The per-session random write SID forced a full tree propagation per
session per server lifetime (minutes on large workspaces). The write
SID is now the per-workspace identity derived from the canonical
workspace path (workspaceWriteSid: sha256 -> S-1-4-x-y), stored
nowhere: the workspace-root ACE materializes once per workspace per
machine and every later provision hits the exact-ACE skip.
- workspace ACEs are STANDING (never revoked - the reuse cache); temp
ACEs stay revocable (disposed with the provider), so an inheritable
ACE never outlives its session's temp dir on the ambient temp root
- AclSandbox requires the write SID under workspace-write; read-only
parses/grants nothing; the runner derives the SID itself (the
--write-sid flag's presence still marks the seam-managed contract)
- the acl-session record drops writeSid (sessionId/workspace/tempDir
remain): the SID-tamper surface and its validation are gone
- sandbox-local holds two grant maps: standing workspace grants and
revocable per-session temp grants
Docs (README pair, design note pair, catalogs, type-equiv) and the
acl-session/grant/acl/probe/runner suites updated; workspace-sid.spec
pins the derivation contract.
Huanqi Cao
5fea4b7c4b