A .zddc may now declare `acl.inherit: false` to fence off ancestor
grants and roles from the descendant subtree — the "complete reset
plus add back" pattern operators want for vendor folders and other
narrowly-scoped subtrees. The cascade walker honors the deepest fence
in [0, toIdx] when evaluating any level at-or-below it, both for
GrantedVerbsAtLevel/EffectiveVerbsRange and for role lookup
(RoleMembers / lookupRoleMembers).
Federal/strict cascade mode IGNORES the fence — required by
NIST AC-6 ("ancestor deny is absolute; no leaf-level override"). So
inherit:false has no effect under strict mode and ancestor grants
remain visible. Operators running the federal Rego preset get the
same behaviour from external policy enforcement.
API surface: ACLRules.Inherit (*bool, nil = unset = inherit-true);
ACLRules.InheritsAncestors() bool; PolicyChain.VisibleStart(toIdx,
mode) int. The mode parameter is now threaded through
GrantedVerbsAtLevel, MatchesPrincipal, MatchingPrincipals,
RoleMembers, and lookupRoleMembers so role resolution is fence-aware.
Tests:
- file_test.go: parser round-trip for absent / true / false inherit
- inherit_test.go: VisibleStart (no fence, fence clamps, nested fences,
strict-mode override), EffectiveVerbs (fence hides ancestor grants,
strict-mode keeps them), RoleMembers (ancestor roles hidden by fence,
local redefinition still works)
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
ZDDC
2ccd72fa35