Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
import { IMessageLibManager } from "./IMessageLibManager.sol";
import { IMessagingComposer } from "./IMessagingComposer.sol";
import { IMessagingChannel } from "./IMessagingChannel.sol";
import { IMessagingContext } from "./IMessagingContext.sol";
struct MessagingParams {
uint32 dstEid;
bytes32 receiver;
bytes message;
bytes options;
bool payInLzToken;
}
struct MessagingReceipt {
bytes32 guid;
uint64 nonce;
MessagingFee fee;
}
struct MessagingFee {
uint256 nativeFee;
uint256 lzTokenFee;
}
struct Origin {
uint32 srcEid;
bytes32 sender;
uint64 nonce;
}
interface ILayerZeroEndpointV2 is IMessageLibManager, IMessagingComposer, IMessagingChannel, IMessagingContext {
event PacketSent(bytes encodedPayload, bytes options, address sendLibrary);
event PacketVerified(Origin origin, address receiver, bytes32 payloadHash);
event PacketDelivered(Origin origin, address receiver);
event LzReceiveAlert(
address indexed receiver,
address indexed executor,
Origin origin,
bytes32 guid,
uint256 gas,
uint256 value,
bytes message,
bytes extraData,
bytes reason
);
event LzTokenSet(address token);
event DelegateSet(address sender, address delegate);
function quote(MessagingParams calldata _params, address _sender) external view returns (MessagingFee memory);
function send(
MessagingParams calldata _params,
address _refundAddress
) external payable returns (MessagingReceipt memory);
function verify(Origin calldata _origin, address _receiver, bytes32 _payloadHash) external;
function verifiable(Origin calldata _origin, address _receiver) external view returns (bool);
function initializable(Origin calldata _origin, address _receiver) external view returns (bool);
function lzReceive(
Origin calldata _origin,
address _receiver,
bytes32 _guid,
bytes calldata _message,
bytes calldata _extraData
) external payable;
// oapp can burn messages partially by calling this function with its own business logic if messages are verified in order
function clear(address _oapp, Origin calldata _origin, bytes32 _guid, bytes calldata _message) external;
function setLzToken(address _lzToken) external;
function lzToken() external view returns (address);
function nativeToken() external view returns (address);
function setDelegate(address _delegate) external;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
import { Origin } from "./ILayerZeroEndpointV2.sol";
interface ILayerZeroReceiver {
function allowInitializePath(Origin calldata _origin) external view returns (bool);
function nextNonce(uint32 _eid, bytes32 _sender) external view returns (uint64);
function lzReceive(
Origin calldata _origin,
bytes32 _guid,
bytes calldata _message,
address _executor,
bytes calldata _extraData
) external payable;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
struct SetConfigParam {
uint32 eid;
uint32 configType;
bytes config;
}
interface IMessageLibManager {
struct Timeout {
address lib;
uint256 expiry;
}
event LibraryRegistered(address newLib);
event DefaultSendLibrarySet(uint32 eid, address newLib);
event DefaultReceiveLibrarySet(uint32 eid, address newLib);
event DefaultReceiveLibraryTimeoutSet(uint32 eid, address oldLib, uint256 expiry);
event SendLibrarySet(address sender, uint32 eid, address newLib);
event ReceiveLibrarySet(address receiver, uint32 eid, address newLib);
event ReceiveLibraryTimeoutSet(address receiver, uint32 eid, address oldLib, uint256 timeout);
function registerLibrary(address _lib) external;
function isRegisteredLibrary(address _lib) external view returns (bool);
function getRegisteredLibraries() external view returns (address[] memory);
function setDefaultSendLibrary(uint32 _eid, address _newLib) external;
function defaultSendLibrary(uint32 _eid) external view returns (address);
function setDefaultReceiveLibrary(uint32 _eid, address _newLib, uint256 _gracePeriod) external;
function defaultReceiveLibrary(uint32 _eid) external view returns (address);
function setDefaultReceiveLibraryTimeout(uint32 _eid, address _lib, uint256 _expiry) external;
function defaultReceiveLibraryTimeout(uint32 _eid) external view returns (address lib, uint256 expiry);
function isSupportedEid(uint32 _eid) external view returns (bool);
function isValidReceiveLibrary(address _receiver, uint32 _eid, address _lib) external view returns (bool);
/// ------------------- OApp interfaces -------------------
function setSendLibrary(address _oapp, uint32 _eid, address _newLib) external;
function getSendLibrary(address _sender, uint32 _eid) external view returns (address lib);
function isDefaultSendLibrary(address _sender, uint32 _eid) external view returns (bool);
function setReceiveLibrary(address _oapp, uint32 _eid, address _newLib, uint256 _gracePeriod) external;
function getReceiveLibrary(address _receiver, uint32 _eid) external view returns (address lib, bool isDefault);
function setReceiveLibraryTimeout(address _oapp, uint32 _eid, address _lib, uint256 _expiry) external;
function receiveLibraryTimeout(address _receiver, uint32 _eid) external view returns (address lib, uint256 expiry);
function setConfig(address _oapp, address _lib, SetConfigParam[] calldata _params) external;
function getConfig(
address _oapp,
address _lib,
uint32 _eid,
uint32 _configType
) external view returns (bytes memory config);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
interface IMessagingChannel {
event InboundNonceSkipped(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce);
event PacketNilified(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce, bytes32 payloadHash);
event PacketBurnt(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce, bytes32 payloadHash);
function eid() external view returns (uint32);
// this is an emergency function if a message cannot be verified for some reasons
// required to provide _nextNonce to avoid race condition
function skip(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce) external;
function nilify(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce, bytes32 _payloadHash) external;
function burn(address _oapp, uint32 _srcEid, bytes32 _sender, uint64 _nonce, bytes32 _payloadHash) external;
function nextGuid(address _sender, uint32 _dstEid, bytes32 _receiver) external view returns (bytes32);
function inboundNonce(address _receiver, uint32 _srcEid, bytes32 _sender) external view returns (uint64);
function outboundNonce(address _sender, uint32 _dstEid, bytes32 _receiver) external view returns (uint64);
function inboundPayloadHash(
address _receiver,
uint32 _srcEid,
bytes32 _sender,
uint64 _nonce
) external view returns (bytes32);
function lazyInboundNonce(address _receiver, uint32 _srcEid, bytes32 _sender) external view returns (uint64);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
interface IMessagingComposer {
event ComposeSent(address from, address to, bytes32 guid, uint16 index, bytes message);
event ComposeDelivered(address from, address to, bytes32 guid, uint16 index);
event LzComposeAlert(
address indexed from,
address indexed to,
address indexed executor,
bytes32 guid,
uint16 index,
uint256 gas,
uint256 value,
bytes message,
bytes extraData,
bytes reason
);
function composeQueue(
address _from,
address _to,
bytes32 _guid,
uint16 _index
) external view returns (bytes32 messageHash);
function sendCompose(address _to, bytes32 _guid, uint16 _index, bytes calldata _message) external;
function lzCompose(
address _from,
address _to,
bytes32 _guid,
uint16 _index,
bytes calldata _message,
bytes calldata _extraData
) external payable;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
interface IMessagingContext {
function isSendingMessage() external view returns (bool);
function getSendContext() external view returns (uint32 dstEid, address sender);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;
import { ILayerZeroEndpointV2 } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol";
/**
* @title IOAppCore
*/
interface IOAppCore {
// Custom error messages
error OnlyPeer(uint32 eid, bytes32 sender);
error NoPeer(uint32 eid);
error InvalidEndpointCall();
error InvalidDelegate();
// Event emitted when a peer (OApp) is set for a corresponding endpoint
event PeerSet(uint32 eid, bytes32 peer);
/**
* @notice Retrieves the OApp version information.
* @return senderVersion The version of the OAppSender.sol contract.
* @return receiverVersion The version of the OAppReceiver.sol contract.
*/
function oAppVersion() external view returns (uint64 senderVersion, uint64 receiverVersion);
/**
* @notice Retrieves the LayerZero endpoint associated with the OApp.
* @return iEndpoint The LayerZero endpoint as an interface.
*/
function endpoint() external view returns (ILayerZeroEndpointV2 iEndpoint);
/**
* @notice Retrieves the peer (OApp) associated with a corresponding endpoint.
* @param _eid The endpoint ID.
* @return peer The peer address (OApp instance) associated with the corresponding endpoint.
*/
function peers(uint32 _eid) external view returns (bytes32 peer);
/**
* @notice Sets the peer address (OApp instance) for a corresponding endpoint.
* @param _eid The endpoint ID.
* @param _peer The address of the peer to be associated with the corresponding endpoint.
*/
function setPeer(uint32 _eid, bytes32 _peer) external;
/**
* @notice Sets the delegate address for the OApp Core.
* @param _delegate The address of the delegate to be set.
*/
function setDelegate(address _delegate) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;
import { ILayerZeroReceiver, Origin } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroReceiver.sol";
interface IOAppReceiver is ILayerZeroReceiver {
/**
* @notice Indicates whether an address is an approved composeMsg sender to the Endpoint.
