masscan

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# MASSCAN: Mass IP port scanner

This is an Internet-scale port scanner. It can scan the entire Internet
in under 5 minutes, transmitting 10 million packets per second,
from a single machine.

Its usage (parameters, output) is similar to `nmap`, the most famous port scanner.
When in doubt, try one of those features -- features that support widespread
scanning of many machines are supported, while in-depth scanning of single
machines aren't.

Internally, it uses asynchronous transmission, similar to port scanners
like  `scanrand`, `unicornscan`, and `ZMap`. It's more flexible, allowing
arbitrary port and address ranges.

NOTE: masscan uses its own **ad hoc TCP/IP stack**. Anything other than
simple port scans may cause conflict with the local TCP/IP stack. This means you 
need to use either the `--src-ip` option to run from a different IP address, or
use `--src-port` to configure which source ports masscan uses, then also
configure the internal firewall (like `pf` or `iptables`) to firewall those ports
from the rest of the operating system.

This tool is free, but consider contributing money to its development:
Bitcoin wallet address: 1MASSCANaHUiyTtR3bJ2sLGuMw5kDBaj4T


# Building

On Debian/Ubuntu, it goes something like the following. It doesn't
really have any dependencies other than a C compiler (such as `gcc`
or `clang`).

	sudo apt-get --assume-yes install git make gcc
	git clone https://github.com/robertdavidgraham/masscan
	cd masscan
	make

This puts the program in the `masscan/bin` subdirectory. 
To install it (on Linux) run:

    make install

The source consists of a lot of small files, so building goes a lot faster
by using the multi-threaded build. This requires more than 2gigs on a 
Raspberry Pi (and breaks), so you might use a smaller number, like `-j4` rather than
all possible threads.

	make -j

While Linux is the primary target platform, the code runs well on many other
systems (Windows, macOS, etc.). Here's some additional build info:

  * Windows w/ Visual Studio: use the VS10 project
  * Windows w/ MinGW: just type `make`
  * Windows w/ cygwin: won't work
  * Mac OS X /w XCode: use the XCode4 project
  * Mac OS X /w cmdline: just type `make`
  * FreeBSD: type `gmake`
  * other: try just compiling all the files together, `cc src/*.c -o bin/masscan`

On macOS, the x86 binaries seem to work just as fast under ARM emulation.

# Usage

Usage is similar to `nmap`. To scan a network segment for some ports:

	# masscan -p80,8000-8100 10.0.0.0/8 2603:3001:2d00:da00::/112

This will:
* scan the `10.x.x.x` subnet, and `2603:3001:2d00:da00::x` subnets
* scans port 80 and the range 8000 to 8100, or 102 ports total, on both subnets
* print output to `<stdout>` that can be redirected to a file

To see the complete list of options, us