PolygonZkEVMBridgeV2.sol

Bridge contract deployed on Ethereum and all Polygon rollups. Responsible for managing the token interactions with other networks.

Functions¶

`constructor`¶

Disable initializers on the implementation following best practices.

  function constructor(
  ) public

`initialize`¶

The value of _polygonRollupManager on the L2 deployment of the contract is address(0), so an emergency state is not possible for the L2 deployment of the bridge.

  function initialize(
    uint32 _networkID,
    address _gasTokenAddress,
    uint32 _gasTokenNetwork,
    contract IBasePolygonZkEVMGlobalExitRoot _globalExitRootManager,
    address _polygonRollupManager,
    bytes _gasTokenMetadata
  ) external

Parameters¶

Name	Type	Description
`_networkID`	uint32	networkID
`_gasTokenAddress`	address	gas token address
`_gasTokenNetwork`	uint32	gas token network
`_globalExitRootManager`	contract IBasePolygonZkEVMGlobalExitRoot	global exit root manager address
`_polygonRollupManager`	address	polygonZkEVM address
`_gasTokenMetadata`	bytes	Abi encoded gas token metadata

`bridgeAsset`¶

Deposit add a new leaf to the Merkle tree.

  function bridgeAsset(
    uint32 destinationNetwork,
    address destinationAddress,
    uint256 amount,
    address token,
    bool forceUpdateGlobalExitRoot,
    bytes permitData
  ) public

Note

If this function is called with a reentrant token, it is possible to claimTokens in the same call, thus reducing the supply of tokens on this contract, and actually locking tokens in the contract.
Therefore we recommend to third-party bridges that if they do implement reentrant beforeTransfer for some reentrant tokens, not to call any external address.

Note

User/UI must be aware of the existing/available networks when choosing the destination network.

Parameters¶

Name	Type	Description
`destinationNetwork`	uint32	Network destination
`destinationAddress`	address	Address destination
`amount`	uint256	Amount of tokens
`token`	address	Token address, 0 address is reserved for ether
`forceUpdateGlobalExitRoot`	bool	Indicates if the new global exit root is updated or not
`permitData`	bytes	Raw data of the call `permit` of the token

`bridgeMessage`¶

Bridge message and send ETH value.

  function bridgeMessage(
    uint32 destinationNetwork,
    address destinationAddress,
    bool forceUpdateGlobalExitRoot,
    bytes metadata
  ) external

Note

User/UI must be aware of the existing/available networks when choosing the destination network.

Parameters¶

Name	Type	Description
`destinationNetwork`	uint32	Network destination
`destinationAddress`	address	Address destination
`forceUpdateGlobalExitRoot`	bool	Indicates if the new global exit root is updated or not
`metadata`	bytes	Message metadata

`bridgeMessageWETH`¶

Bridge message and send ETH value.

  function bridgeMessageWETH(
    uint32 destinationNetwork,
    address destinationAddress,
    uint256 amountWETH,
    bool forceUpdateGlobalExitRoot,
    bytes metadata
  ) external

Note

User/UI must be aware of the existing/available networks when choosing the destination network

Parameters¶

Name	Type	Description
`destinationNetwork`	uint32	Network destination
`destinationAddress`	address	Address destination
`amountWETH`	uint256	Amount of WETH tokens
`forceUpdateGlobalExitRoot`	bool	Indicates if the new global exit root is updated or not
`metadata`	bytes	Message metadata

`_bridgeMessage`¶

Bridge message and send ETH value.

  function _bridgeMessage(
    uint32 destinationNetwork,
    address destinationAddress,
    uint256 amountEther,
    bool forceUpdateGlobalExitRoot,
    bytes metadata
  ) internal

Parameters¶

Name	Type	Description
`destinationNetwork`	uint32	Network destination
`destinationAddress`	address	Address destination
`amountEther`	uint256	Amount of ether along with the message
`forceUpdateGlobalExitRoot`	bool	Indicates if the new global exit root is updated or not
`metadata`	bytes	Message metadata

`claimAsset`¶

Verify merkle proof and withdraw tokens/ETH.

  function claimAsset(
    bytes32[32] smtProofLocalExitRoot,
    bytes32[32] smtProofRollupExitRoot,
    uint256 globalIndex,
    bytes32 mainnetExitRoot,
    bytes32 rollupExitRoot,
    uint32 originNetwork,
    address originTokenAddress,
    uint32 destinationNetwork,
    address destinationAddress,
    uint256 amount,
    bytes metadata
  ) external

Parameters¶

`claimMessage`¶

Verify merkle proof and execute message. If the receiving address is an EOA, the call results as a success which means that the amount of ether transfers correctly, but the message does not trigger any execution.

