MRC 59: MOR Subnet Namespace Smart Contract

1. Overview

The MOR Subnet Namespace is a decentralized system for registering and managing unique subnet names on the Ethereum blockchain. It enables subnets (e.g., decentralized networks, blockchain layers, or applications) to claim human-readable names (e.g., mysubnet.mor) and associate them with metadata, such as an Ethereum address, IPFS hash, or other relevant data. The MOR system is inspired by the Ethereum Name Service (ENS) but is tailored for subnet-specific use cases.

Goals

• Provide a secure, decentralized, and transparent mechanism for registering unique subnet names.

• Ensure names are globally unique and resolvable to associated metadata.

• Support extensible metadata for subnet-specific needs.

• Minimize gas costs for registration and management.

• Enable transferability and expiration of name ownership.

Key Features

• Unique Name Registration: Subnets can register a unique name under the .mor top-level domain.

• Ownership and Transfer: Names are owned by Ethereum addresses, with support for transferring ownership.

• Expiration and Renewal: Names are leased for a defined period and can be renewed.

• Resolver System: Names can resolve to Ethereum addresses, content hashes, or custom metadata.

• Subdomain Support: Owners can create subdomains (e.g., sub.mysubnet.mor).

• Gas Efficiency: Optimized for low-cost interactions on Ethereum.

2. Architecture

The MOR Subnet Namespace system consists of the following core components:

2.1. MOR Subnet Registry

The MOR Subnet Registry is the smart contract that maintains a mapping of names to their owners and associated metadata. It is the single source of truth for name ownership and resolver information.

• Data Structure:

  • Maps a keccak256 hash of the name (e.g., keccak256("mysubnet.mor")) to a record containing:

    • owner: The Ethereum address that owns the name.

    • resolver: The address of the resolver contract (if any).

    • ttl: Time-to-live (expiration timestamp) for the name lease.

    • createdAt: Timestamp of registration.

    • metadata: Optional metadata (e.g., IPFS hash for subnet details).

• Functions:

  • register(bytes32 node, address owner, uint256 duration): Registers a name for a specified duration.

  • setOwner(bytes32 node, address newOwner): Transfers ownership of a name.

  • setResolver(bytes32 node, address resolver): Sets the resolver contract for a name.

  • renew(bytes32 node, uint256 duration): Extends the lease duration of a name.

  • reclaim(bytes32 node): Allows the owner to reclaim an expired name.

  • getRecord(bytes32 node): Retrieves the record for a name.

2.2. Resolver

The Resolver is a contract that resolves a name to specific resources (e.g., an Ethereum address, IPFS hash, or custom data). Each name can have its own resolver contract, or use a default public resolver provided by the MOR Subnet Namespace.

• Standard Resolver Interface (inspired by ENS Resolver):

  interface IResolver {
      function addr(bytes32 node) external view returns (address);
      function contentHash(bytes32 node) external view returns (bytes memory);
      function setAddr(bytes32 node, address addr) external;
      function setContentHash(bytes32 node, bytes memory hash) external;
      function supportsInterface(bytes4 interfaceID) external view returns (bool);
  }
  
  ### Extensibility

Subnets can deploy custom resolvers to support additional data types (e.g., URLs, subnet configurations, or other metadata).

2.3. Registrar

The Registrar is a contract responsible for handling the registration and renewal process for names under the .mor domain. It enforces rules such as name availability, pricing, and lease duration.

Key Features

• Ensures names are unique and not already registered.

• Implements a pricing model (e.g., based on name length or fixed fees).

• Manages lease durations (e.g., 1 year minimum, renewable).

• Supports auctions or first-come-first-serve registration.

Functions

• registerName(string memory name, address owner, uint256 duration): Registers a name under .mor.

• renewName(string memory name, uint256 duration): Renews a name’s lease.

• price(string memory name, uint256 duration): Returns the registration cost.

• available(string memory name): Checks if a name is available.

2.4. Subdomain Support

The mor system supports hierarchical names (subdomains). Owners of a name (e.g., mysubnet.mor) can create subdomains (e.g., node.mysubnet.mor) and assign ownership or resolvers to them.

Subdomain Registry

• Extends the mor Registry with a function to create subdomains:

  function setSubnodeOwner(bytes32 node, bytes32 label, address owner) external;
  
  - `node` is the parent name’s hash (e.g., `keccak256("mysubnet.mor")`).

• label is the subdomain’s hash (e.g., keccak256("node")).

3. Smart Contract Specification

Below is a simplified implementation of the core mor Registry contract, written in Solidity.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract morRegistry {
    struct Record {
        address owner;
        address resolver;
        uint64 ttl;
        uint64 createdAt;
    }

    mapping(bytes32 => Record) public records;
    address public registrar;

    event NameRegistered(bytes32 indexed node, address owner, uint64 ttl);
    event NameTransferred(bytes32 indexed node, address newOwner);
    event ResolverUpdated(bytes32 indexed node, address resolver);

    modifier onlyOwner(bytes32 node) {
        require(records[node].owner == msg.sender, "Not owner");
        _;
    }

    modifier onlyRegistrar() {
        require(msg.sender == registrar, "Not registrar");
        _;
    }

    constructor(address _registrar) {
        registrar = _registrar;
    }

    function register(bytes32 node, address owner, uint64 duration) external onlyRegistrar {
        require(records[node].owner == address(0) || records[node].ttl < block.timestamp, "Name already registered");
        records[node] = Record({
            owner: owner,
            resolver: address(0),
            ttl: uint64(block.timestamp) + duration,
            createdAt: uint64(block.timestamp)
        });
        emit NameRegistered(node, owner, duration);
    }

