- new private channel_cap module: per-session active-channel count;
admit (check+increment at accept sites) / has_room / saturating
release, single-writer (inline packet-loop hooks), unit-tested
- handler wires the cap at every channel_open_* hook: the session
accept path admits-and-counts at the accept point; the tunnel rows
cap-gate before the seam stub (a counted-but-unopened stub would
leak the cap); x11 never consumes a count; the count releases
through the new channel_close hook
- dispatch::cap_exceeded_open_decline -> AdministrativelyProhibited
(the assembly's policy ceiling; OpenSSH MaxSessions parity)
- bounded-resources contract rows: cap reached -> clean decline,
close -> recovery open succeeds (wire-order deterministic),
zero cap refuses without poisoning, exhausted cap answers the
tunnel row with the cap reason; max_auth_attempts verified
behaviorally (within-ceiling failures keep the advertisement, the
past-ceiling attempt is the NoMoreAuthMethodsAvailable teardown);
window/packet/buffer/inactivity knobs recorded as covered by the
config-mapping tests
- max_exec_command_len stays carried, not enforced (wave-3 grammar)
Verification: cargo test (default), --features session / git /
tunnel / --all-features, clippy --all-targets (-D warnings, also
--all-features), fmt --check, cargo doc --no-deps - all green
- src/serve.rs (new): the ADR-006 decision-4 mechanics in code —
spawn_serving_path (the one choke point; nothing awaited inline)
and report_exit_status_then_close (exit-status before close via
the cloned Session::handle()), #[doc(hidden)] contract-test
re-exports; a unit row pins spawn-returns-while-pending.
- src/handler.rs: the four session-row seam stubs became spawned
serving paths (failure-then-close unchanged; stubs are plain fns —
an async stub holding &Session across the spawn is non-Send); open-
level declines and the tunnel seam stub stay inline by class, per
the new module-doc section.
- tests/spawn_return.rs (new): two end-to-end wire rows — the client
observes exit-status(7) strictly before close and after the handler
returned; the handler-returns-fast row routes follow-up traffic
while the serving path is still gated (POC-3 deadlock inversion).
- tasks/implementation/w2-spawn-return.md — completed with notes.
Verification (all green): cargo test; per-feature dispatch matrices
(--features git/session/tunnel/sftp, --all-features); cargo clippy
--all-targets/-all-features with -D warnings; cargo fmt --check;
cargo doc --no-deps (no warnings); taskgraph validate.
- auth_publickey: ed25519-only gate → single fingerprint path →
resolve_from_fingerprint → accept-with-identity (stored per-
connection, read by wave 3) / reject fail-closed; the gate is
explicit-over-inherited (ADR-002 decision 4) and precedes resolution
- auth_publickey_offered: explicit accept-and-delegate (counting
stays honest, POC-1)
- auth_none / auth_password / auth_keyboard_interactive /
auth_openssh_certificate: four explicit family-contract declines
- username carried by no hook — resolution is fingerprint-only (OQ-03)
- SessionHandler constructible via #[doc(hidden)] re-export (the
w2-server-mount note's widening); resolve_bridge structured out of
the #[non_exhaustive]-arg hooks so contract tests drive the bridge
core directly
- tests/auth_bridge.rs: 21 rows — wire rows over the real adapter
mount (accept, fail-closed reject, username independence, revoke
between attempts, none/password/certificate declines) + direct
rows over the wave-1 doubles
- cert fixture (throwaway ca + alpha-cert.pub) recorded in
fingerprints.txt; MemHostKeySource double in tests/common
Verification: cargo test (76 across the suite), --all-features,
clippy --all-targets (both feature sets, -D warnings), fmt --check,
doc --no-deps, taskgraph validate — all green
The `w1-test-doubles` task: the in-memory seams every later wave's
contract tests run against, behind their production seams.
- tests/common/mod.rs — the doubles, test-only (nothing reachable from
lib.rs, no feature): MemIdentityProvider (registered fingerprints ->
alkcall Identity resolutions over the IdentityProvider trait; token
path resolves none per ADR-004), TestVault (a wrapper over alkvault
0.1's shipped in-memory construction — resolving the flagged
vault-double question: wrap, not re-impl), MemHostKeyPolicy
(exact (host, fingerprint) rules + explicit default verdict,
fail-closed by default, inspectable decision log), and the fixture
table. Module docs record the location/vault/fixture decisions and
the row/stamp discipline (greppable Contract stamps).
- tests/vectors/ — one unified fixture set: four ssh-keygen-minted
ed25519 keypairs (committed .key + .pub + fingerprints.txt recorded
from ssh-keygen -lf, OpenSSH_9.6p1). The previous inline PEM
constants in src/key_source.rs were rejected by OpenSSH itself
(russh-only decodable); all keys were re-minted and the overlapping
vector set retired — one fixture set now serves the parity tests,
the custody round-trip, and every later auth/mapping test
(src-unit tests share it via include_str!).
- tests/doubles.rs — the end-to-end rows: register -> resolve,
seal -> source -> decode (+ locked/absent/tampered postures),
host-key set in order, policy verdicts honored-and-logged.
- tests/fingerprint_parity.rs and src/key_source.rs tests moved onto
the shared fixture files; src changes are #cfg(test) only.
Verification: cargo test (33 + 9 + 5 green; --all-features also green),
cargo clippy --all-targets -- -D warnings clean, cargo fmt --check
clean, taskgraph validate ok (12 tasks).