When the store re-read failed or timed out, introspect fell through to the
unchanged-secret branch and logged "the stored OIDC client secret is the one
the IdP refused" after the re-read's own failure line. The re-read now says
whether it read the store, and a failed one denies without the second line.
The verdict is unchanged.
The re-read of the responder's own OIDC client secret had no timeout:
neither swarm-secret-client nor vaultrs nor reqwest sets one by default,
and while a re-read runs every later refusal joins it rather than
starting another. A store connection whose peer stays alive but silent
therefore held off rotation pickup indefinitely. The spawned re-read
now gives up after 10 s, logs that it did (without the secret), keeps
the secret in use, and frees the slot for the next refusal's re-read.
The link from a non-2xx introspection (identify_caller's
`Answer::Refused`) to that re-read had no test: every existing test
handed `OidcSecret::introspect` an `Answer` directly. A new test runs
the real `identify_caller` against a loopback IdP that answers 401 to
the old secret and admits the new one, so mapping a non-2xx to
anything but `Refused` turns it red. axum is a dev-dependency for that
stub, as in swarm-controller's forge tests.
The responder reads its OIDC client secret at
`swarm/services/<client-id>/oidc/client` with the store login it already
opens for the callout keys, and holds it in memory. `--client-secret-file`
is removed.
When introspection answers non-2xx, the responder re-reads the secret from
the store once and, if it changed, retries the introspection once. Both fit
inside the request's 1.5s introspection budget, under the server's 2s
callout timeout: the budget is now one deadline for the whole request. A
re-read that does not finish by then keeps running in the background, the
request is denied, and the next request introspects with what it read. One
re-read runs at a time; a refusal while one runs waits on it.
In swarm-nats.nix the `swarm-bao-nats-auth-oidc` fetch unit, the flag and
the `oidc-client.secret` LoadCredential entry are gone, along with the
unit's policy ordering in glue-bao-readers-policy-order.nix. A tmpfiles `r`
rule removes the copy a container still holds at
/var/lib/nixos-containers/swarm-nats/var/lib/swarm-nats-auth/oidc-client.secret;
nothing reads it.
No policy change: the `swarm-nats-auth` role already reads this path
(`natsAuthReaders` in swarm-bao.nix), which is the role the removed fetch
unit logged in as.
Deploy order: none, and no operator step. The store's grant already exists,
so the queue host can be deployed before, after or without the store's host
and authelia's. Rolling back re-creates the fetch unit and the file; the
store leaf is untouched.
