AI_template/docs/backend/security.md

Backend: Security (Template)

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Last Updated: 2025-01-17
Phase: Phase 0 (Planning)
Status: Draft — finalize in Phase 1
Owner: Backend Architect, Security
References:

• /docs/backend/architecture.md
• /docs/backend/payment-flow.md
• /docs/backend/api-design.md

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1. Goals

• Protect sensitive data and ensure tenant isolation.
• Secure integrations (webhooks/OAuth) and billing.
• Maintain auditability for all automated and manual actions.

2. Authentication & Authorization

• Use managed auth (Clerk/Auth.js or equivalent) with secure sessions/tokens.
• Enforce tenant-scoped RBAC; validate tenant context on every request.
• Rate limit auth endpoints; protect refresh flows.

3. Data Protection

• TLS everywhere; secure headers.
• Least-privilege DB roles; encrypt secrets at rest; rotate keys.
• Avoid logging sensitive payloads (bank data, webhook bodies, LLM prompts/responses beyond trace references).
• Store reasoning_trace JSONB with care; avoid PII in traces.

4. Integrations & Webhooks

• Verify signatures for all inbound webhooks (external providers, payment provider); reject invalid; log with trace IDs.
• Idempotent processing with event ID dedupe; dead-letter queue for failures.
• Expose webhook URLs only over HTTPS; regenerate secrets on rotation.

5. Payments (provider‑agnostic)

• Use provider‑hosted Checkout/Portal; never handle raw card data.
• Store minimal billing identifiers (customer/subscription IDs, status, timestamps, plan/price).
• Enforce access based on subscription state; deny actions when inactive.

6. LLM Safety

• All LLM calls go through a single helper; centralize redaction, logging, and parameter control.
• Strip/obfuscate sensitive fields before sending to LLM; log only references in traces.

7. Audit & Events

• Log domain events to EventLog with source_agent; include user ID, tenant, timestamps, and relevant context.
• Provide read-only /api/events with pagination and filtering; protect by tenant/role.

8. Common Controls

• OWASP Top 10 coverage (SQLi, XSS, CSRF, IDOR, SSRF, etc.).
• Input validation on all external inputs; use allowlists for redirects/URLs.
• Backup/restore plan and monitoring/alerting for infra and queues.