checkpoint: sync to 188b2eb — lenient NIP-46 payload parse, real decrypt-error logging (2026-09-16)

CHECKPOINT-encryption.md

@@ -1,3 +1,73 @@
+# Checkpoint — Amber pairing: lenient NIP-46 payload parse + real decrypt-error logging (2026-09-16)
+
+## Where things are
+- Project: `/home/avi/Projects/Keynctr`
+- Branch: `master` @ **`188b2eb`** ("fix(pairing): never reject a decrypted
+  NIP-46 payload on shape"). Previous feature HEADs: `aedde8f`, `759b5dd`,
+  `5aa122d`, `f59c2b1`.
+- Working tree: clean for tracked files. Untracked intentionally NOT
+  committed: `COSMIC_THEME.md`, `KeynectrAppIconPossibility02.jpeg`,
+  `deferred/` (stays deferred).
+- Release binary rebuilt at `188b2eb` (2026-09-16 ~21:06) — the binary the
+  Sep 15/16 Amber scans ran against was the Sep 12 build; the id-coercion +
+  payload-dump diagnostics are live NOW.
+- Verification (all green at `188b2eb`): `cargo test` **208 unit + 2 e2e
+  passed / 0 failed**, `cargo clippy --all-targets` 0 warnings,
+  `cargo fmt --check` clean, `cargo build --release` green. Frontend:
+  `npm test` **116 passed (16 files)**, `npm run typecheck` clean,
+  `npm run lint` clean, `npm run format:check` clean,
+  `npm run electron:build` and `npm run build` green.
+
+## What was completed since the last checkpoint
+- **Universal-lenient RawRequest parse (`188b2eb`)**: the derived
+  `Deserialize` (even after `aedde8f`'s params coercion) still rejected real
+  signer payloads. Replaced with a hand-written coercion deserializer: any
+  *valid JSON* deserializes — numeric/missing ids become text, object-shaped
+  `params` become a single param, a double-encoded JSON-string request is
+  unwrapped. A parse failure is now only possible for non-JSON plaintext,
+  which the log dumps verbatim. Regression tests for all five shapes.
+- **Real decrypt-error logging (`188b2eb`)**: pairing decrypt failures now
+  log the actual NIP-44 error (invalid HMAC vs invalid padding vs wrong
+  conversation key) instead of a generic "wrong conversation key", and the
+  not-a-request log prints the exact decrypted payload.
+- **Offline forensics (no commit)**: all four captured pairing frames in
+  `~/Tools/keynctr-debug/pairing-capture.jsonl` (latest: Sep 16 20:11) are
+  163-byte NIP-44 v2 payloads = 1 ver + 32 nonce + 98 buffer + 32 MAC.
+  98 is a VALID final-spec padding bucket (plaintext 65–96 bytes; the
+  observed 89 fits). So the frames are spec-conformant, decryption
+  succeeds, and the failure was purely the JSON-shape parse — confirming
+  the fix targets the right layer. Note `/tmp/keynctr-el*.log` no longer
+  exists (tmp-cleaner); backend stderr now only reaches the Electron
+  console — the next failed scan's payload dump needs
+  `npx electron .` launched from a terminal or with stderr redirected.
+
+## Commits added (newest first)
+- `188b2eb` fix(pairing): never reject a decrypted NIP-46 payload on shape
+
+## How to reproduce / exercise
+- Dev loop (unchanged): `npx vite --port 5173` in `frontend/` FIRST, then
+  `NOSTR_GUI_DEV_URL=http://localhost:5173 KEYNCTR_ENABLE_GPU=1 npx electron .`.
+  To capture pairing diagnostics: run electron with stderr kept, e.g.
+  `... npx electron . 2>&1 | tee ~/Tools/keynctr-debug/el.log`.
+- E2E: `cargo test --test nip46_e2e` (no network) — green.
+- GUI: Signer mode -> "Show QR" -> scan in Amber -> approve. Raw pairing
+  events keep appending to `~/Tools/keynctr-debug/pairing-capture.jsonl`.
+
+## Outstanding / next steps
+1. **Live Amber re-scan required** (cannot be done from an unattended run):
+   if pairing still fails, the backend log now contains the exact decrypted
+   89-byte payload and/or the exact NIP-44 error — that text names the last
+   possible cause.
+2. If the payload turns out to be valid JSON but not `method:"connect"`
+   (e.g. Amber's deferred-approval `get_public_key` first), the log will
+   show it and the handshake gate can be relaxed accordingly.
+3. `publish_profile_metadata` (kind 0) still signs locally — reroute
+   through `Signing` for external profiles (P2).
+4. Step 5 (KDF upgrade), Step 6 (undo preserves ProfileSummary), Step 7
+   (rename pass incl. `homepage` URL).
+
+---
+
 # Checkpoint — QR pairing, identity adoption, always-allow grants + pairing-relay widening (2026-09-12)
 
 ## Where things are