Commit Graph
2 Commits
Author SHA1 Message Date
jaap-jan 575a9a9f5e Stop the relay checkbox promising a connection this client cannot make
ci / build and test (push) Successful in 2m7s
ci / android head (push) Successful in 3m15s
ci / desktop nightly (push) Successful in 47s
ci / api image (push) Successful in 25s
Ticking "Connect through the server relay" moved the host's address and port out of the encrypted payload
into plaintext columns on the server — the single deliberate privacy concession in the design, per ADR 0004
— and then the client dialled the address directly, exactly as it does with the box clear. VaultViewModel
builds SshConnectionRequest(hostname, port, username, credential) and nothing on this side reads
RelayEnabled at all. The connection failed the way it always had, for a machine the laptop could not reach,
with nothing saying the box had done nothing.

The server half is built and shipped: tickets, the WebSocket, the deny list, the CHECK constraint that
enforces a non-null address for a relay-enabled host. What does not exist is the client's path to it, so
this is an unfinished feature rather than a broken one — but the control in front of it was collecting the
cost of the finished version.

Both heads now say so, in the label and in the first sentence of the paragraph under it. Not disabled, and
that is the one decision here worth stating: a host somebody has already ticked has to be able to lose the
flag, and a control greyed out with the concession switched on would trap it there. Tickable and honest
beats untickable and stuck.

This is step 0 of docs/reaching-a-host-you-cannot-dial.md, and the only step of it that should ship alone —
the sentence is written to be deleted when the bridge lands.

VERIFIED. Build clean, 112 layout tests. The drawer's paragraph is longer than it was and the host editor is
measured with the drawer open at the window's minimum, so the wrap is held inside the column rather than
assumed to fit.
2026-08-07 08:47:02 +02:00
jaap-jan 6185d74800 Write down the two things a user is promised and does not get
Two plans, both for the same class of defect: a control or a code that a user is told to rely on, backed by
storage and by nothing else. Neither is started; what follows is the reasoning, so that starting is not
where it gets thought about.

── UNLOCKING WITHOUT THE PASSPHRASE ─────────────────────────────────────────────────────────────────────
Every account is issued a recovery code at enrollment. The client generates it, wraps the identity bundle
under KEK_rc, the server stores that wrap as UserKeyWrapKind.Recovery, and both heads work to make sure the
user writes it down — the phone raises FLAG_SECURE for that screen alone and will not let anybody past it.
Nothing can use it. SessionOpener has UnlockAsync and UnlockWithDeviceAsync, and there is no third.

Walk the failure through: forget the passphrase, and the bundle cannot be unwrapped, so no vault key opens
and every item is unreadable. Signing out and back in returns the same passphrase wrap. The device key
would be the other door, and sign-out withdraws it — which is the advice the unlock screen gives for
exactly this situation. The loss is total and permanent, and the thing built to prevent it is inert.

The docs already disagree with each other about this, which is how it surfaced. manual-checks §10.2 calls
the code "the only thing standing between a forgotten passphrase and an unrecoverable vault"; android-port
says losing it *along with* the passphrase is what makes a vault unrecoverable; README says signing out is
the only answer and nothing can recover one. The third is the true one today.

More than half the work is already done and one piece of it was done on purpose: LocalCacheKey derives from
the identity bundle rather than from MK — crypto.md §3.2, changed 2026-07-30 — specifically so an unlock
that never computes MK can still read the cache it wrote. What is missing is an endpoint to serve the wrap,
an unlock path, and a way to set a new passphrase afterwards, without which the account unlocks with a
one-time code forever. That last step is the same re-wrap a change-passphrase feature needs, so it delivers
both.

Two traps are recorded because both would produce a code that verifies nowhere. The derivation uses the
displayed string *including its dashes*, so the unlock must canonicalise to the printed form rather than
strip it; and the recovery wrap uses a different Argon2 profile to the passphrase one (64 MiB against 256),
so it must derive from the parameters served with the wrap rather than from a profile constant.

── REACHING A HOST YOU CANNOT DIAL ──────────────────────────────────────────────────────────────────────
This started as "delete the dead jump-host field" and inverted twice.

HostSecret.JumpHostIds is stored, validated, encoded and three-way merged, and nothing reads it or writes
it — the ssh_config importer looks like the writer and is not; it records ProxyJump as an option and a note
saying DodoSSH cannot honour it. The first draft recommended deleting it. That was wrong twice over. ADR
0004's last consequence had already designed the implementation — a loopback TCP bridge for the relay, and
"the same bridge provides ProxyJump via a SOCKS5 dynamic forward", one mechanism and two features — which
the pinned SSH.NET 2025.1.0 supports through ForwardedPortDynamic and ProxyTypes.Socks5, checked in
Renci.SshNet.xml rather than remembered. And the stored shape is right: an ordered list of host ids is what
a chain is, the merge arm is correct, and the missing schema version is a line to add.

◆ Looking properly found the same shape one field over, where it costs something. RelayEnabled is also
stored, merged and never read by the connect path — but it is user-settable, and both heads draw a checkbox
promising it. Ticking it moves the host's address and port out of the encrypted payload into plaintext
columns, which ADR 0004 calls the single deliberate concession in the design, and then the client dials
directly anyway. The privacy is spent and the feature is not delivered. That is a defect rather than a gap,
and it is step 0.

The comparison the plan turns on: the relay reaches what the *deployment* can reach and the jump host
reaches what a *machine in the keychain* can reach, so they are not substitutes. On a self-hosted box
outside the target's network the relay reaches nothing the laptop could not. And the privacy ordering is
the opposite way round from the ADR's framing — the relay costs a plaintext address, the jump host costs
nothing, because the operator is not in it.

Both documents carry a section on what their own earlier reasoning got wrong, which for the second one is
the load-bearing part: "nothing reads this field" was read as evidence of a mistake when it was evidence of
an unfinished feature — and the same sentence one field over would have found the checkbox that is lying.
2026-08-07 08:44:21 +02:00