DeviceId

A simple library providing functionality to generate a 'device ID' that can be used to uniquely identify a computer.

Quickstart

Building a device identifier

Use the DeviceIdBuilder class to build up a device ID.

string deviceId = new DeviceIdBuilder()
    .AddMachineName()
    .AddProcessorId()
    .AddMotherboardSerialNumber()
    .AddSystemDriveSerialNumber()
    .ToString();

What can you include in a device identifier

The following extension methods are available out of the box to suit some common use cases:

• AddUserName() adds the current user's username to the device ID.
• AddMachineName() adds the machine name to the device ID.
• AddOSVersion() adds the current OS version (as returned by Environment.OSVersion) to the device ID.
• AddMacAddress() adds the MAC address to the device ID.
• AddProcessorId() adds the processor ID to the device ID.
• AddMotherboardSerialNumber() adds the motherboard serial number to the device ID.
• AddSystemDriveSerialNumber() adds the system drive's serial number to the device ID.
• AddSystemUUID() adds the system UUID to the device ID.
• AddOSInstallationID adds the OS installation ID.
• AddFileToken(path) adds a token stored at the specified path to the device ID.
• AddRegistryValue() adds a value from the registry.
• AddComponent(component) adds a custom component (see below) to the device ID.

Custom components can be built by implementing IDeviceIdComponent. There is also a simple DeviceIdComponent class that allows you to specify an arbitrary component value to use, and a WmiDeviceIdComponent class that uses a specified WMI property (example: new WmiDeviceIdComponent("MACAddress", "Win32_NetworkAdapterConfiguration", "MACAddress").

Dealing with MAC Address randomization and virtual network adapters

Non physical network adapters like VPN connections tend not to have fixed MAC addresses. For wireless (802.11 based) adapters hardware (MAC) address randomization is frequently applied to avoid tracking with many modern operating systems support this out of the box. This makes wireless network adapters bad candidates for device identification.

Use AddMacAddress(true, true) to exclude both virtual and wireless network adapters.

Controlling how the device identifier is formatted

Use the UseFormatter method to set the formatter.

string deviceId = new DeviceIdBuilder()
    .AddProcessorId()
    .AddMotherboardSerialNumber()
    .UseFormatter(new HashDeviceIdFormatter(() => SHA256.Create(), new Base64UrlByteArrayEncoder()))
    .ToString();

You can use one of the out-of-the-box implementations of IDeviceIdFormatter in the DeviceId.Formatters namespace, or you can create your own.

• StringDeviceIdFormatter - Formats the device ID as a string containing each component ID, using any desired component encoding.
• HashDeviceIdFormatter - Formats the device ID as a hash string, using any desired hash algorithm and byte array encoding.
• XmlDeviceIdFormatter - Formats the device ID as an XML document, using any desired component encoding.

There are a number of encoders that can be used customize the formatter. These implement IDeviceIdComponentEncoder and IByteArrayEncoder and are found in the DeviceId.Encoders namespace.

• PlainTextDeviceIdComponentEncoder - Encodes a device ID component as plain text.
• HashDeviceIdComponentEncoder - Encodes a device ID component as a hash string, using any desired hash algorithm.
• HexByteArrayEncoder - Encodes a byte array as a hex string.
• Base64ByteArrayEncoder - Encodes a byte array as a base 64 string.
• Base64UrlByteArrayEncoder - Encodes a byte array as a base 64 url-encoded string.

Cross-platform support

The following cross-platform support is available:

Component	Windows	Linux	OSX
User name	Yes	Yes	Yes
Machine name	Yes	Yes	Yes
OS version	Yes	Yes	Yes
Processor ID	Yes	Yes	Yes*
MAC address	Yes	Yes	Yes
Motherboard serial number	Yes	Yes	No
System drive serial number	Yes	Yes	Yes
System UUID	Yes	Yes	No
OS installation ID	Yes	Yes	No
Registry value	Yes	No	No
File token	Yes	Yes	Yes

* OSX Processor ID is Apple Serial Number

Installation

Just grab it from NuGet

PM> Install-Package DeviceId

$ dotnet add package DeviceId

Strong naming

From version 5 onwards, the assemblies in this package are strong named for the convenience of those users who require strong naming. Please note, however, that the key files are checked in to this repository. This means that anyone can compile their own version and strong name it with the original keys. This is a common practice with open source projects, but it does mean that you shouldn't use the strong name as a guarantee of security or identity.

License and copyright

Copyright Matthew King 2015-2020. Distributed under the MIT License. Refer to license.txt for more information.