Factory

Overview

The Factory contract is a generalized deployment mechanism for creating upgradeable proxy instances of pre-approved implementations. It tracks multiple implementation versions, proposal workflows, blacklisting for security, and ownership-based access control.

It conforms to the IFactory interface and supports deploying any IFactoryEntity-compliant contracts via TransparentUpgradeableProxy, using initialize() for configuration.

Key Capabilities

• Versioned Deployment: Track multiple logic contract versions, each deployable by index.

• Proposal System: Allow anyone to propose implementations, with owner approval required.

• Blacklist Mechanism: Prevent deployment of insecure or deprecated versions.

• Deterministic Deployments: Uses create2 salt to ensure predictable addresses.

• Entity Tracking: Keeps a registry of all deployed entities.

Storage Structure

The contract uses a deterministic storage layout via:

bytes32 _factoryStorageSlot = SlotLibrary.getSlot("Factory", name_, version_);

Storage fields (in FactoryStorage) include:

Field	Description
entities	Set of all deployed proxy instances
implementations	Approved logic contract addresses
proposals	Pending implementation proposals
isBlacklisted	Mapping from version → is blacklisted

Initialization

function initialize(bytes calldata data) external initializer

• Accepts encoded owner address

• Sets initial admin and emits Initialized

Entity Deployment

function create(uint256 version, address owner, bytes calldata initParams) external returns (address instance)

Deploys a new TransparentUpgradeableProxy:

• Uses implementation from implementations.at(version)

• Rejects if version is out-of-bounds or blacklisted

• Uses salt = keccak256(version, owner, initParams, currentEntityCount) for deterministic deployment

• Calls initialize(initParams) on the new proxy

Emits:

event Created(address instance, uint256 version, address owner, bytes initParams);

Implementation Management

Propose New Implementation

function proposeImplementation(address implementation) external

• Fails if already in implementations or proposals

• Adds to proposals

• Emits: ProposeImplementation(implementation)

• Permissionless function

Accept Proposed Implementation

function acceptProposedImplementation(address implementation) external onlyOwner

• Only callable by owner

• Fails if not proposed

• Moves from proposals → implementations

• Emits: AcceptProposedImplementation(implementation)

Blacklisting

function setBlacklistStatus(uint256 version, bool flag) external onlyOwner

• Blocks deployments using specific version

• Enforces that version index exists

• Emits: SetBlacklistStatus(version, flag)

View Functions

Function	Returns
entities()	Total number of deployed entities
entityAt(index)	Deployed entity at index
isEntity(address)	Checks if address is a deployed entity
implementations()	Total implementation count
implementationAt(index)	Implementation at index
proposals()	Total proposals pending approval
proposalAt(index)	Proposal at index
isBlacklisted(version)	Whether a version is blocked from deployment

Access Control

• Uses OwnableUpgradeable

• Only owner can accept implementations and blacklist versions

Security Considerations

• Immutable logic whitelist: Only approved contracts can be deployed

• Blacklisting: Emergency response for vulnerabilities

• Replay protection: Deployment salt ensures unique addresses

• Decentralized proposals: Anyone can propose implementations, but only owner can accept