Files
mxaccess/design
Joseph Doherty ed17c07c10 [M5] mxaccess-asb-nettcp: M5 plan + F19 deps + F23 auth crypto port
F18 plans M5 as 9 sub-followups (F18-F26 + F27 constant-time DH) per
design/dependencies.md:73-89. Wave-1 streams F20-F23+F24 are parallel-safe
after F19 (workspace deps). F25 (ASB client) is sequential after the
framing/encoder streams. F26 (Session over AsbTransport) is sequential
after F25.

F19 — workspace deps for the M5 crypto + framing surface: hmac, md-5,
sha1, sha2, aes, cbc, pbkdf2, flate2, rand, num-bigint, num-traits,
num-integer, quick-xml, tokio-util, zeroize. Pinned to the digest 0.10 /
cipher 0.4 generation matching mxaccess-rpc.

F23 — ports `AsbSystemAuthenticator.cs` (167 LoC) to
`mxaccess-asb-nettcp::auth`. Wire-byte parity points: .NET BigInteger
little-endian two's-complement byte order with optional 0x00 sign-byte
suffix; AES-128-CBC with PKCS7 padding; PBKDF2-SHA1 1000 iterations
over `Convert.ToBase64String(crypto_key)` with ASCII salt
"ArchestrAService"; deflate-then-AES (Baktun) vs raw-AES (Apollo)
selected by `:V2` lifetime suffix; HMAC-MD5/SHA1/SHA512 negotiated per
`AsbSolutionCryptoParameters.HashAlgorithm` (with `force_hmac=true`
fallback to HMAC-SHA1 for unrecognised algorithms).

13 unit tests cover the cryptographic primitives + DH peer agreement +
.NET byte-order round-trip + Apollo lifetime dispatch.

F27 — filed for the `num-bigint` → `crypto-bigint::BoxedUint` swap once
the latter exposes a stable heap-allocated `pow_mod`. Currently at
parity with the .NET reference (also not constant-time).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-05 10:36:15 -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).