  function claimMessage(
    bytes32[32] smtProofLocalExitRoot,
    bytes32[32] smtProofRollupExitRoot,
    uint256 globalIndex,
    bytes32 mainnetExitRoot,
    bytes32 rollupExitRoot,
    uint32 originNetwork,
    address originAddress,
    uint32 destinationNetwork,
    address destinationAddress,
    uint256 amount,
    bytes metadata
  ) external

Parameters¶

Name	Type	Description
`smtProofLocalExitRoot`	bytes32[32]	Smt proof to proof the leaf against the exit root
`smtProofRollupExitRoot`	bytes32[32]	Smt proof to proof the rollupLocalExitRoot against the rollups exit root
`globalIndex`	uint256	Global index is defined as:
191 bits	1 bit	32 bits
0	mainnetFlag	rollupIndex
note that only the rollup index will be used only in case the mainnet flag is 0
note that global index do not assert the unused bits to 0.
This means that when synching the events, the globalIndex must be decoded the same way that in the Smart contract
to avoid possible synch attacks
`mainnetExitRoot`	bytes32	Mainnet exit root
`rollupExitRoot`	bytes32	Rollup exit root
`originNetwork`	uint32	Origin network
`originAddress`	address	Origin address
`destinationNetwork`	uint32	Network destination
`destinationAddress`	address	Address destination
`amount`	uint256	message value
`metadata`	bytes	Abi encoded metadata if any, empty otherwise

`precalculatedWrapperAddress`¶

Returns the precalculated address of a wrapper using the token information.

  function precalculatedWrapperAddress(
    uint32 originNetwork,
    address originTokenAddress,
    string name,
    string symbol,
    uint8 decimals
  ) public returns (address)

Note

Updating the metadata of a token is not supported.
Since the metadata has relevance in the address deployed, this function does not return a valid wrapped address if the metadata provided is not the original one.

Parameters¶

Name	Type	Description
`originNetwork`	uint32	Origin network
`originTokenAddress`	address	Origin token address, 0 address is reserved for ether
`name`	string	Name of the token
`symbol`	string	Symbol of the token
`decimals`	uint8	Decimals of the token

`getTokenWrappedAddress`¶

Returns the address of a wrapper using the token information if already exist.

  function getTokenWrappedAddress(
    uint32 originNetwork,
    address originTokenAddress
  ) external returns (address)

Parameters¶

Name	Type	Description
`originNetwork`	uint32	Origin network
`originTokenAddress`	address	Origin token address, 0 address is reserved for ether

`activateEmergencyState`¶

Function to activate the emergency state. Can only be called by the Polygon ZK-EVM in extreme situations.

  function activateEmergencyState(
  ) external

`deactivateEmergencyState`¶

Function to deactivate the emergency state. Can only be called by the Polygon ZK-EVM.

  function deactivateEmergencyState(
  ) external

`_verifyLeaf`¶

Verify leaf and checks that it has not been claimed.

  function _verifyLeaf(
    bytes32[32] smtProofLocalExitRoot,
    bytes32[32] smtProofRollupExitRoot,
    uint256 globalIndex,
    bytes32 mainnetExitRoot,
    bytes32 rollupExitRoot,
    bytes32 leafValue
  ) internal

Parameters¶

Name	Type	Description
`smtProofLocalExitRoot`	bytes32[32]	Smt proof
`smtProofRollupExitRoot`	bytes32[32]	Smt proof
`globalIndex`	uint256	Index of the leaf
`mainnetExitRoot`	bytes32	Mainnet exit root
`rollupExitRoot`	bytes32	Rollup exit root
`leafValue`	bytes32	leaf value

`isClaimed`¶

Function to check if an index is claimed or not.

  function isClaimed(
    uint32 leafIndex,
    uint32 sourceBridgeNetwork
  ) external returns (bool)

Parameters¶

Name	Type	Description
`leafIndex`	uint32	Index
`sourceBridgeNetwork`	uint32	Origin network

`updateGlobalExitRoot`¶

Function to update the globalExitRoot if the last deposit is not submitted.

  function updateGlobalExitRoot(
  ) external

`_updateGlobalExitRoot`¶

Function to update the globalExitRoot.

  function _updateGlobalExitRoot(
  ) internal

`_permit`¶

Function to call token permit method of extended ERC20 + @param token ERC20 token address.

  function _permit(
    address amount,
    uint256 permitData
  ) internal

Parameters¶

Name	Type	Description
`amount`	address	Quantity that is expected to be allowed
`permitData`	uint256	Raw data of the call `permit` of the token

`_deployWrappedToken`¶

Internal function that uses create2 to deploy the wrapped tokens.

