Whoever knew the password could guess codes at 10 an hour forever,
unnoticed, each guess checked against every authenticator (the second
reading's M4). Every code an account's second factor refuses after a
right password (sign-in, a phrase's reset, a change) or from a signed-in
device (removing an authenticator, new recovery codes, the code from one
confirmed before) now counts, per account, from every network; after
every tenth in a row no code is taken (codesWait, saying until when), an
hour, then twice as long each time, a day at the most (longestCodeWait,
second_factor_waits.dart): at a day, ten guesses a day still have about a
1 % chance a year against one authenticator, so the first wait mails the
owner that someone knows their password. The instance keeps no address,
so sign-in and the phrase's reset now send the address the device typed
(and its language), used only for that mail after its hash is checked
against the account's. A code accepted clears it all.
Migration (module, Learn's and Todo's servers, Learn's device schema):
CREATE TABLE "second_factor_failures" ("id" bigserial PRIMARY KEY,
"authUserId" uuid NOT NULL, "failures" bigint NOT NULL, "waits"
bigint NOT NULL, "waitUntil" timestamp, "updatedAt" timestamp NOT
NULL) with a unique index on "authUserId": a new table, nothing
touched.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
Three of the second reading's lows:
- A member waits at most 5 seconds (maxClockSkew) for the register's
moment before making a session after a reset; a clock further behind
is refused at once (unavailable, logged), rather than holding the
request for as long as the clocks differ.
- instanceSecret, which lets a service set passwords and delete accounts
for anyone, stops the server when set shorter than 32 characters, as
the password keys do.
- A change of password, a reset keeping the keys and a new phrase each
write their own columns alone (writeNewPassword, columns: in
setRecoveryKeys), so one made from the row as it was before another
never undoes it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
Nothing tied a sign-in's proof to the instance it was made for: an
instance a person was lured into adding could pass A, M1 and the code on
to the real register and get a session there, and pass a phrase's proof
on with a password of its own in place of the person's (the second
reading's M6). SRP's identity is now a label, the challenge's ID and
the host the device addressed (passwordIdentity, in halkyon_base_client
and halkyon_base_server alike), and the phrase's proof signs that host,
what it is for (an authenticator's reset or a new password) and the new
password's digest (key proof v2). Every proving call carries the host;
in production it must be the server's apiServer.publicHost (otherwise
otherInstance, which the app shows as an instance it can't trust), in
development any; a member forwards its own. The tests prove that a
relayed sign-in, a proof for another host or purpose, and a swapped
password are refused, nothing changing.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
A key proof was a signature by the account's signing key, which every
signed-in device keeps in its keyring: whoever could read one, with a
code from its authenticator, set a new password without the password or
the phrase (the second reading's H1). The phrase now proves itself with
an Ed25519 key derived from its bits alone (halkyon_keys'
recoveryProofKeysOf, KDF context hlkrprf1, a sibling of the recovery
key), whose public half every setup, new phrase and account reset sends
and the register keeps (account_password.recoveryProofKey); the device
derives the secret half only while the phrase is typed. An account
without one (none exist outside development) proves no phrase until it
sets a new one; decoys check against a decoy proof key alike.
Migration (module, Learn's and Todo's servers, Learn's device schema):
ALTER TABLE "account_password" ADD COLUMN "recoveryProofKey" bytea;
nullable, so rows made before keep working and no data is touched.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
password.setRecoveryKeys took a session and a TOTP code alone, so a phone
signed in with its authenticator beside it could set a phrase of its
holder's own and, through the phrase's reset, a new password, never
knowing the old one. It now takes the old password's SRP proof (from
beginChange, the caller's own) and a TOTP or recovery code, as changing
the password does: one owner proof for both (_proveOwner), forwarded by
members, asked for in the account section's New recovery phrase.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
ADR 0017, step 3 (D4: nobody signs in with email codes yet, so the
password replaces them outright). `emailCode.verifyCode`,
`emailSignIn.signIn` and the switch token go, with the register's
`verifySignInCode` and `completeEmailSwitch` and their operations
between services. `emailCode.sendCode` stays, now without a session
(signing up and getting back in have none), as what proves an address
for a password's setup, a sign-up, a setup never finished and the
resets; `accountRecovery.sendCode`, which did that for the resets,
goes. The `switchChallengeId` column stays: Serverpod's challenges
still link a completion token, and older servers read it during a
deploy.
