Several setups migrating one SQLite secret store at once (mxaccessgw's parallel test hosts on the
per-process store) failed intermittently on Windows with "cannot start a transaction within a
transaction" from SqliteSecretsStoreMigrator.MigrateAsync. That message means the BEGIN ran on a
handle that was already in a transaction: the pinned Microsoft.Data.Sqlite 10.0.7 can hand one
pooled handle to two owners (dotnet/efcore#39009, fixed in 10.0.13) and no 10.0.x refuses to
re-pool a handle whose rollback failed (dotnet/efcore#39082).
The migrator now serialises migrations of one store per process behind a gate keyed on the
normalised path, runs each attempt on a dedicated unpooled connection inside BEGIN IMMEDIATE, and
retries SQLITE_BUSY/SQLITE_LOCKED (another process past the busy timeout) with equal-jitter
exponential backoff. Store operations and the Microsoft.Data.Sqlite pin are unchanged.
Tests: concurrent-init (16 hosts x 20 rounds on fresh and existing stores, two path spellings,
16 AddZbSecrets containers running the pre-host migrator + hosted service), gate sharing/waiting,
BUSY retry past the 5 s busy timeout, transient-code classification.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
G-8 (KEK rotation) — built in ZB.MOM.WW.Secrets, lib 0.1.2->0.1.3:
- ISecretCipher.Rewrap(row, oldKek, newKek): re-wraps the per-secret DEK only
(bodies never re-encrypted; revision/timestamps preserved -> invisible to
cluster LWW). Fail-closed on wrong old-KEK id, wrong key bytes, and malformed
wraps; DEK zeroed on all paths.
- ISecretStore.ApplyRewrapAsync(rewrappedRow, expectedCurrentWrappedDek):
updates only the 4 wrap columns + kek_id, compare-and-swap on the current
wrapped DEK so a concurrent set/rotate cannot corrupt a row (closes a
review-caught TOCTOU).
- KekRotationService.RewrapAllAsync + RewrapReport: enumerate all rows incl.
tombstones, idempotent/resumable skip-already-current, bounded CAS-retry,
fail-closed on unknown/identical KEK.
- `secret rewrap-all` CLI verb: key material only via env-var name / file path,
JSON counts report; README section + operator runbook.
Verified: full offline suite green (82 core + 15 UI, 0 regressions) + end-to-end
CLI smoke + adversarial crypto review (all 7 categories PASS; TOCTOU fixed).
G-7 (clustered replication) — designed + planned, no code:
- Fork resolved to build Option A (shared SQL-Server ISecretStore); Akka
replicator ZB.MOM.WW.Secrets.Akka is a deferred phase-2. Design doc +
executable plan + .tasks.json under docs/plans/2026-07-17-secrets-g7-*.
Tracking: components/secrets/GAPS.md + CLAUDE.md secrets row updated.
Joseph Doherty