintBurn[tokenSymbol] = true;
}
function disableMintBurn(string calldata tokenSymbol) external onlyOwner
{
require(isMintBurn[tokenSymbol], 'Mint and burn is disabled');
isMintBurn[tokenSymbol] = false;
}
function setTxFeeRate(uint256 _txFeeRate) external {
require(rainbowRoad.feeManagers(msg.sender), 'Invalid fee manager');
require(_txFeeRate <= MAX_TX_FEE_RATE, 'Tx fee rate too high');
txFeeRate = _txFeeRate;
}
function setBribeFeeRate(uint256 _bribeFeeRate) external {
require(rainbowRoad.feeManagers(msg.sender), 'Invalid fee manager');
require(_bribeFeeRate <= MAX_BRIBE_FEE_RATE, 'Bribe fee rate too high');
bribeFeeRate = _bribeFeeRate;
}
function setFeeOnTransferFlatRate(string calldata tokenSymbol, uint256 _feeOnTransferFlatRate) external {
require(rainbowRoad.feeManagers(msg.sender), 'Invalid fee manager');
address tokenAddress = rainbowRoad.tokens(tokenSymbol);
require(tokenAddress != address(0), 'Token must be whitelisted');
require(!rainbowRoad.blockedTokens(tokenAddress), 'Token is blocked');
feeOnTransferFlatRate[tokenSymbol] = _feeOnTransferFlatRate;
}
function setFeeOnTransferPercentageRate(string calldata tokenSymbol, uint256 _feeOnTransferPercentageRate) external {
require(rainbowRoad.feeManagers(msg.sender), 'Invalid fee manager');
address tokenAddress = rainbowRoad.tokens(tokenSymbol);
require(tokenAddress != address(0), 'Token must be whitelisted');
require(!rainbowRoad.blockedTokens(tokenAddress), 'Token is blocked');
require(_feeOnTransferPercentageRate <= MAX_FEE_ON_TRANSFER_PCT_RATE, 'Fee on transfer rate too high');
feeOnTransferPercentageRate[tokenSymbol] = _feeOnTransferPercentageRate;
}
function setBribeCollector(address _bribeCollector) external onlyOwner {
bribeCollector = _bribeCollector;
}
function setFeeCollectorFactory(address _feeCollectorFactory) external onlyOwner
{
require(_feeCollectorFactory != address(0), 'Fee Collector Factory cannot be zero address');
feeCollectorFactory = IFeeCollectorFactory(_feeCollectorFactory);
}
function setFeeCollector(string calldata tokenSymbol, address feeCollectorAddress) external onlyOwner
{
address tokenAddress = rainbowRoad.tokens(tokenSymbol);
require(tokenAddress != address(0), 'Token must be whitelisted');
require(!rainbowRoad.blockedTokens(tokenAddress), 'Token is blocked');
require(feeCollectorAddress != address(0), 'Fee collector cannot be zero address');
feeCollectors[tokenSymbol] = feeCollectorAddress;
}
function encodePayload(string calldata tokenSymbol, uint256 amount) view external returns (bytes memory payload)
{
address tokenAddress = rainbowRoad.tokens(tokenSymbol);
require(tokenAddress != address(0), 'Token must be whitelisted');
require(!rainbowRoad.blockedTokens(tokenAddress), 'Token is blocked');
require(amount > 0, 'Invalid amount');
uint256 amountToSend = amount;
if(feeOnTransferPercentageRate[tokenSymbol] > 0) {
uint256 transferFee = (feeOnTransferPercentageRate[tokenSymbol] * amount) / 1000;
require(amountToSend > transferFee, 'Insufficient amount to send : Percent Rate');
amountToSend = amountToSend - transferFee;
}
if(feeOnTransferFlatRate[tokenSymbol] > 0) {
require(amountToSend > feeOnTransferFlatRate[tokenSymbol], 'Insufficient amount to send : Flat Rate');
amountToSend = amountToSend - feeOnTransferFlatRate[tokenSymbol];
}
return abi.encode(tokenSymbol, amountToSend, amount - amountToSend);
}
function handleReceive(address target, bytes calldata payload) external onlyRainbowRoad whenNotPaused nonReentrant
{
(string memory tokenSymbol, uint256 amount) = abi.decode(payload, (string, uint256));
require(amount > 0, 'Invalid amount');
address tokenAddress = rainbowRoad.tokens(tokenSymbol);
require(tokenAddress != address(0), 'Token must be whitelisted');
require(!rainbowRoad.blockedTokens(tokenAddress), 'Token is blocked');
if(isMintBurn[tokenSymbol]) {
IMintBurn(tokenAddress).mint(address(this), amount);
}
IERC20 token = IERC20(tokenAddress);
require(token.balanceOf(address(this)) >= amount, 'Insufficient funds for transfer');
uint256 txFee = 0;
if(chargeTxFee) {
txFee = (txFeeRate * amount) / 1000;
uint256 bribeFee = (bribeFeeRate * txFee) / 1000;