* @param _origin The origin information containing the source endpoint and sender address.
* - srcEid: The source chain endpoint ID.
* - sender: The sender address on the src chain.
* - nonce: The nonce of the message.
* @param _message The lzReceive payload.
* @param _sender The sender address.
* @return isSender Is a valid sender.
*
* @dev Applications can optionally choose to implement a separate composeMsg sender that is NOT the bridging layer.
* @dev The default sender IS the OAppReceiver implementer.
*/
function isComposeMsgSender(
Origin calldata _origin,
bytes calldata _message,
address _sender
) external view returns (bool isSender);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;
// @dev Import the 'MessagingFee' and 'MessagingReceipt' so it's exposed to OApp implementers
// solhint-disable-next-line no-unused-import
import { OAppSender, MessagingFee, MessagingReceipt } from "./OAppSender.sol";
// @dev Import the 'Origin' so it's exposed to OApp implementers
// solhint-disable-next-line no-unused-import
import { OAppReceiver, Origin } from "./OAppReceiver.sol";
import { OAppCore } from "./OAppCore.sol";
/**
* @title OApp
* @dev Abstract contract serving as the base for OApp implementation, combining OAppSender and OAppReceiver functionality.
*/
abstract contract OApp is OAppSender, OAppReceiver {
/**
* @dev Constructor to initialize the OApp with the provided endpoint and owner.
* @param _endpoint The address of the LOCAL LayerZero endpoint.
* @param _delegate The delegate capable of making OApp configurations inside of the endpoint.
*/
constructor(address _endpoint, address _delegate) OAppCore(_endpoint, _delegate) {}
/**
* @notice Retrieves the OApp version information.
* @return senderVersion The version of the OAppSender.sol implementation.
* @return receiverVersion The version of the OAppReceiver.sol implementation.
*/
function oAppVersion()
public
pure
virtual
override(OAppSender, OAppReceiver)
returns (uint64 senderVersion, uint64 receiverVersion)
{
return (SENDER_VERSION, RECEIVER_VERSION);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;
import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
import { IOAppCore, ILayerZeroEndpointV2 } from "./interfaces/IOAppCore.sol";
/**
* @title OAppCore
* @dev Abstract contract implementing the IOAppCore interface with basic OApp configurations.
*/
abstract contract OAppCore is IOAppCore, Ownable {
// The LayerZero endpoint associated with the given OApp
ILayerZeroEndpointV2 public immutable endpoint;
// Mapping to store peers associated with corresponding endpoints
mapping(uint32 eid => bytes32 peer) public peers;
/**
* @dev Constructor to initialize the OAppCore with the provided endpoint and delegate.
* @param _endpoint The address of the LOCAL Layer Zero endpoint.
* @param _delegate The delegate capable of making OApp configurations inside of the endpoint.
*
* @dev The delegate typically should be set as the owner of the contract.
*/
constructor(address _endpoint, address _delegate) {
endpoint = ILayerZeroEndpointV2(_endpoint);
if (_delegate == address(0)) revert InvalidDelegate();
endpoint.setDelegate(_delegate);
}
/**
* @notice Sets the peer address (OApp instance) for a corresponding endpoint.
* @param _eid The endpoint ID.
* @param _peer The address of the peer to be associated with the corresponding endpoint.
*
* @dev Only the owner/admin of the OApp can call this function.
* @dev Indicates that the peer is trusted to send LayerZero messages to this OApp.
* @dev Set this to bytes32(0) to remove the peer address.
* @dev Peer is a bytes32 to accommodate non-evm chains.
*/
function setPeer(uint32 _eid, bytes32 _peer) public virtual onlyOwner {
_setPeer(_eid, _peer);
}
/**
* @notice Sets the peer address (OApp instance) for a corresponding endpoint.
* @param _eid The endpoint ID.
* @param _peer The address of the peer to be associated with the corresponding endpoint.
*
* @dev Indicates that the peer is trusted to send LayerZero messages to this OApp.
* @dev Set this to bytes32(0) to remove the peer address.
* @dev Peer is a bytes32 to accommodate non-evm chains.
*/
function _setPeer(uint32 _eid, bytes32 _peer) internal virtual {
peers[_eid] = _peer;
emit PeerSet(_eid, _peer);
}
/**
* @notice Internal function to get the peer address associated with a specific endpoint; reverts if NOT set.
* ie. the peer is set to bytes32(0).
* @param _eid The endpoint ID.
* @return peer The address of the peer associated with the specified endpoint.
*/
function _getPeerOrRevert(uint32 _eid) internal view virtual returns (bytes32) {
bytes32 peer = peers[_eid];
if (peer == bytes32(0)) revert NoPeer(_eid);
return peer;
}
/**
* @notice Sets the delegate address for the OApp.
* @param _delegate The address of the delegate to be set.
*
* @dev Only the owner/admin of the OApp can call this function.
* @dev Provides the ability for a delegate to set configs, on behalf of the OApp, directly on the Endpoint contract.
*/
function setDelegate(address _delegate) public onlyOwner {
endpoint.setDelegate(_delegate);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;
import { IOAppReceiver, Origin } from "./interfaces/IOAppReceiver.sol";
import { OAppCore } from "./OAppCore.sol";
/**
* @title OAppReceiver
* @dev Abstract contract implementing the ILayerZeroReceiver interface and extending OAppCore for OApp receivers.
*/
abstract contract OAppReceiver is IOAppReceiver, OAppCore {
// Custom error message for when the caller is not the registered endpoint/
error OnlyEndpoint(address addr);
// @dev The version of the OAppReceiver implementation.
// @dev Version is bumped when changes are made to this contract.
uint64 internal constant RECEIVER_VERSION = 2;
/**
* @notice Retrieves the OApp version information.
* @return senderVersion The version of the OAppSender.sol contract.
* @return receiverVersion The version of the OAppReceiver.sol contract.
*
* @dev Providing 0 as the default for OAppSender version. Indicates that the OAppSender is not implemented.
* ie. this is a RECEIVE only OApp.
* @dev If the OApp uses both OAppSender and OAppReceiver, then this needs to be override returning the correct versions.
*/
function oAppVersion() public view virtual returns (uint64 senderVersion, uint64 receiverVersion) {
return (0, RECEIVER_VERSION);
}
/**
* @notice Indicates whether an address is an approved composeMsg sender to the Endpoint.
* @dev _origin The origin information containing the source endpoint and sender address.
* - srcEid: The source chain endpoint ID.
* - sender: The sender address on the src chain.
* - nonce: The nonce of the message.
* @dev _message The lzReceive payload.
* @param _sender The sender address.
* @return isSender Is a valid sender.
*
* @dev Applications can optionally choose to implement separate composeMsg senders that are NOT the bridging layer.
* @dev The default sender IS the OAppReceiver implementer.
*/
function isComposeMsgSender(
Origin calldata /*_origin*/,
bytes calldata /*_message*/,
address _sender
) public view virtual returns (bool) {
return _sender == address(this);
}
/**
* @notice Checks if the path initialization is allowed based on the provided origin.
* @param origin The origin information containing the source endpoint and sender address.
* @return Whether the path has been initialized.
*
* @dev This indicates to the endpoint that the OApp has enabled msgs for this particular path to be received.
* @dev This defaults to assuming if a peer has been set, its initialized.
* Can be overridden by the OApp if there is other logic to determine this.
*/
function allowInitializePath(Origin calldata origin) public view virtual returns (bool) {
return peers[origin.srcEid] == origin.sender;
}
/**
* @notice Retrieves the next nonce for a given source endpoint and sender address.
* @dev _srcEid The source endpoint ID.
* @dev _sender The sender address.
* @return nonce The next nonce.
*
* @dev The path nonce starts from 1. If 0 is returned it means that there is NO nonce ordered enforcement.
* @dev Is required by the off-chain executor to determine the OApp expects msg execution is ordered.
* @dev This is also enforced by the OApp.
* @dev By default this is NOT enabled. ie. nextNonce is hardcoded to return 0.
*/
function nextNonce(uint32 /*_srcEid*/, bytes32 /*_sender*/) public view virtual returns (uint64 nonce) {
return 0;
}
/**
* @dev Entry point for receiving messages or packets from the endpoint.
* @param _origin The origin information containing the source endpoint and sender address.
* - srcEid: The source chain endpoint ID.
* - sender: The sender address on the src chain.
* - nonce: The nonce of the message.
* @param _guid The unique identifier for the received LayerZero message.
* @param _message The payload of the received message.
* @param _executor The address of the executor for the received message.
* @param _extraData Additional arbitrary data provided by the corresponding executor.
*
* @dev Entry point for receiving msg/packet from the LayerZero endpoint.
