---
title: Core Contract (EVM)
description: Reference for the Wormhole Core contract on EVM chains. Covers the proxy structure, components, state variables, functions, events, and errors.
categories:
- Reference
url: https://wormhole.com/docs/products/messaging/reference/core-contract-evm/
word_count: 1963
token_estimate: 4016
---

# Core Contract (EVM)

The [Wormhole Core Contract on EVM](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank} chains is a proxy-based contract responsible for receiving and verifying Wormhole messages (VAAs). It implements the messaging interface and delegates logic to upgradeable implementation contracts.

## Structure Overview

The Wormhole Core system consists of a proxy contract and a modular implementation constructed through layered inheritance.

```text
Wormhole.sol (Proxy)
└── Implementation.sol
    └── Governance.sol
        ├── Getters.sol
        ├── GovernanceStructs.sol
        ├── Messages.sol
        ├── Setters.sol
        └── Structs.sol
```

**Key Components:**

 - **Wormhole.sol**: The upgradeable proxy contract that delegates all logic to `Implementation.sol`.
 - **Implementation.sol**: The main logic contract, which handles message publication and initialization. Inherits from Governance.sol.
 - **Governance.sol**: Core governance logic for processing upgrades, setting fees, and updating the Guardian set. Also responsible for verifying governance VAAs and performing privileged actions.
 - **Getters.sol**: Exposes view functions to access internal contract state, such as current Guardian sets, fees, and contract configuration.
 - **GovernanceStructs.sol**: Provides structures and helpers for processing governance-related VAAs.
 - **Messages.sol**: Handles VAA parsing and verification.
 - **Setters.sol**: Contains internal functions for mutating contract state.
 - **Structs.sol**: Defines core data structures like GuardianSet and VM (VAA Message) used across multiple modules.

## State Variables

 - **`provider` ++"Structs.Provider"++**: Holds metadata like `chainId`, `governanceChainId`, and `governanceContract`. This is a nested struct.
 - **`guardianSets` ++"mapping(uint32 => GuardianSet)"++**: Mapping of all Guardian sets by index.
 - **`guardianSetIndex` ++"uint32"++**: Index of the currently active Guardian set.
 - **`guardianSetExpiry` ++"uint32"++**: How long a Guardian set remains valid after it's replaced (in seconds).
 - **`sequences` ++"mapping(address => uint64)"++**: Tracks message sequences per emitter (used to enforce message ordering).
 - **`consumedGovernanceActions` ++"mapping(bytes32 => bool)"++**: Used to prevent governance VAAs from being reused (replay protection).
 - **`initializedImplementations` ++"mapping(address => bool)"++**: Tracks which implementation addresses have been initialized (for upgrade safety).
 - **`messageFee` ++"uint256"++**: The amount (in native gas token) required to post a message. Set via governance.
 - **`evmChainId` ++"uint256"++**: The actual EVM chain ID (e.g., 1 for Ethereum, 10 for Optimism). Used in fork recovery.

## Events

### LogMessagePublished

Emitted when a message is published via `publishMessage`. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*

```solidity
event LogMessagePublished(
    address indexed sender,
    uint64 sequence,
    uint32 nonce,
    bytes payload,
    uint8 consistencyLevel
)
```

??? interface "Parameters"

    `sender` ++"address"++  

    Address that called `publishMessage`.

    ---

    `sequence` ++"uint64"++

    The sequence number of the message.

    ---

    `nonce` ++"uint32"++

    The provided nonce.

    ---

    `payload` ++"bytes"++

    The payload that was published.

    ---

    `consistencyLevel` ++"uint8"++

    Finality level requested.

### ContractUpgraded

Emitted when the Core Contract is upgraded to a new implementation via governance. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

```solidity
event ContractUpgraded(
    address indexed oldContract,
    address indexed newContract
)
```

??? interface "Parameters"

    `oldContract` ++"address"++

    The address of the previous implementation.