uint256 lpFee = txFee - bribeFee;
if(bribeFee > 0) {
token.safeTransfer(bribeCollector, bribeFee);
}
if(feeCollectors[tokenSymbol] == address(0)) {
feeCollectors[tokenSymbol] = feeCollectorFactory.createFeeCollector(address(rainbowRoad), address(this));
}
if(lpFee > 0) {
token.approve(feeCollectors[tokenSymbol], lpFee);
IFeeCollector(feeCollectors[tokenSymbol]).notifyRewardAmount(tokenAddress, lpFee);
}
}
token.safeTransfer(target, amount - txFee);
}
function handleSend(address target, bytes calldata payload) external onlyRainbowRoad whenNotPaused nonReentrant
{
(string memory tokenSymbol, uint256 amount, uint256 feeOnTransferAmount) = abi.decode(payload, (string, uint256, uint256));
require(amount > 0, 'Invalid amount');
address tokenAddress = rainbowRoad.tokens(tokenSymbol);
require(tokenAddress != address(0), 'Token must be whitelisted');
require(!rainbowRoad.blockedTokens(tokenAddress), 'Token is blocked');
uint256 feeOnTransfer = feeOnTransferAmount;
if(feeOnTransferPercentageRate[tokenSymbol] > 0) {
uint256 transferFee = (feeOnTransferPercentageRate[tokenSymbol] * (amount + feeOnTransferAmount)) / 1000;
require(feeOnTransfer >= transferFee, 'Insufficient amount to send : Percent Rate');
feeOnTransfer = feeOnTransfer - transferFee;
}
if(feeOnTransferFlatRate[tokenSymbol] > 0) {
require(feeOnTransfer >= feeOnTransferFlatRate[tokenSymbol], 'Insufficient amount to send : Flat Rate');
feeOnTransfer = feeOnTransfer - feeOnTransferFlatRate[tokenSymbol];
}
require(feeOnTransfer == 0, 'Invalid fee on transfer amount');
uint256 amountToSend = amount + feeOnTransferAmount;
IERC20 token = IERC20(tokenAddress);
require(token.balanceOf(target) >= amountToSend, 'Target has insufficient balance for transfer');
uint256 preTransferBalance = token.balanceOf(address(this));
token.safeTransferFrom(target, address(this), amountToSend);
uint256 postTransferBalance = token.balanceOf(address(this));
uint256 diffTransferBalance = postTransferBalance - preTransferBalance;
require(diffTransferBalance >= amount, 'Invalid transfer amount');
if(isMintBurn[tokenSymbol]) {
IMintBurn(tokenAddress).burn(amountToSend);
}
}
function deposit(string calldata tokenSymbol, uint256 amount) external nonReentrant
{
require(rainbowRoad.tokens(tokenSymbol) != address(0), 'Token must be whitelisted');
require(amount > 0, 'Invalid amount');
address tokenAddress = rainbowRoad.tokens(tokenSymbol);
require(tokenAddress != address(0), 'Token address cannot be zero address');
require(!rainbowRoad.blockedTokens(tokenAddress), 'Token is blocked');
if(feeCollectors[tokenSymbol] == address(0)) {
feeCollectors[tokenSymbol] = feeCollectorFactory.createFeeCollector(address(rainbowRoad), address(this));
}
IERC20 token = IERC20(tokenAddress);
uint256 preDepositBalance = token.balanceOf(address(this));
token.safeTransferFrom(msg.sender, address(this), amount);
uint256 postDepositBalance = token.balanceOf(address(this));
uint256 diffDepositBalance = postDepositBalance - preDepositBalance;
IFeeCollector(feeCollectors[tokenSymbol]).deposit(msg.sender, diffDepositBalance);
}
function withdraw(string calldata tokenSymbol, uint256 amount) external nonReentrant
{
require(rainbowRoad.tokens(tokenSymbol) != address(0), 'Token must be whitelisted');
require(amount > 0, 'Invalid amount');
address tokenAddress = rainbowRoad.tokens(tokenSymbol);
require(tokenAddress != address(0), 'Token address cannot be zero address');
require(!rainbowRoad.blockedTokens(tokenAddress), 'Token is blocked');
require(feeCollectors[tokenSymbol] != address(0), 'No fee collector found');
IERC20 token = IERC20(tokenAddress);
require(token.balanceOf(address(this)) >= amount, 'Insufficient liquidity for withdrawal');
IFeeCollector feeCollector = IFeeCollector(feeCollectors[tokenSymbol]);
require(feeCollector.balanceOf(msg.sender) >= amount, 'Insufficient account balance for withdrawal');
feeCollector.withdraw(msg.sender, amount);
token.safeTransfer(msg.sender, amount);
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IArc {
function approve(address _spender, uint _value) external returns (bool);
function burn(uint amount) external;
function mint(address account, uint amount) external;
