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Author	SHA1	Message	Date
jaap-jan	d5b1a73182	Move the keys when a membership changes, not just the flag Adding somebody to a team granted them nothing readable and removing them rotated nothing. Both were honest — the interface said so in as many words — and both left the actual work to a button somebody had to remember to press, on a machine that happened to hold the key. Adding now wraps every team vault this machine can open to the new member, and removing revokes their grants and moves each of those vaults to a fresh key that goes to whoever is left. The rotation is where the design had to be decided rather than written. A vault key is per generation and an item carries the generation it was sealed under, so advancing the vault and withdrawing the old grants would make everything already stored unreadable to everybody, including whoever pressed the button. So earlier grants are kept: a member holds one per generation, /me serves them as PriorKeyWraps, and VaultKeyring holds a key per generation — the newest for writing, the item's own for reading, chosen per item on every read path. Sharing issues one grant per generation held, because a recipient handed only the current key would open the vault to find most of it undecryptable; revocation takes every generation, because leaving the history behind leaves them able to read everything written before the rotation. The bump itself is one server transaction. POST /vaults/{id}/rekey must name exactly current + 1 and the vault's xmin token makes that binding, so two admins rotating at once do not both walk away believing they succeeded — the second is refused and told to read the vault again. The server contributes the moment and no cryptography: it cannot generate the key, cannot tell that the one it is handed differs from the old one, and checks that the caller held the old one the only way it can, by requiring a live grant at the current generation. What this does not do is re-encrypt what is already stored, and the product says so rather than the reassuring version: everything written from the rotation onwards is unreadable to the person who left, and nothing about the past changes. That half is deferred and is safe to add incrementally precisely because a vault at mixed generations stays readable. ADR 0010 records the alternatives — revoking the old grants, chaining each key under its successor, re-sealing every item in one request against a server that caps a push at 500 operations — and why each was rejected. Two things fell out of the change rather than being asked for. The grant listing would have shown a member once per generation, so it now returns one row per holder carrying the best key they hold, which is what makes a row below the vault's generation mean "still owed the new key". And MarkUnreadable gives up the write target as well as reporting: a client whose vault was rotated elsewhere would otherwise have gone on sealing items under its superseded key — readable to its author, unreadable to everybody else, with nothing to show for it.	2026-08-03 23:05:40 +02:00
jaap-jan	95816de0c5	Share a vault with a team, without the server holding a key M3's teams, sharing and ACLs. Teams with roles, a public-key directory, the append-only key log served for clients to check it against, team-owned vaults, and vault key grants wrapped by a client and stored opaquely by the server. VaultAccessService resolves team membership to PermissionFlags, so a viewer may pull and may not push; the desktop client reads and syncs every vault it holds a key for, and a real TEAMS screen replaces the one that said it did not exist. No migration: team, team_membership, vault.team_id and vault_key_grant have all been there since the first one, which is what carrying two unused tables bought. Membership is authorisation. A grant is access. The obvious model is one concept — "access", with a role attached, handed out by the server — and this architecture cannot implement it: a vault key is sealed to each member's X25519 key, and only a client holding the plaintext can seal it for somebody else. So "give Bob access" decomposes into a database write and a wrap, which happen on different machines. Adding a member makes the server serve them the vault; it cannot make it readable. VaultSummary.WrappedVaultKey is null in the meantime and the vault appears in their list saying it is waiting for a key, because hiding it until a grant existed would have been tidier and would have implied the server was the thing granting access. The screen says the same thing after every add, in the status line. ADR 0009 records the whole decision. Sharing verifies or refuses. A directory lookup is a claim by the server about a third party's public key, and wrapping to an unverified claim hands the vault to whoever made it — no amount of transport security helps, because the server is inside the threat model. KeyLogAudit reads the whole log, recomputes every entry's hash from its own contents, checks the chain from genesis, and refuses unless the offered key appears in it unchanged. There is no override flag: one that exists gets used on the day the log is briefly unreachable, and the resulting grant is indistinguishable from a correct one afterwards. What it still cannot promise is that the key is the right person's, so the fingerprint comes back for an out-of-band comparison and the success message says so every time. A test corrupts the fake server's log by one byte and watches the client refuse rather than warn. The roles are only the ones that are enforceable. There is no ConnectOnly, despite the design asking for one and TeamRole having room: SSH terminates on the client, so a session needs the credential's plaintext on that machine, and "may connect but may not read the key" cannot be enforced here. Shipping it as an option in a dropdown would have been a lie. Connect rides along with Read and is documented as an interface hint. Removal is named for what it does — it revokes grants and flags the vault for rekey, and claims nothing about what is already on somebody's