Commit Graph

4 Commits

Author SHA1 Message Date
Joseph Doherty 460c61df43 [R3/R4] Path-A trace: synthesizer is in Lmx.dll's NMX-frame decoder
Five-stage Ghidra headless decompile traces the byte-to-MXSTATUS_PROXY
synthesis path end-to-end across LmxProxy.dll and Lmx.dll. New evidence
files committed alongside R3/R4 verdict update:

- analysis/ghidra/exports/LmxProxy.dll.fire-event-xrefs.md
- analysis/ghidra/exports/LmxProxy.dll.status-synthesis-decompile.md
- analysis/ghidra/exports/LmxProxy.dll.mxstatus-safearray-decompile.md
- analysis/ghidra/exports/Lmx.dll.set-attribute-result-decompile.md

Layer-by-layer findings (bytes flow inward; synthesis flows outward):

1. `Lmx.aaDCT` at 0x10178fc0 is `SysAllocString(L"Lmx.aaDCT")` — a
   tracing category BSTR, not a table.
2. `MXSTATUS_PROXY` is a 16-byte marshalled struct (4 × i16 padded
   to i32 boundaries with Pack=4) — the OUTPUT of synthesis, not a
   lookup entry.
3. `LmxProxy.dll` Fire_* event handlers receive already-populated
   `MXSTATUS_PROXY[]` and forward through ATL dispatch — no synthesis.
4. `LmxProxy.dll` Fire_* CALLERS (FUN_1001657f / FUN_10016b50 /
   FUN_10016d4b) call FUN_10003f60(out_safearray, in_status_ptr,
   count=1) which is a VERBATIM memcpy of an existing 14-byte buffer
   into the SAFEARRAY — no transformation.
5. `Lmx.dll`'s `PreboundReference::OnSetAttributeResult` (FUN_10114a90)
   receives an already-populated `short *param_7` status buffer. Log
   line confirms the layout: `<success %d category %d detectedBy %d
   detail %d>`. Dispatches on typed values — synthesis is upstream of
   this function too.

The synthesizer is the NMX-frame decoder in Lmx.dll that calls
OnSetAttributeResult / OnGetAttributeResult / equivalent
OperationComplete handler. The decoder takes raw NMX bytes plus
operation context (item handle, engine state, retry state,
correlation id) and computes the populated MXSTATUS_PROXY. There is
NO static lookup table — synthesis is per-message contextual.

Two viable paths to typed promotion (both substantial; neither a
small codec patch):

- Path A: port the synthesizer. ~1-2 weeks. Requires extending the
  Rust session to track per-operation context (handles, retries,
  correlation ids). Out of V1 scope.
- Path B: empirical capture pairs. ~30 min × 6-10 scenarios. Output
  is a (byte, context → status) mapping that approximates without
  re-implementing. Risk: mapping is only valid for captured contexts.

R3/R4 stay settled at verbatim-preserve. The .NET reference does
the same for the same reason: the synthesizer is too context-
dependent to mirror without porting the entire operation-tracking
state machine.

Reopen criteria sharpened: either (a) a consumer files a concrete
use case for typed promotion of a specific byte+context combination
(Path B's empirical capture for that one combination is the cheapest
answer); or (b) a major-version bump justifies the state-machine
port (Path A).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-06 06:33:02 -04:00
Joseph Doherty 4dfc0cee65 [R3 + R4 + R8] settle protocol-level risks per Ghidra evidence
Ghidra headless decompile of `Lmx.dll`'s `aaDCT` symbol + the
`LmxProxy.dll` Fire_* event handlers (logs at
`analysis/ghidra/exports/Lmx.dll.aadct-decompile.md` and
`analysis/ghidra/exports/LmxProxy.dll.completion-status-decompile.md`)
settles **R3** and **R4** as "no static byte→status lookup table
exists":

- `Lmx.aaDCT` at `0x10178fc0` is a `SysAllocString(L"Lmx.aaDCT")` into
  a global BSTR — a logging category name, not a table.
- `MXSTATUS_PROXY` is a 4-field struct (success/category/detectedBy/
  detail), used as the marshalled COM event payload — not a static
  array of pre-mapped statuses.
- `Fire_OnDataChange` / `Fire_OnWriteComplete` / `Fire_OperationComplete` /
  `Fire_OnBufferedDataChange` (RVAs 0x15f72, 0x1611f, 0x16271, 0x163c0
  in `LmxProxy.dll`) receive ALREADY-POPULATED `MXSTATUS_PROXY[]`
  arrays — the byte-to-struct synthesis happens upstream in the
  proxy's NMX-callback ingestion code, not via a table lookup. The
  synthesis is per-event computation from operation context (engine
  ids, item handles, retry counters), not a static promotion.

R3/R4 status updated from "indefinitely deferred — no Ghidra table"
to "settled — no table exists; verbatim preservation is the canonical
answer." The .NET reference's `NmxOperationStatusMessage.TryParseInner`
+ the Rust port's `mxaccess-codec/src/operation_status.rs` already
match this canonical behaviour; no code change required.

Reopen R3/R4 only if a context-aware capture surfaces a per-byte
synthesis logic that depends on operation context — at which point
the codec would need access to the originating operation's context,
which is upstream of the bytes themselves.

**R8** marked permanently deferred — implementation already parses
NTLM AV pairs per [MS-NLMP] §2.2.2.1 (including the cross-domain
shapes `MsvAvDnsTreeName` / `MsvAvDnsComputerName` carrying the
trusted-domain DNS suffix), what's missing is the live capture, and
the live capture requires a multi-domain Windows lab not available
on this dev host. Same status pattern as F3 in `design/followups.md`.

