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# Decision-record contract
Status: published
Contract: `flex-auth.decision-record.v1`
Schema: [`../schemas/decision_envelope.schema.json` ](../schemas/decision_envelope.schema.json )
Date: 2026-09-02
This is flex-auth's output artifact under the NetKingdom Security Layer Model
v0.7 §17. Taxonomy holds only the shared field vocabulary. Consumers may rely
on this schema.
A decision record is a `DecisionEnvelope` returned by `POST /v1/check` and the
CLI `check` / `batch-check` / `list-allowed` commands. Standalone evaluation
and every delegated adapter (Topaz, relationship, rule, Keycloak) emit the
same shape.
## Required fields
| Field | Meaning |
| --- | --- |
| `id` | Deterministic decision identifier |
| `effect` | `allow` , `deny` , `redact` , `audit_only` , or `not_applicable` |
| `subject` / `resource` | Normalized refs the evaluator used |
| `provenance` | Who evaluated, over which policy and facts |
## Contract fields consumers may rely on
| Field | Meaning |
| --- | --- |
| `contract_version` | `flex-auth.decision-record.v1` |
| `binding` | Structured subject, action, resource, context, and `request_digest` |
Publish approval_binding_digest: a claim cannot name the request carrying it
secrets-engine confirmed T03, and re-verifying against the regenerated
destroy fixture found something neither repository can fix alone: a
pdp_digest recorded at issue time can never equal the request_digest of a
request that carries the claim in its context, because the claim is part
of the context that is hashed. Embedding the claim changes the very
digest the claim would need to name.
Not fixture staleness. It holds for every dual-control request whose
claim travels in context -- the shape GH-DEC-2026-008 had just ruled
mandatory. Left unresolved that ruling was unimplementable for exactly
the case it was written for, and destroy would have been permanently
un-allowable in production, failing closed forever on a check that could
never pass.
flex-auth owns the canonical request digest, so the fix is ours.
binding.approval_binding_digest is the same material with
context.approval removed, emitted only when a claim was carried. An
approval issued against a claim-free Check records that Check's
request_digest; the claim-bearing request reproduces it here.
DELIBERATELY ADDITIVE, and the reason matters. The tempting fix is to
drop context.approval from request_digest entirely. That is wrong:
request_digest is the replay identity, and two requests differing only in
which approval was presented must not share one, because their decisions
differ -- one allows, the other denies dual_control_required. Collapsing
them would let an allow obtained with a valid claim be replayed against a
request carrying none. So request_digest still covers the claim and still
moves; approval_binding_digest deliberately does not, and is documented
as not a replay identity. The tests assert the two functions DISAGREE on
a claim-bearing request, which is approval-engine's formulation of how to
defend a distinction that looks like duplication.
The fixture now demonstrates the property rather than asserting it: its
claim's pdp_digest equals the envelope's approval_binding_digest with
pdp_path true, and changing the claim's contents moved request_digest
while leaving approval_binding_digest untouched. Two files a consumer can
diff.
Also picked up approval-engine's new required binding.pdp_path via the
cross-repo schema test added yesterday -- which is the test doing exactly
what it was built for, one day later.
T03 is done. secrets-engine's own digest-material defect, which our two
real envelopes caught, is recorded in the workplan.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JTbVXpEiXA7mNJVpDnEPcB
Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 412054@bnt-lap001
Assistant-Session: 3968fae1-8d59-4209-9bd6-c22594b8ab19
2026-09-06 14:52:33 +02:00
| `binding.approval_binding_digest` | Present only when the request carried `context.approval` . The digest an approval's `pdp_digest` must equal — see [`canonical-request-digest.md` ](canonical-request-digest.md ). Not a replay identity |
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| `lifetime` | **Required on every allow.** A TTL with `not_before` and `expires_at` |
| `provenance.policy_package` / `policy_version` | Named package pin |
| `provenance.policy_package_digest` | SHA-256 of package metadata plus compiled Rego |
| `provenance.registry_snapshot_digest` | SHA-256 of the canonical registry snapshot |
| `provenance.directory_etag` | Directory consistency token when a delegated directory was joined |
| `provenance.input_claim_digests` | SHA-256 per request-time claim class (`context` , `caring_context` ) |
| `provenance.decision_time` | UTC timestamp used to compute `lifetime` |
`reason` , `diagnostics` , and CARING prose are not an authorization contract.
