Fix Docker OpenClaw HMAC persistence and privacy-core build warnings.

Persist OPENCLAW_HMAC_SECRET to data/openclaw.env so empty Docker env vars no longer block auth after UI bootstrap. Add verify_hmac.py, silence Rust warnings (#423), and document Docker signing (#424).

Co-authored-by: Cursor <cursoragent@cursor.com>

openclaw-skills/shadowbroker/SKILL.md

@@ -88,6 +88,19 @@ For compatibility with older snippets, `SHADOWBROKER_KEY` is also accepted by
 the client as the same HMAC signing secret. Prefer `SHADOWBROKER_HMAC_SECRET`
 for new setups.
 
+**Docker Compose:** host-side agents (`localhost:8000` from the Kali/macOS host)
+are not loopback inside the backend container — HMAC is required. After
+**Connect OpenClaw → Bootstrap → Reveal**, the secret is persisted under
+`data/openclaw.env` on the `backend_data` volume. Restart the backend once,
+then verify with:
+
+```bash
+python openclaw-skills/shadowbroker/verify_hmac.py
+```
+
+Hand-rolled signers must hash the **exact** POST bytes. Use compact JSON:
+`json.dumps(payload, separators=(",", ":"), sort_keys=True)`.
+
 ### SSE Stream (Preferred — Low-Latency Push)
 
 Open the SSE stream **first** and keep it open for the session.  The server pushes

openclaw-skills/shadowbroker/verify_hmac.py

@@ -0,0 +1,81 @@
+#!/usr/bin/env python3
+"""Verify OpenClaw HMAC auth against a running ShadowBroker backend.
+
+Usage:
+    export SHADOWBROKER_URL=http://127.0.0.1:8000
+    export SHADOWBROKER_HMAC_SECRET=<from Connect OpenClaw modal>
+    python verify_hmac.py
+
+Signs the same canonical JSON body as openclaw-skills/shadowbroker/sb_query.py.
+"""
+
+from __future__ import annotations
+
+import hashlib
+import hmac
+import json
+import os
+import secrets
+import sys
+import time
+import urllib.error
+import urllib.request
+
+
+def sign(method: str, path: str, body: bytes, secret: str) -> dict[str, str]:
+    ts = str(int(time.time()))
+    nonce = secrets.token_hex(16)
+    digest = hashlib.sha256(body).hexdigest()
+    message = f"{method.upper()}|{path}|{ts}|{nonce}|{digest}"
+    signature = hmac.new(secret.encode(), message.encode(), hashlib.sha256).hexdigest()
+    return {
+        "X-SB-Timestamp": ts,
+        "X-SB-Nonce": nonce,
+        "X-SB-Signature": signature,
+        "Content-Type": "application/json",
+    }
+
+
+def main() -> int:
+    base = os.environ.get("SHADOWBROKER_URL", "http://127.0.0.1:8000").rstrip("/")
+    secret = os.environ.get("SHADOWBROKER_HMAC_SECRET", "").strip()
+    if not secret:
+        print("Set SHADOWBROKER_HMAC_SECRET to the value from Connect OpenClaw.", file=sys.stderr)
+        return 2
+
+    path = "/api/ai/channel/command"
+    payload = {"cmd": "channel_status", "args": {}}
+    body = json.dumps(payload, separators=(",", ":"), sort_keys=True).encode("utf-8")
+    headers = sign("POST", path, body, secret)
+    req = urllib.request.Request(
+        f"{base}{path}",
+        data=body,
+        headers=headers,
+        method="POST",
+    )
+
+    try:
+        with urllib.request.urlopen(req, timeout=15) as resp:
+            text = resp.read().decode("utf-8", errors="replace")
+            print(f"HTTP {resp.status}")
+            print(text)
+            return 0
+    except urllib.error.HTTPError as exc:
+        detail = exc.read().decode("utf-8", errors="replace")
+        print(f"HTTP {exc.code}")
+        print(detail)
+        if exc.code == 403:
+            print(
+                "\nTips:\n"
+                "- Bootstrap + Reveal the HMAC secret in AI Intel → Connect OpenClaw\n"
+                "- Use the exact secret (no extra whitespace)\n"
+                "- Sign compact JSON: json.dumps(..., separators=(',', ':'), sort_keys=True)\n"
+                "- Hit the backend port directly (e.g. :8000), not the Next.js :3000 proxy\n"
+                "- After upgrading, restart the backend so data/openclaw.env is loaded",
+                file=sys.stderr,
+            )
+        return 1
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())