robertdavidgraham/masscan
Masscan
Masscan is a command-line network scanner designed for large-scale discovery and infrastructure reconnaissance. It identifies open ports across specific network segments or the entire internet by probing vast address ranges with high efficiency. The tool functions as an asynchronous packet engine, bypassing standard operating system kernel networking stacks to transmit raw packets directly from application memory.
The project distinguishes itself through a specialized architecture that manages millions of concurrent connections by separating packet transmission and reception into independent execution threads. It utilizes a stateless, index-based mathematical algorithm to randomize target selection, ensuring probes are distributed unpredictably across address spaces. To maintain consistent performance and prevent network congestion, the scanner employs a high-precision timer to regulate transmission rates and uses zero-copy buffer management to minimize memory overhead.
The software provides a platform-agnostic interface for raw network access, allowing it to operate consistently across different hardware and operating system environments. It supports the export of collected reconnaissance data into structured formats such as XML, JSON, or plain text for further analysis. The application is distributed as a portable utility, with its core codebase maintained through standardized string handling and automated testing.
Features
- Network Discovery Tools - Scans massive address ranges to identify active devices and open services with high efficiency.
- Packet Engines - Manages millions of concurrent connections by bypassing standard operating system drivers for maximum throughput.
- Port Scanners - Identifies open ports across specific network segments by defining target IP ranges and port numbers.
- High-Concurrency Networking - Manages millions of simultaneous connections by bypassing standard system drivers.
- Network Scanners - Probes large network address spaces and port ranges at high speeds using custom packet injection techniques.
- Packet Injection Engines - Sends network traffic at extreme speeds by bypassing standard operating system networking stacks.
- Kernel Networking - Bypasses the operating system kernel networking stack to transmit raw packets directly from application memory.
- Asynchronous Networking - Separates packet transmission and reception into independent threads to maximize concurrent network operations.
- Asynchronous Scanners - Organizes scanning tasks using independent threads for sending and receiving data to maximize performance.
- Security Auditing Tools - Identifies potential vulnerabilities by systematically probing for open ports and services.
- Security Reconnaissance Tools - Provides a portable command-line interface for consistent security reconnaissance and transmission rate management across hardware platforms.
- Zero-Copy Buffers - Minimizes memory overhead by reusing pre-allocated packet structures to handle millions of simultaneous connections.
- Command Line Tools - Listed in the “Command Line Tools” section of the The Book Of Secret Knowledge awesome list.
- Port Scanning - Asynchronous TCP port scanner for internet-wide scanning.
- Reconnaissance Tools - High-speed TCP port scanner.
- Network Reconnaissance - Performs high-speed port scanning across large IP ranges.
- Network Reconnaissance Tools - High-speed TCP port scanner for large networks.
- Network Scanning - High-speed TCP port scanner for large networks.
- Network Security - High-speed IP and TCP port scanner.
- Security & Privacy - High-speed port scanner for network security analysis.
- Traffic Rate Limiters - Regulates packet output frequency using high-precision timers to maintain consistent scanning speeds.
- Transmission Rate Controllers - Adjusts the packet sending rate to maintain high performance while preventing network congestion.
- Infrastructure Reconnaissance Tools - Collects and exports network data to facilitate the analysis of large-scale environments.
- Network Target Selection - Selects target IP addresses and ports using an efficient index-based algorithm for balanced scanning patterns.
- Randomized Probing Algorithms - Maps massive address ranges to randomized sequences using stateless mathematical algorithms for efficient scanning.
- Network Monitoring Tools - Tracks network state through independent threads without locking system resources.