*/
function lzReceive(
Origin calldata _origin,
bytes32 _guid,
bytes calldata _message,
address _executor,
bytes calldata _extraData
) public payable virtual {
// Ensures that only the endpoint can attempt to lzReceive() messages to this OApp.
if (address(endpoint) != msg.sender) revert OnlyEndpoint(msg.sender);
// Ensure that the sender matches the expected peer for the source endpoint.
if (_getPeerOrRevert(_origin.srcEid) != _origin.sender) revert OnlyPeer(_origin.srcEid, _origin.sender);
// Call the internal OApp implementation of lzReceive.
_lzReceive(_origin, _guid, _message, _executor, _extraData);
}
/**
* @dev Internal function to implement lzReceive logic without needing to copy the basic parameter validation.
*/
function _lzReceive(
Origin calldata _origin,
bytes32 _guid,
bytes calldata _message,
address _executor,
bytes calldata _extraData
) internal virtual;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;
import { SafeERC20, IERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import { MessagingParams, MessagingFee, MessagingReceipt } from "@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol";
import { OAppCore } from "./OAppCore.sol";
/**
* @title OAppSender
* @dev Abstract contract implementing the OAppSender functionality for sending messages to a LayerZero endpoint.
*/
abstract contract OAppSender is OAppCore {
using SafeERC20 for IERC20;
// Custom error messages
error NotEnoughNative(uint256 msgValue);
error LzTokenUnavailable();
// @dev The version of the OAppSender implementation.
// @dev Version is bumped when changes are made to this contract.
uint64 internal constant SENDER_VERSION = 1;
/**
* @notice Retrieves the OApp version information.
* @return senderVersion The version of the OAppSender.sol contract.
* @return receiverVersion The version of the OAppReceiver.sol contract.
*
* @dev Providing 0 as the default for OAppReceiver version. Indicates that the OAppReceiver is not implemented.
* ie. this is a SEND only OApp.
* @dev If the OApp uses both OAppSender and OAppReceiver, then this needs to be override returning the correct versions
*/
function oAppVersion() public view virtual returns (uint64 senderVersion, uint64 receiverVersion) {
return (SENDER_VERSION, 0);
}
/**
* @dev Internal function to interact with the LayerZero EndpointV2.quote() for fee calculation.
* @param _dstEid The destination endpoint ID.
* @param _message The message payload.
* @param _options Additional options for the message.
* @param _payInLzToken Flag indicating whether to pay the fee in LZ tokens.
* @return fee The calculated MessagingFee for the message.
* - nativeFee: The native fee for the message.
* - lzTokenFee: The LZ token fee for the message.
*/
function _quote(
uint32 _dstEid,
bytes memory _message,
bytes memory _options,
bool _payInLzToken
) internal view virtual returns (MessagingFee memory fee) {
return
endpoint.quote(
MessagingParams(_dstEid, _getPeerOrRevert(_dstEid), _message, _options, _payInLzToken),
address(this)
);
}
/**
* @dev Internal function to interact with the LayerZero EndpointV2.send() for sending a message.
* @param _dstEid The destination endpoint ID.
* @param _message The message payload.
* @param _options Additional options for the message.
* @param _fee The calculated LayerZero fee for the message.
* - nativeFee: The native fee.
* - lzTokenFee: The lzToken fee.
* @param _refundAddress The address to receive any excess fee values sent to the endpoint.
* @return receipt The receipt for the sent message.
* - guid: The unique identifier for the sent message.
* - nonce: The nonce of the sent message.
* - fee: The LayerZero fee incurred for the message.
*/
function _lzSend(
uint32 _dstEid,
bytes memory _message,
bytes memory _options,
MessagingFee memory _fee,
address _refundAddress
) internal virtual returns (MessagingReceipt memory receipt) {
// @dev Push corresponding fees to the endpoint, any excess is sent back to the _refundAddress from the endpoint.
uint256 messageValue = _payNative(_fee.nativeFee);
if (_fee.lzTokenFee > 0) _payLzToken(_fee.lzTokenFee);
return
// solhint-disable-next-line check-send-result
endpoint.send{ value: messageValue }(
MessagingParams(_dstEid, _getPeerOrRevert(_dstEid), _message, _options, _fee.lzTokenFee > 0),
_refundAddress
);
}
/**
* @dev Internal function to pay the native fee associated with the message.
* @param _nativeFee The native fee to be paid.
* @return nativeFee The amount of native currency paid.
*
* @dev If the OApp needs to initiate MULTIPLE LayerZero messages in a single transaction,
* this will need to be overridden because msg.value would contain multiple lzFees.
* @dev Should be overridden in the event the LayerZero endpoint requires a different native currency.
* @dev Some EVMs use an ERC20 as a method for paying transactions/gasFees.
* @dev The endpoint is EITHER/OR, ie. it will NOT support both types of native payment at a time.
*/
function _payNative(uint256 _nativeFee) internal virtual returns (uint256 nativeFee) {
if (msg.value != _nativeFee) revert NotEnoughNative(msg.value);
return _nativeFee;
}
/**
* @dev Internal function to pay the LZ token fee associated with the message.
* @param _lzTokenFee The LZ token fee to be paid.
*
* @dev If the caller is trying to pay in the specified lzToken, then the lzTokenFee is passed to the endpoint.
* @dev Any excess sent, is passed back to the specified _refundAddress in the _lzSend().
*/
function _payLzToken(uint256 _lzTokenFee) internal virtual {
// @dev Cannot cache the token because it is not immutable in the endpoint.
address lzToken = endpoint.lzToken();
if (lzToken == address(0)) revert LzTokenUnavailable();
// Pay LZ token fee by sending tokens to the endpoint.
IERC20(lzToken).safeTransferFrom(msg.sender, address(endpoint), _lzTokenFee);
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;
import "./ILayerZeroUserApplicationConfig.sol";
interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
// @notice send a LayerZero message to the specified address at a LayerZero endpoint.
// @param _dstChainId - the destination chain identifier
// @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
// @param _payload - a custom bytes payload to send to the destination contract
// @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
// @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
// @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
// @notice used by the messaging library to publish verified payload
// @param _srcChainId - the source chain identifier
// @param _srcAddress - the source contract (as bytes) at the source chain
// @param _dstAddress - the address on destination chain
// @param _nonce - the unbound message ordering nonce
// @param _gasLimit - the gas limit for external contract execution
// @param _payload - verified payload to send to the destination contract
function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;
// @notice get the inboundNonce of a lzApp from a source chain which could be EVM or non-EVM chain
// @param _srcChainId - the source chain identifier
// @param _srcAddress - the source chain contract address
function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);
// @notice get the outboundNonce from this source chain which, consequently, is always an EVM
// @param _srcAddress - the source chain contract address
function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
// @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
// @param _dstChainId - the destination chain identifier
// @param _userApplication - the user app address on this EVM chain
// @param _payload - the custom message to send over LayerZero
// @param _payInZRO - if false, user app pays the protocol fee in native token
// @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
// @notice get this Endpoint's immutable source identifier
function getChainId() external view returns (uint16);
// @notice the interface to retry failed message on this Endpoint destination
// @param _srcChainId - the source chain identifier
// @param _srcAddress - the source chain contract address
// @param _payload - the payload to be retried
function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;
// @notice query if any STORED payload (message blocking) at the endpoint.
// @param _srcChainId - the source chain identifier
// @param _srcAddress - the source chain contract address
function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);
// @notice query if the _libraryAddress is valid for sending msgs.
// @param _userApplication - the user app address on this EVM chain
function getSendLibraryAddress(address _userApplication) external view returns (address);
// @notice query if the _libraryAddress is valid for receiving msgs.
// @param _userApplication - the user app address on this EVM chain
function getReceiveLibraryAddress(address _userApplication) external view returns (address);
// @notice query if the non-reentrancy guard for send() is on
// @return true if the guard is on. false otherwise
function isSendingPayload() external view returns (bool);
// @notice query if the non-reentrancy guard for receive() is on
// @return true if the guard is on. false otherwise
function isReceivingPayload() external view returns (bool);
// @notice get the configuration of the LayerZero messaging library of the specified version
// @param _version - messaging library version
// @param _chainId - the chainId for the pending config change
// @param _userApplication - the contract address of the user application
// @param _configType - type of configuration. every messaging library has its own convention.
function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
// @notice get the send() LayerZero messaging library version
// @param _userApplication - the contract address of the user application
function getSendVersion(address _userApplication) external view returns (uint16);
// @notice get the lzReceive() LayerZero messaging library version
// @param _userApplication - the contract address of the user application
function getReceiveVersion(address _userApplication) external view returns (uint16);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;
interface ILayerZeroReceiver {
// @notice LayerZero endpoint will invoke this function to deliver the message on the destination
// @param _srcChainId - the source endpoint identifier
// @param _srcAddress - the source sending contract address from the source chain
// @param _nonce - the ordered message nonce
// @param _payload - the signed payload is the UA bytes has encoded to be sent
function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) external;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;
interface ILayerZeroUserApplicationConfig {
// @notice set the configuration of the LayerZero messaging library of the specified version
// @param _version - messaging library version
// @param _chainId - the chainId for the pending config change
// @param _configType - type of configuration. every messaging library has its own convention.
