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Access-First Authentication with QR + Device Signatures

Toqen.app is now live on the App Store.

This is an attempt to rethink authentication from an access-first perspective: instead of managing identities and credentials, focus on granting access in real time, per request.


Why rethink authentication

Most systems still rely on reusable credentials:

  • passwords
  • session tokens
  • API keys

These introduce predictable problems:

  • credential leaks
  • replay attacks
  • uncontrolled sharing

Even with MFA, the core model remains static.


Core idea

Each access request should be:

  • short-lived
  • single-use
  • bound to a device
  • cryptographically verifiable

Instead of storing secrets, the system verifies a signed challenge.


Flow

User opens login page
↓
Server generates request
↓
QR code is displayed
↓
Mobile app scans QR
↓
User confirms access
↓
Device signs challenge
↓
Server verifies signature
↓
Access granted


QR format

QR does not contain secrets.

Example:

toqen://auth?request_id=91f2d&challenge=8fa92c1a&expires=1710000000

Properties:

  • expires in 30–60 seconds
  • single-use
  • cannot be replayed

Device model

On first launch:

  • device generates key pair
  • private key → stored in secure storage
  • public key → registered on server

Signing:

signature = sign(challenge, device_private_key)

Verification:

verify(signature, device_public_key)


Security properties

  • no reusable credentials
  • no secrets in QR
  • replay protection via TTL + single-use
  • device-bound authorization
  • server stores only public keys

Vault model

Sensitive data is encrypted client-side:

  • encrypted_vault
  • AES-256-GCM
  • vault_key stored in secure storage

Server never has decryption capability.


Where this fits

  • admin access
  • internal tools
  • high-risk operations
  • temporary access flows

Current status

  • iOS app is live on the App Store
  • Android version is in testing

Open for feedback

If you are working on authentication, security, or access control systems — feedback is welcome.

Contact: https://www.toqen.app/about#contacts

Android early access: https://forms.gle/f9FcbHyHJiajmFWV7


Building continues.

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