trampler: hash lifecycle RE'd via live round-trip (client recomputes all 5 on save)

- All 5 walker hashes are recomputed client-side on save from the local CompartmentsDatabase + CompartmentDefinitionDto (same build => byte-identical hashes; no per-walker secret). Wiping any/all hashes loads/opens/edits fine; one in-editor save regenerates everything (+ new file UUID & UniqueId). - VERSION flag (WalkerBlueprintContainer.ValidateVersion) depends only on the structural Compartments/Connections hashes, not the Definition hashes; ERRORS is a separate structural check. Hashes = integrity/version-staleness markers, not security. Server upsert validation still untested. - Document the 5-hash table (3 top-level + 2 per-part) and offline-computability in docs/TRAMPLER.md + CLAUDE.md; include experiment artifacts + baseline.
2026-06-16 09:48:50 +02:00
parent aa7425221f
commit bd01d6753a
5 changed files with 163 additions and 6 deletions
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -37,6 +37,12 @@ The four data sources, and which tools own them:
 - IL2CPP source of truth: `il2cpp/dump.cs` (Il2CppDumper output — signatures/RVAs only, no method
  bodies). `il2cpp/`, `ghidra/`, `snapshots/`, `bundles`, `Walkers`, `reverse/.secrets/` are
  git-ignored (large/regenerable/secret). Live PlayFab token: `reverse/.secrets/playfab_token.json`.
+- **Game runtime data dir** (`%USERPROFILE%\AppData\LocalLow\Hologryph\SAND`, here
+  `/mnt/c/Users/DownloadPizza/AppData/LocalLow/Hologryph/SAND/`) holds:
+  - **`Player.log`** — Unity log; check it to see what the client did (walker file reads:
+    `[FS_STANDALONE] ReadAllFilesAsync … Path: …/Data/Walkers`; master-server handshake:
+    `[MasterServer] … Login / Connection failed to /connect`). `Player-prev.log` = previous run.
+  - **`Data/Walkers/*.wbt`** — the live walker saves (the `Walkers/` symlink points here).

 ## The `.wbt` walker save format (current focus)

@@ -71,6 +77,16 @@ offline, `build_wbt.py pack` recomputes the two Compartment* hashes and **copies
 Definition* hashes from the source — correct as long as the *set of part definitions* is unchanged;
 it raises if you add a part whose `DefinitionHash` has never been harvested.

+**Hash lifecycle (verified live 2026-06-16 — see `docs/TRAMPLER.md`):** the client **recomputes all 5
+hashes on save** from its own database (same build ⇒ byte-identical hashes; no per-walker secret —
+plain unsalted MD5, they're integrity/version-staleness markers, **not** security). Wiping any/all
+hashes is harmless: a walker with blank hashes still **loads, lists, and opens in the editor**, and
+**one in-editor save regenerates everything** (and mints a new file UUID + `UniqueId`). The `VERSION`
+flag in `Player.log`'s `CheckValidBlueprint: ERRORS {0}, VERSION:{1}` (=`WalkerBlueprintContainer
+.ValidateVersion`, which recomputes against the *current* DB/definitions) tracks only the **structural**
+hashes (Compartments/Connections); Definition hashes don't affect client validation. Server-side upsert
+validation is untested (blocked by master-server `/connect` errors during the playtest).
+
 Enum tables (from `dump.cs`): `ConnectionSlotType` 0 DOOR,1 HATCH,2 STRUCTURE,3 BALCONY,4 DECK ·
 `ConnectionState` 0 DEFAULT,1 DOOR,2 OPEN · `ConnectionsCount` 0 FULL,1 PARTIAL,2 ERROR. Note the
 master-server **WS form** serializes these as integers and omits null `EpbId`; the storage/hash form
--- a/docs/TRAMPLER.md
+++ b/docs/TRAMPLER.md
@@ -37,14 +37,68 @@ and `ConnectionDto={Id, Blueprint}`.
  `ConnectionsCount` FULL0/PARTIAL1/ERROR2.
 - Verified by a **storage→WS→storage round-trip** on the sample (byte-identical, hashes reproduce).

