Initial project state: .NET reference, design, Rust port (M0+M1), evidence

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>

rust/crates/mxaccess-codec/src/lib.rs

@@ -0,0 +1,92 @@
+//! `mxaccess-codec` — pure protocol codec for the AVEVA / Wonderware MXAccess
+//! wire format. No I/O.
+//!
+//! M1 codec parity in progress. Implemented:
+//! - Foundational types: `MxReferenceHandle` (CRC-16/IBM), `NmxTransferEnvelope`
+//!   (with `reserved6_10` preservation), `MxStatus` + `MxStatusCategory` +
+//!   `MxStatusSource` + `detail_text`, `MxValue` + `MxValueKind` + `MxDataType`.
+//! - Message-body codecs: `NmxItemControlMessage` (advise/supervisory/unadvise),
+//!   `write_message` module (scalar + array, normal + timestamped Write),
+//!   `subscription_message` (DataUpdate `0x33` + SubscriptionStatus `0x32`),
+//!   `NmxReferenceRegistrationMessage` + Result, `NmxOperationStatusMessage`
+//!   (incl. the proven `00 00 50 80 00` 5-byte completion frame and the
+//!   `0x00`/`0x41`/`0xEF` 1-byte completion frames preserved verbatim),
+//!   `NmxMetadataQueryMessage` (observed pre-advise template),
+//!   `NmxTransferEnvelopeTemplate` (round-trip preserver).
+//!
+//! Remaining (wave 2): `NmxSecuredWrite2Message` (`0x38`),
+//! `ObservedWriteBodyTemplate`. ASB Variant + AsbStatus + RuntimeValue land
+//! in M5.
+//!
+//! Every wire shape here is grounded in `src/MxNativeCodec/*.cs` (the .NET
+//! reference) and `captures/0NN-frida-*` (Frida ground truth).
+
+#![forbid(unsafe_code)]
+
+pub mod envelope;
+pub mod envelope_template;
+pub mod error;
+pub mod item_control;
+pub mod metadata_query;
+pub mod observed_frame;
+pub mod observed_write_template;
+pub mod operation_status;
+pub mod reference_handle;
+pub mod reference_registration;
+pub mod secured_write;
+pub mod status;
+pub mod subscription_message;
+pub mod value;
+pub mod write_message;
+
+pub use envelope::{ENVELOPE_HEADER_LEN, NmxTransferEnvelope, NmxTransferMessageKind};
+pub use envelope_template::NmxTransferEnvelopeTemplate;
+pub use error::CodecError;
+pub use item_control::{NmxItemControlCommand, NmxItemControlMessage};
+pub use metadata_query::NmxMetadataQueryMessage;
+pub use observed_frame::{NmxObservedEnvelope, NmxObservedMessage, NmxObservedString};
+pub use observed_write_template::ObservedWriteBodyTemplate;
+pub use operation_status::{NmxOperationStatusFormat, NmxOperationStatusMessage};
+pub use reference_handle::{MxReferenceHandle, compute_name_signature, update_crc16_ibm};
+pub use reference_registration::{
+    NmxReferenceRegistrationMessage, NmxReferenceRegistrationResultMessage,
+};
+pub use secured_write::DecodedSecuredWrite;
+pub use status::{MxStatus, MxStatusCategory, MxStatusSource, detail_text};
+pub use subscription_message::{NmxSubscriptionMessage, NmxSubscriptionRecord};
+pub use value::{MxDataType, MxValue, MxValueKind};
+
+// `NmxWriteMessage` and `NmxSecuredWrite2Message` are not single struct types
+// in the Rust port — encoding/decoding live as functions in the
+// `write_message` and `secured_write` modules. Keep stubs as short type
+// aliases so existing references compile; consumers should call the module
+// functions directly.
+
+#[derive(Debug, Clone)]
+pub struct NmxWriteMessage;
+
+#[derive(Debug, Clone)]
+pub struct NmxSecuredWrite2Message;
+
+// ---- ASB types (M5 follow-up) --------------------------------------------
+
+#[derive(Debug, Clone)]
+pub struct AsbVariant;
+
+#[derive(Debug, Clone, Copy, Default)]
+pub struct AsbStatus;
+
+#[derive(Debug, Clone)]
+pub struct RuntimeValue;
+
+// ---- Convenience prelude -------------------------------------------------
+
+pub mod prelude {
+    pub use super::{
+        CodecError, MxDataType, MxReferenceHandle, MxStatus, MxStatusCategory, MxStatusSource,
+        MxValue, MxValueKind, NmxItemControlCommand, NmxItemControlMessage,
+        NmxOperationStatusMessage, NmxReferenceRegistrationMessage,
+        NmxReferenceRegistrationResultMessage, NmxSubscriptionMessage, NmxTransferEnvelope,
+        NmxTransferEnvelopeTemplate, NmxTransferMessageKind,
+    };
+}