MyDNS

MyDNS is a lightweight DNS server implementation written in Go, following the RFC-1035 specification. It features an efficient event-loop architecture for handling high query loads and supports basic DNS functionalities with domain blocking capabilities.

Features

• High Performance: Implements an event-loop architecture with worker pools for concurrent DNS query processing
• DNS Query Support: Currently handles A record queries, supporting both IPv4 and IPv6 responses
• Domain Management:
  • Block unwanted domains using blacklist
  • Custom domain resolution via known_hosts configuration
• Caching Layer: Optional Redis integration for improved response times
• Cross-Platform: Thanks to Go compiler, supports multiple platforms including:
  • Linux (amd64, arm64)
  • macOS (amd64)
  • Windows (amd64)
• Load Balancing: [Planned] Round-robin distribution of DNS queries across worker pools

Requirements

• Go 1.16 or later
• Redis 6.0 or later (optional)

Installation

1. Clone the repository:

git clone https://github.com/darwineee/MyDNS.git
cd mydns

2. Build the application:

# Build for current platform
make build

# Build for all supported platforms
make build-all

The executable files will be generated in the bin directory.

Configuration

Config File (config.yaml)

Create a config.yaml file in the root directory. Example configuration:

# Redis configuration
redis:
  host: "127.0.0.1:6379"
  password: "admin"
  db: 0

# UDP configuration
udp:
  pkg_limit_rfc1035: 512
  pkg_limit_edns0: 4096

# Server configuration
server:
  port: 2053
  protocol: "udp"
  event_queue_size: 1000
  event_queue_timeout_milliseconds: 500
  cache_ttl_seconds: 300
  blacklist_file_path: "blacklist-example"
  known_hosts_file_path: "known_hosts-example"

Known Hosts File

Create a known_hosts file to define custom domain resolutions. Example:

# Format: domain IP_address
# Example:
darwindev.direkt.app 51.79.147.45

Blacklist File

Create a blacklist file to block specific domains. Example:

# One domain per line
blocked-domain.com
unwanted-site.net

Usage

1. Start the server:

make run

2. The server will listen on port 2053 (UDP) by default.

3. To stop the server, press Ctrl + C or type stop (currently the only supported command).

Testing

You can test the DNS server using the dig command on Linux:

# Test a domain resolution
dig @localhost -p 2053 example.com A

# Test a known host
dig @localhost -p 2053 darwindev.direkt.app A

# Test a blacklisted domain
dig @localhost -p 2053 blocked-domain.com A

Planned Features

• Multiple IP Support: Allow multiple IP addresses per domain in known_hosts file

  # Example future format:
  darwindev.direkt.app 51.79.147.45 123.222.34.1 1.1.1.1
  

• Extended Query Types: Support for additional DNS query types beyond A records

• Command Interface: Expanded command support beyond 'stop'

  • Status monitoring
  • Configuration reload
  • Cache management
  • Statistics viewing

• Load Balancing: Round-robin distribution for domains with multiple IPs

Architecture

                           Local Host          |    Foreign
                                              |
+---------+               +----------+         |  +--------+
|         | user queries  |          |queries  |  |        |
|  User   |-------------->|          |---------|->| Foreign|
| Program |               |  MyDNS   |         |  |  Name  |
|         |<--------------|          |<--------|--| Server |
|         | user responses|          |responses|  |        |
+---------+               +----------+         |  +--------+
                            |     A            |
            cache additions |     | references |
                            V     |            |
                          +----------+         |
                          |  Redis   |         |
                          +----------+         |

The application implements a high-performance event loop design:

• Request Handler processes incoming DNS queries
• Queue system manages query distribution
• Worker pool handles concurrent query processing
• Optional Redis caching layer for improved performance

Development

This project implements the DNS protocol according to RFC-1035 specifications. The main components include:

• DNS message parsing and encoding
• Query processing and resolution
• Cache management
• Concurrent request handling

License

MIT License

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.