CCIP v2.0.0 Proxy API Reference

Summary

Proxy is a minimal call-forwarding contract that:

• Forwards all fallback calls to a configurable target using call.
• Allows the owner to update the target address.
• Allows withdrawal of accumulated fee tokens to a configurable fee aggregator.

It does not use delegatecall. Forwarded calls execute in the context of the target contract.

Contract

chains/evm/contracts/Proxy.sol

Import

import {Proxy} from "chainlink-ccip/chains/evm/contracts/Proxy.sol";

Target + upgrade model

• The target address is stored in s_target.
• All unknown calls are forwarded via call.
• The owner may update the target via setTarget.
• No storage layout coupling exists (no delegatecall).
• Ether is not forwarded (value = 0).

This is a forwarding proxy, not an upgradeable storage proxy.

Inheritance

• Ownable2StepMsgSender
• ITypeAndVersion

typeAndVersion

string public constant override typeAndVersion =
  "Proxy 2.0.0-dev";

State

Constants

None declared beyond typeAndVersion.

Immutables

None declared.

Storage

address internal s_target;
address internal s_feeAggregator;

• s_target — forwarding destination.
• s_feeAggregator — recipient of withdrawn fee token balances.

External API (forwarded surface)

getTarget

function getTarget()
  external
  view
  virtual
  returns (address);

Returns s_target.

setTarget

function setTarget(address target)
  external
  virtual
  onlyOwner;

Reverts:

error ZeroAddressNotAllowed();

If target == address(0).

Internally calls _setTarget.

getFeeAggregator

function getFeeAggregator()
  external
  view
  virtual
  returns (address);

Returns s_feeAggregator.

setFeeAggregator

function setFeeAggregator(address feeAggregator)
  external
  virtual
  onlyOwner;

Internally calls _setFeeAggregator.

Zero address is permitted but may cause downstream withdrawal reverts.

withdrawFeeTokens

function withdrawFeeTokens(
  address[] calldata feeTokens
) external virtual;

Calls:

FeeTokenHandler._withdrawFeeTokens(
  feeTokens,
  s_feeAggregator
);

Permissionless.

fallback

fallback() external virtual;

Behavior:

1. Copies calldata.
2. Executes:

call(gas(), s_target, 0, calldataPtr, calldataSize, 0, 0)

3. Returns or reverts with the returned data.

Notes:

• Uses call, not delegatecall.
• Does not forward Ether.
• Proxy storage is never modified by fallback.

Internal Functions

_setTarget

function _setTarget(address target) internal;

Emits:

event TargetUpdated(
  address indexed oldTarget,
  address indexed newTarget
);

_setFeeAggregator

function _setFeeAggregator(address feeAggregator) internal;

Emits:

event FeeAggregatorUpdated(
  address indexed oldFeeAggregator,
  address indexed newFeeAggregator
);

Events

event TargetUpdated(
  address indexed oldTarget,
  address indexed newTarget
);

event FeeAggregatorUpdated(
  address indexed oldFeeAggregator,
  address indexed newFeeAggregator
);

Errors

error ZeroAddressNotAllowed();

Security model

• Only owner may update target or fee aggregator.
• No delegatecall prevents storage collision.
• Calls to non-contract targets revert.
• Withdrawal is permissionless but funds always go to s_feeAggregator.
• Misconfiguration of s_target can halt functionality.

Related Interfaces & Contracts

• FeeTokenHandler
• ITypeAndVersion
• Ownable2StepMsgSender