The apps: halkyon_app's email sign-in (its bloc, sheet, gateway calls
and the start screen's Continue with email) goes; Learn's profile and
Todo's account sheet show `AccountSecuritySection` (a password set up
by someone anonymous or signing in with GitHub, whose end it names;
the authenticators; changing the password; new recovery codes and
phrase), which reads anew after every change the repository makes.
BREAKING CHANGE: Learn's `minimumAppBuild` is 22: builds up to 21 sign
in with the endpoints that went. Todo was never released and stays at
build 1.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
ADR 0017, step 3. `password.beginChange` and `password.change` take the
old password's SRP proof and a TOTP or recovery code, and the same keys
wrapped under the new password; a session alone changes nothing, and an
account without a confirmed authenticator is told to set one up first.
`password.setRecoveryKeys` replaces the keys' wrapping under the
recovery phrase for a TOTP code, so a device holding the keys can make
a new phrase.
A change of password ends every other session of the account in every
service of the instance; resets of the password and of the account end
them all. The register ends its own and keeps a notice per member
(`sessions_ended_notice`, a migration that only creates it), told at
once and hourly until it confirms, as deletions are told: it names a
moment, so sessions made since stay, and the session that asked for a
change. A member answering one ends its sessions made before that
moment; a member signing someone in after a reset ends its own first
and makes the new session only once its clock is past the moment.
A reset not due says when it takes effect (`takesEffectAt` on
`PasswordRefusedException`), across members too.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
ADR 0017, step 3. Signing up takes an address a mailed code proves and
a password's setup, without a session (`passwordSignIn.signUp`): an
address nobody has becomes a new identified account, and an account
with the address but no password (codes by mail before; no keys exist,
so nothing waits) takes the password, keeping its ID. A setup never
finished signs in with its password and a code mailed to the address it
began with, until an authenticator is confirmed, which also calls off a
reset of the account waiting; any other account takes no code by mail
in place of its second factor and leaves the code unused. A reset of
the whole account waiting no longer counts as having had an
authenticator, so its owner isn't locked out until it completes.
Members forward both through the register; the tests' shared helpers
move into `support/password_support.dart`.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
`password.set` replaced a password whenever the account had no confirmed
authenticator, which is also the state an authenticator's or the
account's reset leaves behind; and in that state a code by mail or GitHub
signed in again. So whoever got a session another way could replace the
password and the keys, skipping the reset's 72 hours.
An account had a confirmed authenticator while it has one or a reset of it
stands (`hadConfirmedAuthenticator`: the reset's row stays until a new
authenticator is confirmed). Then `password.set` is refused
(`passwordExists`), and the account signs in with its password alone:
codes by mail and GitHub are refused (`usePassword`), the latter through
`SignInWays.passwordOnly`, which members read from the register.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
Enrolling and confirming an authenticator took only a session, so whoever
held one (a stolen token) could add a second factor of their own, then use
its codes to remove the owner's and make new recovery codes.
While the account has a confirmed authenticator, confirming another now
also takes a code from one of those (`existingCode`, each step's code once
as signing in takes it, within the same 10 tries an hour), refused as
`wrongExistingCode`; it is checked only once the new one's code is right,
so a wrong one uses none. The first authenticator, and the first after a
reset carried out, need none. Members forward it to the register.
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>
halkyon_base runs as the instance's register or as one of its members.
The register keeps the ways in, handles and profiles; members ask it
over HTTP with the instance's shared secret (instanceSecret), and open
sessions of their own for its accounts, under the same account ID.
- AccountsMode from the environment: INSTANCE_MEMBERS on the register,
ACCOUNT_REGISTER_URL on a member. Learn always holds the register
(Explore joins the profiles); Todo is a member where it is set.
- AccountRegister: LocalRegister, RemoteRegister, an in-memory one in
tests. Calls between services on the web server, refused without the
secret (constant-time compare); a server needing it doesn't start
without it.
- Deleting an account deletes it everywhere: notices per member kept in
the deletion's transaction (account_deletion_notice), told at once and
hourly until confirmed; members prune daily whom the register no longer
knows, never while it knows none of them or can't be reached.
- Deploy: INSTANCE_SECRET and INSTANCE_MEMBERS in compose and .env.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>
