Access Control Visualizer
Visualize and analyze smart contract access control patterns and role hierarchies
1. What is Access Control?
Access control restricts who can call certain functions in a smart contract. Common patterns include Ownable (single owner), AccessControl (role-based), and custom role systems.
2. How does it work?
Access control uses modifiers and mapping structures to check caller permissions before executing functions. Roles are represented as bytes32 identifiers, and each address can have multiple roles. Admin roles can grant or revoke roles, creating hierarchical permission systems.
OpenZeppelin AccessControl
OpenZeppelin's AccessControl provides a role-based access control mechanism with role hierarchies. Each role has an admin role that can grant/revoke that role to addresses.
Role Hierarchy
DEFAULT_ADMIN_ROLE is typically the top-level admin that can manage all other roles. Other common roles include MINTER_ROLE, PAUSER_ROLE, BURNER_ROLE, and UPGRADER_ROLE.
Security Best Practices
Always use access control for privileged functions, prefer role-based over single owner for flexibility, use two-step ownership transfer, and carefully consider renounceOwnership implications.