#port-scanner #connectivity #scanner

app port_cat

A simple CLI tool to test connectivity to or scan ports on a remote host

1 unstable release

Uses new Rust 2024

0.1.0 Sep 24, 2025

#699 in Network programming

MIT license

18KB
312 lines

Port Cat 🐱

A fast and efficient CLI tool for testing network connectivity and scanning ports on remote hosts, written in Rust.

Features

  • Connection Testing: Test connectivity to specific ports
  • Port Scanning: Scan port ranges with concurrent execution
  • Service Detection: Automatically detect running services (HTTP, SSH, databases, etc.)
  • Async Performance: High-performance concurrent scanning using Tokio
  • Detailed Logging: Configurable log levels for debugging

Installation

From Source

git clone https://github.com/yourusername/port_cat.git
cd port_cat
cargo build --release

The binary will be available at target/release/port_cat

Using Cargo

cargo install --path .

Usage

Basic Connection Testing

Test connectivity to specific ports:

# Test default ports (80, 443) on localhost
port_cat

# Test specific host and ports
port_cat example.com -p 22,80,443

# Test with custom timeout
port_cat example.com -p 22 -t 10

Port Range Scanning

Scan a range of ports:

# Scan ports 1-1000
port_cat example.com -s 1-1000

# Scan common ports
port_cat example.com -s 1-65535

Service Detection

The tool automatically detects services running on open ports:

Connected to example.com:22 - Service: SSH
Connected to example.com:80 - Service: HTTP (Nginx)
Connected to example.com:443 - Service: HTTPS
Connected to example.com:3306 - Service: MySQL

Supported service detection:

  • Web Services: HTTP, HTTPS (with server detection: Nginx, Apache, IIS, Caddy)
  • SSH: Secure Shell
  • Databases: MySQL, PostgreSQL, Redis, MongoDB
  • Mail Services: SMTP, POP3, IMAP
  • FTP: File Transfer Protocol
  • And more...

Command Line Options

USAGE:
    port_cat [OPTIONS] [HOST]

ARGS:
    <HOST>    Host to connect to [default: localhost]

OPTIONS:
    -p, --port <PORT>           Port numbers (comma-separated) [default: 80,443]
    -s, --scan <RANGE>          Scan mode with port range (e.g., 1-1000)
    -t, --timeout <TIMEOUT>     Timeout in seconds [default: 5]
        --debug-level <LEVEL>   Log level [default: info] [possible values: error, warn, info, debug, trace]
    -h, --help                  Print help
    -V, --version               Print version

Examples

Test Web Services

# Test if a website is accessible
port_cat google.com -p 80,443

Database Connectivity

# Test database connections
port_cat db.example.com -p 3306,5432,6379

Port Scanning

# Quick scan of common ports
port_cat target.com -s 1-1024

# Scan with debug output
port_cat target.com -s 20-25 --debug-level debug

SSH Connection Test

# Test SSH connectivity
port_cat server.example.com -p 22

Performance

Port Cat is designed for speed and efficiency:

  • Concurrent Scanning: Multiple ports scanned simultaneously using async/await
  • Fast Service Detection: Protocol-specific probes for accurate service identification
  • Configurable Timeouts: Adjust timeout values for different network conditions
  • Low Resource Usage: Efficient memory and CPU utilization

Service Detection Technology

The tool uses multiple detection methods:

  1. Banner Reading: Captures service banners automatically sent by servers
  2. Protocol Probing: Sends protocol-specific requests (HTTP, database handshakes, etc.)
  3. Response Analysis: Analyzes server responses to identify specific services and versions

Contributing

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

License

This project is licensed under the MIT License - see the LICENSE file for details.

Dependencies

~3.5–7.5MB
~132K SLoC