arpping

Discover and search for internet-connected devices (locally) using ping and arp

Usage no npm install needed!

<script type="module">
  import arpping from 'https://cdn.skypack.dev/arpping';
</script>

README

arpping

Discover and search for internet-connected devices (locally) using ping and arp

Motivation

I was trying to find a quick and reliable way to ping and discover devices connected to my LAN. I tried out:

But both node-nmap and libnmap were slow and unreliable, and node-arp only had part of the functionality I needed, so I decided to make my own. This is the result, and it's been pretty helpful so far.

Installation

Using npm:

$ npm install --save arpping

Usage

To include in a project file:

const Arpping = require('arpping');
const arpping = new Arpping(options);

The module returns the Arpping class. The Arpping constructor accepts an optional object argument with the following parameters:

Parameter Default Description
timeout 5 The time, in seconds, ping will try to send packets to a device before returning results
includeEndpoints false Specify if you'd like to include range endpoints (1, 255) in your scans
useCache true Specify if you'd like to temporarily cache results for quicker and convenient usage
cacheTimeout 3600 Specify the cache's TTL (time to live) in seconds
interfaceFilters {} Filters for specifying which network interface to connect to - valid filters are explained below
connectionInterval 600 The time interval, in seconds, for testing device's connection
onConnect [] An array of callback functions to be called when a new connection is established
onDisconnect [] An array of callback functions to be called when an existing connection is no longer active
debug false Enable/disable debug logging

Interface

Interfaces represent different network types, e.g. Ethernet, WiFi, self-hosted networks (hotspots). Each Arpping instance connects to one (and only one) of these network interfaces and is able to search and discover other devices on that network. Valid filters are arrays that specify valid values for each interface property. They include:

Filter Default Description
interface [ 'lo0', 'en0', 'eth0', 'wlan0' ] Allowed network interface names
internal [ false ] I think this should only ever be [ false ] as I don't believe external devices can connect to internal networks, but I left it as an option just in case
family [ IPv4 ] specify IPv4 and/or IPv6 network protocol

Note: an empty array means any value is acceptable

myDevice

An Arpping instance has the property myDevice, which lists the interpreted OS of the host machine (instance.myDevice.os).

On initialization, the Arpping instance will try to connect to the first network interface that satisfies the provided filters. If a valid connection is found, myDevice will also contain the device type based on its mac address (if it exists) and connection information, including the IP address, mac address, netmask, and IPv4/IPv6 family.

getNetworkInterfaces Static Method

The Arpping class has a static method called getNetworkInterfaces, which simply wraps the os module's networkInterfaces function, returning an object of available interfaces.

const Arpping = require('arpping');
const arpping = new Arpping(options);

arpping.getNetworkInterfaces();

/* Example output
{
    lo: [
        {
            address: '127.0.0.1',
            netmask: '255.0.0.0',
            family: 'IPv4',
            mac: '00:00:00:00:00:00',
            internal: true,
            cidr: '127.0.0.1/8'
        },
        {
            address: '::1',
            netmask: 'ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff',
            family: 'IPv6',
            mac: '00:00:00:00:00:00',
            scopeid: 0,
            internal: true,
            cidr: '::1/128'
        }
    ],
    eth0: [
        {
            address: '192.168.1.108',
            netmask: '255.255.255.0',
            family: 'IPv4',
            mac: '01:02:03:0a:0b:0c',
            internal: false,
            cidr: '192.168.1.108/24'
        },
        {
            address: 'fe80::a00:27ff:fe4e:66a1',
            netmask: 'ffff:ffff:ffff:ffff::',
            family: 'IPv6',
            mac: '01:02:03:0a:0b:0c',
            scopeid: 1,
            internal: false,
            cidr: 'fe80::a00:27ff:fe4e:66a1/64'
        }
    ]
}
*/

Methods

Any methods that depend on ping/arp (and therefore an active internet/interface connection) will throw an error if no connection is available.

getConnection

This method finds a valid interface connection based on the provided interfaceFilters. It sets the myDevice.connection property and returns it. It is run on initialization, and on an interval based on the connectionInterval parameter. You likely won't need to call this method manually.

Also, depending on the previous and current connection state, the onConnect or onDisconnect callbacks may fire. The onConnect callbacks will be passed the connection object.

const Arpping = require('arpping');
const arpping = new Arpping({
    onConnect: [ connection => console.log(`Connected: ${JSON.stringify(connection, null, 4)}`) ]
});

const connection = arpping.getConnection({ interface: [ 'en0' ], internal: [ false ], family: [] });

/* Example output
Connected: {
    name: 'en0',
    address: '192.168.1.108',
    netmask: '255.255.255.0',
    family: 'IPv4',
    mac: '01:02:03:0a:0b:0c',
    internal: false,
    cidr: '192.168.1.108/24'
}
*/

discover

The discover method returns an array of hosts found on the local network. Each host entry contains the host's ip and mac address, and can also be assigned a type based on its mac address VendorID. The host entry that represents the machine running the script will have a isHostDevice key set with a value of true.

const Arpping = require('arpping');
const arpping = new Arpping(options);

arpping.discover()
    .then(hosts => console.log(JSON.stringify(hosts, null, 4)))
    .catch(err => console.log(err));