function transfer(address, uint) external returns (bool);
function transferFrom(address _from, address _to, uint _value) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IFeeCollector {
function balanceLockExpires(address account) external view returns (uint);
function balanceOf(address account) external returns (uint);
function deposit(address account, uint amount) external;
function earned(address token, address account) external view returns (uint);
function getEpochStart(uint timestamp) external pure returns (uint);
function getReward(address[] memory tokens) external;
function isBalanceLockExpired(address account) external view returns (bool);
function left(address token) external view returns (uint);
function notifyRewardAmount(address token, uint amount) external;
function withdraw(address account, uint amount) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IFeeCollectorFactory {
function createFeeCollector(address rainbowRoad, address authorizedAccount) external returns (address);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IHandler {
function handleReceive(address target, bytes calldata payload) external;
function handleSend(address target, bytes calldata payload) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IMintBurn {
function burn(uint amount) external;
function mint(address account, uint amount) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {IArc} from "./IArc.sol";
interface IRainbowRoad {
function acceptTeam() external;
function actionHandlers(string calldata action) external view returns (address);
function arc() external view returns (IArc);
function blockToken(address tokenAddress) external;
function disableFeeManager(address feeManager) external;
function disableOpenTokenWhitelisting() external;
function disableReceiver(address receiver) external;
function disableSender(address sender) external;
function disableSendFeeBurn() external;
function disableSendFeeCharge() external;
function disableWhitelistingFeeBurn() external;
function disableWhitelistingFeeCharge() external;
function enableFeeManager(address feeManager) external;
function enableOpenTokenWhitelisting() external;
function enableReceiver(address receiver) external;
function enableSendFeeBurn() external;
function enableSender(address sender) external;
function enableSendFeeCharge() external;
function enableWhitelistingFeeBurn() external;
function enableWhitelistingFeeCharge() external;
function sendFee() external view returns (uint256);
function whitelistingFee() external view returns (uint256);
function chargeSendFee() external view returns (bool);
function chargeWhitelistingFee() external view returns (bool);
function burnSendFee() external view returns (bool);
function burnWhitelistingFee() external view returns (bool);
function openTokenWhitelisting() external view returns (bool);
function config(string calldata configName) external view returns (bytes memory);
function blockedTokens(address tokenAddress) external view returns (bool);
function feeManagers(address feeManager) external view returns (bool);
function receiveAction(string calldata action, address to, bytes calldata payload) external;
function sendAction(string calldata action, address from, bytes calldata payload) external;
function setActionHandler(string memory action, address handler) external;
function setArc(address _arc) external;
function setSendFee(uint256 _fee) external;
function setTeam(address _team) external;
function setTeamRate(uint256 _teamRate) external;
function setToken(string calldata tokenSymbol, address tokenAddress) external;
function setWhitelistingFee(uint256 _fee) external;
function team() external view returns (address);
function teamRate() external view returns (uint256);
function tokens(string calldata tokenSymbol) external view returns (address);
function MAX_TEAM_RATE() external view returns (uint256);
function receivers(address receiver) external view returns (bool);
function senders(address sender) external view returns (bool);
function unblockToken(address tokenAddress) external;
function whitelist(address tokenAddress) external;
}