This code is a Node.js script that performs network-related tasks,...

August 30, 2025 at 09:27 PM

var fs = require("fs"),
	exec = require("child_process").exec,
	platform = process.platform,
	interface = process.argv[2];

function interfaceChecker(callback){
	if(interface == undefined){
		log("auto detecting interface...")
		var interfaces = ["wlan0", "eth0", "en0", "wlan1", "en1"];
		exec("ifconfig", function(err, stdout, stderr){
			var i = 0;
			function next(){
				if(stdout.match(interfaces[i])){
					interface = interfaces[i];
					callback()
				}else if(i == interfaces.length){
					log("auto-detection failed.", "error");
				}else{
					i += 1;
					next()
				}
			};
			next();		
		})
	}else{
		callback();
	}
}

function log(text, type){
	var io = {
		log: function(){
			console.log("*    "+text);
		},
		error: function(){
			console.log("!!   "+text);
		}
	};
	if(io[type] == undefined){type = "log"};
	io[type]();
}

var commands = {
	changeMAC: {
		linux: "ifconfig {{interface}} down;"+
			   "ifconfig {{interface}} hw ether {{MAC}};"+
			   "ifconfig {{interface}} up;",
		darwin: "ifconfig {{interface}} ether {{MAC}}"
	}	
}
function command(name, vars){
	var s = commands[name][platform]
	for(i in vars){
		s = s.replace("{{"+i+"}}", vars[i])
	}
	return s;
}
function getNodes(callback){
	console.log("*    getting all network nodes...")
	exec("fing -r 1 -o table,csv,nodes.csv", function(err, stdout, stderr){
		if(err || stderr){
			console.log("!!   error at execution:");
			if(err) console.log(err);
			if(stderr) console.log(stderr);
		}else{
			var NumOfNodes = /has ([1-9]*)/g.exec(stdout).index;
			console.log("*    "+NumOfNodes+" are up");
			console.log("*    reading output file")
			fs.readFile("nodes.csv", "utf8", function(err, data){
				if(err) {
					console.log("!!   error at opening nodes.csv:"+err);
				}else{
					console.log("*    parsing output")
					data = data.split("\n");
					var output = []
					for(var i = 0; i < data.length; i++){
						data[i] = data[i].split(";");
						output.push(data[i][5])
						if(i+1 == data.length){
							callback(output);
						}
					}
				}
			})
		}
	});
};
function tryMacs(macs){
	var i = 0;
	function next(mac){
		console.log("*    changing MAC-Address...")
		exec(command("changeMAC", {interface: interface, MAC: mac}), function(err, stdout, stderr){
			console.log("*    waiting for connect...")
			setTimeout(function(){
				console.log("*    getting google.com...")
				exec("curl google.com", function(err, stdout, stderr){
					if(stdout){
						console.log("*    ,-)")
						console.log("*    it's working !!!!");
						console.log("*    using "+mac);
					}else{
						console.log("*    :-(")
						console.log("*    address not working\n*    trying next one")
						next(macs[++i]);
					}
				})
			}, 10000)
		})
	}
	next(macs[i])
}
(function(){
	if(process.env.SUDO_USER || process.env.USER === "root"){
		interfaceChecker(function(){
			getNodes(tryMacs);
		});
	}else{
		console.log("*   you need to be root to exec this. \n*   Try sudo [the command]")
	}
})()

This code is a Node.js script that performs network-related tasks, including auto-detecting a network interface, gathering information about network devices, and attempting to spoof (change) the MAC address of the detected network interface to different values. Here's a high-level explanation of what it does:

1. Initialize Required Modules

The script uses fs (for file operations) and child_process (to execute system commands).
The process.platform is used to determine the operating system (e.g., Linux or macOS).
The network interface to use is optionally passed as a command-line argument.

2. Auto-Detect Network Interface

If no network interface is passed as an argument, the script attempts to auto-detect the active interface by checking common names such as wlan0, eth0, en0, etc., in the output of the ifconfig command.
If a match is found, it sets the interface variable to the detected one.

3. Retrieve Network-Connected Devices

Uses the fing command-line tool (if installed) to scan the local network. It saves a CSV file (nodes.csv) containing information about discovered devices.
Parses the nodes.csv file and extracts data (e.g., MAC addresses) to use in further operations.

4. Change MAC Address

Defines MAC address-changing commands for Linux and macOS systems, using the ifconfig tool.
A command function dynamically generates the appropriate system command for MAC address changes based on the operating system and provided variables (e.g., the interface name and MAC address).

5. Test New MAC Addresses

Attempts to change the MAC address of the detected network interface to each of the MAC addresses found in the nodes.csv file.
After changing the MAC address, it waits 10 seconds for the network to reconnect.
Tests the connectivity of the new MAC address by attempting to access google.com using the curl command.
If connectivity is successful, it logs confirmation that the new MAC address works. If it fails, it moves on to the next MAC address.

6. Execution Flow

The script starts by checking if the user has root privileges (required for changing network settings).
If the user is root, it calls interfaceChecker() to determine the network interface.
On success, it retrieves all network devices using getNodes(), then attempts to spoof and verify the MAC addresses found (tryMacs()).

Key Points

Dependency on External Tools: The script relies on the system tools ifconfig and curl, as well as the third-party fing command-line tool.
Privileges Required: The script must be run as root (or with sudo) because changing network settings requires administrative privileges.
Potential Use Cases:
- Security testing: Verifying how a network responds to different devices.
- MAC address spoofing: Often used to bypass MAC address filtering or for anonymity.
- Network analysis: Enumerating devices on a network.

Risks and Caution

Potential Misuse: This script can be used for malicious activities such as impersonating other devices on a network or bypassing restrictions. Ensure it is used only for ethical purposes.
Platform-Specific Behavior: It only supports Linux and macOS (via process.platform checks for generating ifconfig commands).
Error Handling: While there is some handling of errors (e.g., stderr), execution may fail if some tools (like fing) are not installed.

Summary

This script identifies network-connected devices, extracts their MAC addresses, and tests these addresses by spoofing the current device's MAC. It is primarily focused on system commands for managing network interfaces and testing connectivity.

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