fix(acl): allow Honey to reach MCP proxies (TIN-2940)

.github/workflows/ci.yml

@@ -77,6 +77,9 @@ jobs:
           print(f'  {len(p[\"tagOwners\"])} tag owners')
           "
 
+      - name: Policy contract tests
+        run: python3 -m unittest discover -s tests -p 'test_*.py'
+
       - name: Upload policy artifact
         uses: actions/upload-artifact@v4
         with:

constants.dhall

@@ -26,6 +26,7 @@ let tag =
       , services = "tag:services"
       , k8s = "tag:k8s"
       , k8s_operator = "tag:k8s-operator"
+      , mcp_proxy = "tag:mcp-proxy"
       , tsidp = "tag:tsidp"
       , dev = "tag:dev"
       , staging = "tag:staging"

fragments/core.dhall

@@ -33,6 +33,10 @@ let tagOwners
         , mapValue =
           [ C.tag.k8s_operator, C.autogroup.admin, C.group.dollhouse_admins ]
         }
+      , { mapKey = C.tag.mcp_proxy
+        , mapValue =
+          [ C.tag.k8s_operator, C.autogroup.admin, C.group.dollhouse_admins ]
+        }
       , { mapKey = C.tag.tsidp
         , mapValue = [ C.autogroup.admin, C.group.dollhouse_admins ]
         }

grants.json

@@ -31,6 +31,10 @@
 	"app": {"tailscale.com/cap/secrets": [
 		{"action": ["get", "info", "put", "activate", "delete"], "secret": ["*"]}
 	]}
+}, {
+	"src": ["tinyland-honey"],
+	"dst": ["tag:mcp-proxy"],
+	"ip": ["tcp:8080"]
 }, {
 	"src": ["tag:dollhouse"],
 	"dst": ["tag:dollhouse"],

tests/test_policy_contract.py

@@ -0,0 +1,36 @@
+import json
+import unittest
+from pathlib import Path
+
+
+POLICY = Path(__file__).resolve().parents[1] / "generated" / "policy.json"
+
+
+class PolicyContractTest(unittest.TestCase):
+    @classmethod
+    def setUpClass(cls) -> None:
+        cls.policy = json.loads(POLICY.read_text(encoding="utf-8"))
+
+    def test_kubernetes_operator_owns_mcp_proxy_tag(self) -> None:
+        owners = self.policy["tagOwners"]["tag:mcp-proxy"]
+        self.assertIn("tag:k8s-operator", owners)
+
+    def test_honey_mcp_access_is_tcp_only_and_tag_scoped(self) -> None:
+        expected = {
+            "src": ["tinyland-honey"],
+            "dst": ["tag:mcp-proxy"],
+            "ip": ["tcp:8080"],
+        }
+        self.assertEqual(self.policy["grants"].count(expected), 1)
+
+    def test_honey_does_not_receive_broad_kubernetes_acl_access(self) -> None:
+        broad_rule = {
+            "action": "accept",
+            "src": ["tinyland-honey"],
+            "dst": ["tag:k8s:8080"],
+        }
+        self.assertNotIn(broad_rule, self.policy["acls"])
+
+
+if __name__ == "__main__":
+    unittest.main()