Open evidence gaps table updated to reflect:
- Cross-domain NTLM: deferred (R8)
- Ghidra mapping table for completion-only bytes: no table exists
  (R3/R4 settled)
- Activate/Suspend transition (wire): partial (F44 + F46), live re-run
  pending (F50)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-06 06:23:05 -04:00
Joseph Doherty 808fea18a0 [F46] analysis/frida: Suspend/Activate hooks + R5 next-step
Closes the wire-side gap left by capture 077 in F44's R5 walk. The Frida
script now hooks the production LmxProxy.dll dispatchers so a future live
re-run on the AVEVA host can answer "does CLMXProxyServer issue a separate
ORPC method for Suspend/Activate, or are they synthesised client-side?"

Hooks added in `analysis/frida/mx-nmx-trace.js`:
- `LmxProxy.dll!CLMXProxyServer.Suspend`  @ RVA 0x13d9c (FUN_10013d9c)
- `LmxProxy.dll!CLMXProxyServer.Activate` @ RVA 0x14028 (FUN_10014028)

Both RVAs were extracted from
`analysis/ghidra/exports/LmxProxy.dll.string-refs.tsv` rows 119/122 (the
`CLMXProxyServer::Suspend - Server Handle` / `Activate - Server Handle`
log strings each xref one function — same pattern as the existing
AdviseSupervisory hook at 0x142b4). The hooks emit `mx.suspend.begin/end`
and `mx.activate.begin/end` events with serverHandle, itemHandle, and the
`MxStatus*` out parameter decoded as 4 x int16 (Success / Category /
DetectedBy / Detail per `src/MxNativeCodec/MxStatus.cs`). Naming matches
the F46 spec's `mx.<verb>.begin / end` grep convention rather than the
generic `call.enter / leave` shape because we want to filter these out
of large traces without false positives from other LmxProxy entrypoints.

No `Resume` / `Reactivate` exports exist in `LmxProxy.dll` — verified
against `analysis/ghidra/exports/LmxProxy.dll.ghidra.md` (no such string
xrefs) and the decompiled `ILMXProxyServer5` / `ILMXProxyServer4`
interfaces under `analysis/decompiled-mxaccess/ArchestrA/MxAccess/`
(only Suspend and Activate are declared on the dispatch interface).

The script's top-of-file comment now carries the live re-run procedure
(rebuild MxTraceHarness x86, attach Frida with `--scenario=suspend-advised`
then `--scenario=activate-advised`, save under
`captures/NNN-frida-suspend-activate-instrumented/`, grep the new TSV for
`mx.suspend.*` / `mx.activate.*` and correlate with `nmx.enter` events
in the same time window). Live capture is intentionally deferred to the
maintainer per the F46 spec — this dev box has no AVEVA install.

`design/70-risks-and-open-questions.md` R5 status updated:
- Title flag `(filed as F45)` -> `(filed as F46, hook landed pending live re-run)`
  (the docs/M6-buffered-evidence.md footnote referenced F45 from before
  F45 / F46 were de-conflicted by commit 2120dfa).
- New "Next step - F46" paragraph documents the two hooked RVAs, the
  out-param decode shape, and the verified absence of Resume / Reactivate
  symbols.
- "Current best answer" paragraph re-points the residual ORPC question
  at F46.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-06 05:42:57 -04:00
Joseph Doherty fe2a6db786 Initial project state: .NET reference, design, Rust port (M0+M1), evidence
rust / build / test / clippy / fmt (push) Has been cancelled
Layout:
- src/                    .NET 10 x64 reference: MxNativeCodec, MxNativeClient,
                          MxAsbClient, probes, tests, harnesses. Executable spec.
- design/                 Architectural plan for the Rust port (M0–M6), error
                          model, protocol invariants, risks (R1–R16), adversarial
                          review log (review.md).
- rust/                   Rust workspace. M0 skeleton + M1 codec parity.
                          mxaccess-codec: 215 unit tests + 2 cross-implementation
                          parity tests (byte-identical against .NET reference).
                          Other crates are M0 stubs awaiting M2+.
- captures/               Frida + netsh + pcap evidence per CLAUDE.md
                          ("captures are evidence, not throwaway logs").
- analysis/               Decompiled C# (frida/proxy/decompiled-*),
                          Ghidra exports for native DLLs (`exports/` only —
                          working state at `projects/` and AVEVA's input
                          binaries at `input/` are gitignored).
- docs/                   Reverse-engineering reference docs.
- tools/                  Setup-LiveProbeEnv.ps1 (Infisical credential fetcher),
                          Compute-Crc.ps1 (.NET parity helper).
- .github/workflows/      Rust CI: fmt + build + test + clippy on Windows.
- LICENSE                 MIT (Joseph Doherty, 2026).

Verified:
- cargo test --workspace → 217 passed (215 unit + 2 .NET parity), 0 failed
- cargo clippy --workspace -- -D warnings → clean
- cargo fmt --all -- --check → clean
- cargo publish --dry-run -p mxaccess-codec → packages cleanly

Excluded from history (see .gitignore):
- **/bin, **/obj, **/target — build artifacts
- analysis/ghidra/projects/ — Ghidra working state (regenerable)
- analysis/ghidra/input/ — AVEVA proprietary DLLs (vendor IP)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-05 06:21:00 -04:00