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CrossChainBridge

Git Source

Inherits: Policy, RolesConsumer, ILayerZeroReceiver, ILayerZeroUserApplicationConfig

Message bridge for cross-chain OHM transfers.

Uses LayerZero as communication protocol.

Each chain needs to setTrustedRemoteAddress for each remote address it intends to receive from.

State Variables​

MINTR​

MINTRv1 public MINTR;

lzEndpoint​

ILayerZeroEndpoint public immutable lzEndpoint;

ohm​

ERC20 public ohm;

bridgeActive​

Flag to determine if bridge is allowed to send messages or not

bool public bridgeActive;

failedMessages​

Storage for failed messages on receive.

chainID => source address => endpoint nonce

mapping(uint16 => mapping(bytes => mapping(uint64 => bytes32))) public failedMessages;

trustedRemoteLookup​

Trusted remote paths. Must be set by admin.

mapping(uint16 => bytes) public trustedRemoteLookup;

precrime​

LZ precrime address. Currently unused.

address public precrime;

Functions​

constructor​

constructor(Kernel kernel_, address endpoint_) Policy(kernel_);

configureDependencies​

Define module dependencies for this policy.

function configureDependencies() external override returns (Keycode[] memory dependencies);

Returns

NameTypeDescription
dependenciesKeycode[]- Keycode array of module dependencies.

requestPermissions​

Function called by kernel to set module function permissions.

function requestPermissions() external view override returns (Permissions[] memory permissions);

Returns

NameTypeDescription
permissionsPermissions[]requests - Array of keycodes and function selectors for requested permissions.

sendOhm​

Send OHM to an eligible chain

function sendOhm(uint16 dstChainId_, address to_, uint256 amount_) external payable;

_receiveMessage​

Implementation of receiving an LZ message

Function must be public to be called by low-level call in lzReceive

function _receiveMessage(uint16 srcChainId_, bytes memory, uint64, bytes memory payload_) internal;

lzReceive​

function lzReceive(uint16 srcChainId_, bytes calldata srcAddress_, uint64 nonce_, bytes calldata payload_)
    public
    virtual
    override;

receiveMessage​

Implementation of receiving an LZ message

Function must be public to be called by low-level call in lzReceive

function receiveMessage(uint16 srcChainId_, bytes memory srcAddress_, uint64 nonce_, bytes memory payload_) public;

retryMessage​

Retry a failed receive message

function retryMessage(uint16 srcChainId_, bytes calldata srcAddress_, uint64 nonce_, bytes calldata payload_)
    public
    payable
    virtual;

_sendMessage​

Internal function for sending a message across chains.

Params defined in ILayerZeroEndpoint send function.

function _sendMessage(
    uint16 dstChainId_,
    bytes memory payload_,
    address payable refundAddress_,
    address zroPaymentAddress_,
    bytes memory adapterParams_,
    uint256 nativeFee_
) internal;

estimateSendFee​

Function to estimate how much gas is needed to send OHM

Should be called by frontend before making sendOhm call.

function estimateSendFee(uint16 dstChainId_, address to_, uint256 amount_, bytes calldata adapterParams_)
    external
    view
    returns (uint256 nativeFee, uint256 zroFee);

Returns

NameTypeDescription
nativeFeeuint256- Native token amount to send to sendOhm
zroFeeuint256- Fee paid in ZRO token. Unused.

setConfig​

Generic config for LayerZero User Application

function setConfig(uint16 version_, uint16 chainId_, uint256 configType_, bytes calldata config_)
    external
    override
    onlyRole("bridge_admin");

setSendVersion​

Set send version of endpoint to be used by LayerZero User Application

function setSendVersion(uint16 version_) external override onlyRole("bridge_admin");

setReceiveVersion​

Set receive version of endpoint to be used by LayerZero User Application

function setReceiveVersion(uint16 version_) external override onlyRole("bridge_admin");

forceResumeReceive​

Retries a received message. Used as last resort if retryPayload fails.

Unblocks queue and DESTROYS transaction forever. USE WITH CAUTION.

function forceResumeReceive(uint16 srcChainId_, bytes calldata srcAddress_)
    external
    override
    onlyRole("bridge_admin");

setTrustedRemote​

Sets the trusted path for the cross-chain communication

path_ = abi.encodePacked(remoteAddress, localAddress)

function setTrustedRemote(uint16 srcChainId_, bytes calldata path_) external onlyRole("bridge_admin");

setTrustedRemoteAddress​

Convenience function for setting trusted paths between EVM addresses

function setTrustedRemoteAddress(uint16 remoteChainId_, bytes calldata remoteAddress_)
    external
    onlyRole("bridge_admin");

setPrecrime​

Sets precrime address

function setPrecrime(address precrime_) external onlyRole("bridge_admin");

setBridgeStatus​

Activate or deactivate the bridge

function setBridgeStatus(bool isActive_) external onlyRole("bridge_admin");

getConfig​

Gets endpoint config for this contract

function getConfig(uint16 version_, uint16 chainId_, address, uint256 configType_)
    external
    view
    returns (bytes memory);

getTrustedRemoteAddress​

Get trusted remote for the given chain as an

function getTrustedRemoteAddress(uint16 remoteChainId_) external view returns (bytes memory);

isTrustedRemote​

function isTrustedRemote(uint16 srcChainId_, bytes calldata srcAddress_) external view returns (bool);

Events​

BridgeTransferred​

event BridgeTransferred(address indexed sender_, uint256 amount_, uint16 indexed dstChain_);

BridgeReceived​

event BridgeReceived(address indexed receiver_, uint256 amount_, uint16 indexed srcChain_);

MessageFailed​

event MessageFailed(uint16 srcChainId_, bytes srcAddress_, uint64 nonce_, bytes payload_, bytes reason_);

RetryMessageSuccess​

event RetryMessageSuccess(uint16 srcChainId_, bytes srcAddress_, uint64 nonce_, bytes32 payloadHash_);

SetPrecrime​

event SetPrecrime(address precrime_);

SetTrustedRemote​

event SetTrustedRemote(uint16 remoteChainId_, bytes path_);

SetTrustedRemoteAddress​

event SetTrustedRemoteAddress(uint16 remoteChainId_, bytes remoteAddress_);

SetMinDstGas​

event SetMinDstGas(uint16 dstChainId_, uint16 type_, uint256 _minDstGas);

BridgeStatusSet​

event BridgeStatusSet(bool isActive_);

Errors​

Bridge_InsufficientAmount​

error Bridge_InsufficientAmount();

Bridge_InvalidCaller​

error Bridge_InvalidCaller();

Bridge_InvalidMessageSource​

error Bridge_InvalidMessageSource();

Bridge_NoStoredMessage​

error Bridge_NoStoredMessage();

Bridge_InvalidPayload​

error Bridge_InvalidPayload();

Bridge_DestinationNotTrusted​

error Bridge_DestinationNotTrusted();

Bridge_NoTrustedPath​

error Bridge_NoTrustedPath();

Bridge_Deactivated​

error Bridge_Deactivated();

Bridge_TrustedRemoteUninitialized​

error Bridge_TrustedRemoteUninitialized();