Features / Sign in with your phone

TestingProved in Lean 4

Passwords that open only on your phone.

Every saved password is encrypted with a key only your phone can produce, for that one entry, after the phone checks it is you. The PC never holds the key at rest, so a stolen PC or a copied disk gives up no password.

0

passwords on a stolen PC or a copied disk

1 page

the password goes to the page that asked, and nowhere else

Limited

prompts in any time window, so a program cannot wear you down

How it works

Ask, approve, fill

1

Ask

A sign-in page over verified HTTPS asks. The ZENOS browser shows a two-digit code.

  • Pages with a distrusted certificate never get here
2

Approve

Your phone shows the site, the account and three codes. You tap the one on your PC, then use fingerprint or face.

  • The phone's passkey signs this request only
3

Fill

The entry's key travels encrypted to a one-time key, and the password is filled into the same tab and page.

  • Every request is answered at most once

Proven, and what is not

Release is mathematics

Proved in Lean 4

Checked on every build

  • A password is released only to the page it was saved for, over verified TLS, in time, after the registered phone signed this very request with the person verified
  • Every request is answered at most once; an answer cannot be replayed, and a wrong code cannot be retried
  • However many requests a program sends, only a fixed number of prompts reach the phone in any window
Trusted, not proved

Tested and listed openly

  • The passkey signature, the phone's PRF, ECDH and HKDF
  • Tested with software and virtual passkeys, not yet on a physical phone
  • A PC already taken over while you approve

Try it in the preview

Try it yourself

1

Register your phone

The administrator gives a one-time enrolment code; you register in ZENOS Messages.

2

Save a password

Sign in to a site in the ZENOS browser and save it.

3

Sign in again

Approve on your phone with the matching code. The page is filled.