// @param _config - configuration in the bytes. can encode arbitrary content.
function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;
// @notice set the send() LayerZero messaging library version to _version
// @param _version - new messaging library version
function setSendVersion(uint16 _version) external;
// @notice set the lzReceive() LayerZero messaging library version to _version
// @param _version - new messaging library version
function setReceiveVersion(uint16 _version) external;
// @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
// @param _srcChainId - the chainId of the source chain
// @param _srcAddress - the contract address of the source contract at the source chain
function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/access/Ownable.sol";
import "../interfaces/ILayerZeroReceiver.sol";
import "../interfaces/ILayerZeroUserApplicationConfig.sol";
import "../interfaces/ILayerZeroEndpoint.sol";
import "../util/BytesLib.sol";
/*
* a generic LzReceiver implementation
*/
abstract contract LzApp is Ownable, ILayerZeroReceiver, ILayerZeroUserApplicationConfig {
using BytesLib for bytes;
// ua can not send payload larger than this by default, but it can be changed by the ua owner
uint constant public DEFAULT_PAYLOAD_SIZE_LIMIT = 10000;
ILayerZeroEndpoint public immutable lzEndpoint;
mapping(uint16 => bytes) public trustedRemoteLookup;
mapping(uint16 => mapping(uint16 => uint)) public minDstGasLookup;
mapping(uint16 => uint) public payloadSizeLimitLookup;
address public precrime;
event SetPrecrime(address precrime);
event SetTrustedRemote(uint16 _remoteChainId, bytes _path);
event SetTrustedRemoteAddress(uint16 _remoteChainId, bytes _remoteAddress);
event SetMinDstGas(uint16 _dstChainId, uint16 _type, uint _minDstGas);
constructor(address _endpoint) {
lzEndpoint = ILayerZeroEndpoint(_endpoint);
}
function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public virtual override {
// lzReceive must be called by the endpoint for security
require(_msgSender() == address(lzEndpoint), "LzApp: invalid endpoint caller");
bytes memory trustedRemote = trustedRemoteLookup[_srcChainId];
// if will still block the message pathway from (srcChainId, srcAddress). should not receive message from untrusted remote.
require(_srcAddress.length == trustedRemote.length && trustedRemote.length > 0 && keccak256(_srcAddress) == keccak256(trustedRemote), "LzApp: invalid source sending contract");
_blockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
}
// abstract function - the default behaviour of LayerZero is blocking. See: NonblockingLzApp if you dont need to enforce ordered messaging
function _blockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual;
function _lzSend(uint16 _dstChainId, bytes memory _payload, address payable _refundAddress, address _zroPaymentAddress, bytes memory _adapterParams, uint _nativeFee) internal virtual {
bytes memory trustedRemote = trustedRemoteLookup[_dstChainId];
require(trustedRemote.length != 0, "LzApp: destination chain is not a trusted source");
_checkPayloadSize(_dstChainId, _payload.length);
lzEndpoint.send{value: _nativeFee}(_dstChainId, trustedRemote, _payload, _refundAddress, _zroPaymentAddress, _adapterParams);
}
function _checkGasLimit(uint16 _dstChainId, uint16 _type, bytes memory _adapterParams, uint _extraGas) internal view virtual {
uint providedGasLimit = _getGasLimit(_adapterParams);
uint minGasLimit = minDstGasLookup[_dstChainId][_type] + _extraGas;
require(minGasLimit > 0, "LzApp: minGasLimit not set");
require(providedGasLimit >= minGasLimit, "LzApp: gas limit is too low");
}
function _getGasLimit(bytes memory _adapterParams) internal pure virtual returns (uint gasLimit) {
require(_adapterParams.length >= 34, "LzApp: invalid adapterParams");
assembly {
gasLimit := mload(add(_adapterParams, 34))
}
}
function _checkPayloadSize(uint16 _dstChainId, uint _payloadSize) internal view virtual {
uint payloadSizeLimit = payloadSizeLimitLookup[_dstChainId];
if (payloadSizeLimit == 0) { // use default if not set
payloadSizeLimit = DEFAULT_PAYLOAD_SIZE_LIMIT;
}
require(_payloadSize <= payloadSizeLimit, "LzApp: payload size is too large");
}
//---------------------------UserApplication config----------------------------------------
function getConfig(uint16 _version, uint16 _chainId, address, uint _configType) external view returns (bytes memory) {
return lzEndpoint.getConfig(_version, _chainId, address(this), _configType);
}
// generic config for LayerZero user Application
function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external override onlyOwner {
lzEndpoint.setConfig(_version, _chainId, _configType, _config);
}
function setSendVersion(uint16 _version) external override onlyOwner {
lzEndpoint.setSendVersion(_version);
}
function setReceiveVersion(uint16 _version) external override onlyOwner {
lzEndpoint.setReceiveVersion(_version);
}
function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external override onlyOwner {
lzEndpoint.forceResumeReceive(_srcChainId, _srcAddress);
}
// _path = abi.encodePacked(remoteAddress, localAddress)
// this function set the trusted path for the cross-chain communication
function setTrustedRemote(uint16 _srcChainId, bytes calldata _path) external onlyOwner {
trustedRemoteLookup[_srcChainId] = _path;
emit SetTrustedRemote(_srcChainId, _path);
}
function setTrustedRemoteAddress(uint16 _remoteChainId, bytes calldata _remoteAddress) external onlyOwner {
trustedRemoteLookup[_remoteChainId] = abi.encodePacked(_remoteAddress, address(this));
emit SetTrustedRemoteAddress(_remoteChainId, _remoteAddress);
}
function getTrustedRemoteAddress(uint16 _remoteChainId) external view returns (bytes memory) {
bytes memory path = trustedRemoteLookup[_remoteChainId];
require(path.length != 0, "LzApp: no trusted path record");
return path.slice(0, path.length - 20); // the last 20 bytes should be address(this)
}
function setPrecrime(address _precrime) external onlyOwner {
precrime = _precrime;
emit SetPrecrime(_precrime);
}
function setMinDstGas(uint16 _dstChainId, uint16 _packetType, uint _minGas) external onlyOwner {
require(_minGas > 0, "LzApp: invalid minGas");
minDstGasLookup[_dstChainId][_packetType] = _minGas;
emit SetMinDstGas(_dstChainId, _packetType, _minGas);
}
// if the size is 0, it means default size limit
function setPayloadSizeLimit(uint16 _dstChainId, uint _size) external onlyOwner {
payloadSizeLimitLookup[_dstChainId] = _size;
}
//--------------------------- VIEW FUNCTION ----------------------------------------
function isTrustedRemote(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool) {
bytes memory trustedSource = trustedRemoteLookup[_srcChainId];
return keccak256(trustedSource) == keccak256(_srcAddress);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./LzApp.sol";
import "../util/ExcessivelySafeCall.sol";
/*
* the default LayerZero messaging behaviour is blocking, i.e. any failed message will block the channel
* this abstract class try-catch all fail messages and store locally for future retry. hence, non-blocking
* NOTE: if the srcAddress is not configured properly, it will still block the message pathway from (srcChainId, srcAddress)
*/
abstract contract NonblockingLzApp is LzApp {
using ExcessivelySafeCall for address;
constructor(address _endpoint) LzApp(_endpoint) {}
mapping(uint16 => mapping(bytes => mapping(uint64 => bytes32))) public failedMessages;
event MessageFailed(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes _payload, bytes _reason);
event RetryMessageSuccess(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes32 _payloadHash);
// overriding the virtual function in LzReceiver
function _blockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual override {
(bool success, bytes memory reason) = address(this).excessivelySafeCall(gasleft(), 150, abi.encodeWithSelector(this.nonblockingLzReceive.selector, _srcChainId, _srcAddress, _nonce, _payload));
// try-catch all errors/exceptions
if (!success) {
_storeFailedMessage(_srcChainId, _srcAddress, _nonce, _payload, reason);
}
}
function _storeFailedMessage(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload, bytes memory _reason) internal virtual {
failedMessages[_srcChainId][_srcAddress][_nonce] = keccak256(_payload);
emit MessageFailed(_srcChainId, _srcAddress, _nonce, _payload, _reason);
}
function nonblockingLzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public virtual {
// only internal transaction
require(_msgSender() == address(this), "NonblockingLzApp: caller must be LzApp");
_nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
}
//@notice override this function
function _nonblockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual;
function retryMessage(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public payable virtual {
// assert there is message to retry
bytes32 payloadHash = failedMessages[_srcChainId][_srcAddress][_nonce];
require(payloadHash != bytes32(0), "NonblockingLzApp: no stored message");
require(keccak256(_payload) == payloadHash, "NonblockingLzApp: invalid payload");
// clear the stored message
failedMessages[_srcChainId][_srcAddress][_nonce] = bytes32(0);
// execute the message. revert if it fails again
_nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
emit RetryMessageSuccess(_srcChainId, _srcAddress, _nonce, payloadHash);
}
}
// SPDX-License-Identifier: Unlicense
/*
* @title Solidity Bytes Arrays Utils
* @author Gonçalo Sá <[email protected]>
*
* @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
* The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
*/
pragma solidity >=0.8.0 <0.9.0;
library BytesLib {
function concat(
bytes memory _preBytes,
bytes memory _postBytes
)
internal
pure
returns (bytes memory)
{
bytes memory tempBytes;
assembly {
// Get a location of some free memory and store it in tempBytes as
// Solidity does for memory variables.
