Bind deliver-secret reference to the admitted case (NK48-R2-F2)

build() now takes case_source, checks it against admitted.pins.case, refuses
non-confidential cases and a client_id differing from the admitted target, and
derives sso/keycape-{client_id}-client (key client-secret) from
platform/workloads/keycape/{client_id} per type 1.2. No caller-chosen
reference remains. Fixtures use the 1.2 forgejo example and real names;
regression tests cover the reviewer's forgejo/grafana demonstration, a public
client and a case-pin mismatch.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 903097@bnt-lap001
Assistant-Session: aa320c8f-c3fa-46e7-8541-0b58e1e45d23

sso-mfa/k8s/keycape/deliver-secret-adapter.md

@@ -11,8 +11,14 @@ owner `railiance-platform`, lane `platform-secret-delivery`, target parameter
 `client_id`, allowed created object `delivered-secret`, `retry_safe: false`,
 revocation scope `parent-session`.
 
-It binds one admitted invocation to one Secret reference (namespace, name,
+It binds one admitted invocation to one Secret reference. `build()` takes
-custody *reference*, key names). It never reads, mints or templates a value.
+`case_source` and refuses unless its digest equals `admitted.pins.case`, the
+case is `client_type: confidential`, and its `client_id` equals the admitted
+target (as `mint-secret` and `bind-env` do). The reference is then derived from
+the admitted target per type 1.2, never chosen by the caller: ExternalSecret
+`sso/keycape-{client_id}-client`, key `client-secret`, from custody
+`platform/workloads/keycape/{client_id}` (NK48-R2-F2). Owner receipts must name
+that same reference. It never reads, mints or templates a value.
 Delivery, removal, evidence publication/authentication and parent-session
 revocation are injected owner capabilities; the module itself has no CLI and
 calls no kubectl, OpenBao or registry.

sso-mfa/k8s/keycape/deliver-secret-adapter.py

@@ -13,6 +13,8 @@ import json
 import re
 from pathlib import Path
 
+import yaml
+
 from warden.case_run import Adapter, Descriptor, Invocation, OwnerResult, contained_output, digest, IDENTIFIER
 from warden.case_receipt_state import Outcome, Refused
 
@@ -20,7 +22,8 @@ ROOT = Path(__file__).resolve().parent
 SOURCE_FILES = ('deliver-secret-adapter.py',)
 REFERENCE = 'net-kingdom/deliver-secret@v1'
 CREATED = 'delivered-secret'
-NAME = re.compile(r'[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?')
+NAMESPACE = 'sso'
+KEY_NAMES = ('client-secret',)
 RECEIPT_FIELDS = {'schema', 'operation', 'namespace', 'name', 'custody_reference',
                   'key_names', 'values_emitted', 'changed', 'before', 'after'}
 
@@ -41,10 +44,21 @@ def _revision(value):
             and all(isinstance(v, str) and 0 < len(v) <= 192 for v in value.values()))
 
 
-def build(*, admitted: Invocation, case_acceptance: str, namespace: str, name: str,
+def secret_name(client_id):
-          custody_reference: str, key_names: tuple, deliver, remove, publish,
+    return 'keycape-' + client_id + '-client'
-          authenticate, revoke_session):
+
-    """Bind one admitted case to one delivered Secret reference; return a kernel Adapter.
+
+def custody_path(client_id):
+    return 'platform/workloads/keycape/' + client_id
+
+
+def build(*, admitted: Invocation, case_source: bytes, case_acceptance: str,
+          deliver, remove, publish, authenticate, revoke_session):
+    """Bind one admitted confidential-client case; return a kernel Adapter.
+
+    The Secret reference is derived from the admitted target per type 1.2:
+    ExternalSecret sso/keycape-{client_id}-client (key client-secret) from
+    bao:platform/workloads/keycape/{client_id}. No caller chooses a reference.
 