laptop. Three things are deliberately absent, and each is a refusal rather than an omission. The rekey itself, because re-wrapping every item's data key under a new vault key needs a client holding the current one; the server records that a rotation is owed and the interface reports it, which is more honest than a button that only appears to do it. Ownership transfer, because allowing an owner to be removed without one leaves a team nobody can administer. And cross-vault host key trust: a pin in a team vault is listed but not consulted at connect time, because any member with Write could otherwise pre-approve a fingerprint another member's client then trusts silently for a host in their own vault. Scoping trust properly needs a scope on the SSH connect path, which IKnownHostStore has not got; until then the narrow direction is the safe one and the cost is in the README rather than hidden. Reading now spans vaults and writing still does not. Every list on the vault and hosts screens covers each vault the keyring opened, rows carry the vault they came from, and an edit goes back to that vault rather than to the active one — writing it to the active vault would fork the item and only show up when a colleague wondered why their change never arrived. A new item goes wherever a picker says, defaulting to the personal vault and never moving on its own, because an item filed into a team's vault is visible to that team and moving it back means deleting and retyping. The sidebar heading stops naming one vault once there are two, and each row names its own. The server checks what it can and nothing it cannot. It will not record a grant for a key its recipient no longer holds, for a superseded generation, or for somebody who is not in the team — each of those would otherwise surface days later at the far end as a tag failure indistinguishable from corruption. It does not verify the wrap or the signature, and the grant service says so: that would be a convenience and never the boundary, and would put an asymmetric implementation on a machine that is supposed to hold no keys. Two bugs the tests found. TeamsViewModel's busy gate blocked its own reload, so a team created a moment earlier was missing from the list it had just been added to. And syncing every vault turned a failure from an exception into a report, which made a background pass announce an unreachable vault once a minute — the exact behaviour AnAutomaticPassThatFails_LeavesTheStatusAlone exists to prevent. The fact is recorded and the message swallowed, as it was before; pressing Sync still names the vault and the reason. Also fixes a build break this branch started with: QuickConnectTests was never updated when M2 added ISftpSessionFactory to the shell's constructor, so nothing built at all.	2026-07-31 12:18:28 +02:00
jaap-jan	8d2416a602	Add the encrypted local cache and the sync client Three new client projects, and the wire-contract fix they needed. DodoSSH.Client.Domain holds the decrypted item model and the three-way merge, with no I/O at all — so the suite that decides whether a credential can be lost runs in milliseconds with nothing to mock. Scalars defer to the server on a genuine clash so every replica resolves the same triple identically and two clients cannot ping-pong; directives merge per name so two people each adding one both keep theirs; the jump chain merges as a whole value because its order is the route. Whatever loses is returned rather than dropped. DodoSSH.Client.Storage is EF Core on SQLite, no SQLCipher: the rows are already ciphertext, so an encrypted file would protect protected bytes at the cost of a native dependency. It keeps the server's state and the outbox in separate tables, which is what preserves the common ancestor a merge needs. One pending operation per item, enforced by a unique index. DodoSSH.Client.Sync is the pull/apply/push loop. Pulling never decrypts — a change with no local work pending is plumbed as ciphertext — so a first sync of thousands of items does not run twice as many AEAD operations for nothing. Contracts: EncryptedPayload gains WrappedDataKey and DataKeyId. The specification has required a per-item data key since crypto.md §3, the columns have existed since the first migration and DshAad.ItemPayload binds the id, but this record had nowhere to put either — so a spec-compliant item could not be transmitted at all. Found by writing the client that has to produce one. Also closes a hole in AadResourceType, which had no value for the HostTag and HostCredential that SyncEntityType has always listed. Four bugs the tests found, not review: - SQLite refuses to order or compare its own DateTimeOffset mapping, and throws at execution rather than model build. Collecting tombstones and listing conflicts are both that shape, so this was a crash waiting for the first user with a deleted host. Timestamps are integers now, by convention so a later field cannot be the one left unconverted. - SQLitePCLRaw 2.1.11, which EF resolves, is covered by GHSA-2m69-gcr7-jv3q. Pinned forward as a family. - Resurrecting content from a remote deletion cleared the original before queueing the copy. Two transactions, so a crash between them lost the work; reversed, and the rescued id is derived from the tombstone so a replay coalesces instead of duplicating. - Several equality assertions went through Shouldly's ShouldBe, which compares IEnumerable element-wise and so tested nothing about the Equals these types exist to provide. Corrected; the falsification that caught it went from 2 failures to 6. The push response's cursor is deliberately ignored. It sits after this client's own writes, so adopting it skips anything another client committed at a lower sequence in the window between a pull and a push — permanently. Re-reading one's own writes is idempotent and costs a page. The Contracts doc that invited the shortcut now says so. 593 tests, up from 448. The delete-versus-edit rules, the ancestor retention, the fresh operation id on coalesce and the cursor safeguard were each verified by breaking them and watching the right test fail.	2026-07-29 10:27:37 +02:00