tempBytes := mload(0x40)
// Store the length of the first bytes array at the beginning of
// the memory for tempBytes.
let length := mload(_preBytes)
mstore(tempBytes, length)
// Maintain a memory counter for the current write location in the
// temp bytes array by adding the 32 bytes for the array length to
// the starting location.
let mc := add(tempBytes, 0x20)
// Stop copying when the memory counter reaches the length of the
// first bytes array.
let end := add(mc, length)
for {
// Initialize a copy counter to the start of the _preBytes data,
// 32 bytes into its memory.
let cc := add(_preBytes, 0x20)
} lt(mc, end) {
// Increase both counters by 32 bytes each iteration.
mc := add(mc, 0x20)
cc := add(cc, 0x20)
} {
// Write the _preBytes data into the tempBytes memory 32 bytes
// at a time.
mstore(mc, mload(cc))
}
// Add the length of _postBytes to the current length of tempBytes
// and store it as the new length in the first 32 bytes of the
// tempBytes memory.
length := mload(_postBytes)
mstore(tempBytes, add(length, mload(tempBytes)))
// Move the memory counter back from a multiple of 0x20 to the
// actual end of the _preBytes data.
mc := end
// Stop copying when the memory counter reaches the new combined
// length of the arrays.
end := add(mc, length)
for {
let cc := add(_postBytes, 0x20)
} lt(mc, end) {
mc := add(mc, 0x20)
cc := add(cc, 0x20)
} {
mstore(mc, mload(cc))
}
// Update the free-memory pointer by padding our last write location
// to 32 bytes: add 31 bytes to the end of tempBytes to move to the
// next 32 byte block, then round down to the nearest multiple of
// 32. If the sum of the length of the two arrays is zero then add
// one before rounding down to leave a blank 32 bytes (the length block with 0).
mstore(0x40, and(
add(add(end, iszero(add(length, mload(_preBytes)))), 31),
not(31) // Round down to the nearest 32 bytes.
))
}
return tempBytes;
}
function concatStorage(bytes storage _preBytes, bytes memory _postBytes) internal {
assembly {
// Read the first 32 bytes of _preBytes storage, which is the length
// of the array. (We don't need to use the offset into the slot
// because arrays use the entire slot.)
let fslot := sload(_preBytes.slot)
// Arrays of 31 bytes or less have an even value in their slot,
// while longer arrays have an odd value. The actual length is
// the slot divided by two for odd values, and the lowest order
// byte divided by two for even values.
// If the slot is even, bitwise and the slot with 255 and divide by
// two to get the length. If the slot is odd, bitwise and the slot
// with -1 and divide by two.
let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
let mlength := mload(_postBytes)
let newlength := add(slength, mlength)
// slength can contain both the length and contents of the array
// if length < 32 bytes so let's prepare for that
// v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
switch add(lt(slength, 32), lt(newlength, 32))
case 2 {
// Since the new array still fits in the slot, we just need to
// update the contents of the slot.
// uint256(bytes_storage) = uint256(bytes_storage) + uint256(bytes_memory) + new_length
sstore(
_preBytes.slot,
// all the modifications to the slot are inside this
// next block
add(
// we can just add to the slot contents because the
// bytes we want to change are the LSBs
fslot,
add(
mul(
div(
// load the bytes from memory
mload(add(_postBytes, 0x20)),
// zero all bytes to the right
exp(0x100, sub(32, mlength))
),
// and now shift left the number of bytes to
// leave space for the length in the slot
exp(0x100, sub(32, newlength))
),
// increase length by the double of the memory
// bytes length
mul(mlength, 2)
)
)
)
}
case 1 {
// The stored value fits in the slot, but the combined value
// will exceed it.
// get the keccak hash to get the contents of the array
mstore(0x0, _preBytes.slot)
let sc := add(keccak256(0x0, 0x20), div(slength, 32))
// save new length
sstore(_preBytes.slot, add(mul(newlength, 2), 1))
// The contents of the _postBytes array start 32 bytes into
// the structure. Our first read should obtain the `submod`
// bytes that can fit into the unused space in the last word
// of the stored array. To get this, we read 32 bytes starting
// from `submod`, so the data we read overlaps with the array
// contents by `submod` bytes. Masking the lowest-order
// `submod` bytes allows us to add that value directly to the
// stored value.
let submod := sub(32, slength)
let mc := add(_postBytes, submod)
let end := add(_postBytes, mlength)
let mask := sub(exp(0x100, submod), 1)
sstore(
sc,
add(
and(
fslot,
0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00
),
and(mload(mc), mask)
)
)
for {
mc := add(mc, 0x20)
sc := add(sc, 1)
} lt(mc, end) {
sc := add(sc, 1)
mc := add(mc, 0x20)
} {
sstore(sc, mload(mc))
}
mask := exp(0x100, sub(mc, end))
sstore(sc, mul(div(mload(mc), mask), mask))
}
default {
// get the keccak hash to get the contents of the array
mstore(0x0, _preBytes.slot)
// Start copying to the last used word of the stored array.
let sc := add(keccak256(0x0, 0x20), div(slength, 32))
// save new length
sstore(_preBytes.slot, add(mul(newlength, 2), 1))
// Copy over the first `submod` bytes of the new data as in
// case 1 above.
let slengthmod := mod(slength, 32)
let mlengthmod := mod(mlength, 32)
let submod := sub(32, slengthmod)
let mc := add(_postBytes, submod)
let end := add(_postBytes, mlength)
let mask := sub(exp(0x100, submod), 1)
sstore(sc, add(sload(sc), and(mload(mc), mask)))
for {
sc := add(sc, 1)
mc := add(mc, 0x20)
} lt(mc, end) {
sc := add(sc, 1)
mc := add(mc, 0x20)
} {
sstore(sc, mload(mc))
}
mask := exp(0x100, sub(mc, end))
sstore(sc, mul(div(mload(mc), mask), mask))
}
}
}
function slice(
bytes memory _bytes,
uint256 _start,
uint256 _length
)
internal
pure
returns (bytes memory)
{
require(_length + 31 >= _length, "slice_overflow");
require(_bytes.length >= _start + _length, "slice_outOfBounds");
bytes memory tempBytes;
assembly {
switch iszero(_length)
case 0 {
// Get a location of some free memory and store it in tempBytes as
// Solidity does for memory variables.
tempBytes := mload(0x40)
// The first word of the slice result is potentially a partial
// word read from the original array. To read it, we calculate
// the length of that partial word and start copying that many
// bytes into the array. The first word we copy will start with
// data we don't care about, but the last `lengthmod` bytes will
// land at the beginning of the contents of the new array. When
// we're done copying, we overwrite the full first word with
// the actual length of the slice.
let lengthmod := and(_length, 31)
// The multiplication in the next line is necessary
// because when slicing multiples of 32 bytes (lengthmod == 0)
// the following copy loop was copying the origin's length
// and then ending prematurely not copying everything it should.
let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
let end := add(mc, _length)
for {
// The multiplication in the next line has the same exact purpose
// as the one above.
