Files
webui/api/helpers.py
Nathan Esquenazi b8b62722ec feat: Sprint 19 — password auth, security headers, login page
Auth system (off by default, zero friction for localhost):
- New api/auth.py module: password hashing (SHA-256 + STATE_DIR salt),
  signed HMAC session cookies (24h TTL), auth middleware
- Enable via HERMES_WEBUI_PASSWORD env var or Settings panel
- Minimal dark-themed login page at /login (self-contained HTML)
- POST /api/auth/login, /api/auth/logout, GET /api/auth/status
- Settings panel: "Access Password" field + "Sign Out" button
- password_hash added to settings.json (null = auth disabled)

Security hardening:
- Security headers on all responses: X-Content-Type-Options: nosniff,
  X-Frame-Options: DENY, Referrer-Policy: same-origin
- POST body size limit: 20MB cap in read_body() to prevent DoS

Closes #23. 9 new tests. Total: 304 passed, 0 regressions.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-04-03 05:53:26 -07:00

72 lines
2.5 KiB
Python

"""
Hermes Web UI -- HTTP helper functions.
"""
import json as _json
from pathlib import Path
from api.config import IMAGE_EXTS, MD_EXTS
def require(body: dict, *fields):
"""Phase D: Validate required fields. Raises ValueError with clean message."""
missing = [f for f in fields if not body.get(f) and body.get(f) != 0]
if missing:
raise ValueError(f"Missing required field(s): {', '.join(missing)}")
def bad(handler, msg, status=400):
"""Return a clean JSON error response."""
return j(handler, {'error': msg}, status=status)
def safe_resolve(root: Path, requested: str) -> Path:
"""Resolve a relative path inside root, raising ValueError on traversal."""
resolved = (root / requested).resolve()
resolved.relative_to(root.resolve()) # raises ValueError if outside root
return resolved
def _security_headers(handler):
"""Add security headers to every response."""
handler.send_header('X-Content-Type-Options', 'nosniff')
handler.send_header('X-Frame-Options', 'DENY')
handler.send_header('Referrer-Policy', 'same-origin')
def j(handler, payload, status=200):
"""Send a JSON response."""
body = _json.dumps(payload, ensure_ascii=False, indent=2).encode('utf-8')
handler.send_response(status)
handler.send_header('Content-Type', 'application/json; charset=utf-8')
handler.send_header('Content-Length', str(len(body)))
handler.send_header('Cache-Control', 'no-store')
_security_headers(handler)
handler.end_headers()
handler.wfile.write(body)
def t(handler, payload, status=200, content_type='text/plain; charset=utf-8'):
"""Send a plain text or HTML response."""
body = payload if isinstance(payload, bytes) else str(payload).encode('utf-8')
handler.send_response(status)
handler.send_header('Content-Type', content_type)
handler.send_header('Content-Length', str(len(body)))
handler.send_header('Cache-Control', 'no-store')
_security_headers(handler)
handler.end_headers()
handler.wfile.write(body)
MAX_BODY_BYTES = 20 * 1024 * 1024 # 20MB limit for non-upload POST bodies
def read_body(handler):
"""Read and JSON-parse a POST request body (capped at 20MB)."""
length = int(handler.headers.get('Content-Length', 0))
if length > MAX_BODY_BYTES:
raise ValueError(f'Request body too large ({length} bytes, max {MAX_BODY_BYTES})')
raw = handler.rfile.read(length) if length else b'{}'
try:
return _json.loads(raw)
except Exception:
return {}