Audit pass with the threats that actually apply to a self-hosted, account-less
app: getting the Ollama key throttled or banned, and someone grinding the app
down. Per-route windows already existed; these are the missing layers.
- lib/model-guard.ts: every route that spends a model call now takes a slot —
60 calls per window across all clients (RATE_LIMIT_MODEL_TOTAL), 3 in flight
per IP, 6 in total — and the slot is released when the call finishes, on
errors and on client disconnects. Over the concurrency cap answers 429
kind=busy, not a punishment. Slots are taken after every cheap rejection so
a malformed request cannot hold one (found by the new suite: early 400s
were leaking slots).
- Images must be base64 data URLs (dataUrlSchema in lib/schemas): a plain URL
in an images field made Ollama fetch an arbitrary address on our behalf.
- Push endpoints must be a real push service (PUSH_ALLOWED_HOSTS, defaulting
to FCM/Mozilla/Apple/WNS): the server POSTs to whatever is stored.
- The rate-limit identity is the LAST x-forwarded-for hop. Reading the first
let a client spoof its own IP and dodge every per-IP limit.
- Disk guards: reports.jsonl stops at REPORTS_MAX_BYTES (8 MB), reminder
devices cap at PUSH_MAX_SUBSCRIPTIONS (50).
- Security headers: frame-ancestors 'none' + X-Frame-Options DENY, nosniff, a
referrer policy and a Permissions-Policy without camera/mic/geo/payment.
New tests/security-test.mjs (13 checks, registered in run-all) proves each
guard against a slow stub Ollama with deliberately tiny limits. README:
security notes + rate-limit tables updated. Version 0.1.3, SW -> v51.
Check my work (third homework mode)
- One model call with its own system prompt marks the student's own
attempt: verdict, what's right, each issue with why + fix, and the
corrected version that keeps everything the student got right.
Unasked-for extras are never errors. The attempt is typed/pasted
(photos of handwriting are documented as unsupported) and stored in
the record so Redo re-checks the same work.
- Server: mode "check" + solution on POST /api/homework (zod, 400
server.needSolution without one) and the same NDJSON stream; new
checkHomework() pipeline with repair-once validation.
Follow-ups
- New POST /api/homework/refine (plain JSON, RATE_LIMIT_REFINE, zod,
auth before body): shorter / more detail / explain, plain text back,
language preserved.
- Shorter + More detail + Original rewrite the finished answer and the
corrected version in place (FollowUpBar); every guide step has
Explain step N differently; failed calls say so without losing text.
Turn into a study deck
- Any result hands its content (answer, corrected version or assembled
guide) to New deck through a one-shot sessionStorage seed with the
options step pre-filled.
UI
- Phone step 2 gains the third card: tapping it reveals the solution
field + submit; desktop has three cards and the solution field shows
with the mode. Homework history labels and share/card previews cover
the new mode.
Verified: new phase-3 suite 20/20 against a stub Ollama (check payload,
missing-solution 400, refine validation, phone + desktop check flows,
shorter follow-up with restore, guide explain, deck hand-off) plus
regression 74/74, mobile 52/52, declutter 116/116, wizard 80/80,
animation 8/8, native 35/35, phase1 38/38, phase2 43/43, i18n 25/25.
Key parity 734/734. Lint + build clean. SW freezmo-v27.