let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
} lt(mc, end) {
mc := add(mc, 0x20)
cc := add(cc, 0x20)
} {
mstore(mc, mload(cc))
}
mstore(tempBytes, _length)
//update free-memory pointer
//allocating the array padded to 32 bytes like the compiler does now
mstore(0x40, and(add(mc, 31), not(31)))
}
//if we want a zero-length slice let's just return a zero-length array
default {
tempBytes := mload(0x40)
//zero out the 32 bytes slice we are about to return
//we need to do it because Solidity does not garbage collect
mstore(tempBytes, 0)
mstore(0x40, add(tempBytes, 0x20))
}
}
return tempBytes;
}
function toAddress(bytes memory _bytes, uint256 _start) internal pure returns (address) {
require(_bytes.length >= _start + 20, "toAddress_outOfBounds");
address tempAddress;
assembly {
tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
}
return tempAddress;
}
function toUint8(bytes memory _bytes, uint256 _start) internal pure returns (uint8) {
require(_bytes.length >= _start + 1 , "toUint8_outOfBounds");
uint8 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x1), _start))
}
return tempUint;
}
function toUint16(bytes memory _bytes, uint256 _start) internal pure returns (uint16) {
require(_bytes.length >= _start + 2, "toUint16_outOfBounds");
uint16 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x2), _start))
}
return tempUint;
}
function toUint32(bytes memory _bytes, uint256 _start) internal pure returns (uint32) {
require(_bytes.length >= _start + 4, "toUint32_outOfBounds");
uint32 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x4), _start))
}
return tempUint;
}
function toUint64(bytes memory _bytes, uint256 _start) internal pure returns (uint64) {
require(_bytes.length >= _start + 8, "toUint64_outOfBounds");
uint64 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x8), _start))
}
return tempUint;
}
function toUint96(bytes memory _bytes, uint256 _start) internal pure returns (uint96) {
require(_bytes.length >= _start + 12, "toUint96_outOfBounds");
uint96 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0xc), _start))
}
return tempUint;
}
function toUint128(bytes memory _bytes, uint256 _start) internal pure returns (uint128) {
require(_bytes.length >= _start + 16, "toUint128_outOfBounds");
uint128 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x10), _start))
}
return tempUint;
}
function toUint256(bytes memory _bytes, uint256 _start) internal pure returns (uint256) {
require(_bytes.length >= _start + 32, "toUint256_outOfBounds");
uint256 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x20), _start))
}
return tempUint;
}
function toBytes32(bytes memory _bytes, uint256 _start) internal pure returns (bytes32) {
require(_bytes.length >= _start + 32, "toBytes32_outOfBounds");
bytes32 tempBytes32;
assembly {
tempBytes32 := mload(add(add(_bytes, 0x20), _start))
}
return tempBytes32;
}
function equal(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bool) {
bool success = true;
assembly {
let length := mload(_preBytes)
// if lengths don't match the arrays are not equal
switch eq(length, mload(_postBytes))
case 1 {
// cb is a circuit breaker in the for loop since there's
// no said feature for inline assembly loops
// cb = 1 - don't breaker
// cb = 0 - break
let cb := 1
let mc := add(_preBytes, 0x20)
let end := add(mc, length)
for {
let cc := add(_postBytes, 0x20)
// the next line is the loop condition:
// while(uint256(mc < end) + cb == 2)
} eq(add(lt(mc, end), cb), 2) {
mc := add(mc, 0x20)
cc := add(cc, 0x20)
} {
// if any of these checks fails then arrays are not equal
if iszero(eq(mload(mc), mload(cc))) {
// unsuccess:
success := 0
cb := 0
}
}
}
default {
// unsuccess:
success := 0
}
}
return success;
}
function equalStorage(
bytes storage _preBytes,
bytes memory _postBytes
)
internal
view
returns (bool)
{
bool success = true;
assembly {
// we know _preBytes_offset is 0
let fslot := sload(_preBytes.slot)
// Decode the length of the stored array like in concatStorage().
let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
let mlength := mload(_postBytes)
// if lengths don't match the arrays are not equal
switch eq(slength, mlength)
case 1 {
// slength can contain both the length and contents of the array
// if length < 32 bytes so let's prepare for that
// v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
if iszero(iszero(slength)) {
switch lt(slength, 32)
case 1 {
// blank the last byte which is the length
fslot := mul(div(fslot, 0x100), 0x100)
if iszero(eq(fslot, mload(add(_postBytes, 0x20)))) {
// unsuccess:
success := 0
}
}
default {
// cb is a circuit breaker in the for loop since there's
// no said feature for inline assembly loops
// cb = 1 - don't breaker
// cb = 0 - break
let cb := 1
// get the keccak hash to get the contents of the array
mstore(0x0, _preBytes.slot)
let sc := keccak256(0x0, 0x20)
let mc := add(_postBytes, 0x20)
let end := add(mc, mlength)
// the next line is the loop condition:
// while(uint256(mc < end) + cb == 2)
for {} eq(add(lt(mc, end), cb), 2) {
sc := add(sc, 1)
mc := add(mc, 0x20)
} {
if iszero(eq(sload(sc), mload(mc))) {
// unsuccess:
success := 0
cb := 0
}
}
}
}
}
default {
// unsuccess:
success := 0
}
}
return success;
}
}
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity >=0.7.6;
library ExcessivelySafeCall {
uint256 constant LOW_28_MASK =
0x00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
/// @notice Use when you _really_ really _really_ don't trust the called
/// contract. This prevents the called contract from causing reversion of
/// the caller in as many ways as we can.
/// @dev The main difference between this and a solidity low-level call is
/// that we limit the number of bytes that the callee can cause to be
/// copied to caller memory. This prevents stupid things like malicious
/// contracts returning 10,000,000 bytes causing a local OOG when copying
/// to memory.
/// @param _target The address to call
/// @param _gas The amount of gas to forward to the remote contract
/// @param _maxCopy The maximum number of bytes of returndata to copy
/// to memory.
/// @param _calldata The data to send to the remote contract
/// @return success and returndata, as `.call()`. Returndata is capped to
/// `_maxCopy` bytes.
function excessivelySafeCall(
address _target,
uint256 _gas,
uint16 _maxCopy,
bytes memory _calldata
) internal returns (bool, bytes memory) {
// set up for assembly call
uint256 _toCopy;
bool _success;
bytes memory _returnData = new bytes(_maxCopy);
// dispatch message to recipient
// by assembly calling "handle" function
// we call via assembly to avoid memcopying a very large returndata
// returned by a malicious contract
assembly {
_success := call(
_gas, // gas
_target, // recipient
0, // ether value
add(_calldata, 0x20), // inloc
mload(_calldata), // inlen
0, // outloc
0 // outlen
)
// limit our copy to 256 bytes
_toCopy := returndatasize()
if gt(_toCopy, _maxCopy) {
_toCopy := _maxCopy
}
// Store the length of the copied bytes
mstore(_returnData, _toCopy)
// copy the bytes from returndata[0:_toCopy]
returndatacopy(add(_returnData, 0x20), 0, _toCopy)
}
return (_success, _returnData);
}
/// @notice Use when you _really_ really _really_ don't trust the called
/// contract. This prevents the called contract from causing reversion of
/// the caller in as many ways as we can.
/// @dev The main difference between this and a solidity low-level call is
/// that we limit the number of bytes that the callee can cause to be
/// copied to caller memory. This prevents stupid things like malicious
/// contracts returning 10,000,000 bytes causing a local OOG when copying
/// to memory.
/// @param _target The address to call
/// @param _gas The amount of gas to forward to the remote contract
/// @param _maxCopy The maximum number of bytes of returndata to copy
/// to memory.
/// @param _calldata The data to send to the remote contract
/// @return success and returndata, as `.call()`. Returndata is capped to
/// `_maxCopy` bytes.
function excessivelySafeStaticCall(
address _target,
uint256 _gas,
uint16 _maxCopy,
bytes memory _calldata
) internal view returns (bool, bytes memory) {
// set up for assembly call
uint256 _toCopy;
bool _success;
bytes memory _returnData = new bytes(_maxCopy);
// dispatch message to recipient
// by assembly calling "handle" function
// we call via assembly to avoid memcopying a very large returndata
// returned by a malicious contract
assembly {
_success := staticcall(
_gas, // gas
_target, // recipient
add(_calldata, 0x20), // inloc
mload(_calldata), // inlen
0, // outloc
0 // outlen
)
// limit our copy to 256 bytes
_toCopy := returndatasize()
if gt(_toCopy, _maxCopy) {
_toCopy := _maxCopy
}
// Store the length of the copied bytes
mstore(_returnData, _toCopy)
// copy the bytes from returndata[0:_toCopy]
returndatacopy(add(_returnData, 0x20), 0, _toCopy)
}
return (_success, _returnData);
}
/**
* @notice Swaps function selectors in encoded contract calls
* @dev Allows reuse of encoded calldata for functions with identical
* argument types but different names. It simply swaps out the first 4 bytes
* for the new selector. This function modifies memory in place, and should
* only be used with caution.
* @param _newSelector The new 4-byte selector
* @param _buf The encoded contract args
*/
function swapSelector(bytes4 _newSelector, bytes memory _buf)
internal
pure
{
require(_buf.length >= 4);
uint256 _mask = LOW_28_MASK;
assembly {
// load the first word of
let _word := mload(add(_buf, 0x20))
// mask out the top 4 bytes
// /x
_word := and(_word, _mask)
_word := or(_newSelector, _word)
mstore(add(_buf, 0x20), _word)
}
}
}
// 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 v4.4.1 (interfaces/IERC20.sol)
pragma solidity ^0.8.0;
import "../token/ERC20/IERC20.sol";
// 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 (last updated v4.9.0) (token/ERC20/ERC20.sol)
pragma solidity ^0.8.0;
import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* The default value of {decimals} is 18. To change this, you should override
* this function so it returns a different value.
*
* We have followed general OpenZeppelin Contracts guidelines: functions revert
* instead returning `false` on failure. This behavior is nonetheless
* conventional and does not conflict with the expectations of ERC20
* applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
contract ERC20 is Context, IERC20, IERC20Metadata {
mapping(address => uint256) private _balances;
mapping(address => mapping(address => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
/**
* @dev Sets the values for {name} and {symbol}.
*
* All two of these values are immutable: they can only be set once during
* construction.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5.05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the default value returned by this function, unless
* it's overridden.