    ---

    `newContract` ++"address"++

    The address of the new implementation.

### GuardianSetAdded

Emitted when a new Guardian set is registered via governance. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

```solidity
event GuardianSetAdded(
    uint32 indexed index
)
```

??? interface "Parameters"

    `index` ++"uint32"++

    Index of the newly added Guardian set.

### LogGuardianSetChanged

Emitted when the active Guardian set is changed. *(Defined in [State.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/State.sol){target=\_blank})*

```solidity
event LogGuardianSetChanged(
    uint32 oldGuardianIndex,
    uint32 newGuardianIndex
)
```

??? interface "Parameters"

    `oldGuardianIndex` ++"uint32"++

    The previous active Guardian set index.

    ---

    `newGuardianIndex` ++"uint32"++

    The new active Guardian set index.

## Functions

### publishMessage

Publishes a message to Wormhole's Guardian Network. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*

```solidity
function publishMessage(
    uint32 nonce,
    bytes memory payload,
    uint8 consistencyLevel
) public payable returns (uint64 sequence)
```

??? interface "Parameters"

    `nonce` ++"uint32"++

    Custom sequence identifier for the emitter.

    ---

    `payload` ++"bytes"++

    Arbitrary user data to be included in the message.

    ---

    `consistencyLevel` ++"uint8"++

    Finality requirement for Guardian attestation (e.g., safe or finalized).

??? interface "Returns"

    `sequence` ++"uint64"++

    Unique sequence number assigned to this message.

### getCurrentGuardianSetIndex

Returns the index of the currently active Guardian set. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*

Each VAA includes the index of the Guardian set that signed it. This function allows contracts to retrieve the current index, ensuring the VAA is verified against the correct set.

```solidity
function getCurrentGuardianSetIndex() external view returns (uint32)
```

??? interface "Returns"

    `index` ++"uint32"++

    The index of the active Guardian set used to verify signatures.

### getGuardianSet

Retrieves metadata for a given Guardian set index. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*

```solidity
function getGuardianSet(uint32 index) external view returns (address[] memory keys, uint32 expirationTime)
```

??? interface "Parameters"

    `index` ++"uint32"++

    Guardian set index to query.

??? interface "Returns"

    `keys` ++"address[]"++

    Public keys of the guardians in this set.

    ---

    `expirationTime` ++"uint32"++

    Timestamp after which the Guardian set is considered expired.

### getGuardianSetExpiry

Returns the expiration time of a specific Guardian set index. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*

```solidity
function getGuardianSetExpiry(uint32 index) external view returns (uint32)
```

??? interface "Parameters"

    `index` ++"uint32"++

    The index of the Guardian set to query.

??? interface "Returns"

    `expiry` ++"uint32"++

    UNIX timestamp after which the set is no longer valid.

### messageFee

Returns the current fee (in native tokens) required to publish a message. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*

```solidity
function messageFee() public view returns (uint256)
```

??? interface "Returns"

    `fee` ++"uint256"++

    Fee in Wei required to publish a message successfully. Must be sent as `msg.value`.

### nextSequence

Retrieves the next sequence number for a given emitter address. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*

```solidity
function nextSequence(address emitter) external view returns (uint64)
```

??? interface "Parameters"

    `emitter` ++"address"++

    The address for which the next sequence will be issued.

??? interface "Returns"

    `sequence` ++"uint64"++

    The next sequence number for the specified emitter.

### parseAndVerifyVM

Verifies signatures and parses a signed VAA. *(Defined in [Messages.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Messages.sol){target=\_blank})*

```solidity
function parseAndVerifyVM(bytes memory encodedVM)
    external
    view
    returns (
        VM memory vm,
        bool valid,
        string memory reason
    )
```

??? interface "Parameters"

    `encodedVM` ++"bytes"++

    Serialized signed VAA from Guardians.

??? interface "Returns"

    `vm` ++"VM memory"++

    Full parsed VAA contents

    ---

    `valid` ++"bool"++

    Whether the VAA is valid according to the current Guardian set.