Author

SHA1

Message

Date

jaap-jan

d5b1a73182

Move the keys when a membership changes, not just the flag

Adding somebody to a team granted them nothing readable and removing them
rotated nothing. Both were honest — the interface said so in as many words — and
both left the actual work to a button somebody had to remember to press, on a
machine that happened to hold the key. Adding now wraps every team vault this
machine can open to the new member, and removing revokes their grants and moves
each of those vaults to a fresh key that goes to whoever is left.

The rotation is where the design had to be decided rather than written. A vault
key is per generation and an item carries the generation it was sealed under, so
advancing the vault and withdrawing the old grants would make everything already
stored unreadable to everybody, including whoever pressed the button. So earlier
grants are kept: a member holds one per generation, /me serves them as
PriorKeyWraps, and VaultKeyring holds a key per generation — the newest for
writing, the item's own for reading, chosen per item on every read path. Sharing
issues one grant per generation held, because a recipient handed only the current
key would open the vault to find most of it undecryptable; revocation takes every
generation, because leaving the history behind leaves them able to read
everything written before the rotation.

The bump itself is one server transaction. POST /vaults/{id}/rekey must name
exactly current + 1 and the vault's xmin token makes that binding, so two admins
rotating at once do not both walk away believing they succeeded — the second is
refused and told to read the vault again. The server contributes the moment and
no cryptography: it cannot generate the key, cannot tell that the one it is
handed differs from the old one, and checks that the caller held the old one the
only way it can, by requiring a live grant at the current generation.

What this does not do is re-encrypt what is already stored, and the product says
so rather than the reassuring version: everything written from the rotation
onwards is unreadable to the person who left, and nothing about the past changes.
That half is deferred and is safe to add incrementally precisely because a vault
at mixed generations stays readable. ADR 0010 records the alternatives — revoking
the old grants, chaining each key under its successor, re-sealing every item in
one request against a server that caps a push at 500 operations — and why each
was rejected.

Two things fell out of the change rather than being asked for. The grant listing
would have shown a member once per generation, so it now returns one row per
holder carrying the best key they hold, which is what makes a row below the
vault's generation mean "still owed the new key". And MarkUnreadable gives up the
write target as well as reporting: a client whose vault was rotated elsewhere
would otherwise have gone on sealing items under its superseded key — readable to
its author, unreadable to everybody else, with nothing to show for it.

