Live-bring-up reconciliation against AVEVA's MxDataProvider on Windows.
Connect now completes end-to-end (real DH key exchange, apollo:V2
encryption, ServicePublicKey/ServiceAuthenticationData populated). Five
fixes land:
1. NBFX `PrefixElement_a..z` (0x5E-0x77) and `PrefixAttribute_a..z`
(0x26-0x3F) decode + encode arms. The server's ConnectResponse hit
`0x65 = PrefixElement_h` for a dynamically-named element and our
decoder bailed with `unknown NBFX record byte 0x65`. Both directions
now round-trip; encoder picks short-form when prefix is a single
lowercase ASCII letter.
2. xmlns redeclaration on `<Data>` AND `<InitializationVector>` inside
`AuthenticationData` / `PublicKey`. `[XmlType(Namespace = ...)]` on
AuthenticationData / PublicKey (`AsbContracts.cs:350-381`) means
XmlSerializer emits `xmlns="..."` on each direct child. The default-
ns scope ends at `</Data>`, so `<InitializationVector>` needs its own
redeclaration to stay in the data namespace; without it the server
fell back to messages-namespace and the deserialiser threw an
`InternalServiceFault`.
3. SOAP-fault detection in `AsbClient::send_envelope`. New
`ClientError::SoapFault { action, code, reason }` surfaces when the
response Action header matches the canonical `dispatcher/fault`
template; previously body decoders blindly ran and surfaced
`MissingField { field: "Status" }` masking the actual fault. Reason
text is extracted as the longest `NbfxText::Chars` in the body —
robust against the `nbfs.rs` static-dictionary id mismatches.
4. Identified blocker (filed as F28): signed-request HMAC currently
covers the NBFX wire bytes, but .NET's `AsbSystemAuthenticator.Sign`
HMACs `Encoding.UTF8.GetBytes(request.ToXml())` — the canonical XML
serialisation via `XmlSerializer` with namespace
`urn:invensys.schemas` (`AsbSerialization.cs:12-48`). Until the Rust
port emits identical XML bytes for `ConnectedRequest` subclasses,
AuthenticateMe / RegisterItems / every signed RPC fault on the
server. Connect itself is unsigned (`ServiceMessage` not
`ConnectedRequest`) which is why it works today.
5. Identified `nbfs.rs` static-dictionary id drift (filed as F29): wire
uses Fault=134/Code=142/Reason=144/Text=146/Value=154/Subcode=156
but our table has them at 114/122/124/126/134/136. Off by 20 from
id 114+ — 10 missing entries between `s` (id 112) and `Fault`. No
request-side impact (we only encode IDs ≤44, all correct); the SOAP
fault decode walks text records directly so it sidesteps the issue.
Workspace: 702 tests pass (no test count delta — wire-only fixes).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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 M2–M6 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
.csfile path insrc/MxNativeCodec/,src/MxNativeClient/, orsrc/MxAsbClient/, or - a
docs/*.mdspec file, or - a
captures/0NN-frida-*directory oranalysis/frida/*.tsvrow.
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.mdfor the per-phase parallelism map. - Driving M2–M6 autonomously via
/loop:prompt.md(and thefollowups.mdtriage log it maintains).