[WSLC] One-shot vs state-aware network-policy parity: fail-open redundant host lists and dropped portMappings #824

Relevant area(s)

Windows (WSLc backend)

Brief description of your issue

The one-shot WSLc flow (WSLContainerRunner::start_container) and the state-aware WSLc flow (WslcStateAwareRunner + daemon) diverge on two networking behaviors that should be identical. A full one-shot-vs-state-aware policy comparison found filesystem handling is identical and the cooperative proxy is enforced identically (same apply_cooperative_proxy_env on the workload; only the declaration site differs, which is structural and acceptable). Two real gaps remain:

Gap 1 — Redundant host lists are handled inconsistently (fail-open in one-shot).
Both flows already reject meaningful per-host filtering at parse time (config_parser.rs:1064, needs_host_filtering(), added in #681). But a redundant host list — defaultPolicy: "block" + blockedHosts, or defaultPolicy: "allow" + allowedHosts — passes that gate (needs_host_filtering() → false):

• One-shot validate_runner (wsl_container_runner.rs:636) also uses needs_host_filtering(), so it accepts and silently ignores the list.
• State-aware reject_host_filtering (policy.rs:115) rejects on any non-empty list.

This is a fail-open footgun: a user who writes defaultPolicy: "allow" + allowedHosts: ["github.com"] (a classic "I meant an allowlist" typo) gets all egress permitted in one-shot, with no error — the opposite of intent.

Gap 2 — State-aware silently drops experimental.wslc.portMappings.
One-shot forwards ports (wsl_container_runner.rs:1491 → WslcSetContainerSettingsPortMappings). The state-aware provision config WslcProvisionPhase (wire.rs:550) deliberately omits portMappings, and because the experimental block is permissive (no deny_unknown_fields), a state-aware config carrying portMappings is silently ignored — no inbound forwarding, no error (container_steps.rs:803 create_daemon_container passes &[]).

Steps to reproduce

Gap 1:

1. Run a one-shot WSLc config with network: { "defaultPolicy": "allow", "allowedHosts": ["github.com"] }.
2. Observe the container starts and all egress is permitted (the allowedHosts list is ignored).
3. Run the same policy through the state-aware provision phase — it is rejected with policy_validation.

Gap 2:

1. Run a one-shot WSLc config with experimental.wslc.portMappings — the host→container port forward is configured.
2. Provide the same portMappings to a state-aware provision config.
3. Observe no port forwarding is set up and no error is raised.

Expected behavior

• Gap 1: Both flows handle host lists identically, failing closed — any non-empty allowedHosts/blockedHosts on WSLc is rejected (WSLc cannot enforce per-host filtering).
• Gap 2: Both flows support experimental.wslc.portMappings, or state-aware explicitly rejects it rather than silently ignoring it.

Actual behavior

• Gap 1: One-shot accepts and silently ignores redundant host lists (fail-open); state-aware rejects any non-empty list. Behavior differs.
• Gap 2: One-shot forwards ports; state-aware silently drops portMappings.

Proposed actions

Gap 1 — make one-shot reject (align both flows to fail-closed):

• Change the shared parser predicate config_parser.rs:1064 from policy.needs_host_filtering() to reject any non-empty allowed_hosts/blocked_hosts for WSLc; reword the error message (drop the "allowedHosts with defaultPolicy='block'…" framing).
• Mirror the same predicate in one-shot validate_runner (wsl_container_runner.rs:636) for the parser-bypass path.
• Flip the redundant-list tests (config_parser.rs WSLc host-filtering tests, wsl_container_runner.rs validate_runner_* tests) to expect rejection; keep the bare-defaults-accepted tests.
• State-aware reject_host_filtering (policy.rs:115) already matches — no change.

Gap 2 — make state-aware support portMappings (align to one-shot):

• Add port_mappings to WslcProvisionPhase (wire.rs:550) and regenerate the dev schema + SDK wire types (mxc_schema_gen).
• Add port_mappings: Vec<PortMapping> to the daemon ProvisionConfig (daemon_protocol.rs:75).
• Thread it: state_aware.rs::provision → ProvisionConfig → session_manager.rs → create_daemon_container (container_steps.rs:803), passing the slice into ContainerSettings::build (already supports port_mappings, container_steps.rs:499) instead of &[].
• Add the SDK type (sdk/node/src/state-aware-types.ts WslcProvisionConfig) and an E2E state-aware port-mapping config.

Both are self-contained: Gap 1 is tiny (one predicate + tests); Gap 2 is a field threaded through the daemon wire protocol into container creation.