Harden security item 2: KDF policy, export safeguards, and tests

memory-update.md

@@ -1,76 +1,35 @@
-# Learnings from known-issues-agent run
+# Memory Update (2026-02-25)
 
-- Initialized `KNOWN_ISSUES.md` as it was missing.
-- Verified that `npm run --prefix torch lint` requires `npm install --prefix torch` to be run first.
-- Confirmed that `landing/index.html` no longer contains `innerHTML` violations.
-- Confirmed `torch-config.json` correctly defines scheduler handoff commands.
-- Consolidated resolved issues into `KNOWN_ISSUES.md` for historical tracking.
+## Security Item 2 Progress
+- Raised PBKDF2 default policy for new profiles from `50_000` to `200_000` via `ConfigManager.DEFAULT_PBKDF2_ITERATIONS`.
+- Added policy-floor enforcement in `PasswordManager._get_kdf_iterations()` so downgraded configured values are ignored during normal seed-key derivation.
+- Kept unlock backward compatibility for legacy profiles by preserving fallback attempts for `50_000` and `100_000` iterations.
 
-# Learnings from test-coverage run
+## KDF Metadata Consistency
+- Added `PasswordManager._build_seed_kdf_config(...)` and wired all seed re-encryption callsites to persist explicit KDF metadata (`pbkdf2` or `argon2id`) matching active derivation policy.
 
-- `artifacts/coverage/coverage.full.json` is useful for choosing high-impact gaps quickly; `src/utils/input_utils.py` was at 25.00% and had no direct tests.
-- Added deterministic unit tests for `timed_input` POSIX/Windows dispatch, timeout handling, and backspace behavior without relying on real terminal input.
-- Added positive-path tests for `utils/terminal_utils` header/notification rendering to complement existing failure-path tests.
-- Focused coverage after changes: `src/utils/input_utils.py` reached 100% and `src/utils/terminal_utils.py` reached 88% in targeted runs.
+## Plaintext Export Safeguard
+- Hardened `handle_export_database` interactive flow: plaintext export now requires explicit warning + second confirmation.
+- Added audit metadata for backup exports (`encryption_mode` field).
 
-# Learnings from entry-type verification run
+## Nonce Lifecycle Decision
+- Removed CRC32 nonce tracking from `EncryptionManager.encrypt_data`.
+- Policy now relies on fresh random 96-bit AES-GCM nonces per encryption call to avoid CRC false positives and in-memory collision bookkeeping.
 
-- Added an enum-driven regression suite to verify every `EntryType` value can be added, retrieved, and filtered via `EntryManager`.
-- Guard test now asserts `ALL_ENTRY_TYPES` stays in sync with the `EntryType` enum, so introducing a new kind requires explicit test coverage updates.
+## Added/Updated Tests
+- Expanded `src/tests/test_kdf_modes.py` with negatives for:
+  - wrong Argon2 params on unlock,
+  - tampered KDF wrapper payload,
+  - downgraded KDF policy attempt (floor enforcement).
+- Added `src/tests/test_export_plaintext_policy.py` for double-confirm plaintext export guard.
+- Updated expectations in `test_config_manager.py` and `test_kdf_strength_slider.py` for new PBKDF2 baseline.
 
-# Learnings from account roundtrip restore run
-
-- Added end-to-end regression tests for account lifecycle recovery:
-  Nostr sync -> local account deletion -> seed-based restore -> entry integrity checks.
-- Added parallel lifecycle regression for portable backups:
-  export -> local account deletion -> import with seed -> entry integrity checks.
-- `PasswordManager` test harnesses that call `sync_vault()` need `state_manager` set (even `None`) to avoid `AttributeError` in `sync_vault_async`.
-
-# Learnings from real-relay roundtrip run
-
-- Added an opt-in `@pytest.mark.network` roundtrip test in `test_nostr_real.py` that uses live relays and validates sync -> delete local index -> seed-based restore.
-- Real-relay tests should isolate keyspace per run using a random `account_index` so snapshot queries do not collide with prior runs.
-- Relay propagation can be eventual; bounded retry/backoff around `attempt_initial_sync()` improves stability for live network execution.
-
-# Learnings from live relay + portable chain run
-
-- Added an opt-in live test that chains both recovery paths: real-relay sync and portable export/import, then re-syncs and restores again from relays.
-- Keeping `fingerprint` + `account_index` consistent across source/import/restore clients preserves deterministic relay identity for end-to-end verification.
-
-# Learnings from nostr-index-size gating update
-
-- `test_nostr_index_size_limits` remains discoverable in test collection but now requires explicit `NOSTR_INDEX_SIZE_E2E=1` to execute.
-- This avoids automatic execution in CI desktop jobs while preserving manual E2E stress capability.
-
-# Learnings from 1000-entry live index-size run
-
-- With `NOSTR_INDEX_SIZE_E2E=1`, live relays handled checkpoints up to 1000 entries with successful publish/retrieve at every batch.
-- Observed encrypted payload growth is strongly superlinear (about 30 KB at 100 entries to about 4.6 MB at 1000 entries), which is useful for practical relay size planning.
-
-# Learnings from security checklist + threat model kickoff
-
-- Added `docs/security_readiness_checklist.md` with status/owner/evidence fields and explicit exit criteria per security readiness item.
-- Started item 1 by drafting `docs/threat_model.md` with scope, assets, trust boundaries, attacker profiles, assumptions, non-goals, and prioritized risks.
-- Added five explicit decision gates to complete item 1 (metadata leakage posture, endpoint stance, recovery policy, relay trust posture, release trust chain).
-
-# Learnings from threat model defaults pass
-
-- Added concrete proposed defaults and requirements for all five item-1 decision gates in `docs/threat_model.md`.
-- Added a decision approval table so maintainers can formally approve/reject each gate and close item 1 with traceable signoff.
-
-# Learnings from threat model provisional approval
-
-- Applied best-judgment provisional approvals for all five decision gates and recorded them in `docs/threat_model.md`.
-- Marked checklist item 1 as `Done` in `docs/security_readiness_checklist.md` with evidence and approval date.
-
-# Learnings from crypto/key-management review kickoff
-
-- Added `docs/crypto_key_management_review.md` and moved checklist item 2 to `In Progress`.
-- Identified immediate P0 gaps: PBKDF2 baseline appears low for modern threat levels and Argon2 `time_cost` config is not clearly wired through all active unlock paths.
-- Documented prioritized remediation plan and explicit completion criteria for closing item 2.
-
-# Learnings from argon2 wiring remediation
-
-- Added `PasswordManager._derive_seed_key` and related config helpers so seed-key derivation consistently applies configured `kdf_mode` and Argon2 `time_cost`.
-- Replaced multiple direct seed-key derivation callsites with the shared helper across setup/unlock/import/password-change flows.
-- Added focused tests in `src/tests/test_kdf_modes.py` validating Argon2 `time_cost` propagation and PBKDF2 iteration override behavior.
+## Validation
+- Ran targeted suite:
+  - `src/tests/test_kdf_modes.py`
+  - `src/tests/test_export_plaintext_policy.py`
+  - `src/tests/test_config_manager.py`
+  - `src/tests/test_kdf_strength_slider.py`
+  - `src/tests/test_noninteractive_init_unlock.py`
+  - `src/tests/test_password_unlock_after_change.py`
+- Result: `28 passed`.