mErc20Host

Inherits: mErc20Upgradable, ImErc20Host, ImTokenOperationTypes

Title: mErc20Host

Author: Merge Layers Inc.

Host contract for mErc20 tokens

State Variables

acc

Mapping of chain IDs to accumulated amounts

mapping(uint32 chainId => Accumulated accumulated) internal acc

allowedCallers

Mapping of allowed callers

mapping(address caller => mapping(address target => bool allowed)) public allowedCallers

allowedChains

Mapping of allowed chains

mapping(uint32 chainId => bool allowed) public allowedChains

verifier

The ZkVerifier contract

IZkVerifier public verifier

gasHelper

The gas fees helper contract

IGasFeesHelper public gasHelper

migrator

Migrator address

address public migrator

__gap

uint256[50] private __gap

Functions

onlyMigrator

Modifier to restrict access to migrator only

modifier onlyMigrator() ;

initialize

Initializes the new money market

function initialize(
    address underlying_,
    address operator_,
    address interestRateModel_,
    uint256 initialExchangeRateMantissa_,
    // note: these have to remain as 'memory' to avoid stack-depth issues
    string memory name_,
    string memory symbol_,
    uint8 decimals_,
    address payable admin_,
    address zkVerifier_,
    address roles_
) external initializer;

Parameters

Name	Type	Description
`underlying_`	`address`	The address of the underlying asset
`operator_`	`address`	The address of the Operator
`interestRateModel_`	`address`	The address of the interest rate model
`initialExchangeRateMantissa_`	`uint256`	The initial exchange rate, scaled by 1e18
`name_`	`string`	ERC-20 name of this token
`symbol_`	`string`	ERC-20 symbol of this token
`decimals_`	`uint8`	ERC-20 decimal precision of this token
`admin_`	`address payable`	Address of the administrator of this token
`zkVerifier_`	`address`	The IZkVerifier address
`roles_`	`address`	The IRoles address

updateAllowedChain

Updates an allowed chain status

function updateAllowedChain(uint32 _chainId, bool status_) external;

Parameters

Name	Type	Description
`_chainId`	`uint32`	the chain id
`status_`	`bool`	the new status

extractForRebalancing

Extract amount to be used for rebalancing operation

function extractForRebalancing(uint256 amount) external;

Parameters

Name	Type	Description
`amount`	`uint256`	The amount to rebalance

setMigrator

Sets the migrator address

function setMigrator(address _migrator) external onlyAdmin;

Parameters

Name	Type	Description
`_migrator`	`address`	The new migrator address

setGasHelper

Sets the gas fees helper address

function setGasHelper(address _helper) external onlyAdmin;

Parameters

Name	Type	Description
`_helper`	`address`	The new helper address

withdrawGasFees

Withdraw gas received so far

function withdrawGasFees(address payable receiver) external;

Parameters

Name	Type	Description
`receiver`	`address payable`	the receiver address

updateZkVerifier

Updates IZkVerifier address

function updateZkVerifier(address _zkVerifier) external onlyAdmin;

Parameters

Name	Type	Description
`_zkVerifier`	`address`	the verifier address

updateAllowedCallerStatus

Set caller status for msg.sender

function updateAllowedCallerStatus(address caller, bool status) external override;

Parameters

Name	Type	Description
`caller`	`address`	The caller address
`status`	`bool`	The status to set for `caller`

liquidateExternal

Mints tokens after external verification

function liquidateExternal(
    bytes calldata journalData,
    bytes calldata seal,
    address[] calldata userToLiquidate,
    uint256[] calldata liquidateAmount,
    address[] calldata collateral,
    address receiver
) external override;

Parameters

Name	Type	Description
`journalData`	`bytes`	The journal data for minting (array of encoded journals)
`seal`	`bytes`	The Zk proof seal
`userToLiquidate`	`address[]`	Array of positions to liquidate
`liquidateAmount`	`uint256[]`	Array of amounts to liquidate
`collateral`	`address[]`	Array of collaterals to seize
`receiver`	`address`	The collateral receiver

mintExternal

Mints tokens after external verification

function mintExternal(
    bytes calldata journalData,
    bytes calldata seal,
    uint256[] calldata mintAmount,
    uint256[] calldata minAmountsOut,
    address receiver
) external override;

Parameters

Name	Type	Description
`journalData`	`bytes`	The journal data for minting (array of encoded journals)
`seal`	`bytes`	The Zk proof seal
`mintAmount`	`uint256[]`	Array of amounts to mint
`minAmountsOut`	`uint256[]`	Array of min amounts accepted
`receiver`	`address`	The tokens receiver

repayExternal

Repays tokens after external verification

function repayExternal(
    bytes calldata journalData,
    bytes calldata seal,
    uint256[] calldata repayAmount,
    address receiver
) external override;

Parameters

Name	Type	Description
`journalData`	`bytes`	The journal data for repayment (array of encoded journals)
`seal`	`bytes`	The Zk proof seal
`repayAmount`	`uint256[]`	Array of amounts to repay
`receiver`	`address`	The position to repay for

performExtensionCall

Initiates a withdraw operation

function performExtensionCall(uint256 actionType, uint256 amount, uint32 dstChainId) external payable override;

