2 Commits

Include renames

Author	SHA1	Message	Date
jaap-jan	f86791e817	Finish revoking a device, instead of half of it ... ForgetDeviceAsync stopped this machine unlocking without a passphrase and left the server's row exactly where it was, so the account went on listing a device nobody could account for. ADR 0007 recorded that as a deliberate gap needing an endpoint. This is the endpoint, and the two things that turned up behind it. DELETE /api/v1/me/devices/{id}. The device row is not the dangerous half: a kind=device wrap is the user's identity bundle sealed to a key somebody may be holding, and that is what has to go. It goes on the foreign key's cascade rather than a second statement, and RevokeDevice_TakesItsWrapWithIt asserts the cascade rather than trusting the configuration to keep saying so. Scoped to the caller's own account, which is the only authorisation check there is. The id is an unguessable v7 GUID, but unguessable is not a permission — without the scope one user could withdraw another's device key by pasting an id they saw once, and the victim's next launch would ask for a passphrase with no explanation. 404 rather than 403 for somebody else's device, so a stranger does not learn the id exists. Never refused for being the last device. ADR 0001 makes an enrolled device a recovery path, so removing the last one does cost the user something — but the machine being revoked is most likely the one they have just lost, and a server that argued about it would be refusing the one request that has to work immediately. The passphrase wrap is untouched either way, which RevokeDevice_LeavesThePassphraseWrapAlone pins. --- Two things found on the way --- Registering twice from one machine left two devices on the account. The server is idempotent on the public key, but the client generates a fresh key pair every call and the keystore holds one — so the second registration orphaned a wrap whose private half had just been overwritten, which is precisely the leftover this change exists to remove. Registering now withdraws the previous device. Found by a test that asserted the property and failed. And the fakes were lying about it. FakeAccountServer's comment claimed the real service's idempotence while handing back a fresh Guid on every call, which is invisible until something revokes by id — at which point a test would be revoking an id the server never issued, and passing. Both fakes now issue one id per public key and drop the wrap with the device, as the cascade does. --- Reachable at all --- ForgetDeviceAsync had exactly one caller and it was a test, so "Stop unlocking here" now sits in the account bar where "Use Windows Hello here" was. Its own flag rather than the negation of that one: a machine with no TPM and a machine that is already registered are both "cannot register", and only the second has anything to take back. No confirmation prompt, deliberately. The cost of pressing it by accident is one passphrase and one re-registration; the cost of a dialog is a moment's hesitation at the point somebody has realised a machine is in the wrong hands. Offline it does the local half and says so rather than refusing. Whether this machine may unlock itself is decided entirely by the local cache and the local keystore — the unlock path never asks the server — so forgetting here is what actually revokes, and "you are offline, so this machine will go on unlocking itself" would be the worst available answer. DeviceRevocation.LocalOnly is what the interface reports and the status line explains what is left to do. The local half runs first for the same reason, and the keystore call is the first thing in the method that can yield: on Windows it raises a consent dialog, and a dialog wants the thread it was called from. That ordering is currently load-bearing and shakier than it looks — see the open device-unlock hang. Four mutations, all caught: dropping the user scope from the server query (1 test), skipping the stale-device revoke on re-registration (2), skipping the server call in ForgetDeviceAsync (2), and the earlier version of the client that never called it at all. 930 tests green across 16 projects, 13 of them new. Zero warnings, format clean.	2026-07-30 17:33:31 +02:00
jaap-jan	1faea42b94	Unlock with this machine's device key, without a passphrase or a network ... The second of ADR 0007's three pieces: the seam a keystore plugs into, the wrap cached where an offline unlock can reach it, and the unlock path itself. What is still missing is the keystore — UnavailableDeviceKeyStore is what the application composes for now, so behaviour is unchanged until piece three lands. IDeviceKeyStore holds exactly 32 bytes, and only because the cache key moved first. It would have had to hold the local cache key alongside the X25519 scalar — a second live secret at rest, going stale on every passphrase change — had 7016ce3 not re-keyed that to the identity bundle. ADeviceUnlock_ReadsTheSameCache ThePassphraseWrote is the test that ties the two commits together: under the old derivation this session would have opened the identity and then found its own cache unreadable. The wrap is cached at registration rather than fetched at unlock, which is the whole point. The one unlock path that exists to save the user typing must not be the one that only works online; a laptop on a plane is precisely where a gesture should help. Every way this fails returns a status rather than throwing, because none of them are exceptional — a cancelled fingerprint prompt is the most ordinary thing in this file. Three statuses rather than one, because the caller says a different sentence for each: no device registered (the normal state of a machine nobody opted in on), the machine would not release the key (declined gesture, or a Hello key invalidated by a PIN reset — deliberately indistinguishable, since the remedy does not differ), and the key was released and did not open the wrap (a rotated identity, which will never succeed again and needs re-registering). A keystore returning the wrong number of bytes lands in the third rather than crashing the unlock screen. The subtle defect this could have shipped is in UnlockStore.Apply. That method runs on every sign-in from a /me response, which knows nothing about this machine's keystore — so assigning the device columns unconditionally would delete the wrap on the next launch, and the user's fingerprint would stop working for no visible reason and no error anywhere. The columns are therefore written only when the incoming material carries them, with AttachDeviceAsync and DetachDeviceAsync as the only paths that set them deliberately. Mutation tested: removing the guard fails RefreshingTheProfile_DoesNotDiscardTheDeviceWrap and nothing else. RegisterDeviceAsync lives on VaultSession because sealing the bundle is the one step only an open session can do, and the session is the bundle's custodian. Everything else arrives as a parameter, exactly as SyncAsync takes its transport, so the session still knows nothing about how either the wire or the keystore is implemented. Its steps are ordered so a failure cannot leave a lie behind: the key is generated, saved locally, and only then registered with the server. A server row whose private half was never stored is a device that can never unlock and that the account claims can — worse than not offering the feature at all — so the write that could produce it happens after the one that prevents it. ForgetDeviceAsync is deliberately half a job, and says so. It stops this machine unlocking without a passphrase, which is what a user turning the feature off means, but the server's wrap row survives and the account will go on listing a device that cannot unlock. Deleting it needs an endpoint that does not exist yet. Half with the gap recorded beats a method whose name promises the other half. The client cache gained two nullable columns and a migration, generated rather than hand-written this time. 876 tests green, 10 of them new. Zero warnings, dotnet format clean. Remaining: the Windows Hello store and the unlock-screen UI. That is where the Windows target framework lands, and where automated testing stops — a gesture needs hardware and a person, so the last piece is the one that has to be looked at rather than asserted.	2026-07-30 13:37:35 +02:00