    function setOwner(bytes32 node, address newOwner) external onlyOwner(node) {
        records[node].owner = newOwner;
        emit NameTransferred(node, newOwner);
    }

    function setResolver(bytes32 node, address resolver) external onlyOwner(node) {
        records[node].resolver = resolver;
        emit ResolverUpdated(node, resolver);
    }

    function renew(bytes32 node, uint64 duration) external onlyRegistrar {
        require(records[node].ttl >= block.timestamp, "Name expired");
        records[node].ttl += duration;
        emit NameRegistered(node, records[node].owner, duration);
    }

    function getRecord(bytes32 node) external view returns (Record memory) {
        return records[node];
    }
}
### Key Notes on Implementation
- **Security**: The contract uses `onlyOwner` and `onlyRegistrar` modifiers to restrict access to sensitive functions.
- **Gas Optimization**: The `Record` struct is packed efficiently to minimize storage costs.
- **Extensibility**: The registry supports custom resolvers and metadata via the `resolver` field.
- **Event Logging**: Events are emitted for all state changes to ensure transparency and auditability.

## 4. Registration Process
The process for registering a subnet name is as follows:

4A. **Check Availability**:
   - The user queries the Registrar contract’s `available` function to verify that the desired name (e.g., `mysubnet.mor`) is not already registered or reserved.

4B. **Calculate Cost**:
   - The user calls the `price` function to determine the registration cost, which may depend on name length, demand, or duration.

4C. **Register Name**:
   - The user submits a transaction to the Registrar contract’s `registerName` function, specifying:
     - The name (e.g., `mysubnet.mor`).
     - The owner’s Ethereum address.
     - The lease duration (e.g., 1 year in seconds).
     - Payment (in ETH) for the registration fee.
   - The Registrar computes the `keccak256` hash of the name and interacts with the mor Registry to create a record.

4D. **Set Resolver**:
   - The owner calls the Registry’s `setResolver` function to assign a resolver contract for the name.
   - The resolver is configured with metadata (e.g., an Ethereum address or IPFS hash).

5. **Resolve Name**:
   - Anyone can query the resolver to retrieve the associated metadata (e.g., `resolver.addr(keccak256("mysubnet.mor"))`).

## 5. Standards and Interoperability
The mor system adheres to Ethereum standards to ensure compatibility and interoperability:

- **EIP-137 (ENS)**: The mor Registry and Resolver are inspired by ENS’s architecture and interface.
- **EIP-181**: Name normalization follows ENS’s rules (e.g., lowercase, no special characters).
- **EIP-165 (Interface Detection)**: Resolvers implement `supportsInterface` to advertise supported features.
- **EIP-712 (Typed Data Signing)**: Optional support for off-chain registration signatures to reduce gas costs.

### Name Normalization
- Names must be lowercase and alphanumeric (e.g., `mysubnet.mor`).
- Invalid characters (e.g., spaces, uppercase) are rejected by the Registrar.
- Minimum name length: 3 characters (excluding `.mor`).
- Maximum name length: 255 characters (including `.mor`).

## 6. Pricing and Economics
- **Registration Fee**: Determined by the Registrar, potentially based on:
  - Name length (e.g., shorter names are more expensive).
  - Fixed fee per year of lease duration.
  - Market demand (e.g., auction for premium names).
- **Renewal Fee**: Similar to registration, but typically lower to incentivize renewals.
- **Revenue**: Fees are collected by the Registrar and may be:
  - Burned (to reduce ETH supply).
  - Sent to a treasury for mor system maintenance.
  - Distributed to stakers or governance (if applicable).

## 7. Security Considerations
- **Front-Running**: Mitigated by requiring a commit-reveal scheme for high-demand names or auctions.
- **Reentrancy**: All state changes follow the Checks-Effects-Interactions pattern.
- **Name Squatting**: Mitigated by lease expirations and renewal incentives.
- **Access Control**: Only the owner or Registrar can modify critical data.
- **Upgradeability**: The Registry can be made upgradeable via a proxy pattern, with governance approval.

## 8. Example Usage

### Registering a Name
```solidity
// User wants to register "mysubnet.mor" for 1 year
Registrar registrar = Registrar(0x...);
string memory name = "mysubnet";
uint256 duration = 365 days;

// Check availability
require(registrar.available(name), "Name not available");

// Calculate cost
uint256 cost = registrar.price(name, duration);

// Register name
registrar.registerName{value: cost}(name, msg.sender, duration);

### Resolving a Name
```solidity
morRegistry registry = morRegistry(0x...);
bytes32 node = keccak256(abi.encodePacked("mysubnet.mor"));

// Get resolver
address resolverAddr = registry.getRecord(node).resolver;
IResolver resolver = IResolver(resolverAddr);

// Resolve to address
address subnetAddr = resolver.addr(node);

## 9. Future Extensions
- **Governance**: Introduce a DAO to manage Registrar policies (e.g., pricing, reserved names).
- **Multi-Chain Support**: Extend mor to Layer 2 solutions or other EVM-compatible chains.
- **Premium Names**: Implement auctions for high-value names (e.g., `node.mor`, `chain.mor`).
- **Integration with DeFi**: Allow names to be used as collateral or in NFT marketplaces.
- **Off-Chain Resolution**: Support DNS-like resolution for broader adoption.

## 10. Conclusion
The MOR Subnet Namespace (.MOR extension) provides a robust, decentralized solution for registering unique subnet names on Ethereum, drawing heavily from the ENS standard. By combining a simple registry, flexible resolvers, and a modular registrar, MOR Subnet names enables subnets to establish a recognizable identity on the blockchain while maintaining security, extensibility, and interoperability.

This specification can be implemented as a starting point and extended based on specific subnet requirements or community governance.