Live investigation (direct from a VPN host to the 2023 R2 historian's real WCF
port) showed the certificate transport + NegotiateAuthentication auth work
cross-platform, and that the event-read chain needs the 0x501 event connection
mode for CM_EVENT RegisterTags to succeed (0x402/0x401 fail). Even with
registration succeeding over a window that has events, StartEventQuery returns a
0-row header and long-polls — the same server-side per-connection row gate proven
for gRPC. Adds: EventReadConnectionModeOverride (diagnostic), and spike knobs —
cross-platform cert gate, version-check bypass, per-call timeout, overall budget
with phase-diagnostic dump, connection-mode override.
Claude-Session: https://claude.ai/code/session_012SDSQ3AcaXqPcBtDESBRii
When the historian is reached through a port-forward whose local port differs
from the server's real service port, WCF's server-side AddressFilter rejects the
message (To = tunnel port != server port). ConnectViaAddress lets the channel
connect to the tunnel while addressing the SOAP To the real Host/Port endpoint.
Applied in HistorianWcfClientCredentialsHelper.Configure (the critical event
factories already call it). The C2 spike reads HISTORIAN_WCF_EVENT_VIA.
Claude-Session: https://claude.ai/code/session_012SDSQ3AcaXqPcBtDESBRii
Turns the previously-discarded GetInterfaceVersion result into a connect-time
version pin. The native buffers carried in the WCF/MDAS body (and in the 2023 R2
gRPC bytes fields) are framed per native interface version; parsing them against
an unexpected version risks silent misinterpretation, so we throw rather than
best-effort parse.
- HistorianServerVersionGate + HistorianServiceInterface: evidence-based
supported versions discovered from a live Historian 2020 server (product
20.0.000) via the wcf-probe command — History=11, Retrieval=4, Transaction=2.
Status' GetInterfaceVersion returns 0, so Status is reachability-only.
- HistorianClientOptions.VerifyServerInterfaceVersion (default true) — bypass
knob for bringing up a server whose reported integers aren't yet captured
(e.g. a 2023 R2 gRPC endpoint carrying the same proven 2020 buffers).
- Wired into both transports' connect paths: WCF history (auth-chain helper) +
retrieval (read orchestrator), and gRPC history + retrieval.
- Mismatch throws ProtocolEvidenceMissingException naming reported/expected
version and the bypass knob.
10 new unit tests (198 total green). Verified the gate does not regress the
proven WCF read path: a live read against the local 2020 server reaches past the
gate (Retr=4 matches) — the only live failures are a pre-existing environmental
read timeout (OperationCanceledException), identical with and without this change.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Stands up HistorianTransport.RemoteGrpc end-to-end for the read path,
built on the recovered 2023 R2 gRPC contract (gRPC-Web/HTTP-1.1, port
32565, gzip). The opaque protobuf `bytes` fields carry the SAME native
binary payloads as the 2020 WCF/MDAS path, so the proven serializers and
parsers are reused unchanged.
- Grpc/Protos/*.proto: 6 protoc-validated contracts recovered from
embedded FileDescriptors (authoritative, not guessed).
- Grpc/HistorianGrpcChannelFactory: GrpcWebHandler/HTTP-1.1 channel,
ResolvePort/ResolveAddress, optional TLS + gzip.
- Grpc/HistorianGrpcReadOrchestrator: mirrors the WCF read chain over
gRPC; auth uses HistoryService.ExchangeKey (the gRPC ValCl op).
- Wcf/HistorianNativeHandshake: transport-agnostic Open2 request builder
+ SSPI/Negotiate token loop + response decode, shared by WCF and gRPC.
- Op map (2020 -> gRPC): ValCl->ExchangeKey, Open2->OpenConnection,
StartQuery2->StartQuery, GetNextQueryResultBuffer2->GetNextQueryResultBuffer.
- HistorianClientOptions: DefaultGrpcPort=32565, GrpcUseTls.
- csproj: Google.Protobuf, Grpc.Net.Client(.Web), Grpc.Tools codegen.
Not yet live-verified against a 2023 R2 server: ExchangeKey is the first
thing to revisit if a live server rejects the handshake; the inner byte
payloads are the proven 2020 protocol. Gated live test via
HISTORIAN_GRPC_HOST. 188 unit tests green; build clean.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
When the server cert's CN/SAN doesn't match the URL host (typical for
installer-generated AVEVA Historian certs that claim DNS=localhost
even when reached over a LAN IP), WCF rejects the channel with
"Identity check failed for outgoing message". Set ServerDnsIdentity
to whatever the cert claims (often "localhost") to satisfy the check.
The endpoint address for the cert binding is constructed with a
DnsEndpointIdentity when the option is non-null.
Default null. Pairs with AllowUntrustedServerCertificate so a Linux
client can talk to a self-signed dev Historian over RemoteTcpCertificate.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
When true, the SDK's WCF channel factories accept the server's X.509
certificate without chain validation. Intended for connecting to
development / on-prem Historians whose /HistCert endpoint presents an
installer-generated self-signed cert that isn't in the local trust
store. Particularly relevant on Linux: .NET WCF on Linux does its own
X509Chain validation that doesn't honor the system CA bundle, so even
after `update-ca-certificates` succeeds the cert binding still rejects
the server. With this option set, custom certificate validator accepts
any cert and revocation checking is disabled.
Default false. Centralized in HistorianWcfClientCredentialsHelper.Configure
and applied at every ChannelFactory<T> instantiation in the WCF layer
(no-op when the option is false). 171/171 Windows tests still pass.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Full read-only SDK (src/AVEVA.Historian.Client) implementing the CLAUDE.md required
surface against AVEVA Historian's binary WCF protocol — no native AVEVA runtime
dependency. All operations live-verified against a local Historian:
- ProbeAsync, ReadRawAsync, ReadAggregateAsync, ReadAtTimeAsync, ReadEventsAsync
- BrowseTagNamesAsync, GetTagMetadataAsync (17 native data-type codes mapped)
- GetConnectionStatusAsync, GetStoreForwardStatusAsync, GetSystemParameterAsync
- 108/108 unit + integration tests pass
Includes the reverse-engineering toolkit (tools/AVEVA.Historian.ReverseEngineering)
used to decode the protocol: WCF probes, IL inspection via dnlib, and IL-rewrite
instrumentation (instrument-wcf-{write,read}message etc.) plus the .NET Framework
trace harness (tools/AVEVA.Historian.NativeTraceHarness) for parity testing.
Sanitized handoff evidence under docs/reverse-engineering/. Native AVEVA binaries
(current/, aveva-install-x64/, aveva-install-x86/) are gitignored — fetch separately
from the AVEVA installer.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Joseph Doherty