SimpleOTP

.NET library for TOTP/HOTP implementation on server (ASP.NET) or client (Xamarin) side

Features

• Generate and validate OTP codes
• Support of TOTP (RFC 6238) and HOTP (RFC 4226) algorithms
• Support of HMAC-SHA1, HMAC-SHA256 and HMAC-SHA512 hashing algorithms
• Setup URI parser
• Database-ready configuration models
• Configuration generator for server-side implementation
• QR code generator
• No dependencies

By Mateusz Adamowski, taken with Canon EOS. - Own work, CC BY-SA 1.0, https://commons.wikimedia.org/w/index.php?curid=142232

Usage

Generate code

string sample_config_uri = "otpauth://totp/FoxDev%20Studio:eugene@xfox111.net?secret=ESQVTYRM2CWZC3NX24GRRWIAUUWVHWQH&issuer=FoxDev%20Studio";
OTPConfiguration config = OTPConfiguration.GetConfiguration(sample_config_uri);
// OTPModel { Id = af2358b0-3f69-4dd7-9537-32c07d6663aa, Type = TOTP, IssuerLabel = FoxDev Studio, AccountName = eugene@xfox111.net, Secret = ESQVTYRM2CWZC3NX24GRRWIAUUWVHWQH, Issuer = FoxDev Studio, Algorithm = SHA1, Digits = 6, Counter = 0, Period = 00:00:30 }

OTPCode code = OTPService.GenerateCode(ref config);
// OTPasswordModel { Code = 350386, Expiring = 23-May-21 06:08:30 PM }

Validate code

int codeToValidate = 350386;
bool isValid = OTPService.ValidateCode(codeToValidate, config, TimeSpan.FromSeconds(30)); // True

Generate setup config

OTPConfiguration config = OTPConfiguration.GenerateConfiguration("FoxDev Studio", "eugene@xfox111.net");
// OTPModel { Id = af2358b0-3f69-4dd7-9537-32c07d6663aa, Type = TOTP, IssuerLabel = FoxDev Studio, AccountName = eugene@xfox111.net, Secret = ESQVTYRM2CWZC3NX24GRRWIAUUWVHWQH, Issuer = FoxDev Studio, Algorithm = SHA1, Digits = 6, Counter = 0, Period = 00:00:30 }

Uri uri = config.GetUri();	// otpauth://totp/FoxDev%20Studio:eugene@xfox111.net?secret=ESQVTYRM2CWZC3NX24GRRWIAUUWVHWQH&issuer=FoxDev%20Studio
string qrCode = config.GetQrImage(300); // data:image/png;base64,...

Streamline code generation for client

OTPFactory factory = new (config);

factory.CodeUpdated += (newCode) => Console.WriteLine(newCode);
// OTPasswordModel { Code = 350386, Expiring = 23-May-21 06:08:30 PM }
factory.PropertyChanged += (sender, args) =>
{
	if (args.PropertyName == nameof(factory.TimeLeft))
		Console.WriteLine(factory.TimeLeft);
	else
		Console.WriteLine(factory.Code);
}
...
factory.Dispose();

Download

• NuGet Gallery
• GitHub Releases

Contributing

There are many ways in which you can participate in the project, for example:

• Submit bugs and feature requests, and help us verify as they are checked in
• Review source code changes
• Review documentation and make pull requests for anything from typos to new content

If you are interested in fixing issues and contributing directly to the code base, please see the Contribution Guidelines, which covers the following:

• How to deploy the extension on your browser
• The development workflow, including debugging and running tests
• Coding guidelines
• Submitting pull requests
• Finding an issue to work on
• Contributing to translations

Code of Conduct

This project has adopted the Contributor Covenant. For more information see the Code of Conduct

Copyrights

©2021 Eugene Fox

Licensed under MIT License