CCTPBridge

Inherits: BaseBridge, CCTPHelper, IBridge, ReentrancyGuard

Title: CCTPBridge

Author: Malda Protocol

Cross-chain bridge that uses Circle CCTP v2

State Variables

REBALANCER

The Rebalancer contract allowed to initiate bridging actions.

address public immutable REBALANCER

chainIdToDomain

Maps EVM chainId -> CCTP domain id.

mapping(uint32 chainId => uint32 cctpDomain) public chainIdToDomain

domainSet

Tracks whether a domain mapping exists for a given EVM chainId.

mapping(uint32 chainId => bool isSet) public domainSet

Functions

constructor

Constructor for the CCTPBridge contract.

constructor(address _roles, address _tokenMessenger, address _messageTransmitter, address _rebalancer)
    BaseBridge(_roles)
    CCTPHelper(_tokenMessenger, _messageTransmitter);

Parameters

Name	Type	Description
`_roles`	`address`	Address of the Roles contract.
`_tokenMessenger`	`address`	Address of the TokenMessenger contract.
`_messageTransmitter`	`address`	Address of the MessageTransmitter contract.
`_rebalancer`	`address`	Address of the Rebalancer contract.

setDomainMapping

Sets the CCTP domain id for a given EVM chainId.

function setDomainMapping(uint32 chainId, uint32 domain) external onlyBridgeConfigurator;

Parameters

Name	Type	Description
`chainId`	`uint32`	The EVM chainId to set.
`domain`	`uint32`	The corresponding CCTP domain id.

setAcceptedToken

Enables or disables a token for use with CCTP burns.

function setAcceptedToken(address token, bool allowed) external onlyBridgeConfigurator;

Parameters

Name	Type	Description
`token`	`address`	The token address.
`allowed`	`bool`	True to enable, false to disable.

sendMsg

Burns tokens and creates a CCTP message for the destination chain.

function sendMsg(
    uint256 _extractedAmount,
    address _market,
    uint32 _dstChainId,
    address _token,
    bytes calldata _unused1,
    bytes calldata _unused2
) external payable override onlyRebalancer;

Parameters

Name	Type	Description
`_extractedAmount`	`uint256`	Amount to burn.
`_market`	`address`	Destination market address (encoded into the CCTP hook payload).
`_dstChainId`	`uint32`	Destination EVM chainId.
`_token`	`address`	Token to burn (e.g., USDC).
`_unused1`	`bytes`	Unused parameter kept for IBridge compatibility.
`_unused2`	`bytes`	Unused parameter kept for IBridge compatibility.

handleCCTPMessage

Receives a CCTP message+attestation and forwards received tokens to the encoded destination market.

function handleCCTPMessage(bytes calldata cctpMessage, bytes calldata attestation) external nonReentrant;

Parameters

Name	Type	Description
`cctpMessage`	`bytes`	Raw CCTP message bytes.
`attestation`	`bytes`	Circle attestation proving message validity.

getFee

computes fee for bridge operation

function getFee(uint32, bytes calldata, bytes calldata) external pure override returns (uint256);

Parameters

Name	Type	Description
`<none>`	`uint32`
`<none>`	`bytes`
`<none>`	`bytes`

Returns

Name	Type	Description
`<none>`	`uint256`	fee Computed bridge fee

Events

Rebalanced

Emitted when bridged funds are forwarded to a destination market.

event Rebalanced(address indexed market, uint256 amount);

Parameters

Name	Type	Description
`market`	`address`	The destination market that received the funds.
`amount`	`uint256`	The amount of tokens forwarded to the market.

DomainMappingUpdated

Emitted when a chainId -> CCTP domain mapping is updated.

event DomainMappingUpdated(uint32 indexed chainId, uint32 indexed domain);

Parameters

Name	Type	Description
`chainId`	`uint32`	The EVM chainId.
`domain`	`uint32`	The CCTP domain id.

TokenAccepted

Emitted when a token is enabled or disabled for CCTP burns.

event TokenAccepted(address indexed token, bool status);

Parameters

Name	Type	Description
`token`	`address`	The token address.
`status`	`bool`	True if enabled, false if disabled.

Errors

CCTPBridge_AddressNotValid

error CCTPBridge_AddressNotValid();

CCTPBridge_InvalidReceiver

error CCTPBridge_InvalidReceiver();

CCTPBridge_TokenMismatch

error CCTPBridge_TokenMismatch();

CCTPBridge_NotImplemented

error CCTPBridge_NotImplemented();

CCTPBridge_DomainNotSet

error CCTPBridge_DomainNotSet();