Binary search MTU discovery - Efficiently find the maximum MTU size
Common MTU testing - Test standard MTU sizes (68, 576, 1280, 1500, 4464, 9000)
Custom range testing - Test specific MTU ranges
IPv4 and IPv6 support - MTU discovery for both IP versions

DNS Testing

Comprehensive record types - A, AAAA, MX, NS, TXT, CNAME, SOA, PTR, and more
Multiple DNS servers - Test against Google, Cloudflare, Quad9, OpenDNS, and others
TCP and UDP queries - Support for both DNS transport protocols
Large query testing - Test handling of large DNS responses
International domains - Support for IDN (Internationalized Domain Names)

Domain Category Testing

Normal websites - Test legitimate, commonly used sites
Ad networks - Test advertising and tracking domains
Spam domains - Test temporary email and spam-associated domains
Adult content - Test adult content sites (often filtered)
Malicious domains - Test known malicious/phishing domains
Social media - Test major social media platforms
Streaming services - Test video and music streaming sites
Gaming platforms - Test gaming services and platforms
News websites - Test major news and media sites

DNS Filtering Analysis

Filter effectiveness - Analyze how well DNS filtering is working
Category-based analysis - See which categories are being blocked
Detailed reporting - Get statistics on resolution success rates

Installation

# Clone the repository
git clone <repository-url>
cd nettest

# Build the project
cargo build --release

# Install globally (optional)
cargo install --path .

Usage

Basic Commands

# Run comprehensive tests on a target
nettest full google.com

# Test TCP connectivity
nettest network tcp google.com --port 80

# Test UDP connectivity  
nettest network udp 8.8.8.8 --port 53

# Ping test
nettest network ping google.com --count 4

# Test common ports
nettest network ports google.com --protocol tcp

# DNS query
nettest dns query google.com --record-type a

# Test DNS servers
nettest dns servers google.com

# Test domain categories
nettest dns categories --category normal

# MTU discovery
nettest mtu discover google.com

# Test common MTU sizes
nettest mtu common google.com

Advanced Options

# Specify IP version
nettest network tcp google.com --ip-version v4
nettest network tcp google.com --ip-version v6
nettest network tcp google.com --ip-version both

# Custom timeout
nettest --timeout 10 network tcp google.com

# JSON output
nettest --json dns query google.com

# Verbose logging
nettest --verbose full google.com

# DNS query with specific server
nettest dns query google.com --server 8.8.8.8:53 --tcp

# Custom MTU range
nettest mtu range google.com --min 1000 --max 1500

Domain Category Testing

Test different categories of domains to analyze DNS filtering:

# Test normal websites
nettest dns categories --category normal

# Test ad networks
nettest dns categories --category ads

# Test all categories
nettest dns categories --category all

# DNS filtering effectiveness
nettest dns filtering

Comprehensive Testing

The full command runs a comprehensive suite of tests:

# Full test suite for a domain
nettest full example.com

# Full test with specific IP version
nettest full example.com --ip-version v4

This includes:

TCP and UDP connectivity tests
ICMP ping tests
MTU discovery
DNS resolution tests
DNS server tests

Output Formats

Human-readable (default)

Colored, formatted output suitable for terminal viewing.

JSON

Machine-readable JSON output for integration with other tools:

nettest --json dns query google.com

Requirements

Rust 1.70 or later
Root/administrator privileges may be required for:
- ICMP ping tests
- Raw socket operations
- MTU discovery

Testing

Run the test suite:

# Unit tests
cargo test

# Integration tests
cargo test --test integration_tests

# All tests with verbose output
cargo test -- --nocapture

Architecture

The tool is organized into several modules:

cli - Command-line argument parsing and interface
network - TCP, UDP, and ICMP connectivity testing
dns - DNS resolution and query testing
mtu - MTU discovery and testing
utils - Common utilities and error handling

Security Considerations

This tool is designed for defensive security testing and network diagnostics. It:

Tests legitimate connectivity to verify network functionality
Analyzes DNS filtering effectiveness
Discovers network path characteristics
Does not attempt to exploit or attack systems
Respects rate limits and timeouts

License

[Add your license here]

Contributing

[Add contribution guidelines here]