BASENAMES

This repository contains code for minting and managing ENS subdomains on the Base network as base.eth subdomains.

It supports:

• Registering base.eth subdomains on Base natively
• Managing the name with a public resolver, allowing an owner or operator to set address records, text records, dns records, etc.
• ERC721 subdomain tokens (Opensea)

OVERVIEW

Basenames are a core onchain building block that enables anyone to establish their identity on Base by registering human-readable names for their address(es). They are a fully onchain solution which leverages ENS infrastructure deployed on Base.

CONTRACT ADDRESSES

Ethereum Mainnet

| Contract | Address | | -------- | ------- | | L1Resolver | 0xde9049636F4a1dfE0a64d1bFe3155C0A14C54F31 |

Base Mainnet

| Contract | Address | | -------- | ------- | | Registry | 0xb94704422c2a1e396835a571837aa5ae53285a95 | | BaseRegistrar | 0x03c4738ee98ae44591e1a4a4f3cab6641d95dd9a | | RegistrarController | 0x4cCb0BB02FCABA27e82a56646E81d8c5bC4119a5 | | Launch Price Oracle | 0xd53b558e1f07289acedf028d226974abba258312 | | Price Oracle | 0x508CFE43aa84b8048cB6d39037cE0dc96d8aDc75 | | ReverseRegistrar | 0x79ea96012eea67a83431f1701b3dff7e37f9e282 | | L2Resolver | 0xC6d566A56A1aFf6508b41f6c90ff131615583BCD | | MigrationController | 0x8d5ef54f900c82da119B4a7F960A92F3Fa8daB43 | | UpgradeableRegistrarController (Implementation) | 0x9ad14968093C5E8C2A8CC86f6868CFEE8C659717 | | UpgradeableRegistrarController (Proxy) | 0xa7d2607c6BD39Ae9521e514026CBB078405Ab322 | | UpgradeableL2Resolver (Implementation) | 0xf74b949f2105178eEEd4Ef35a131715E967337ab | | UpgradeableL2Resolver (Proxy) | 0x426fA03fB86E510d0Dd9F70335Cf102a98b10875 | | ProxyAdmin | 0x6c8E23DaCCc002d2Bca7608EC0351E434E74d5a8 |

Sepolia

| Contract | Address | | -------- | ------- | | L1Resolver | 0x084D10C07EfEecD9fFc73DEb38ecb72f9eEb65aB |

Base Sepolia

| Contract | Address | | -------- | ------- | | Registry | 0x1493b2567056c2181630115660963E13A8E32735 | | BaseRegistrar | 0xa0c70ec36c010b55e3c434d6c6ebeec50c705794 | | RegistrarController | 0x49ae3cc2e3aa768b1e5654f5d3c6002144a59581 | | Launch Price Oracle | 0x2afF926546f5fbe3E10315CC9C0827AF1A167aC8 | | Price Oracle | 0x2b73408052825e17e0fe464f92de85e8c7723231 | | ReverseRegistrar | 0x876eF94ce0773052a2f81921E70FF25a5e76841f | | L2Resolver | 0x6533C94869D28fAA8dF77cc63f9e2b2D6Cf77eBA | | MigrationController | 0xE8A87034a06425476F2bD6fD14EA038332Cc5e10 | | UpgradeableRegistrarController (Implementation) | 0xb53e99F4a96dce67E772038a32aBd1131E216770 | | UpgradeableRegistrarController (Proxy) | 0x82c858CDF64b3D893Fe54962680edFDDC37e94C8 | | UpgradeableL2Resolver (Implementation) | 0xC014B9c02b0EDeA17255Ce019e6ab6c24E4AD073 | | UpgradeableL2Resolver (Proxy) | 0x85C87e548091f204C2d0350b39ce1874f02197c6 | | ProxyAdmin | 0xE6F8309b75E73ace9d2b73531880126D883ae904 |

Functional Diagram

The system architecture can be functionally organized into three categories:

1. An L1 resolver enabling cross-chain resolution for the base.eth 2LD.
2. An ENS-like registry/registrar/resolver system deployed on Base enabling *.base.eth subdomains to be registered and managed.
3. An off-chain gateway for serving CCIP requests required to comply with ENSIP-10.

ARCHITECTURE

The core functionality of Base Usernames should look familiar to anyone that's looked under the hood at the ENS contracts. We implement a slimmed down fork of the ENS contracts here.

| Contract | Role | ENS Implementation | Base Usernames Implementation | | -------- | ----- | ------------------ | ----------------------------- | |Registry | Stores Records of subdomains in a flat structure | ENSRegistry.sol | Registry.sol | | BaseRegistrar | Tokenizes names, manages ownership and stores expiry | BaseRegistrarImplementation.sol | BaseRegistrar.sol | | ReverseRegistrar | Manages the reverse lookup to allow the setting of "primary" names for an address | ReverseRegistrar.sol | ReverseRegistrar.sol | | L1 Resolver | Enables cross-chain, wildcard resolution from L1 | OffchainResolver.sol | L1Resolver.sol | | L2 Resolver | A standard public resolver for storing records associated with namespaces | PublicResolver.sol | L2Resolver.sol | | Registrar Controller | A permissioned contract which manages registration payment | ETHRegistrarController.sol | RegistrarController.sol | | Stable Price Oracle | The source of pricing based on name length and duration of registration | StablePriceOracle.sol | StablePriceOracle.sol | | Exponential Premium Oracle | A Dutch auction pricing mechanism for fairly pricing names after expiry | ExponentialPremiumPricingOracle.sol | ExponentialPremiumPricingOracle.sol |

In addition to replicating the base behavior of the ENS protocol, we are offering a series of promotional discounts associated with various Coinbase product integrations. As such, the Base Usernames Registrar Controller allows users to perform discounted registrations while passing along integration-specific validationData. Each discount leverages a common interface:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.23;

/// @title Discount Validator Interface
///
/// @notice Common interface which all Discount Validators must implement.
///         The logic specific to each integration must ultimately be consumable as the `bool` returned from
///         `isValidDiscountRegistration`.
interface IDiscountValidator {
    /// @notice Required implementation for compatibility with IDiscountValidator.
    ///
    /// @dev Each implement