## Allow lifetime
Every allow carries `lifetime.kind = ttl` . The duration comes from the policy
package `allow_ttl` field, or from the engine default of `15m` when the package
omits it. A package that declares `allow_ttl: none` (or `0s` ) produces a deny
with reason `allow_lifetime_unstated` instead of a standing grant.
Replay is permitted only while `lifetime.expires_at` is still in the future.
See [`canonical-request-digest.md` ](canonical-request-digest.md ) and
[`decision-input-freshness.md` ](decision-input-freshness.md ).
## Versioning
This is contract version 1. Additive optional fields may appear. Removing or
redefining a required field requires a new `contract_version` value and a new
schema id.
fix: the address we published was a misdirection, and the channel is unauthenticated
secrets-engine probed the Service DNS name handed over in FLEX-WP-0021-T05
and found it resolves, from the workstation, to an unrelated public host.
Reproduced here: search ad.binect.de answers wildcard, so
flex-auth-secrets-engine.flex-auth.svc.cluster.local and
this-service-does-not-exist.flex-auth.svc.cluster.local both resolve to
80.158.43.29, while the trailing-dot FQDN correctly fails. A bare Service
name in a handover is not merely unreachable from there, it is a live
misdirection, and the handover was ours.
Had a deployment pointed at it, the CheckRequest body would have gone to
that host: subject, tenant, lane and resource ids, stage, field names,
purpose, plus the caller's bearer token.
Trailing-dot FQDN and "in-cluster only" now replace the bare name in the
example README, SCOPE.md, and the T05 note.
Their real question was how the response channel is authenticated, and
they declined to answer it locally because choosing a transport control
for our service is not a consumer's call. Right boundary, so the answer
is recorded here as FLEX-DEC-2026-010: it is not authenticated. Pins
serve plain HTTP, the envelope carries no signature, and a responder that
knows the package id and version can return a well-formed allow that
passes every check a consumer performs.
The part worth stating in the contract is that the digests do not help
and look like they do. Every input to request_digest,
policy_package_digest and registry_snapshot_digest is either sent by the
caller or published in this repo, so a forger reproduces all three
exactly. They establish integrity of the binding, never authenticity of
the source — and publishing more digests makes a forged envelope look
more authenticated, not less.
For secrets-engine specifically: fail-closed protects against a PDP that
is absent, not against one that lies. An unreachable PDP denies; a lying
PDP allows.
Third instance of one seam in three decisions. 008: a tenant carried
into the digest and never compared — visible, not enforced. 009: a caller
authenticated and never recorded — enforced, not visible. 010: a record
verifiable and unauthentic — checkable, but not evidence.
One nuance that changes the operator recommendation: kubectl port-forward
does authenticate the responder, transitively — no DNS name, one named
pod, API-server TLS. That is the exact reverse of the caller direction,
where it bypasses the NetworkPolicy. Independent properties pointing
opposite ways, so neither can be summarised as "the network protects it".
FLEX-WP-0024 carries signing; key custody routes through warden/OpenBao
rather than minting a key here.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014aQMM1dPXaPiXVn6DwwtLd
Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 715613@bnt-lap001
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2026-09-06 22:44:45 +02:00
## What this record does not prove: who answered
**A consumer must not read digest recomputation as verification of the
responder.** Recomputing `binding.request_digest` ,
`provenance.policy_package_digest` , and `provenance.registry_snapshot_digest`
and finding all three correct says nothing about who produced the envelope.
Every input to those digests is either sent by the caller or published: the
request material is what the caller just transmitted, and both the package and
registry digests are computable from files in this repo. A responder that knows
the package id and version can reproduce all three exactly. The digests
establish **integrity of the binding** , never **authenticity of the source** .
`flex-auth.decision-record.v1` carries no signature today, and pins serve plain
HTTP. So the response channel is unauthenticated, stated as a stance rather than
left as an assumption (`FLEX-DEC-2026-010` ). For a fail-closed consumer the
distinction that matters is this: **fail-closed protects against a PDP that is
absent, not against one that lies.** An unreachable PDP denies; a lying PDP
allows.
A detached signature over the canonical envelope is the intended fix
(`FLEX-WP-0024` ). Until it lands, responder authenticity comes from the channel
alone — and of the available channels only `kubectl port-forward` supplies it,
by targeting one named pod over the API server's TLS with no DNS name resolved.
