ADR 0017, step 3: halkyon_app's side, which Learn and Todo take.
- The account's cryptography on the device (`SodiumAccountCrypto`):
halkyon_keys and SRP's client half, each step on an isolate of its
own. sodium hands out results as views of native memory its
finalizers free once the isolate that made them ends, so everything
crossing back is copied first: a view read freed memory and crashed
the process.
- `PasswordGateway` on the module's endpoints (steps without a session
through a client holding none; an authenticator set up with a session
granted but not yet the device's), and `PasswordRepository` running
the flows: signing in (M2 checked, the keys opened before anything is
trusted), signing up, a password for someone signed in, an account
never finished, the authenticators, recovery codes, changing the
password, a new recovery phrase, and getting back in.
- The unlocked keys in the system's keyring per instance and person
(`SecureAccountKeyStore`), gone once another person signs in or
nobody, and with the instance's removal.
- The screens: the start screen's Sign in and Create an account (and
when GitHub sign-in ends), the sign-in sheet (codes, recovery codes,
an account never finished, a lost authenticator), the account's setup
(the recovery phrase shown once, three random words typed back before
anything reaches the instance; the authenticator's QR code, drawn
with pub.dev's qr; the recovery codes), getting back in, and the
account section (`AccountSecuritySection`).
- `FileSaver` moves from Learn into halkyon_app, for the phrase and the
codes in Todo too; `AppDependencies` names it and `passwords`.
- halkyon_keys rebuilds account keys from the secret keys a device kept;
the key proof's message is in halkyon_base_client, checked against
the register's.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
The register's side of signing in with an address, a password that never
leaves the device (SRP-6a) and a code from an authenticator (ADR 0017),
with members forwarding every step through AccountRegister:
- password.set: salt, Argon2id's costs, SRP's verifier, the public keys
and the private keys wrapped twice, all made on the device; with the
address a mailed code proves, an anonymous person becomes identified
under their ID. It signs in once an authenticator is confirmed.
- passwordSignIn.begin and complete: SRP's two steps with a TOTP or
recovery code. An address nobody has is answered from a decoy key as
an account would be; every wrong credential is refused alike.
- authenticator: secrets sealed under totpKey (XChaCha20-Poly1305, bound
to their row), each code accepted once, ten recovery codes with the
first, the last one kept.
- accountRecovery: a lost authenticator reset 72 hours after the
password and a mailed code or the recovery phrase ask, a lost password
set anew with the phrase's signature, or the account reset with new
keys 72 hours after a mailed code asks; a mail at each start, a
sign-in calling it off.
- An account with a password no longer signs in by a mailed code or
GitHub; no new GitHub account is linked where passwords are offered,
and from GITHUB_SIGN_IN_ENDS GitHub signs nobody in and its IDs go.
Five tables, added by the module's migration; deletePerson deletes
their rows.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
