# Using two-factor authentication within coded automations

> This tutorial shows how to include sample code that generates two-factor authentication codes for your automations. Here are the ways to implement the two-factor authentication code:

This tutorial shows how to include sample code that generates two-factor authentication codes for your automations. Here are the ways to implement the two-factor authentication code:

* Copy and paste the code into a CS file of your target project.
* Use a sample NUPKG file in your project. When opting to use the sample NUPKG file, you have the capability to add the two-factor authentication as an activity within your XAML files.

  :::tip
  Regardless of whether you choose to integrate the sample two-factor authentication code generator in your CS files (for coded automations) or XAML files (for low-code automations), remember that you can invoke a coded automation into a low-code one and vice versa. For more information about hybrid automations, visit [Creating hybrid automations - Combining Coded and Low-code Workflows](https://docs.uipath.com/studio/standalone/2024.10/user-guide/creating-hybrid-automations).
  :::

  ## Copy and paste the code in CS files

To use the two-factor authentication sample in your coded automation, you can copy and paste the following sample code in a CS file from your target project.
:::note
The sample code generates a new authentication code every 30 seconds. For example, if an authentication code is generated at 3 hours, 45 minutes, and 27 seconds, that code is available for three seconds. A new code is then generated at the 30 seconds mark.
:::

```
using System;
using System.Collections.Generic;
using UiPath.CodedWorkflows;
using System.Security.Cryptography;

namespace GenerateTwoFactorAuthenticationCode
{
    public class Workflow : CodedWorkflow
    {
        [Workflow]
        public string Execute(string secretKey)
        {
            return AuthenticationCode(secretKey);
        }

        private string AuthenticationCode(string secret)
        {
            // Step 1: Decode the base32 secret key
            byte[] key = Base32Decode(secret);

            // Step 2: Calculate the time step (current time divided by 30 seconds)
            long unixTime = DateTimeOffset.UtcNow.ToUnixTimeSeconds();
            long timeStep = unixTime / 30;

            // Step 3: Convert time step to byte array (8 bytes, big-endian)
            byte[] timeBytes = BitConverter.GetBytes(timeStep);
            if (BitConverter.IsLittleEndian)
                Array.Reverse(timeBytes);

            // Step 4: Generate HMAC-SHA1 hash using the time step as message and secret key
            using (HMACSHA1 hmac = new HMACSHA1(key))
            {
                byte[] hash = hmac.ComputeHash(timeBytes);

                // Step 5: Extract dynamic binary code (4 bytes) from the hash
                int offset = hash[hash.Length - 1] & 0x0F;
                int binaryCode = (hash[offset] & 0x7F) << 24
                               | (hash[offset + 1] & 0xFF) << 16
                               | (hash[offset + 2] & 0xFF) << 8
                               | (hash[offset + 3] & 0xFF);

                // Step 6: Modulo to get a 6-digit code
                int otp = binaryCode % 1_000_000;

                // Return the OTP as a zero-padded 6-digit string
                return otp.ToString("D6");
            }
        }

        // Base32 decoding function to get the byte array from the base32-encoded key
        private static byte[] Base32Decode(string base32)
        {
            // Decode Base32-encoded string to byte array
            const string base32Chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567";
            int bitBuffer = 0;
            int bitBufferLen = 0;
            var result = new List<byte>();

            foreach (char c in base32.ToUpper())
            {
                if (c == '=') break;

                int index = base32Chars.IndexOf(c);
                if (index < 0) throw new ArgumentException("Invalid Base32 character");

                bitBuffer = (bitBuffer << 5) | index;
                bitBufferLen += 5;

                if (bitBufferLen >= 8)
                {
                    result.Add((byte)(bitBuffer >> (bitBufferLen - 8)));
                    bitBufferLen -= 8;
                }
            }

            return result.ToArray();
        }
    }
}
```

## Use a sample NUPKG file

If you want to use a sample NUPKG file for including the two-factor code in your automations, follow these steps:

1. Download the following NUPKG file: [GenerateTwoFactorAuthenticationCode.nupkg](https://github.com/UiPath/codedautomations-samples/tree/main/GenerateTwoFactorAuthenticationCode).
2. Upload the downloaded NUPKG file to your **Orchestrator Host** or **Tenant** feed, which are accessible through your Studio instance. For more information on uploading the NUPKG file as a custom library to Orchestrator, visit [Manually uploading a library to Orchestrator](https://docs.uipath.com/orchestrator/automation-cloud/latest/user-guide/managing-libraries#manually-uploading-a-library-to-orchestrator).
3. Open your Studio project and open the **Manage Packages** menu.
4. Search for the `GenerateTwoFactorAuthenticationCode` NUPKG file you previously saved to your **Orchestrator Host** or **Orchestrator Tenant** feed, and install it.

Figure 1. The custom library in the Manage Packages menu

   ![The custom library in the Manage Packages menu](https://dev-assets.cms.uipath.com/assets/images/studio/2024-10-the-custom-library-in-the-manage-packages-menu-510405-0d58f969.webp)

After you install the file, navigate to the **Activities** panel and locate **GenerateTwoFactorAuthenticationCode**. Drag and drop the **Get 2FA token** activity into your XAML files to generate an authentication code for your automations.

Figure 2. The **GenerateTwoFactorAuthentication** code sample in the **Activities** panel

   ![The GenerateTwoFactorAuthentication code sample in the Activities panel](https://dev-assets.cms.uipath.com/assets/images/studio/2024-10-the-generatetwofactorauthentication-code-sample-in-the-activities-panel-509862-680f3cf5.webp)