2026-08-03 23:05:40 +02:00

jaap-jan

95816de0c5

Share a vault with a team, without the server holding a key

M3's teams, sharing and ACLs. Teams with roles, a public-key directory, the
append-only key log served for clients to check it against, team-owned vaults,
and vault key grants wrapped by a client and stored opaquely by the server.
VaultAccessService resolves team membership to PermissionFlags, so a viewer may
pull and may not push; the desktop client reads and syncs every vault it holds
a key for, and a real TEAMS screen replaces the one that said it did not exist.
No migration: team, team_membership, vault.team_id and vault_key_grant have all
been there since the first one, which is what carrying two unused tables bought.

Membership is authorisation. A grant is access. The obvious model is one
concept — "access", with a role attached, handed out by the server — and this
architecture cannot implement it: a vault key is sealed to each member's X25519
key, and only a client holding the plaintext can seal it for somebody else. So
"give Bob access" decomposes into a database write and a wrap, which happen on
different machines. Adding a member makes the server serve them the vault; it
cannot make it readable. VaultSummary.WrappedVaultKey is null in the meantime
and the vault appears in their list saying it is waiting for a key, because
hiding it until a grant existed would have been tidier and would have implied
the server was the thing granting access. The screen says the same thing after
every add, in the status line. ADR 0009 records the whole decision.

Sharing verifies or refuses. A directory lookup is a claim by the server about
a third party's public key, and wrapping to an unverified claim hands the vault
to whoever made it — no amount of transport security helps, because the server
is inside the threat model. KeyLogAudit reads the whole log, recomputes every
entry's hash from its own contents, checks the chain from genesis, and refuses
unless the offered key appears in it unchanged. There is no override flag: one
that exists gets used on the day the log is briefly unreachable, and the
resulting grant is indistinguishable from a correct one afterwards. What it
still cannot promise is that the key is the right person's, so the fingerprint
comes back for an out-of-band comparison and the success message says so every
time. A test corrupts the fake server's log by one byte and watches the client
refuse rather than warn.

The roles are only the ones that are enforceable. There is no ConnectOnly,
despite the design asking for one and TeamRole having room: SSH terminates on
the client, so a session needs the credential's plaintext on that machine, and
"may connect but may not read the key" cannot be enforced here. Shipping it as
an option in a dropdown would have been a lie. Connect rides along with Read
and is documented as an interface hint. Removal is named for what it does — it
revokes grants and flags the vault for rekey, and claims nothing about what is
already on somebody's laptop.

Three things are deliberately absent, and each is a refusal rather than an
omission. The rekey itself, because re-wrapping every item's data key under a
new vault key needs a client holding the current one; the server records that a
rotation is owed and the interface reports it, which is more honest than a
button that only appears to do it. Ownership transfer, because allowing an
owner to be removed without one leaves a team nobody can administer. And
cross-vault host key trust: a pin in a team vault is listed but not consulted
at connect time, because any member with Write could otherwise pre-approve a
fingerprint another member's client then trusts silently for a host in their
own vault. Scoping trust properly needs a scope on the SSH connect path, which
IKnownHostStore has not got; until then the narrow direction is the safe one
and the cost is in the README rather than hidden.

Reading now spans vaults and writing still does not. Every list on the vault
and hosts screens covers each vault the keyring opened, rows carry the vault
they came from, and an edit goes back to that vault rather than to the active
one — writing it to the active vault would fork the item and only show up when
a colleague wondered why their change never arrived. A new item goes wherever a
picker says, defaulting to the personal vault and never moving on its own,
because an item filed into a team's vault is visible to that team and moving it
back means deleting and retyping. The sidebar heading stops naming one vault
once there are two, and each row names its own.

