feat(plc): ephemeral soft-PLC provisioning + program load (#183)

Dynamic PLC testing without reaching the customer's device: when a PLC/SPS
target ships control logic but no reachable live URL, instantiate that logic
ourselves on a throwaway OpenPLC container in-cluster, load + start it, probe
the provisioned Modbus endpoint, and tear it down. No customer network access,
sandboxed, and reproducible.

This is the phase-1 foundation of epic #183 (OpenPLC substrate). It covers:

- provision: ephemeral container lifecycle (docker CLI). Resource-capped
  (memory/cpus/pids), hardened (no-new-privileges), labelled, joined to the
  agent's own network with no host port exposure, and swept by a stale reaper
  for anything a crashed run leaks. The `docker` argv is built by pure functions
  so it is unit-tested without a daemon.
- openplc: drives the OpenPLC web UI to load a program — login → upload →
  save → compile (MatIEC) → start_plc (which opens Modbus/TCP 502).
- runtime::provision_and_test: composes them under a hard deadline with
  guaranteed teardown on every path (success / error / timeout), then runs the
  existing ICS probe against the provisioned endpoint. extract_program picks the
  best loadable program (complete ST > largest ST > PLCopen XML).
- orchestrator: for a PlcSps target with control logic and no live URL, run
  provision-and-test after the static PLC scan. Gated by PlcRuntimeConfig
  (PLC_RUNTIME_ENABLED, default off — needs Docker access in the agent).

DAST-against-WebVisu and CODESYS-runtime fidelity are follow-ups.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

compliance-core/src/config.rs

@@ -49,6 +49,57 @@ pub struct AgentConfig {
     /// of tenants to iterate. When `None` or unreachable, scheduler
     /// falls back to `SCHEDULER_TENANT_IDS` env (M7.2-C).
     pub tenant_registry_url: Option<String>,
+    /// Ephemeral soft-PLC provisioning for dynamic PLC testing (#183). Off by
+    /// default: it needs Docker access in the agent's runtime, which is a
+    /// deployment opt-in.
+    pub plc_runtime: PlcRuntimeConfig,
+}
+
+/// Configuration for the ephemeral soft-PLC "provision-and-test" path (#183).
+///
+/// When a PLC/SPS target ships control logic but no reachable live device, the
+/// agent can instantiate that logic itself: spin up a throwaway soft-PLC
+/// (OpenPLC) container in-cluster, load the program, start the runtime, probe it
+/// over industrial protocols, then tear it down. This struct carries the knobs
+/// for that container's lifecycle and the OpenPLC web-UI credentials used to
+/// upload the program.
+#[derive(Clone, Debug)]
+pub struct PlcRuntimeConfig {
+    /// Master switch. Provision-and-test does nothing unless this is set — it
+    /// shells out to `docker`, which requires the agent container to have Docker
+    /// access (socket mount), an explicit deployment decision.
+    pub enabled: bool,
+    /// Container image for the ephemeral soft-PLC (OpenPLC).
+    pub image: String,
+    /// Docker network the instance joins. Must be the agent's own network so it
+    /// is reachable in-cluster by container name and never published to the host.
+    pub network: String,
+    /// Memory cap passed to `docker run --memory` (e.g. `512m`).
+    pub memory: String,
+    /// CPU cap passed to `docker run --cpus` (e.g. `0.5`).
+    pub cpus: String,
+    /// Hard ceiling on a provisioned instance's lifetime. Teardown is guaranteed
+    /// no later than this even if a load/probe step hangs.
+    pub max_lifetime_secs: u64,
+    /// OpenPLC web-UI username for the program upload (image default `openplc`).
+    pub openplc_user: String,
+    /// OpenPLC web-UI password (image default `openplc`).
+    pub openplc_password: SecretString,
+}
+
+impl Default for PlcRuntimeConfig {
+    fn default() -> Self {
+        Self {
+            enabled: false,
+            image: "registry.meghsakha.com/openplc:latest".to_string(),
+            network: "certifai".to_string(),
+            memory: "512m".to_string(),
+            cpus: "0.5".to_string(),
+            max_lifetime_secs: 180,
+            openplc_user: "openplc".to_string(),
+            openplc_password: SecretString::from("openplc".to_string()),
+        }
+    }
 }
 
 #[derive(Clone, Debug, Serialize, Deserialize)]

compliance-core/src/lib.rs

@@ -13,6 +13,6 @@ pub mod auth;
 #[cfg(feature = "axum")]
 pub mod tenant_ctx;
 
-pub use config::{AgentConfig, DashboardConfig};
+pub use config::{AgentConfig, DashboardConfig, PlcRuntimeConfig};
 pub use error::CoreError;
 pub use tenant::{OrgRole, TenantContext, TenantStatus};