/* Example output
[
    {
        "ip": "192.168.0.3",
        "mac": "01:01:01:01:01:01",
        "type": null
    },
    {
        "ip": "192.168.0.12",
        "mac": "99:01:99:01:99:01",
        "type": null
    },
    {
        "ip": "192.168.0.20",
        "mac": "01:23:45:67:89:01",
        "type": "RaspberryPi",
        "isYourDevice": true
    }
]
*/

search

The search functionality is broken up into three methods. For each, you may pass a reference IP address as the second argument to override the default behavior.

searchByIpAddress

Searching by ip address runs a discovery scan and filters the result based on an input array of desired ip addresses. The Promise resolves an object with an array of found hosts and an array of missing ips.

const Arpping = require('arpping');
const arpping = new Arpping(options);

const ipArray = [
    "192.168.0.3",
    "192.168.0.12",
    "192.168.0.24"
];
arpping.searchByIpAddress(ipArray)
    .then(({ hosts, missing }) => {
        console.log(`${hosts.length} host(s) found:\n${JSON.stringify(hosts, null, 4)}`);
        console.log(`${missing.length} host(s) missing:\n${missing}`);
    })
    .catch(err => console.log(err));

/* Example output
2 out of 3 host(s) found:
[
    {
        "ip": "192.168.0.3",
        "mac": "01:01:01:01:01:01",
        "type": null
    },
    {
        "ip": "192.168.0.12",
        "mac": "01:01:01:99:99:99",
        "type": null
    }
]
1 out of 3 host(s) not found:
["192.168.0.24"]
*/
searchByMacAddress

Searching by mac address functions similarly to the byIpAddress method, with the notable additional ability to search by partial mac addresses (i.e. "01:23:45:67:89:10" which only matches one device vs "01:23:45" which may match multiple devices). Each device found will have a matched array specifying the corresponding searched mac address(es). Again, the Promise resolves an object with an array of found hosts and an array of missing search terms.

const Arpping = require('arpping');
const arpping = new Arpping(options);

const macArray = [
    "01:01:01",
    "01:01:01:99:99:99",
    "7f:54:12"
];
arpping.searchByMacAddress(macArray)
    .then(({ hosts, missing }) => {
        console.log(`${hosts.length} matching host(s) found:\n${JSON.stringify(hosts, null, 4)}`);
        console.log(`The following search term(s) returned no results:\n${missing}`);
    })
    .catch(err => console.log(err));

/* Example output
2 matching host(s) found:
[
    {
        "ip": "192.168.0.3",
        "mac": "01:01:01:01:01:01",,
        "type": null
        "matched": [
            "01:01:01"
        ]
    },
    {
        "ip": "192.168.0.12",
        "mac": "01:01:01:99:99:99",,
        "type": null
        "matched": [
            "01:01:01",
            "01:01:01:99:99:99"
        ]
    }
]
The following search term(s) returned no results:
["7f:54:12"]
*/
searchByMacType

Searching by mac type returns all devices that are assigned the specified mac type/vendor (note: my mac address lookup table is painfully sparse)

const Arpping = require('arpping');
const arpping = new Arpping(options);

const type = 'RaspberryPi';
arpping.searchByMacType(type)
    .then(hosts => console.log(`${hosts.length} host(s) found with type: ${type}\n${JSON.stringify(hosts, null, 4)}`))
    .catch(err => console.log(err));

/* Example output
1 host(s) found with type: RaspberryPi
[
    {
        "ip": "192.168.0.20",
        "mac": "01:23:45:67:89:01",
        "type": "RaspberryPi",
        "isYourDevice": true
    }
]
*/

ping

The ping method pings a given array of ip addresses (or the full ip range) and returns an array of hosts that respond as well as an array of those missing hosts that do not

const Arpping = require('arpping');
const arpping = new Arpping(options);

const ipArray = null; // set to null to scan the full ip range
arpping.ping(ipArray)
    .then(({ hosts, missing }) => console.log(`${hosts.length} host(s) found:\n${hosts}`))
    .catch(err => console.log(err));

/* Example output
3 host(s) found:
["192.168.0.3", "192.168.0.12", "192.168.0.20"]
*/

arp

The arp method arps a given array of ip addresses and returns an array of hosts that respond as well as an array of missing hosts that do not

const Arpping = require('arpping');
const arpping = new Arpping(options);

// must specify an array, unlike ping
const ipArray = [
    "192.168.0.3", 
    "192.168.0.12", 
    "192.168.0.24"
];
arpping.ping(ipArray)
    .then(({ hosts, missing }) => {
        console.log(`${hosts.length} matching host(s) found:\n${JSON.stringify(hosts, null, 4)}`);
        console.log(`The following ip address(es) returned no results:\n${missing}`)
    })
    .catch(err => console.log(err));

/* Example output
2 host(s) found:
[
    {
        "ip": "192.168.0.3",
        "mac": "01:01:01:01:01:01",
        "type": null
    },
    {
        "ip": "192.168.0.12",
        "mac": "01:01:01:99:99:99",
        "type": null
    }
]
The following ip address(es) returned no results:
["192.168.0.24"]
*/

Updates

  1. Build out vendorID lookup table, or find some third-party version to include in project
  2. Allow for more customization - custom ip ranges to scan, enable/disable scanning of xxx.xxx.x.1,255, etc.
  3. Other stuff I haven't thought of yet
  4. ???
  5. Profit

Contributing

I made this module on my own. Any help/feedback is appreciated.