     deliver(inv, binding)->receipt and remove(inv, binding, after)->receipt are
     owner capabilities (e.g. ESO sync with readback); receipts carry metadata only.
@@ -62,22 +76,27 @@ def build(*, admitted: Invocation, case_acceptance: str, namespace: str, name: s
         raise Refused('delivery invocation boundary differs')
     if admitted.operation != 'admission' or admitted.attempt_id:
         raise Refused('expected admission invocation')
+    if type(case_source) is not bytes or len(case_source) > 262144 or digest(case_source) != admitted.pins.case:
+        raise Refused('case source pin differs')
     desc_bytes = json.dumps(asdict(desc), sort_keys=True, separators=(',', ':')).encode()
     if admitted.pins.adapter != digest(desc_bytes):
         raise Refused('descriptor pin differs')
     if not (isinstance(case_acceptance, str) and 0 < len(case_acceptance) <= 192
             and digest(case_acceptance.encode()) == admitted.pins.acceptance):
         raise Refused('acceptance evidence binding differs')
-    if not all(isinstance(v, str) and NAME.fullmatch(v) for v in (namespace, name)):
-        raise Refused('bounded secret reference required')
-    if not (isinstance(custody_reference, str) and 0 < len(custody_reference) <= 192
-            and IDENTIFIER.fullmatch(custody_reference.replace('/', '-'))):
-        raise Refused('bounded custody reference required')
-    if (type(key_names) is not tuple or not key_names or len(set(key_names)) != len(key_names)
-            or not all(isinstance(k, str) and re.fullmatch(r'[A-Za-z0-9._-]{1,64}', k) for k in key_names)):
-        raise Refused('bounded key names required')
     if not all(callable(x) for x in (deliver, remove, publish, authenticate, revoke_session)):
         raise Refused('owner delivery, evidence and revocation capabilities required')
+    with contained_output():
+        case = yaml.safe_load(case_source)
+    params = (case or {}).get('spec', {}).get('parameters', {}) if isinstance(case, dict) else {}
+    if not isinstance(params, dict) or params.get('client_type') != 'confidential':
+        raise Refused('deliver-secret applies only to confidential clients')
+    if params.get('client_id') != admitted.target:
+        raise Refused('case target differs')
+    namespace, name = NAMESPACE, secret_name(admitted.target)
+    custody_reference, key_names = custody_path(admitted.target), KEY_NAMES
+    if not re.fullmatch(r'[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?', name):
+        raise Refused('bounded secret reference required')
     binding_ref = {'namespace': namespace, 'name': name, 'custody_reference': custody_reference,
                    'key_names': list(key_names), 'client_id': admitted.target}
     records = {}

sso-mfa/k8s/keycape/test_deliver_secret_adapter.py

@@ -14,13 +14,18 @@ a = importlib.util.module_from_spec(spec)
 spec.loader.exec_module(a)
 
 KEYS = ('client-secret',)
+EXAMPLES = ROOT.parents[2] / 'security-case-type-revisions' / '1.2' / 'oidc-browser-relying-party' / 'examples'
+CASE = (EXAMPLES / 'forgejo.yaml').read_bytes()
+PUBLIC_CASE = (EXAMPLES / 'example-public-portal.yaml').read_bytes()
+SECRET_NAME = 'keycape-forgejo-client'
+CUSTODY = 'platform/workloads/keycape/forgejo'
 AFTER = {'uid': 'uid-1', 'resource_version': '3'}
 
 
 class DeliverSecretTests(unittest.TestCase):
     def setUp(self):
         desc = json.dumps(asdict(a.descriptor()), sort_keys=True, separators=(',', ':')).encode()
-        pins = Pins(digest(b'case'), digest(b'type'), digest(desc), digest(b'catalog'),
+        pins = Pins(digest(CASE), digest(b'type'), digest(desc), digest(b'catalog'),
                     digest(b'case-acceptance:test'), digest(b'run sheet'))
         self.admitted = Invocation('deliver-secret', 'railiance-platform', 'forgejo', 'human',
                                    'founder', 'platform-secret-delivery', pins)
@@ -28,16 +33,15 @@ class DeliverSecretTests(unittest.TestCase):
         self.rb = replace(self.admitted, attempt_id='attempt-two', operation='rollback')
         self.evidence, self.calls, self.revoked = {}, [], []
         self.before = None
-        self.kw = dict(admitted=self.admitted, case_acceptance='case-acceptance:test',
+        self.kw = dict(admitted=self.admitted, case_source=CASE,
-                       namespace='sso', name='keycape-client-forgejo',
+                       case_acceptance='case-acceptance:test',
-                       custody_reference='kv/keycape/forgejo', key_names=KEYS,
                        deliver=self.deliver, remove=self.remove, publish=self.publish,
                        authenticate=lambda ref, p: self.evidence.get(ref) == p,
                        revoke_session=lambda inv: self.revoked.append(inv) or 'revocation-' + inv.attempt_id)
 