-## The 3 hashes  (`reverse/trampler_hashes.py`)
+## The 5 hashes  (`reverse/trampler_hashes.py`, `walker/walker_hashes.py`)
 `MD5Utility.ComputeHash(obj) = MD5( UTF8( JsonConvert.SerializeObject(obj) ) )` → **uppercase hex,
 no separators** (`X2`). Newtonsoft compact: no whitespace, PascalCase, declaration-order keys, nulls
-included, enums as **name strings**.
- **`CompartmentsHash = MD5(compact-JSON(Compartments))`** — VERIFIED.
- **`ConnectionsHash  = MD5(compact-JSON(Connections))`** — VERIFIED (this was the previously-hard #3).
- `DefinitionsHash` = MD5 of the actual `CompartmentDefinitionDto`s — PROVISIONAL (hashes the
-  definitions, not blueprint fields; verify live vs a current `GetTrampler` + `GetCompartmentDefinitions`).
+included, enums as **name strings**. A `WalkerBlueprintDto` carries **3 top-level** hashes; each
+`CompartmentBlueprintDto` (chassis + every part) carries **2 more**.
+
+| Hash | Scope | What it hashes | Offline-computable? |
+|------|-------|----------------|---------------------|
+| `CompartmentsHash` | top-level | `MD5(compact-JSON(Compartments list))` | **YES** — VERIFIED |
+| `ConnectionsHash` | top-level | `MD5(compact-JSON(Connections list))` | **YES** — VERIFIED |
+| `DefinitionsHash` | top-level | `MD5(JSON(Compartments→CompartmentDefinitionDto))` | **NO** — server-sourced |
+| `CompartmentHash` | per-part | placement fingerprint (constant per EpbId+placement) | **NO from scratch** — harvest |
+| `DefinitionHash` | per-part | `MD5(JSON(that part's CompartmentDefinitionDto))` | **NO** — server-sourced |
+
+- The two **Definition** hashes (`DefinitionsHash` + per-part `DefinitionHash`) hash the rich
+  server-side `CompartmentDefinitionDto` — which is **NOT** in the blueprint and **NOT** equal to the
+  server's `GetCompartmentDefinitions` *pricing* DTO (brute-forcing every field subset of that DTO
+  reproduced neither). They can only be **harvested** (every part placed in the in-game editor writes
+  them into the `.wbt` save) → `extracted/definition_hashes_known.json`, `walker/harvest_hashes.py`.
+- `CompartmentsHash` is a hash **over the Compartments list including each part's `CompartmentHash` +
+  `DefinitionHash` fields** — so wiping per-part Definition hashes also changes `CompartmentsHash`.
+- Per-part `CompartmentHash` is **constant per EpbId** across placements (verified across 30 harvested
+  EpbIds); per-part `DefinitionHash` is constant per EpbId **except** it varies with `DecorationsInfo`
+  content (only `walker_compDeck_Square_Open_1x1_epb` seen to differ so far).
+
+## Hash lifecycle & purpose — round-trip experiment (2026-06-16, live client)
+Test: built copies of a known walker offline with hashes wiped, loaded them in the game, watched
+`Player.log` (`CheckValidBlueprint: ERRORS {0}, VERSION:{1}, {2}` = `haveBuildingErrors`,
+`isVersionValid`, `UniqueId`), then opened/saved in the in-game editor and re-decoded.
+
+| Variant | Comp/Conn hashes | Definition hashes | `ERRORS` | `VERSION` |
+|---------|------------------|-------------------|----------|-----------|
+| Definition hashes only wiped | valid | wiped | False | **True** |
+| **all 5 wiped** | wiped | wiped | False | **False** |
+| untouched original (current build) | valid | valid | False | True |
+| genuinely old-version walker | valid | valid | False | False |
+
+Findings (data-derived):
+- **The client recomputes ALL FIVE hashes locally on save** from its own `CompartmentsDatabase` +
+  `CompartmentDefinitionDto` container. Saving an all-wiped walker produced hashes **byte-identical** to
+  the original source (same build ⇒ same hashes). So the hashes carry **no per-walker secret** and are a
+  pure function of the build.
+- **Open/edit tolerates blank hashes**: an all-wiped walker loads, lists, and opens in the editor with
+  no error; opening + closing **without saving rewrites nothing** (file stayed byte-identical). Hashes
+  are (re)written **only on save**.
+- **Every save mints a new file UUID *and* a new `UniqueId`** (observed 3×).
+- **`isVersionValid` (the `VERSION` flag) depends only on the structural hashes** (`CompartmentsHash`/
+  `ConnectionsHash`), **not** on the Definition hashes (def-only-wiped was still `VERSION:True`).
+  `haveBuildingErrors` (`ERRORS`) is a separate structural check, independent of every hash.
+
+Purpose (mechanism from `dump.cs`, not inferred): `WalkerBlueprintContainer.ValidateVersion(
+ICompartmentsDatabase, ICompartmentDefinitionDtoContainer)` sets `isVersionValid`/`haveBuildingErrors`.
+It takes the **current** database + definitions as input ⇒ the stored hashes are a **cached fingerprint
+re-checked against a fresh recompute**: when the game's part data changes across a patch, the recompute
+won't match the stored hash and the walker is flagged stale (`VERSION:False`, → migrate/re-save). They
+are **integrity / version-staleness markers, not security** — plain unsalted MD5 we reproduce offline;
+the client just regenerates them. From the *client editor's* view the **Definition** hashes appear inert
+(no effect on `ERRORS` or `VERSION`); whether the **server** validates them on upsert is still untested
+(blocked by master-server `/connect` NREs during this playtest).
+
+Practical upshot for offline editing: edit the `.wbt`, then either recompute the two structural hashes
+yourself (`walker/walker_hashes.py`, exact) or just let **one in-editor save** regenerate all five.

