Common Utilities - ZKsync Docs

Provides essential utilities for building on ZKsync Era. These utilities include constants, useful addresses, and functions that facilitate the development and interaction with the ZKsync blockchain.

Constants

L1 to L2 alias offset

Used for applying and undoing aliases on contract addresses during bridging from L1 to L2.

L1ToL2AliasOffset := common.HexToAddress("0x1111000000000000000000000000000000001111")

Useful addresses

ETH token on L1

EthAddress := common.HexToAddress("0x0000000000000000000000000000000000000000")

Legacy ETH token on L1

LegacyEthAddress := common.HexToAddress("0x0000000000000000000000000000000000000000")

ETH token address in contracts

EthAddressInContracts := common.HexToAddress("0x0000000000000000000000000000000000000001")

Base token alias on ZKsync Era

L2BaseTokenAddress := common.HexToAddress("0x000000000000000000000000000000000000800a")

Bootloader

BootloaderFormalAddress := common.HexToAddress("0x0000000000000000000000000000000000008001")

Contract deployer

ContractDeployerAddress := common.HexToAddress("0x0000000000000000000000000000000000008006")

L1 messenger

L1MessengerAddress := common.HexToAddress("0x0000000000000000000000000000000000008008")

Nonce holder

NonceHolderAddress := common.HexToAddress("0x0000000000000000000000000000000000008003")

Gas

`DefaultGasPerPubdataLimit`

Use a large amount of gas per pubdata for signing on layer 2.
The amount ensures any reasonable limit is accepted.

The operator is NOT required to use the actual value and can use any value up to that signed by the user.

DefaultGasPerPubdataLimit := big.NewInt(50_000)

`RequiredL1ToL2GasPerPubdataLimit`

The current required gas per pubdata for L1->L2 transactions.

RequiredL1ToL2GasPerPubdataLimit := big.NewInt(800)

Functions

`ApplyL1ToL2Alias`

Converts the address that submitted a transaction to the inbox on L1 to the msg.sender viewed on L2.

Inputs

Parameter	Type	Description
`address`	`common.Address`	Contract address.

Outputs

Returns the msg.sender of the L1->L2 transaction as the common.Address of the contract that initiated the transaction.

More info

During a normal transaction, if contract A calls contract B, the msg.sender is A.
During L1->L2 communication, if an EOA X calls contract B, the msg.sender is X.
During L1->L2 communication, if a contract A calls contract B, the msg.sender is ApplyL1ToL2Alias(A).

func ApplyL1ToL2Alias(address common.Address) common.Address

`Create2Address`

Generates a future-proof contract address using salt plus bytecode which allows determination of an address before deployment.

The ZKsync Era implementation is slightly different from Ethereum.

Inputs

Parameter	Type	Description
`sender`	`common.Address`	Sender address.
`bytecode`	`[]byte`	Output from zkSolc.
`constructor`	`[]byte`	ABI encoded constructor arguments.
`salt`	`[]byte`	Randomization element.

Outputs

Returns a common.Address of the future contract.

func Create2Address(sender common.Address, bytecode, constructor, salt []byte) (common.Address, error)

The prefix is equal to keccak256("zksyncCreate2").

`CreateAddress`

Generates a contract address from deployer's account and nonce.

Inputs

Parameter	Type	Description
`sender`	`common.Address`	Sender address.
`nonce`	`*big.Int` object	Sender nonce.

Outputs

Returns a common.Address of the future contract.

func CreateAddress(sender common.Address, nonce *big.Int) (common.Address, error)

The prefix is equal to keccak256("zksyncCreate").

`CreateETH`

Creates ETH token with appropriate Name, Symbol and Decimals values.

func CreateETH() *types.Token

`EncodeCreate`

Returns the encoded constructor data for CREATE method used for smart contract deployment.

Inputs

Parameter	Type	Description
`bytecode`	`[]byte`	Output from zkSolc.
`calldata`	`[]byte`	ABI encoded constructor arguments.

func EncodeCreate(bytecode, calldata []byte) ([]byte, error)

`EncodeCreate2`

Returns the encoded constructor data for CREATE2 method used for smart contract deployment.

Inputs

Parameter	Type	Description
`bytecode`	`[]byte`	Output from zkSolc.
`calldata`	`[]byte`	ABI encoded constructor arguments.
`salt`	`[]byte`	Randomization element.

func EncodeCreate2(bytecode, calldata, salt []byte) ([]byte, error)

`EncodeCreateAccount`

Returns the encoded constructor data for CREATE method used for smart account deployment.

Inputs

Parameter	Type	Description
`bytecode`	`[]byte`	Output from zkSolc.
`calldata`	`[]byte`	ABI encoded constructor arguments.
`version`	`types.AccountAbstractionVersion`	Account abstraction version.

 EncodeCreate2Account(bytecode, calldata, version types.AccountAbstractionVersion) ([]byte, error)

`EncodeCreate2Account`

Returns the encoded constructor data for CREATE2 method used for smart account deployment.

Inputs

Parameter	Type	Description
`bytecode`	`[]byte`	Output from zkSolc.
`calldata`	`[]byte`	ABI encoded constructor arguments.
`salt`	`[]byte`	Randomization element.
`version`	`types.AccountAbstractionVersion`	Account abstraction version.

 EncodeCreate2Account(bytecode, calldata, salt []byte, version types.AccountAbstractionVersion) ([]byte, error)

`Erc20BridgeCalldata`

Returns the calldata sent by an L1 ERC20 bridge to its L2 counterpart during token-bridging.

Inputs

Parameter	Type	Description
`l1TokenAddress`	`common.Address`	Token address on L1.
`l1Sender`	`common.Address`	Sender address on L1.
`l2Receiver`	`common.Address`	Recipient address on L2.
`amount`	`*big.Int`	Gas fee for the number of tokens to bridge.
`bridgeData`	`*big.Int`	Data

func Erc20BridgeCalldata(l1TokenAddress, l1Sender, l2Receiver common.Address, amount *big.Int, bridgeData []byte)

`Erc20DefaultBridgeData`

Returns the data needed for correct initialization of an L1 token counterpart on L2.

Inputs

Parameter	Type	Description
`l1TokenAddress`	`common.Address`	Token address on L1.
`backend`	`bind.ContractBackend`	Client that is able to work with contracts on a read-write basis.

Outputs

An ABI-encoded []byte which contains token name, symbol and decimals.

func Erc20DefaultBridgeData(l1TokenAddress common.Address, backend bind.ContractBackend) ([]byte, error)

`HashBytecode`

Returns the hash of given bytecode.

Inputs

Parameter	Type	Description
`bytecode`	`[]byte`	Bytecode.

func HashBytecode(bytecode []byte) ([]byte, error)

`ReadStandardJson`

Reads standard-json file generated as output from zksolc. Returns standard json configuration and extracted contracts abi and bytecode from config file.

Inputs

Parameter	Type	Description
`path`	`string`	Path to the standard-json file.

func ReadStandardJson(path string) (*types.StandardConfiguration, abi.ABI, []byte, error)

`UndoL1ToL2Alias`

Converts and returns the msg.sender viewed on L2 to the address that submitted a transaction to the inbox on L1.

Inputs

Parameter	Type	Description
`address`	`common.Address`	Sender address.

Outputs

Returns the msg.sender of the L2->L1 transaction as the common.Address of the contract that initiated the transaction.

func UndoL1ToL2Alias(address common.Address) common.Address