The server checks what it can and nothing it cannot. It will not record a grant
for a key its recipient no longer holds, for a superseded generation, or for
somebody who is not in the team — each of those would otherwise surface days
later at the far end as a tag failure indistinguishable from corruption. It
does not verify the wrap or the signature, and the grant service says so: that
would be a convenience and never the boundary, and would put an asymmetric
implementation on a machine that is supposed to hold no keys.

Two bugs the tests found. TeamsViewModel's busy gate blocked its own reload, so
a team created a moment earlier was missing from the list it had just been
added to. And syncing every vault turned a failure from an exception into a
report, which made a background pass announce an unreachable vault once a
minute — the exact behaviour AnAutomaticPassThatFails_LeavesTheStatusAlone
exists to prevent. The fact is recorded and the message swallowed, as it was
before; pressing Sync still names the vault and the reason.

Also fixes a build break this branch started with: QuickConnectTests was never
updated when M2 added ISftpSessionFactory to the shell's constructor, so
nothing built at all.

2026-07-31 12:18:28 +02:00

jaap-jan

8d2416a602

Add the encrypted local cache and the sync client

Three new client projects, and the wire-contract fix they needed.

DodoSSH.Client.Domain holds the decrypted item model and the three-way
merge, with no I/O at all — so the suite that decides whether a
credential can be lost runs in milliseconds with nothing to mock.
Scalars defer to the server on a genuine clash so every replica resolves
the same triple identically and two clients cannot ping-pong; directives
merge per name so two people each adding one both keep theirs; the jump
chain merges as a whole value because its order is the route. Whatever
loses is returned rather than dropped.

DodoSSH.Client.Storage is EF Core on SQLite, no SQLCipher: the rows are
already ciphertext, so an encrypted file would protect protected bytes
at the cost of a native dependency. It keeps the server's state and the
outbox in separate tables, which is what preserves the common ancestor a
merge needs. One pending operation per item, enforced by a unique index.

DodoSSH.Client.Sync is the pull/apply/push loop. Pulling never decrypts
— a change with no local work pending is plumbed as ciphertext — so a
first sync of thousands of items does not run twice as many AEAD
operations for nothing.

Contracts: EncryptedPayload gains WrappedDataKey and DataKeyId. The
specification has required a per-item data key since crypto.md §3, the
columns have existed since the first migration and DshAad.ItemPayload
binds the id, but this record had nowhere to put either — so a
spec-compliant item could not be transmitted at all. Found by writing
the client that has to produce one. Also closes a hole in
AadResourceType, which had no value for the HostTag and HostCredential
that SyncEntityType has always listed.

Four bugs the tests found, not review:

- SQLite refuses to order or compare its own DateTimeOffset mapping, and
  throws at execution rather than model build. Collecting tombstones and
  listing conflicts are both that shape, so this was a crash waiting for
  the first user with a deleted host. Timestamps are integers now, by
  convention so a later field cannot be the one left unconverted.
- SQLitePCLRaw 2.1.11, which EF resolves, is covered by
  GHSA-2m69-gcr7-jv3q. Pinned forward as a family.
- Resurrecting content from a remote deletion cleared the original
  before queueing the copy. Two transactions, so a crash between them
  lost the work; reversed, and the rescued id is derived from the
  tombstone so a replay coalesces instead of duplicating.
- Several equality assertions went through Shouldly's ShouldBe, which
  compares IEnumerable element-wise and so tested nothing about the
  Equals these types exist to provide. Corrected; the falsification that
  caught it went from 2 failures to 6.

The push response's cursor is deliberately ignored. It sits after this
client's own writes, so adopting it skips anything another client
committed at a lower sequence in the window between a pull and a push —
permanently. Re-reading one's own writes is idempotent and costs a page.
The Contracts doc that invited the shortcut now says so.

593 tests, up from 448. The delete-versus-edit rules, the ancestor
retention, the fresh operation id on coalesce and the cursor safeguard
were each verified by breaking them and watching the right test fail.

2026-07-29 10:27:37 +02:00