Commit Graph
2 Commits
Author SHA1 Message Date
jaap-jan 7a3a521c59 Give the phone the rest of its screens, and a way in
ci / build and test (push) Failing after 2s
ci / android head (push) Failing after 1s
All seven screens of the design, plus the two it does not draw because it starts at an
enrolled phone: naming a server, and choosing a passphrase.

The five states docs/android-port.md worried about losing at 360dp are all here and none
of them softened. The changed-key refusal is a full-screen panel rather than a bottom
sheet, because a sheet is swipe-to-dismiss by convention and that screen must have no way
forward. The recovery code raises FLAG_SECURE for its own state and lowers it afterwards,
so the sentence about screenshots is true rather than decorative. The delete
confirmations keep their counts and replace the row in place.

Signing in works, and the seam it needed is worth more than the implementation:
IAuthorizationCallback now sits between OidcClient and the loopback listener, so the two
heads differ in where the response arrives and in nothing else. PKCE, the state check,
discovery, the token exchange and the key binding stay one implementation — a second OIDC
client would be a second place for a security bug to live. The phone registers a
private-use scheme with the system rather than binding a loopback port, which on a shared
device any other app can do first.

The accessory key row needed TerminalWorkspace.SendInputAsync: ordinary typing goes from
the renderer straight down the socket, and there was no way in for the keys a software
keyboard does not have. Ctrl latches, because one thumb cannot chord, and the latch is
drawn — a modifier that is on and does not look on is how somebody sends ^L to a database
prompt believing they typed an l.

597 client tests green, including two new ones for the input path and one for the
terminal surface command. Nothing has run on a device.
2026-07-31 21:43:11 +02:00
jaap-jan 94f66be5e8 Add the OIDC client: PKCE loopback sign-in and the key binding flow
Authorization Code with PKCE on a loopback redirect, per RFC 6749, RFC 7636
and RFC 8252. Zero package references: the flow is fully specified, and the
one thing a library would own for us -- nonce generation and validation -- is
exactly what the key binding needs to control. Duende's OidcClient generates
and validates its own nonce as an internal detail, and the binding requires
the nonce be a specific value: the hash of the key statement being enrolled.
Fighting that is worse than owning the flow.

AuthorizeKeyBindingAsync is the client half of the primary trust anchor. It
runs a second authorization with nonce set to the statement hash and
prompt=login, so the ID token that returns is the provider's signature over
exactly those public keys, attesting to a user present now rather than to a
session opened at some unknown earlier time. It requests only openid -- a
second refresh token would be one more long-lived credential for no benefit
-- and rejects a token whose nonce is not the one it asked for, because
enrolling that would store evidence verifying against keys we are not
publishing.

The nonce is read without validating the ID token's signature. Sanctioned by
OIDC Core 3.1.3.7: for a token received by direct communication with the
token endpoint, TLS server authentication may stand in for signature
checking. That reasoning does not extend to another user's binding, which
arrives via the DodoSSH server and must be verified against JWKS fetched
directly -- the directory work in M3.

Raw TcpListener rather than HttpListener for the redirect: an ephemeral port
can be bound and read atomically instead of picking one and hoping it is
still free, there is no HTTP.SYS URL-ACL question on Windows, and the whole
surface is one request line. It answers 404 on other paths and keeps
waiting, because a browser asks for /favicon.ico first and treating that as
the callback would abort every sign-in. 127.0.0.1 rather than localhost: RFC
8252 permits either, but the name resolves through the hosts file.

20 tests, driving the real listener over TCP with a fake browser that
actually fetches the redirect -- injecting a fabricated callback would skip
the parsing, path filtering and response writing that can break. Mostly
negative, because the loopback port is reachable by every local process: a
response with the wrong state is rejected *and* never reaches the token
endpoint, metadata declaring an issuer other than its own authority is
rejected (RFC 8414 3.3, without which a mix-up attack works), a provider
offering only 'plain' is fatal rather than a silent downgrade, and the
verifier sent is checked against the challenge advertised so PKCE is not
theatre that only fails in production.

Two bugs caught by writing the tests: the authorize URL builder dropped
client_id entirely after a refactor, and CancellationTokenSource.CancelAfter
has no TimeProvider overload -- so the browser timeout is now constructed
with the clock and a test can advance it instead of waiting five minutes.
2026-07-28 21:13:35 +02:00