Create and recover signers

Create and manage embedded wallets for your users

Understanding embedded signers#

To create wallets for your users during the login flow, you need to configure the embedded signer. The configuration depends on your chosen recovery method, so it's important to decide on your recovery strategy first.

Make sure to wait for the embedded state ready before using the embedded signer. Learn more about how to check the embedded state.

Decide a recovery method#

Recovering the embedded signer is needed when a user logs into a new device or when the embedded signer is lost.

Openfort embedded signers have two core recovery modes: automatic recovery and user-based recovery. At a high-level, this setting modulates how the embedded signer's recovery share is encrypted and stored.

Automatic recovery: The recovery share is encrypted with a combination of project entropy and Openfort's entropy. When logging into a new device, users can immediately access their embedded signer.

Shield configuration

Before configuring the automatic recovery, generate your project's publishable and secret shield keys and store the encryption share. Learn about the differrent API keys here.

User-based recovery: The recovery share is encrypted by user-provided entropy. When logging into a new device, users must enter in their password to recover the embedded signer on the new device. Once the embedded signer has been recovered on a device, users will not need to enter their password on that devices again.

Automatic recovery#

It is worth noting that while automatic recovery makes for smooth user UX (without needing to set up a recovery system upfront when logging in), it comes with tradeoffs. Notably, the root of trust with is in the user’s authentication token. This means access to the auth token grants access to the wallet. Accordingly, this token must be properly secured at all times.

When using automatic recovery, Shield generates a password that is used for the encryption of the recovery share. The full encryption key can only be accessed if the decryption request includes the user's auth token.

Encryption share

When using automatic recovery, its very important to ensure that the encryption share should not be available from the client side of the application.

From your backend, you should have an endpoint that generates an encryption session for the user. This endpoint should be protected and only accessible by the user who is requesting the encryption session (i.e. the user who is logging in).

An encryption session is requested every time configureEmbeddedSigner is called. The encryption session is only valid for a single use.

For example, in a Next.js API route, you can create an endpoint like this:

protected-create-encryption-session.ts

openfortAdminConfig.ts

import openfort from './openfortAdminConfig';
export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
    const session = await openfort.registerRecoverySession('YOUR_SHIELD_PUBLISHABLE_KEY', 'YOUR_SHIELD_SECRET_KEY', 'YOUR_SHIELD_ENCRYPTION_SHARE')
    res.status(200).send({
        session: session,
    });
}

Once we've secured the backend we setup the client side:

openfortManager.cs

encryptionSession.cs

using System;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.Networking;
using Openfort.OpenfortSDK;
using Openfort.OpenfortSDK.Model;
using static Clients.Shield;
public class EmbeddedSignerManager : MonoBehaviour 
{
    private OpenfortSDK openfort;
    // Setup with Openfort authentication
    public async Task SetupAutomaticRecoveryWithOpenfort(string email, string password)
    {
        try 
        {
            // Sign up the user
            AuthResponse response = await openfort.SignUpWithEmailPassword(email, password);
            string token = response.Token;
            
            // Get encryption session from your backend
            string encryptionSession = await GetEncryptionSession();
            
            // Configure the signer
            int chainId = 80002; // Polygon Amoy testnet
            ShieldAuthentication shieldConfig = new ShieldAuthentication(
                ShieldAuthType.Openfort, 
                token
            )
            {
                EncryptionSession = encryptionSession
            };
            EmbeddedSignerRequest request = new EmbeddedSignerRequest(chainId, shieldConfig);
            await openfort.ConfigureEmbeddedSigner(request);
            
            Debug.Log("Automatic recovery setup complete");
        }
        catch (Exception e)
        {
            Debug.LogError($"Error setting up automatic recovery: {e.Message}");
        }
    }
}

We recommend enabling user-based recovery for users. This is especially important to enforce as the value of assets in a user's wallet grows.

User-based recovery#

Password recovery

Require that users set a password when the wallet is created, enforcing password-based recovery from the start.

If encrypted by user-provided entropy, only the user can decrypt the recovery share. Openfort never sees or the user's password. Therefore, if you're not planning to ever user the automatic recovery mode, you can use the encryption share in the client side of the application.

using Openfort.OpenfortSDK;
using Openfort.OpenfortSDK.Model;
public class openfortManager: MonoBehaviour 
{
    private OpenfortSDK Openfort;
    private async void AuthAndSetPassordRecoveryMethod(string email, string password, string recoveryPassword)
    {
        AuthResponse response = await Openfort.SignUpWithEmailPassword(email, password);
        string token = response.Token;
        int chainId = 80002;
        ShieldAuthentication shieldConfig = new ShieldAuthentication(ShieldAuthType.Openfort, token);
        EmbeddedSignerRequest request = new EmbeddedSignerRequest(chainId, shieldConfig, recoveryPassword);
        await Openfort.ConfigureEmbeddedSigner(request);
    }
}

Pregeneration#

Openfort also allows you to pregenerate embedded wallets for your users, even before they first login to your game. Please see our pregeneration guide for more.