First live-test cycle against AVEVA on this box. Comparing the .NET
probe's `--dump-messages` XML output against our NBFX-encoded
envelope surfaced six structural bugs in the F25 envelope/operations
layer. All fixed; tests passing (702 workspace).
Fixes (all backed by the .NET dump as ground truth):
1. **`mustUnderstand` attribute name** — NBFS dict id was 116
(`MustUnderstand`, capital-M, a different SOAP token); SOAP 1.2
spec uses lowercase `mustUnderstand` at id 0. Sending the wrong
one triggered a WCF parse fault that surfaced as TCP RST.
2. **Missing `<a:MessageID>` header** — WCF's default binding
requires MessageID for two-way operations. We now auto-generate
`urn:uuid:<v4>` per envelope via a small inline `make_random_uuid_v4`
helper (no `uuid` crate dep).
3. **Missing `<a:ReplyTo>` anonymous header** — WCF's
BinaryMessageEncoder always emits `<a:ReplyTo><a:Address>...
addressing/anonymous</a:Address></a:ReplyTo>` for two-way ops.
4. **ConnectionValidator field names + namespace** — we were
emitting PascalCase `<ConnectionId>` etc. .NET's WCF
DataContractSerializer uses the private backing-field names
(`<connectionIdField xmlns="...ASBContract">guid</connectionIdField>`)
per `[DataMember(Name = "fooField")]`. Added the
`xmlns:i="...XMLSchema-instance"` declaration WCF emits
alongside (even when no `i:nil` is used). Decoder now accepts
both PascalCase (legacy tests) and DataContract field names.
5. **`<ASBIData>` over-wrapping** — we were emitting
`<Items><ASBIData>{bytes}</ASBIData></Items>`. .NET's
`AsbDataCustomSerializer.WriteStartObject` (`AsbContracts.cs:
1561-1572`) REPLACES the field's outer element with `<ASBIData>`
directly — there's no `<Items>` wrapper on the wire. Fixed by
collapsing `BodyField::AsbiDataElement` to emit just `<ASBIData>`
without the named outer element. The `name` field is retained
for self-documentation.
6. **`collect_asbidata_payloads` API** — was keyed by field name
(`Status` / `Values`); now positional (`payloads[0]`,
`payloads.get(1)`) since the wrapper element is gone. All seven
response decoders updated.
Plus tooling for the live-probe loop:
* `tools/Get-AsbPassphrase.ps1` — DPAPI loader that auto-discovers
the solution name + reads the sharedsecret + decrypts it. Sets
$env:MX_ASB_PASSPHRASE / MX_ASB_HOST / MX_ASB_VIA / MX_LIVE.
Lowercase via-host (WCF SMSvcHost is case-sensitive on the URL
host segment).
* `examples/asb-preamble-probe.rs` — diagnostic that connects,
runs the preamble, captures the PreambleAck, then sends a
synthetic ConnectRequest and dumps both directions as hex. Used
to bisect the wire-byte deltas above.
* `examples/asb-subscribe.rs` port default fixed (5074 → 808 —
WCF's NetTcpPortSharing/SMSvcHost listener confirmed via
Get-NetTCPConnection).
**Status**: preamble + PreambleAck round-trip works end-to-end
against the live AVEVA install (verified via probe). The
post-preamble Connect SOAP envelope still gets TCP RST'd — the six
structural fixes above are necessary but not yet sufficient. Next
iteration needs binary wire capture (Wireshark + Npcap loopback,
or a TCP-relay middleman) to compare the .NET probe's BinaryMessageEncoder
output byte-for-byte with ours and find the remaining delta(s).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Joseph Doherty
3b09297b27