fix(macos): persist gateway CA on host

bot_bottle/backend/macos_container/infra.py

@@ -41,7 +41,7 @@ from dataclasses import dataclass
 from pathlib import Path
 
 from ... import log
-from ...orchestrator.gateway import GATEWAY_CA_CERT
+from ...orchestrator.gateway import GATEWAY_CA_CERT, MITMPROXY_HOME
 from ...orchestrator.lifecycle import (
     DEFAULT_PORT,
     DEFAULT_STARTUP_TIMEOUT_SECONDS,
@@ -52,6 +52,7 @@ from ...paths import (
     CONTROL_PLANE_TOKEN_ENV,
     HOST_DB_FILENAME,
     host_control_plane_token,
+    host_gateway_ca_dir,
 )
 from .. import util as backend_util
 from . import util as container_mod
@@ -218,6 +219,14 @@ class MacosInfraService:
             # Container-only DB volume: one kernel writes bot-bottle.db, never
             # shared with the host or another guest.
             "--volume", f"{self._db_volume}:{_DB_ROOT_IN_CONTAINER}",
+            # The DB needs a container-only ext4 volume for coherent SQLite
+            # locking, but the CA has no such constraint. Keep it in the host
+            # app-data root so infra-container recreation and Apple Container
+            # volume pruning cannot silently rotate every bottle's trust
+            # anchor (issue #450).
+            "--mount",
+            container_mod.bind_mount_spec(
+                str(host_gateway_ca_dir()), MITMPROXY_HOME),
             # Bind-mount the control-plane source (read-only); a code change
             # takes effect on relaunch with no image rebuild.
             "--mount",
@@ -261,9 +270,9 @@ class MacosInfraService:
 
     def ca_cert_pem(self, *, timeout: float = DEFAULT_CA_TIMEOUT_SECONDS) -> str:
         """The gateway's mitmproxy CA (PEM) agents install to trust its TLS
-        interception. Read out of the container (the CA lives on a
+        interception. Read through the container path backed by the persistent
-        container-internal path, not a host mount); polls because mitmproxy
+        host CA directory; polls because mitmproxy writes it a beat after
-        writes it a beat after start."""
+        start."""
         def _fetch() -> str | None:
             result = container_mod.run_container_argv(
                 ["container", "exec", self._name, "cat", GATEWAY_CA_CERT])

docs/prds/0070-per-host-orchestrator.md

@@ -324,15 +324,24 @@ re-attachment blocker distinct from #443/#445).
 
 The CA lives on the **host filesystem** at `bot_bottle_root()/gateway-ca`
 (`host_gateway_ca_dir()`), bind-mounted into the container at mitmproxy's
-confdir. This is deliberately a host bind-mount, **not a Docker named volume**:
+confdir. This is deliberately a host bind-mount, **not a container-runtime
-a named volume survives `docker rm` but is silently wiped by
+named volume**: a named volume survives ordinary container removal but can be
-`docker volume prune` / `docker system prune --volumes` during routine host
+silently wiped by Docker's or Apple Container's volume-prune commands during
-maintenance, which is exactly how the ephemeral-CA symptom shows up in
+routine host maintenance, which is exactly how the ephemeral-CA symptom shows
-practice. A path under the app-data root is never pruned by docker, and stays
+up in practice. A path under the app-data root is not managed or pruned by the
-directly inspectable and rotatable from the host. mitmproxy reuses an existing
+container runtime, and stays directly inspectable and rotatable from the host.
-CA and generates one only on first run, so the bind-mount alone gives
+mitmproxy reuses an existing CA and generates one only on first run, so the
+bind-mount alone gives
 "adopt-existing, generate-on-first-run" for free.
 
+The macOS backend uses the same host-resident CA directory and bind-mounts it
+into the consolidated Apple infra container. Its `bot-bottle-mac-db` named
+volume remains container-only because that prevents incoherent cross-kernel
+SQLite locking, but the CA is deliberately not stored there: Apple Container
+also has a `container volume prune` operation, and the named volume is
+temporarily unreferenced while the infra container is recreated. Keeping the
+CA on the host makes both ordinary recreation and volume pruning safe.
+
 **Deliberate rollover** is the explicit inverse: `rotate_gateway_ca()` removes
 the persisted CA material so the next start remints it, and the
 `python -m bot_bottle.orchestrator.rotate_ca` one-shot wires that together with

tests/unit/test_macos_infra.py

@@ -61,6 +61,20 @@ class TestInfraRun(unittest.TestCase):
         mounts = [argv[i + 1] for i, a in enumerate(argv) if a == "--mount"]
         self.assertTrue(all("bot-bottle.db" not in m for m in mounts))
 
+    def test_ca_is_persisted_on_the_host_not_the_container_volume(self) -> None:
+        """The CA survives infra recreation and cannot be removed by Apple
+        Container's volume-prune command."""
+        argv = self._run_container(MacosInfraService(repo_root=Path("/r")))
+        mounts = [argv[i + 1] for i, a in enumerate(argv) if a == "--mount"]
+        ca_mounts = [
+            m for m in mounts
+            if "target=/home/mitmproxy/.mitmproxy" in m
+        ]
+        self.assertEqual(1, len(ca_mounts))
+        self.assertIn("source=", ca_mounts[0])
+        self.assertIn("/gateway-ca", ca_mounts[0])
+        self.assertNotIn(",readonly", ca_mounts[0])
+
     def test_nat_network_precedes_the_host_only_network(self) -> None:
         argv = self._run_container(MacosInfraService(repo_root=Path("/r")))
         nets = [argv[i + 1] for i, a in enumerate(argv) if a == "--network"]