niom-turn/docs/testing_todo.md

Testing TODO (ideas)

This document collects concrete test ideas to increase safety/stability (especially under load and misbehaviour).

Stream (TCP/TLS) robustness

• Split reads: STUN header (20B) in 2 reads, body in multiple reads
• Split reads: ChannelData header (4B) and payload separated
• Mixed frames: STUN → ChannelData → STUN in a single read (and across multiple reads)
• Oversize frames:
  • STUN length > max → close connection (or drop frame, depending on policy)
  • ChannelData length > max → close connection (or drop frame)
• Garbage resync:
  • random bytes before valid STUN (already covered)
  • random bytes between valid frames

TURN flows (happy + negative)

• Negative cases per method (for UDP/TCP/TLS each):
  • without allocation → 437 Allocation Mismatch
  • without permission → 403 Peer Not Permitted
  • ChannelData without ChannelBind → drop + optional log counter
  • stale nonce → 438
  • wrong MI → 401/403 depending on policy

Auth

• TURN REST:
  • expired username → reject
  • username too far in the future (max TTL) → reject
  • wrong HMAC/base64 → reject
  • priority: “user exists in store” vs. “REST fallback”

Lifecycle

• Allocation expiry:
  • Refresh shortens/extends; min/max lifetime
  • Expiry removes allocation and ends relay task (no task leaks)
• Permission expiry:
  • peer is dropped after expiry
• Channel binding expiry:
  • return path falls back to Data Indication when the binding expires

Abuse/DoS prevention (once limits are implemented)

• Rate limit: auth failures per IP/username
• Max allocations per IP
• Max permissions/channels per allocation
• Bandwidth caps (bytes/s) per allocation
• Backpressure: writer queue full → define behaviour (drop/close)

Interop (manually reproducible, but documented)

• Browser plan:
  • trickle ICE / webrtc-internals: forced relay
  • UDP-only block: expect TCP/TLS fallback
  • turns: with self-signed vs. valid cert