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view virtual override returns (uint8) {
return 18;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view virtual override returns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address to, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_transfer(owner, to, amount);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public view virtual override returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
* `transferFrom`. This is semantically equivalent to an infinite approval.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_approve(owner, spender, amount);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* NOTE: Does not update the allowance if the current allowance
* is the maximum `uint256`.
*
* Requirements:
*
* - `from` and `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
* - the caller must have allowance for ``from``'s tokens of at least
* `amount`.
*/
function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
address spender = _msgSender();
_spendAllowance(from, spender, amount);
_transfer(from, to, amount);
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
address owner = _msgSender();
_approve(owner, spender, allowance(owner, spender) + addedValue);
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
address owner = _msgSender();
uint256 currentAllowance = allowance(owner, spender);
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(owner, spender, currentAllowance - subtractedValue);
}
return true;
}
/**
* @dev Moves `amount` of tokens from `from` to `to`.
*
* This internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
*/
function _transfer(address from, address to, uint256 amount) internal virtual {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(from, to, amount);
uint256 fromBalance = _balances[from];
require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[from] = fromBalance - amount;
// Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
// decrementing then incrementing.
_balances[to] += amount;
}
emit Transfer(from, to, amount);
_afterTokenTransfer(from, to, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), account, amount);
_totalSupply += amount;
unchecked {
// Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
_balances[account] += amount;
}
emit Transfer(address(0), account, amount);
_afterTokenTransfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(account, address(0), amount);
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
unchecked {
_balances[account] = accountBalance - amount;
// Overflow not possible: amount <= accountBalance <= totalSupply.
_totalSupply -= amount;
}
emit Transfer(account, address(0), amount);
_afterTokenTransfer(account, address(0), amount);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(address owner, address spender, uint256 amount) internal virtual {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
/**
* @dev Updates `owner` s allowance for `spender` based on spent `amount`.
*
* Does not update the allowance amount in case of infinite allowance.
* Revert if not enough allowance is available.
*
* Might emit an {Approval} event.
*/
function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
uint256 currentAllowance = allowance(owner, spender);
if (currentAllowance != type(uint256).max) {
require(currentAllowance >= amount, "ERC20: insufficient allowance");
unchecked {
_approve(owner, spender, currentAllowance - amount);
}
}
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* will be transferred to `to`.
* - when `from` is zero, `amount` tokens will be minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}
/**
* @dev Hook that is called after any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* has been transferred to `to`.
* - when `from` is zero, `amount` tokens have been minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens have been burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol)
pragma solidity ^0.8.0;
import "../ERC20.sol";
import "../../../utils/Context.sol";
/**
* @dev Extension of {ERC20} that allows token holders to destroy both their own
* tokens and those that they have an allowance for, in a way that can be
* recognized off-chain (via event analysis).
*/
abstract contract ERC20Burnable is Context, ERC20 {
/**
* @dev Destroys `amount` tokens from the caller.
*
* See {ERC20-_burn}.
*/
function burn(uint256 amount) public virtual {
_burn(_msgSender(), amount);
}
/**
* @dev Destroys `amount` tokens from `account`, deducting from the caller's
* allowance.
*
* See {ERC20-_burn} and {ERC20-allowance}.
*
* Requirements:
*
* - the caller must have allowance for ``accounts``'s tokens of at least
* `amount`.
*/
function burnFrom(address account, uint256 amount) public virtual {
_spendAllowance(account, _msgSender(), amount);
_burn(account, amount);
}
}
// 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 v4.9.4) (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.
*
* ==== Security Considerations
*
* There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
* expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
* considered as an intention to spend the allowance in any specific way. The second is that because permits have
* built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
* take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
* generally recommended is:
*
* ```solidity
* function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
* try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
* doThing(..., value);
* }
*
* function doThing(..., uint256 value) public {
* token.safeTransferFrom(msg.sender, address(this), value);
* ...
* }
* ```
*
* Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
* `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
* {SafeERC20-safeTransferFrom}).
*
* Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
* contracts should have entry points that don't rely on permit.
*/
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].
*
* CAUTION: See Security Considerations above.
*/
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 (last updated v4.9.4) (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;
}
function _contextSuffixLength() internal view virtual returns (uint256) {
return 0;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/SafeMath.sol)
pragma solidity ^0.8.0;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
* @dev Wrappers over Solidity's arithmetic operations.
*
* NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
* now has built in overflow checking.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the subtraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b > a) return (false, 0);
return (true, a - b);
}
}
/**
* @dev Returns the multiplication of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the division of two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a / b);
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a % b);
}
}
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
return a + b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return a - b;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
return a * b;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator.
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return a % b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {trySub}.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b <= a, errorMessage);
return a - b;
}
}
/**
* @dev Returns the integer division of two unsigned integers, reverting with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a / b;
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting with custom message when dividing by zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryMod}.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a % b;
}
}
}
// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.6.0;
// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
library TransferHelper {
function safeApprove(
address token,
address to,
uint256 value
) internal {
// bytes4(keccak256(bytes('approve(address,uint256)')));
(bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
require(
success && (data.length == 0 || abi.decode(data, (bool))),
'TransferHelper::safeApprove: approve failed'
);
}
function safeTransfer(
address token,
address to,
uint256 value
) internal {
// bytes4(keccak256(bytes('transfer(address,uint256)')));
(bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
require(
success && (data.length == 0 || abi.decode(data, (bool))),
'TransferHelper::safeTransfer: transfer failed'
);
}
function safeTransferFrom(
address token,
address from,
address to,
uint256 value
) internal {
// bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
(bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
require(
success && (data.length == 0 || abi.decode(data, (bool))),
'TransferHelper::transferFrom: transferFrom failed'
);
}
function safeTransferETH(address to, uint256 value) internal {
(bool success, ) = to.call{value: value}(new bytes(0));
require(success, 'TransferHelper::safeTransferETH: ETH transfer failed');
}
}
pragma solidity >=0.5.0;
interface IUniswapV2Factory {
event PairCreated(address indexed token0, address indexed token1, address pair, uint);
function feeTo() external view returns (address);
function feeToSetter() external view returns (address);
function getPair(address tokenA, address tokenB) external view returns (address pair);
function allPairs(uint) external view returns (address pair);
function allPairsLength() external view returns (uint);
function createPair(address tokenA, address tokenB) external returns (address pair);
function setFeeTo(address) external;
function setFeeToSetter(address) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;
import "@openzeppelin/contracts/interfaces/IERC20.sol";
import "@openzeppelin/contracts/security/Pausable.sol";
import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol';
import '@uniswap/lib/contracts/libraries/TransferHelper.sol';
import '@layerzerolabs/solidity-examples/contracts/lzApp/NonblockingLzApp.sol';
