Files
mxaccess/design
Joseph Doherty daa4ea3f16
rust / build / test / clippy / fmt (push) Has been cancelled
[F12] mxaccess-nmx: NmxClient::create — auto-resolving COM-activation factory
New constructor NmxClient::create(ntlm_factory) gated on
cfg(all(windows, feature = "windows-com")). New crate feature
mxaccess-nmx/windows-com propagates to mxaccess-rpc/windows-com.
Mirrors ManagedNmxService2Client.Create() (cs:30-64) plus
ResolveService (cs:491-523).

Six-step bring-up:
  1. com_objref_provider::marshal_activated_iunknown_objref(
       "NmxSvc.NmxService", MarshalContext::DifferentMachine)
     activates and emits the OBJREF.
  2. ComObjRef::parse extracts oxid + the activated server's IUnknown
     IPID.
  3. resolve_oxid_with_managed_ntlm_packet_integrity against
     127.0.0.1:135 (RPCSS endpoint mapper) returns the server's
     (host, port) bindings + IRemUnknown IPID.
  4. parse_bracketed_host_port pulls the host + port out of the
     ncacn_ip_tcp binding's `host[port]` text. Uses rfind for the
     rightmost brackets so FQDN forms (foo.example.com[1234])
     round-trip — matches the .NET ParseBracketedHost/Port shape at
     cs:540-561.
  5. A fresh DceRpcTcpClient binds to IRemUnknown and calls
     RemQueryInterface(iunknown_ipid, INmxService2_IID,
                        fresh_causality_id, public_refs=5).
  6. A second fresh transport binds to INmxService2 via Self::connect.

The ntlm_factory: impl FnMut() -> NtlmClientContext closure is
invoked three times (one per bind); each NtlmClientContext is
consumed by its bind, so the factory must produce fresh contexts.

New NmxClientError variants:
  - Activation(ProviderError) — only emitted with windows-com on.
  - EndpointResolution { reason } — covers no ncacn_ip_tcp binding,
    malformed host[port], non-zero RemQueryInterface HRESULT.

6 offline tests on parse_bracketed_host_port: FQDN host extraction,
rfind for rightmost brackets, rejection of missing '[' / missing
']' / non-numeric port / port overflow.

1 live test (#[ignore], gated on MX_LIVE + MX_TEST_USER /
MX_TEST_PASSWORD / MX_TEST_DOMAIN populated by
tools/Setup-LiveProbeEnv.ps1): round-trips the full chain against
the AVEVA install on this host. Resolved INmxService2 IPID is
non-zero — verified end-to-end.

Workspace: mxaccess-nmx 17 → 23 (+6). All other crates unchanged.

Closes F12 in design/followups.md. F6 (ComObjRefProvider port) was
the prior blocker; with both landed, the COM-activation path is
end-to-end functional.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-05 22:21:49 -04:00
..

design/ — Rust port architectural plan

This folder is the design contract for the Rust replacement of AVEVA/Wonderware MXAccess. It is the gap between the .NET reference in src/ and the Rust crates that will be written under a sibling rust/ workspace (per CLAUDE.md).

The folder is structured as a small set of focused documents. Read in order; each builds on the previous.

File Purpose
00-overview.md Mission, two-layer goal, architectural principles, non-goals
10-raw-layer.md Byte-accurate raw MXAccess layer (codec + transport + session)
20-async-layer.md Idiomatic Tokio async layer on top of the raw layer
30-crate-topology.md Cargo workspace, crates, dependencies, build/test commands
40-protocol-invariants.md Bill of materials: IIDs, opnums, envelope/handle bytes
50-error-model.md MxStatus, error types, panic/cancellation policy
60-roadmap.md Milestones M0..M6, validation strategy
70-risks-and-open-questions.md Parity gaps, unproven flows, cross-platform constraints
dependencies.md Cross- and within-milestone parallelism map; agent budget per phase
review.md Adversarial review log (BLOCKER/MAJOR/MINOR/NIT findings, all resolved)
prompt.md /loop driver prompt for autonomous M2M6 execution
followups.md Open / resolved deferred work items; auto-triaged by prompt.md Step 0 (created on first /loop run if missing)

The design is grounded in the .NET reference at src/ and the protocol artifacts in docs/, analysis/, and captures/. Do not introduce protocol behavior in these documents that is not already proven in the reference. When adding a new claim about wire format, cite either:

  • a .cs file path in src/MxNativeCodec/, src/MxNativeClient/, or src/MxAsbClient/, or
  • a docs/*.md spec file, or
  • a captures/0NN-frida-* directory or analysis/frida/*.tsv row.

This folder is documentation, not code. When the Rust workspace is created, the design here is the contract it must satisfy. When evidence in captures/ invalidates a design decision here, update the design first, then the code.

Reading order

  • New contributor: 00 → 30 → 10 → 40 → 20 → 50 → 60 → 70.
  • Protocol question: 40 first, then the relevant section of 10.
  • API question: 20 first, then 50.
  • Planning a milestone: 60 first, cross-reference 70 for blockers.
  • Scheduling concurrent work: dependencies.md for the per-phase parallelism map.
  • Driving M2M6 autonomously via /loop: prompt.md (and the followups.md triage log it maintains).