Parameters

Name	Type	Description
`actionType`	`uint256`	The actionType param (1 - withdraw, 2 - borrow)
`amount`	`uint256`	The amount to withdraw
`dstChainId`	`uint32`	The destination chain to recieve funds

mintOrBorrowMigration

Mints mTokens during migration without requiring underlying transfer

function mintOrBorrowMigration(bool isMint, uint256 amount, address receiver, address borrower, uint256 minAmount)
    external
    onlyMigrator;

Parameters

Name	Type	Description
`isMint`	`bool`
`amount`	`uint256`	The amount of underlying to be accounted for
`receiver`	`address`	The address that will receive the mTokens or the underlying in case of borrowing
`borrower`	`address`	The address that borrow is executed for
`minAmount`	`uint256`	The min amount of underlying to be accounted for

getProofData

Returns the proof data journal

function getProofData(address user, uint32 dstId) external view returns (uint256, uint256);

Parameters

Name	Type	Description
`user`	`address`	The user address for the proof
`dstId`	`uint32`	The destination chain identifier

Returns

Name	Type	Description
`<none>`	`uint256`	dataRoot The proof data root
`<none>`	`uint256`	journalHash The proof journal hash

_liquidateExternal

Processes a single liquidateExternal call from decoded journal

function _liquidateExternal(
    bytes memory singleJournal,
    address userToLiquidate,
    uint256 liquidateAmount,
    address collateral,
    address receiver
) internal;

Parameters

Name	Type	Description
`singleJournal`	`bytes`	Encoded journal entry
`userToLiquidate`	`address`	Account to be liquidated
`liquidateAmount`	`uint256`	Amount to liquidate
`collateral`	`address`	Collateral address to seize
`receiver`	`address`	Receiver of seized collateral

_mintExternal

Processes a single mintExternal call from decoded journal

function _mintExternal(bytes memory singleJournal, uint256 mintAmount, uint256 minAmountOut, address receiver)
    internal;

Parameters

Name	Type	Description
`singleJournal`	`bytes`	Encoded journal entry
`mintAmount`	`uint256`	Amount to mint
`minAmountOut`	`uint256`	Minimum amount out allowed
`receiver`	`address`	Receiver address

_repayExternal

Processes a single repayExternal call from decoded journal

function _repayExternal(bytes memory singleJournal, uint256 repayAmount, address receiver) internal;

Parameters

Name	Type	Description
`singleJournal`	`bytes`	Encoded journal entry
`repayAmount`	`uint256`	Amount to repay
`receiver`	`address`	Receiver address

_checkOutflow

Validates outflow limits via defender

function _checkOutflow(uint256 amount) internal;

Parameters

Name	Type	Description
`amount`	`uint256`	Amount to check

_onlyAdminOrRole

Ensures caller is admin or has specific role

function _onlyAdminOrRole(bytes32 _role) internal view;

Parameters

Name	Type	Description
`_role`	`bytes32`	Role identifier to check

_checkJournalData

Performs basic proof call checks

function _checkJournalData(uint32 dstChainId, uint32 chainId, address market, address sender) internal view;

Parameters

Name	Type	Description
`dstChainId`	`uint32`	Destination chain id
`chainId`	`uint32`	Source chain id
`market`	`address`	Market address encoded in proof
`sender`	`address`	Sender extracted from proof

_isAllowedFor

Checks if sender has specified role

function _isAllowedFor(address _sender, bytes32 role) internal view returns (bool);

Parameters

Name	Type	Description
`_sender`	`address`	Address to check
`role`	`bytes32`	Role identifier

Returns

Name	Type	Description
`<none>`	`bool`	True if allowed

_getChainsManagerRole

Retrieves chains manager role id

function _getChainsManagerRole() internal view returns (bytes32);

Returns

Name	Type	Description
`<none>`	`bytes32`	Role identifier

_getProofForwarderRole

Retrieves proof forwarder role id

function _getProofForwarderRole() internal view returns (bytes32);

Returns

Name	Type	Description
`<none>`	`bytes32`	Role identifier

_getBatchProofForwarderRole

Retrieves batch proof forwarder role id

function _getBatchProofForwarderRole() internal view returns (bytes32);

Returns

Name	Type	Description
`<none>`	`bytes32`	Role identifier

_getSequencerRole

Retrieves sequencer role id

function _getSequencerRole() internal view returns (bytes32);

Returns

Name	Type	Description
`<none>`	`bytes32`	Role identifier

_verifyProof

Verifies proof data and checks inclusion constraints

function _verifyProof(bytes calldata journalData, bytes calldata seal) internal view;

Parameters

Name	Type	Description
`journalData`	`bytes`	Encoded journal data
`seal`	`bytes`	Zk proof seal

_decodeJournals

Decodes encoded journals data

function _decodeJournals(bytes calldata data) internal pure returns (bytes[] memory);

Parameters

Name	Type	Description
`data`	`bytes`	Encoded journal data

Returns

Name	Type	Description
`<none>`	`bytes[]`	Decoded journals array

Structs

Accumulated

Struct for accumulated amounts per chain

struct Accumulated {
    mapping(address chain => uint256 amount) inPerChain;
    mapping(address chain => uint256 amount) outPerChain;
}

Malda