  function _deployWrappedToken(
    bytes32 salt,
    bytes constructorArgs
  ) internal returns (contract TokenWrapped newWrappedToken)

Parameters¶

Name	Type	Description
`salt`	bytes32	Salt used in create2 params,
tokenInfoHash will be used as salt for all wrappeds except for bridge native WETH, that will be bytes32(0)
`constructorArgs`	bytes	Encoded constructor args for the wrapped token

`_safeSymbol`¶

Provides a safe ERC20.symbol version which returns NO_SYMBOL as fallback string.

  function _safeSymbol(
    address token
  ) internal returns (string)

Parameters¶

Name	Type	Description
`token`	address	The address of the ERC-20 token contract

`_safeName`¶

Provides a safe ERC20.name version which returns NO_NAME as fallback string.

  function _safeName(
    address token
  ) internal returns (string)

Parameters¶

Name	Type	Description
`token`	address	The address of the ERC-20 token contract.

`_safeDecimals`¶

Provides a safe ERC20.decimals version which returns 18 as fallback value.

  function _safeDecimals(
    address token
  ) internal returns (uint8)

Warn

Tokens with (decimals > 255) are not supported.

Parameters¶

Name	Type	Description
`token`	address	The address of the ERC-20 token contract

`_returnDataToString`¶

Function to convert returned data to string; returns NOT_VALID_ENCODING as fallback value.

  function _returnDataToString(
    bytes data
  ) internal returns (string)

Parameters¶

Name	Type	Description
`data`	bytes	returned data

`getTokenMetadata`¶

Returns the encoded token metadata.

  function getTokenMetadata(
    address token
  ) public returns (bytes)

Parameters¶

Name	Type	Description
`token`	address	Address of the token

`calculateTokenWrapperAddress`¶

Returns the precalculated address of a wrapper using the token address.

  function calculateTokenWrapperAddress(
    uint32 originNetwork,
    address originTokenAddress,
    address token
  ) external returns (address)

Note

Updating the metadata of a token is not supported.
Since the metadata has relevance in the address deployed, this function does not return a valid wrapped address if the metadata provided is not the original one.

Parameters¶

Name	Type	Description
`originNetwork`	uint32	Origin network
`originTokenAddress`	address	Origin token address, 0 address is reserved for ether
`token`	address	Address of the token to calculate the wrapper address

Events¶

`BridgeEvent`¶

Emitted when bridge assets or messages to another network.

  event BridgeEvent(
  )

`ClaimEvent`¶

Emitted when a claim is done from another network.

  event ClaimEvent(
  )

`NewWrappedToken`¶

Emitted when a new wrapped token is created.

  event NewWrappedToken(
  )

PolygonZkEVMBridgeV2.sol

Functions¶

constructor¶

initialize¶

Parameters¶

bridgeAsset¶

Parameters¶

bridgeMessage¶

Parameters¶

bridgeMessageWETH¶

Parameters¶

_bridgeMessage¶

Parameters¶

claimAsset¶

Parameters¶

claimMessage¶

Parameters¶

precalculatedWrapperAddress¶

Parameters¶

getTokenWrappedAddress¶

Parameters¶

activateEmergencyState¶

deactivateEmergencyState¶

_verifyLeaf¶

Parameters¶

isClaimed¶

Parameters¶

updateGlobalExitRoot¶

_updateGlobalExitRoot¶

_permit¶

Parameters¶

_deployWrappedToken¶

Parameters¶

_safeSymbol¶

Parameters¶

_safeName¶

Parameters¶

_safeDecimals¶

Parameters¶

_returnDataToString¶

Parameters¶

getTokenMetadata¶

Parameters¶

calculateTokenWrapperAddress¶

Parameters¶

Events¶

BridgeEvent¶

ClaimEvent¶

NewWrappedToken¶

`constructor`¶

`initialize`¶

`bridgeAsset`¶

`bridgeMessage`¶

`bridgeMessageWETH`¶

`_bridgeMessage`¶

`claimAsset`¶

`claimMessage`¶

`precalculatedWrapperAddress`¶

`getTokenWrappedAddress`¶

`activateEmergencyState`¶

`deactivateEmergencyState`¶

`_verifyLeaf`¶

`isClaimed`¶

`updateGlobalExitRoot`¶

`_updateGlobalExitRoot`¶

`_permit`¶

`_deployWrappedToken`¶

`_safeSymbol`¶

`_safeName`¶

`_safeDecimals`¶

`_returnDataToString`¶

`getTokenMetadata`¶

`calculateTokenWrapperAddress`¶

`BridgeEvent`¶

`ClaimEvent`¶

`NewWrappedToken`¶