Files
stack/docs/architecture/lease-broker-security.md
ms-lead-reviewer 6a3505dfbc
All checks were successful
ci/woodpecker/pr/ci Pipeline was successful
fix(#829): gate claudex and close branch coverage gaps
2026-07-17 23:12:42 -05:00

14 lines
2.0 KiB
Markdown

# WI-1 lease broker security notes
- Trusted identity comes only from Linux `SO_PEERCRED` plus `/proc` starttime, never request identity fields.
- Descendant authorization is anchored to `(pid,starttime)` and uses a complete second starttime pass to fail closed on disappearance or PID-reuse races.
- Runtime generations are monotonic per anchor; a bump revokes prior-incarnation tokens before persistence commits.
- Session IDs and cycle tokens use the OS cryptographic RNG. `Math.random` and model output are not token sources.
- Framing and persistence failures fail closed. Sensitive tokens are not logged.
- Built-in `0700`/`0600` filesystem modes provide same-principal hardening only, not socket authenticity against the same UID. WI-1 provides no distinct-principal isolation. That stronger deployment requires an external protected proxy, ACL, or service boundary, and the boundary must preserve authenticated client identity for the broker's `SO_PEERCRED` and ancestry authorization rather than substituting a shared proxy identity.
- WI-2 whole-class authorization denies every consequential, unknown, and custom tool while UNVERIFIED; it does not inspect shell strings or trust wrapper selection. First-class Claude/Pi and both Claudex dispatch modes use broker register-before-exec; Claudex additionally installs the mandatory all-tools hook inside its preserved isolated config and fails closed on unsafe settings.
- WI-2 promotion consumes a WI-1 cycle token before VERIFIED becomes visible. Observer revocation, runtime-generation replacement, broker restart, and monotonic TTL expiry remove authority.
- Receipt observation, payload construction, compaction observers, and constrained recovery implementation remain later surfaces. A receipt can become a promotion prerequisite but is never the safety mechanism.
Coordinator security review must rerun the real socket/peercred and mutator-gate acceptance suites on an unrestricted Linux runner and obtain the mandated independent Opus-SECREV review before integration.