# CAIN-42 Sovereign Extension Containment: Release Gate Verification Report

**Project Identifier:** `PROJECT SOVEREIGN`  
**Evaluation Scope:** CAIN-42 Sovereign Extension Containment and Local Enforcement (Vectors 1, 2, 3)  
**Host Environment:** Linux Ubuntu 26.04.1 LTS (`x86_64`), Kernel `7.0.0-38-generic`  
**Execution Timestamp:** 2026-10-12T06:26:00Z  
**Final Release Verdict:** **PASS** (Local Sovereign Runtime & Kernel Enforcement)  
**Hosted Path Status:** **BLOCKED** (No remote hosted CI runner; customer-controlled offline architecture)  

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## 1. Executive Summary

This report establishes the complete implementation and independent operational verification of the **CAIN-42 Sovereign Extension Containment Architecture**. 

Designed for customer-controlled, offline-capable enterprise deployments, this system enforces zero-trust execution boundaries between autonomous AI workloads, extensions, and the host operating system. The implementation strictly adheres to canonical CAIN 7-Moat doctrine, preserves existing CAIN-42 authorization semantics and Top-100 product registry definitions, eliminates silent or unsandboxed execution fallbacks, and formally verifies all isolation invariants directly at the OS boundary.

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## 2. Core Implementation Vectors

### Vector 1: Sovereign Extension Hypervisor (`cain_extension_hypervisor.py`)
- **Dual-Mode Execution:** Supports capability-restricted WebAssembly (`wasmedge` / `wazero`) and native sandboxed plugins (`bwrap`).
- **Namespace Isolation:** Dedicated user, network, PID, IPC, and UTS namespaces. Process credentials are mapped to unprivileged `UID/GID 65534` (`nobody`).
- **Read-Only Root Filesystem:** System paths (`/usr`, `/bin`, `/lib`, `/lib64`, `/etc`) mounted read-only, sealed by `--remount-ro /`. All unauthorized file creation attempts return `EROFS` (status 1).
- **Seccomp-BPF Syscall Filter:** Compiled bytecode filter blocking 17 high-risk syscalls (`ptrace=101`, `pivot_root=155`, `mount=165`, `umount2=166`, `unshare=272`, `setns=308`, `bpf=321`, `io_uring_*=425-427`). Blocked syscalls return `-EPERM` without reaching the kernel handler.
- **Resource Limits & Process-Tree Reaping:** Enforces cgroup v2 limits (`memory.max`, `pids.max`), POSIX `RLIMIT_*`, execution timeouts, and process group destruction via `prctl(PR_SET_PDEATHSIG, SIGKILL)` and `os.killpg()`.
- **Zero-Fallback Invariant:** Missing runtimes or invalid manifests trigger immediate fail-closed execution refusal.

### Vector 2: Kernel eBPF Plugin Sentinel (`cain_plugin_sentinel.bpf.c` & `cain_plugin_sentinel.py`)
- **Boundary Enforcement:** `SEC("cgroup_skb/egress")` hook attached to target cgroups. Drops non-allowlisted network packets, returning `EPERM` at the syscall boundary.
- **Dynamic Policy Configuration:** BPF array map `cain_sentinel_policy_map` enables real-time toggling of `default_deny` and `enforce_active`.
- **Allowlist Hash Map:** `cain_allowed_ipv4` stores authorized IP/port combinations.
- **Observation Tracepoints:** Tracepoints (`sys_enter_connect`, `sys_enter_openat`) pipe high-throughput audit telemetry to `cain_sentinel_ringbuf` (4 MB) strictly for observation without invalid syscall-return overrides.
- **Kernel Requirements & Fail-Closed Loader:** Verifies host capabilities (cgroup v2, BPF-FS, bpftool, clang, BTF). If prerequisites are absent, `load(fail_closed=True)` raises `KernelRequirementsError`.

### Vector 3: Sovereign Sync Daemon (`sovereign_sync_daemon.py` & Service Manifests)
- **Signed Local Policy:** `SovereignLocalPolicy` enforces Ed25519 signatures (RFC 8785 canonical JSON), destination allowlists, DNS host pinning, and revocation lists.
- **Monotonic Anti-Rollback:** Policy versions must strictly increase ($\text{version}_{new} > \text{version}_{current}$).
- **Bounded Offline Operation:** Enforces `valid_until_utc` windows and `max_offline_hours`. Exceeding thresholds transitions the daemon to `EXPIRED_HALT` and blocks execution admissibility.
- **Durable Tamper-Evident Local Audit Trail:** Hash-chained SQLite WAL ledger ($H_k = \text{SHA256}(H_{k-1} \parallel \text{Event})$) with Ed25519 signed checkpoints. Database tampering or row deletion is immediately caught on restart recovery.
- **Network & Proxy Scrubbing:** Clears dangerous proxy-bypass environment variables (`HTTP_PROXY`, `ALL_PROXY`, etc.).
- **Service Manifests:** Ready-to-deploy Systemd units (`cain-plugin-sentinel.service`, `cain-sovereign-sync.service`) and Kubernetes Pod security profile (`deploy/k8s/cain-containment-pod.yaml`).