    ---

    `reason` ++"string"++

    Reason for invalidity if `valid` is false (invalid).

### verifyVM

Performs low-level VAA signature verification. *(Defined in [Messages.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Messages.sol){target=\_blank})*

```solidity
function verifyVM(bytes memory encodedVM)
    public view returns (bool isValid, string memory reason)
```

??? interface "Parameters"

    `encodedVM` ++"bytes"++

    Serialized signed VAA to verify.

??? interface "Returns"

    `isValid` ++"bool"++

    `true` if the signatures are valid and meet the quorum.

    ---

    `reason` ++"string"++

    Explanation for failure if `isValid` is `false`.

### verifySignatures

Used to verify individual Guardian signatures against a VAA digest. *(Defined in [Messages.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Messages.sol){target=\_blank})*

```solidity
function verifySignatures(
    bytes32 hash,
    Structs.Signature[] memory signatures,
    GuardianSet memory guardianSet
) public view returns (bool)
```

??? interface "Parameters"

    `hash` ++"bytes32"++

    The message digest to verify.

    ---

    `signatures` ++"Structs.Signature[]"++

    An array of Guardian signatures.

    ---

    `guardianSet` ++"GuardianSet memory"++

    Guardian set to validate against.

??? interface "Returns"

    `isValid` ++"bool"++

    `true` if the required number of valid signatures is present.

### quorum

Returns the number of Guardian signatures required to reach quorum. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

```solidity
function quorum() public view returns (uint8)
```

??? interface "Returns"

    `quorum` ++"uint8"++

    Number of valid Guardian signatures required to reach consensus for VAA verification.

### chainId

Returns Wormhole chain ID used internally by the protocol. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*

```solidity
function chainId() public view returns (uint16)
```

??? interface "Returns"

    `id` ++"uint16"++

    Wormhole-specific chain identifier. 

### evmChainId

Returns the EVM chain ID (i.e., value from `block.chainid`). *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*

```solidity
function evmChainId() public view returns (uint256)
```

??? interface "Returns"

    `id` ++"uint256"++

    Native EVM chain ID for the current network.

## Errors

### Invalid Fee

Reverts when the message fee (`msg.value`) sent is not equal to the required fee returned by `messageFee()`. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*

### Unsupported

Reverts on any call to the fallback function. The contract does not support arbitrary calls. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*

### The Wormhole Contract Does Not Accept Assets

Reverts when native tokens (ETH) are sent directly to the contract via the `receive()` function. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*

### Already Initialized

Reverts when trying to call `initialize()` on an implementation that has already been initialized. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank}, via `initializer` modifier)*

### Unknown Chain ID

Reverts inside the `initialize()` function if the chain ID stored by the contract does not match any known Wormhole chain. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*

### Invalid Fork

Reverts when attempting to perform a governance action intended only for forked chains on a non-forked chain. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Invalid Module

Reverts if the VAA’s module field doesn’t match the expected "Core" module. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Invalid Chain

Reverts if the VAA’s target chain doesn’t match the chain on which this contract is deployed. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### New Guardian Set is Empty

Reverts when trying to register a new Guardian set that has no keys. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Index Must Increase in Steps of 1

Reverts when the new Guardian set index is not exactly one greater than the current. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Not a Fork

Reverts when trying to recover chain ID on a non-forked chain. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Invalid EVM Chain

Reverts if the recovered chain ID doesn't match the current `block.chainid`. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Governance Action Already Consumed

Reverts when the same governance VAA is submitted more than once. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Wrong Governance Contract

Reverts when the governance VAA’s emitter address doesn't match the expected governance contract address. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Wrong Governance Chain

Reverts when the governance VAA’s emitter chain doesn't match the expected governance chain (Solana). *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*

### Not Signed by Current Guardian Set

Reverts if the Guardian set index in the VAA doesn’t match the current Guardian set. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*