     def receipt(self, operation, changed, before, after, **extra):
         r = {'schema': 'netkingdom.deliver-secret.v1', 'operation': operation, 'namespace': 'sso',
-             'name': 'keycape-client-forgejo', 'custody_reference': 'kv/keycape/forgejo',
+             'name': SECRET_NAME, 'custody_reference': CUSTODY,
              'key_names': list(KEYS), 'values_emitted': False, 'changed': changed,
              'before': before, 'after': after}
         r.update(extra)
@@ -92,14 +96,49 @@ class DeliverSecretTests(unittest.TestCase):
                 a.build(**self.kw).invoke(self.inv)
 
     def test_build_refusals(self):
-        cases = [dict(namespace='SSO!'), dict(key_names=['client-secret']), dict(key_names=()),
+        cases = [dict(case_acceptance='other'), dict(case_source=CASE.decode()), dict(publish=None),
-                 dict(case_acceptance='other'), dict(publish=None),
                  dict(admitted=replace(self.admitted, lane='other-lane')),
                  dict(admitted=replace(self.admitted, pins=replace(self.admitted.pins, adapter=digest(b'x'))))]
         for change in cases:
             with self.subTest(change=change), self.assertRaises(Refused):
                 a.build(**{**self.kw, **change})
 
+    def test_reference_derived_from_admitted_target_per_type(self):
+        a.build(**self.kw).invoke(self.inv)
+        self.assertEqual(self.calls[0], ('deliver', {
+            'namespace': 'sso', 'name': SECRET_NAME, 'custody_reference': CUSTODY,
+            'key_names': list(KEYS), 'client_id': 'forgejo'}))
+        for caller_ref in ('namespace', 'name', 'custody_reference', 'key_names'):
+            with self.subTest(caller_ref=caller_ref), self.assertRaises(TypeError):
+                a.build(**{**self.kw, caller_ref: 'x'})
+
+    def test_reviewer_demo_admitted_forgejo_grafana_delivery_refused(self):
+        grafana = CASE.replace(b'client_id: forgejo', b'client_id: grafana')
+        # Same admitted forgejo case, grafana case source: pin differs.
+        with self.assertRaises(Refused):
+            a.build(**{**self.kw, 'case_source': grafana})
+        # Admission re-pinned to the grafana source but still targeting forgejo.
+        repinned = replace(self.admitted, pins=replace(self.admitted.pins, case=digest(grafana)))
+        with self.assertRaises(Refused):
+            a.build(**{**self.kw, 'admitted': repinned, 'case_source': grafana})
+        # A grafana-shaped receipt under the forgejo admission is refused.
+        self.kw['deliver'] = lambda inv, b: self.receipt(
+            'deliver', True, None, dict(AFTER), name='keycape-grafana-client',
+            custody_reference='platform/workloads/keycape/grafana')
+        with self.assertRaises(Refused):
+            a.build(**self.kw).invoke(self.inv)
+
+    def test_public_client_case_refused(self):
+        admitted = replace(self.admitted, target='example-portal',
+                           pins=replace(self.admitted.pins, case=digest(PUBLIC_CASE)))
+        with self.assertRaises(Refused):
+            a.build(**{**self.kw, 'admitted': admitted, 'case_source': PUBLIC_CASE})
+
+    def test_case_pin_mismatch_refused(self):
+        with self.assertRaises(Refused):
+            a.build(**{**self.kw, 'case_source': CASE + b'\n# edited\n'})
+        self.assertEqual(self.calls, [])
+
     def test_attempt_binding_and_reused_evidence_refused(self):
         adapter = a.build(**self.kw)
         with self.assertRaises(Refused):