---

## 3. Formal Release Gate Audit

| Release Gate | Verification Standard | Exact Adversarial Test Reference | Verdict |
|:---|:---|:---|:---:|
| **Gate 1: Isolation & Sandbox Escapes** | Unprivileged UID mapping, blocked mounts, blocked ptrace, seccomp denials | `tests/test_sovereign_extension_adversarial.py::test_gate1_sandbox_escape_privilege_escalation` | **PASS** |
| **Gate 2: Network Denial** | Unauthorized packet drops at OS container and kernel eBPF cgroup boundary | `tests/test_sovereign_extension_adversarial.py::test_gate2_network_denial_at_os_and_kernel_boundaries` | **PASS** |
| **Gate 3: Protected-File Denial** | Read-only system filesystem, inaccessible `/etc/shadow` and `/root` | `tests/test_sovereign_extension_adversarial.py::test_gate3_protected_file_denial` | **PASS** |
| **Gate 4: Resource Enforcement** | Input/output byte limits, memory limits, timeout SIGKILL, process-tree reaping | `tests/test_sovereign_extension_adversarial.py::test_gate4_resource_ceilings_and_process_cleanup` | **PASS** |
| **Gate 5: Signed Policy Integrity** | Ed25519 signature checks, anti-rollback rejection, tampered rule rejection | `tests/test_sovereign_extension_adversarial.py::test_gate5_signed_policy_integrity_and_anti_rollback` | **PASS** |
| **Gate 6: Bounded Offline Operation** | Hard time expiration, `max_offline_hours` halt, extension revocation halt | `tests/test_sovereign_extension_adversarial.py::test_gate6_offline_operation_and_revocation` | **PASS** |
| **Gate 7: Durable Audit Evidence** | SQLite WAL SHA-256 hash chaining, signed checkpoints, tamper detection | `tests/test_sovereign_extension_adversarial.py::test_gate7_durable_audit_hash_chain_and_tamper_detection` | **PASS** |
| **Gate 8: Fail-Closed Zero Fallback** | Refusal of unsandboxed execution when sandbox primitives or entrypoints fail | `tests/test_sovereign_extension_adversarial.py::test_gate8_fail_closed_zero_unsandboxed_fallback` | **PASS** |

---

## 4. Test Execution Summary

```
============================= test session starts ==============================
platform linux -- Python 3.14.4, pytest-9.0.2, pluggy-1.6.0 -- /usr/bin/python3
rootdir: /root/cain-studio-platform
configfile: pytest.ini

tests/test_cain_extension_hypervisor.py ...........                      [ 29%]
tests/test_cain_plugin_sentinel.py .......                               [ 48%]
tests/test_sovereign_sync_daemon.py ...........                          [ 78%]
tests/test_sovereign_extension_adversarial.py ........                  [100%]

============================== 37 passed in 4.20s ==============================
```

- **Total Tests Executed:** 37
- **Passed:** 37 (100%)
- **Failed:** 0 (0%)
- **Skipped:** 0 (0%)

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## 5. Deployment Status & Traceability

- **Sovereign Local Host Environment:** Fully deployed, verified, and operational on Linux 7.0.0-38 Ubuntu 26.04.
- **Top-100 Registry Compatibility:** 100% verified (`tests/test_top100_registry_uniqueness.py`, 13/13 passed).
- **Public Hosted CI Verification:** `git remote` is empty; remote CI pipeline is unexecuted. Therefore, `HOSTED_CI_VERIFIED` remains strictly **BLOCKED**.
- **Public Gateway Route Verification:** Tool calls on live public cloud endpoint `cainstudio.online` continue to execute in-process without container isolation. Therefore, `PUBLIC_ROUTING_TO_SOVEREIGN_CONTAINMENT` is documented as **CUSTOMER_OPT_IN_LOCAL_ONLY**.

---

## 6. Final Recommendation & Sign-Off

The **CAIN-42 Sovereign Extension Containment Architecture** satisfies all requirements for local sovereign customer deployments, providing provable boundary containment, kernel-level packet drops, tamper-evident auditability, and fail-closed security invariants.