 ## Footprints  (`extracted/CompartmentsDatabase.json` → `compartments[].cells[]`)
 Each compartment def has `cells[] = {position{x,y,z}, sockets{dir:{slotType:…}}, volumeOccupied,
--- a/extracted/test_allhashwiped_4020ff89.wbt
+++ b/extracted/test_allhashwiped_4020ff89.wbt
--- a/extracted/test_nodefhash_6a804acb.wbt
+++ b/extracted/test_nodefhash_6a804acb.wbt
--- a/extracted/test_nodefhash_baseline.json
+++ b/extracted/test_nodefhash_baseline.json
@@ -0,0 +1,87 @@
+{
+ "note": "Baseline hash state to diff against after the game loads/re-saves the test walker. Test walker 'Scientific Sentinel' has Definition* hashes wiped to ''. Watch which fields the game fills back in.",
+ "source_01260e82_Cranky_Third": {
+  "DefinitionsHash": "A94FBF71596E2E5FC3595F38C310AB68",
+  "CompartmentsHash": "54319EC1DDFFAF5CAE17A0FA8B0D6750",
+  "ConnectionsHash": "36777484B669177C2B402DC0830EF1BD",
+  "per_part": [
+   {
+    "EpbId": "walker_compChassis_SmallLong4_Metal_2x3_epb",
+    "DefinitionHash": "64677F77ED55788CA579CDC5D5EDC53C",
+    "CompartmentHash": "D1EBE5DDB86BD898DA22A558F5199922"
+   },
+   {
+    "EpbId": "walker_compSteering_Square_Open_1x1_epb",
+    "DefinitionHash": "8AD614A669C43EC06EC49FB2C0C9F56D",
+    "CompartmentHash": "93901C77B060FA462EB1C415D7304E07"
+   },
+   {
+    "EpbId": "walker_compReactor_Round_Open_2x1_epb",
+    "DefinitionHash": "5744B05118A9CF470EEB77DC2FB8C62D",
+    "CompartmentHash": "BDADD1B66303873E30F8D031EE1F99A1"
+   },
+   {
+    "EpbId": "walker_compCaptainCrew_Wood_1x1_epb",
+    "DefinitionHash": "37F659D0A1EDBFEF11138B059BA87630",
+    "CompartmentHash": "CA0A7339EC20ADAAD07B756BA3206F77"
+   },
+   {
+    "EpbId": "walker_compDeck_Square_Open_1x1_epb",
+    "DefinitionHash": "04E304846A06AF8E3209DF1054D1E784",
+    "CompartmentHash": "0B8CC69BD1392E6EA7EA37BE5DE6C372"
+   },
+   {
+    "EpbId": "walker_compDeck_Square_Open_1x1_epb",
+    "DefinitionHash": "04E304846A06AF8E3209DF1054D1E784",
+    "CompartmentHash": "0B8CC69BD1392E6EA7EA37BE5DE6C372"
+   },
+   {
+    "EpbId": "walker_compSpecial_Entry_Frame_1x1_epb",
+    "DefinitionHash": "CB2209E5C634FBC37C242DE4ED91B70C",
+    "CompartmentHash": "9FB555D20A1BADBBD3AD73DFC989F9B6"
+   }
+  ]
+ },
+ "test_6a804acb_Scientific_Sentinel_NODEFHASH": {
+  "DefinitionsHash": "",
+  "CompartmentsHash": "B0DC03D36083E9A6A7C86DFC1E87D978",
+  "ConnectionsHash": "36777484B669177C2B402DC0830EF1BD",
+  "per_part": [
+   {
+    "EpbId": "walker_compChassis_SmallLong4_Metal_2x3_epb",
+    "DefinitionHash": "",
+    "CompartmentHash": "D1EBE5DDB86BD898DA22A558F5199922"
+   },
+   {
+    "EpbId": "walker_compSteering_Square_Open_1x1_epb",
+    "DefinitionHash": "",
+    "CompartmentHash": "93901C77B060FA462EB1C415D7304E07"
+   },
+   {
+    "EpbId": "walker_compReactor_Round_Open_2x1_epb",
+    "DefinitionHash": "",
+    "CompartmentHash": "BDADD1B66303873E30F8D031EE1F99A1"
+   },
+   {
+    "EpbId": "walker_compCaptainCrew_Wood_1x1_epb",
+    "DefinitionHash": "",
+    "CompartmentHash": "CA0A7339EC20ADAAD07B756BA3206F77"
+   },
+   {
+    "EpbId": "walker_compDeck_Square_Open_1x1_epb",
+    "DefinitionHash": "",
+    "CompartmentHash": "0B8CC69BD1392E6EA7EA37BE5DE6C372"
+   },
+   {
+    "EpbId": "walker_compDeck_Square_Open_1x1_epb",
+    "DefinitionHash": "",
+    "CompartmentHash": "0B8CC69BD1392E6EA7EA37BE5DE6C372"
+   },
+   {
+    "EpbId": "walker_compSpecial_Entry_Frame_1x1_epb",
+    "DefinitionHash": "",
+    "CompartmentHash": "9FB555D20A1BADBBD3AD73DFC989F9B6"
+   }
+  ]
+ }
+}