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import { OApp, Origin, MessagingFee } from "@layerzerolabs/oapp-evm/contracts/oapp/OApp.sol";
import '@layerzerolabs/lz-evm-protocol-v2/contracts/interfaces/ILayerZeroEndpointV2.sol';
import "@openzeppelin/contracts/access/Ownable.sol";
import "./BToken.sol";
import "./interfaces/IWeth.sol";
struct BridgeToken
{
bool isEnabled;
address tokenAddress;
bool isMintable;
uint256 destChainAmount;
}
struct RecieveToken
{
bool isEnabled;
address tokenAddress;
bool isMintable;
}
contract BridgeV2 is Ownable, Pausable,ReentrancyGuard,OApp{
mapping(address => BridgeToken) public bridgeTokens; //Allowed tokens to bridge
address[] tokenBridgeKeys;
mapping(address => RecieveToken) public recieveTokens; //Allowed tokens to recieve
address[] tokenRecieveKeys;
uint32 public dstId;
uint public feeTeamPercent; //Percent which goes to team
uint public feeDevPercent; // Percent which goes to devs
address public teamPool; //Team pool
address public devPool; //Dev pool
event FeePercentSet(uint _feeTeam, uint _feeDevs);
event DestEndpointSet(uint endpointId);
event BridgeTokenSet(address tokenAddress);
event BridgeTokenAmountUpdated(address tokenAddress,uint256 amount);
event Bridged(uint256 amount, address recieverAddress, address tokenAddress);
event Recieved(address tokenAddress,address reciever,uint256 amount,uint srcChainId);
constructor(address _endpoint) OApp(_endpoint,msg.sender){
require(_endpoint != address(0));
pause();
}
function getBridgeTokens() public view returns (BridgeToken[] memory) {
BridgeToken[] memory result = new BridgeToken[](tokenBridgeKeys.length);
for (uint i = 0; i < tokenBridgeKeys.length; i++) {
result[i] = bridgeTokens[tokenBridgeKeys[i]];
}
return result;
}
function getRecieveTokens() public view returns (RecieveToken[] memory) {
RecieveToken[] memory result = new RecieveToken[](tokenRecieveKeys.length);
for (uint i = 0; i < tokenRecieveKeys.length; i++) {
result[i] = recieveTokens[tokenRecieveKeys[i]];
}
return result;
}
function setupTeamDevPool(address _teamPool,address _devPool) external onlyOwner
{
require(_teamPool != address(0));
require(_devPool != address(0));
teamPool = _teamPool;
devPool = _devPool;
}
function setupFeePercent(uint _feeTeamPercent, uint _feeDevPercent) external onlyOwner
{
require(_feeDevPercent + _feeTeamPercent <= 100);
feeTeamPercent = _feeTeamPercent;
feeDevPercent = _feeDevPercent;
emit FeePercentSet(feeTeamPercent,feeDevPercent);
}
function setupRecieveToken(address _onChainTokenAddress, address _recieveTokenAddress,bool _isMintable) external onlyOwner
{
require(_onChainTokenAddress != address(0),
"Invalid token address");
require(_recieveTokenAddress != address(0),
"Invalid source token address");
require(bridgeTokens[_onChainTokenAddress].isEnabled == true,
"Setup bridge token first");
require(recieveTokens[_recieveTokenAddress].isEnabled == false,
"Token already inited");
recieveTokens[_recieveTokenAddress].isEnabled = true;
recieveTokens[_recieveTokenAddress].isMintable = _isMintable;
recieveTokens[_recieveTokenAddress].tokenAddress = _onChainTokenAddress;
if(recieveTokens[_recieveTokenAddress].isMintable == true)
{
require(BToken(_onChainTokenAddress).operator() == address(this),"Bridge is not mint operator");
require(BToken(_onChainTokenAddress).owner() == address(0),"Owner not renounced");
}
tokenRecieveKeys.push(_recieveTokenAddress);
}
function setupBridgeToken(address _tokenAddress, bool _isMintable,uint256 _destTokenInBridgeAmount) external onlyOwner
{
require(_tokenAddress != address(0),
"Invalid token address");
// require(bridgeTokens[_tokenAddress].isEnabled == false,
// "Token already setuped");
if(bridgeTokens[_tokenAddress].isEnabled == true)
{
//Extra utility for users to add more nonmintable tokens to bridge endpoint
require(_destTokenInBridgeAmount > bridgeTokens[_tokenAddress].destChainAmount);
bridgeTokens[_tokenAddress].destChainAmount = _destTokenInBridgeAmount;
emit BridgeTokenAmountUpdated(_tokenAddress,_destTokenInBridgeAmount);
return;
}
bridgeTokens[_tokenAddress].isMintable = _isMintable;
bridgeTokens[_tokenAddress].tokenAddress = _tokenAddress;
bridgeTokens[_tokenAddress].isEnabled = true;
bridgeTokens[_tokenAddress].destChainAmount = _destTokenInBridgeAmount;
tokenBridgeKeys.push(_tokenAddress);
emit BridgeTokenSet(_tokenAddress);
}
function setupDestChainParam(uint32 _chainId) external onlyOwner
{
require(_chainId != 0,
"Invalid chain ID");
require(dstId == 0,
"Chain param already setuped");
dstId = _chainId;
emit DestEndpointSet(_chainId);
}
function estimateTransferFees(uint32 _destChainId,address _recieverAddress,
address _tokenAddress,
uint256 _amount,bytes calldata _options) public view returns (uint256,uint256,uint256)
{
require(bridgeTokens[_tokenAddress].isEnabled == true,
"Token is not allowed");
require(_destChainId == dstId,
"Chain is not allowed");
bytes memory payload = abi.encode(_tokenAddress,_recieverAddress, _amount);
MessagingFee memory layerZeroFee = _quote(_destChainId,
payload,_options,false) ;
uint256 feeTeam = 0;
uint256 feeDev = 0;
if(feeDevPercent > 0)
{
feeDev = (_amount / 10000) * feeDevPercent;
}
if(feeTeamPercent > 0)
{
feeTeam = (_amount / 10000) * feeTeamPercent;
}
return(layerZeroFee.nativeFee,feeTeam,feeDev);
}
function bridge( uint32 _dstChainId,address _recieverAddress,
address _tokenAddress, uint256 _amount, bytes calldata _options) external payable whenNotPaused nonReentrant
{
require(bridgeTokens[_tokenAddress].isEnabled == true,
"Token is not allowed");
require(_dstChainId == dstId,
"Chain is not allowed");
require(_amount > 0,
"Invalid amount");
(uint256 layerZeroFee,uint256 feeTeamAmount,uint256 feeDevAmount) = estimateTransferFees(_dstChainId,
_recieverAddress,
_tokenAddress,
_amount,
_options);
require(msg.value >= layerZeroFee,
"Insufficient NATIVE fee");
_amount = _amount - (feeTeamAmount + feeDevAmount);
if(bridgeTokens[_tokenAddress].isMintable == false)
{
require( bridgeTokens[_tokenAddress].destChainAmount >=_amount,
"Insufficient Dest token amount");
bridgeTokens[_tokenAddress].destChainAmount -= _amount;
}
uint256 balbefore = 0;
if(feeTeamAmount > 0)
{
balbefore = IERC20(_tokenAddress).balanceOf(
teamPool);
TransferHelper.safeTransferFrom(_tokenAddress,
msg.sender, teamPool, feeTeamAmount);
require(balbefore + feeTeamAmount
== IERC20(_tokenAddress).balanceOf(teamPool),
"Invalid transfer, may be token fee" );
}
if(feeDevAmount > 0)
{
balbefore = IERC20(_tokenAddress).balanceOf(
devPool);
TransferHelper.safeTransferFrom(_tokenAddress, msg.sender, devPool, feeDevAmount);
require(balbefore + feeDevAmount
== IERC20(_tokenAddress).balanceOf(devPool),
"Invalid transfer, may be token fee" );
}
balbefore = IERC20(_tokenAddress).balanceOf(
address(this));
TransferHelper.safeTransferFrom(_tokenAddress, msg.sender, address(this), _amount );
require(balbefore + _amount
== IERC20(_tokenAddress).balanceOf(address(this)),
"Invalid transfer, may be token fee" );
bytes memory payload = abi.encode(_tokenAddress,_recieverAddress, _amount);
_lzSend(_dstChainId,
payload,
_options,
MessagingFee(msg.value,0),
payable(msg.sender));
emit Bridged(_amount,_recieverAddress,_tokenAddress);
}
function _lzReceive(
Origin calldata _origin,
bytes32 _guid,
bytes calldata _payload,
address,
bytes calldata
) internal override {
(address token,address reciever, uint amount) = abi.decode(_payload, (address ,address , uint));
require(recieveTokens[token].isEnabled,"Token Not enabled");
require(_origin.srcEid == dstId,"Invalid chain sender");
bridgeTokens[recieveTokens[token].tokenAddress].destChainAmount += amount;
if(recieveTokens[token].isMintable == true &&
IERC20(recieveTokens[token].tokenAddress).balanceOf(
address(this)) < amount)
{
uint256 amountToMint = amount - IERC20(recieveTokens[token].tokenAddress).balanceOf(address(this));
if(amountToMint != amount)
{
IERC20(recieveTokens[token].tokenAddress).transfer(reciever,amount - amountToMint);
}
BToken(recieveTokens[token].tokenAddress).mint(reciever,amountToMint);
emit Recieved(address(recieveTokens[token].tokenAddress), reciever, amount, dstId);
return;
}
require(IERC20(recieveTokens[token].tokenAddress).balanceOf(address(this)) >= amount,
"Insufficient balance, try again later");
IERC20(recieveTokens[token].tokenAddress).transfer(reciever,amount);
emit Recieved(address(recieveTokens[token].tokenAddress), reciever, amount, dstId);
}
function pause() public onlyOwner
{
super._pause();
}
function unpause() public onlyOwner
{
super._unpause();
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/token/ERC20/extensions/ERC20Burnable.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "./owner/Operator.sol";
contract BToken is ERC20Burnable, Operator {
using SafeMath for uint256;
constructor(string memory name_, string memory symbol_) ERC20(name_, symbol_) {
}
function mint(address recipient_, uint256 amount_) public onlyOperator returns (bool) {
_mint(recipient_, amount_);
return true;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IWETH {
function deposit() external payable;
function transfer(address to, uint value) external returns (bool);
function withdraw(uint) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
contract Operator is Context, Ownable {
address private _operator;
event OperatorTransferred(address indexed previousOperator, address indexed newOperator);
constructor() {
_operator = _msgSender();
emit OperatorTransferred(address(0), _operator);
}
function operator() public view returns (address) {
return _operator;
}
modifier onlyOperator() {
require(_operator == msg.sender, "operator: caller is not the operator");
_;
}
function isOperator() public view returns (bool) {
return _msgSender() == _operator;
}
function transferOperator(address newOperator_) public onlyOwner {
_transferOperator(newOperator_);
}
function _transferOperator(address newOperator_) internal {
require(newOperator_ != address(0), "operator: zero address given for new operator");
emit OperatorTransferred(address(0), newOperator_);
_operator = newOperator_;
}
function _renounceOperator() public onlyOwner {
emit OperatorTransferred(_operator, address(0));
_operator = address(0);
}
}