Closes task #120 (partial — strict point-check; ancestor-visibility implication is a follow-up). Before this commit DriverNodeManager exposed every materialized node to every browsing session regardless of the user's ACL. Read + Write + HistoryRead were already gated through AuthorizationGate in Phase 6.2 Stream C core; Browse was the one surface where the session could still enumerate nodes it had no permission to touch, discovering structure even when reads failed with BadUserAccessDenied. Implementation - New `Browse` override on DriverNodeManager that calls base.Browse first (lets the stack populate the reference list normally), then post-filters the IList<ReferenceDescription> so denied nodes are removed silently. OPC UA convention: Browse filtering is invisible to the client; no BadUserAccessDenied surfaces. - Extracted the filter loop into the static internal `FilterBrowseReferences(references, userIdentity, gate, scopeResolver)` so the policy is unit-testable without standing up the full OPC UA server stack. - Non-string NodeId identifiers (stack-synthesized standard-type references with numeric identifiers) bypass the gate — only driver- materialized nodes key into the authz trie. - When AuthorizationGate or NodeScopeResolver is null, the filter is a no-op — preserves the pre-Phase-6.2 dispatch path for integration tests that construct DriverNodeManager without authz. Tests — 6 new in BrowseGatingTests.cs (gate-null no-op, empty-list no-op, denied-removed, allowed-passes-through, numeric-id bypass, lax-mode null-identity keeps references). Server.Tests 257 → 263. Known follow-up (tracked implicitly under #120 re-scope): - Ancestor-visibility implication (acl-design.md §Browse line 111): a user with Read at `Line/Tag` should be able to Browse `Line` even without an explicit Browse grant. Current filter does a strict point-check. Proper fix needs TriePermissionEvaluator to expose a "subtree-has-any-grant" query. - TranslateBrowsePathsToNodeIds not yet filtered (same extension pattern; small follow-up). Docs: v2-release-readiness.md Phase 6.2 Stream C hardening list marks the Browse bullet struck-through with "Partial" close-out note. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
OtOpcUa documentation
Two tiers of documentation live here:
- Current reference at the top level (
docs/*.md) — describes what's shipped today. Start here for operator + integrator reference. - Implementation history + design notes at
docs/v2/*.md— the authoritative plan + decision log the current reference is built from. Start here when you need the why behind an architectural choice, or when a top-level doc says "see plan.md § X".
The project was originally called LmxOpcUa (a single-driver Galaxy/MXAccess OPC UA server) and has since become OtOpcUa, a multi-driver OPC UA server platform. Any lingering LmxOpcUa-string in a path you see in docs is a deliberate residual (executable name lmxopcua-cli, client PKI folder {LocalAppData}/LmxOpcUaClient/) — fixing those requires migration shims + is tracked as follow-ups.
Platform overview
- Core owns the OPC UA stack, address space, session/security/subscription machinery.
- Drivers plug in via capability interfaces in
ZB.MOM.WW.OtOpcUa.Core.Abstractions:IDriver,IReadable,IWritable,ITagDiscovery,ISubscribable,IHostConnectivityProbe,IAlarmSource,IHistoryProvider,IPerCallHostResolver. Each driver opts into whichever it supports. - Server is the OPC UA endpoint process (net10, x64). Hosts every driver except Galaxy in-process; talks to Galaxy via a named pipe because MXAccess COM is 32-bit-only.
- Admin is the Blazor Server operator UI (net10, x64). Owns the Config DB draft/publish flow, ACL + role-grant authoring, fleet status +
/metricsscrape endpoint. - Galaxy.Host is a .NET Framework 4.8 x86 Windows service that wraps MXAccess COM on an STA thread for the Galaxy driver.
Where to find what
Architecture + data-path reference
| Doc | Covers |
|---|---|
| OpcUaServer.md | Top-level server architecture — Core, driver dispatch, Config DB, generations |
| AddressSpace.md | GenericDriverNodeManager + ITagDiscovery + IAddressSpaceBuilder |
| ReadWriteOperations.md | OPC UA Read/Write → CapabilityInvoker → IReadable/IWritable |
| Subscriptions.md | Monitored items → ISubscribable + per-driver subscription refcount |
| AlarmTracking.md | IAlarmSource + AlarmSurfaceInvoker + OPC UA alarm conditions |
| DataTypeMapping.md | Per-driver DriverAttributeInfo → OPC UA variable types |
| IncrementalSync.md | Address-space rebuild on redeploy + sp_ComputeGenerationDiff |
| HistoricalDataAccess.md | IHistoryProvider as a per-driver optional capability |
| VirtualTags.md | Core.Scripting + Core.VirtualTags — Roslyn script sandbox, engine, dispatch alongside driver tags |
| ScriptedAlarms.md | Core.ScriptedAlarms — script-predicate IAlarmSource + Part 9 state machine |
Two Core subsystems are shipped without a dedicated top-level doc; see the section in the linked doc:
| Project | See |
|---|---|
Core.AlarmHistorian |
AlarmTracking.md § Alarm historian sink |
Analyzers (Roslyn OTOPCUA0001) |
security.md § OTOPCUA0001 Analyzer |
Drivers
| Doc | Covers |
|---|---|
| drivers/README.md | Index of the eight shipped drivers + capability matrix |
| drivers/Galaxy.md | Galaxy driver — MXAccess bridge, Host/Proxy split, named-pipe IPC |
| drivers/Galaxy-Repository.md | Galaxy-specific discovery via the ZB SQL database |
For Modbus / S7 / AB CIP / AB Legacy / TwinCAT / FOCAS / OPC UA Client specifics, see v2/driver-specs.md.
Operational
| Doc | Covers |
|---|---|
| Configuration.md | appsettings bootstrap + Config DB + Admin UI draft/publish |
| security.md | Transport security profiles, LDAP auth, ACL trie, role grants, OTOPCUA0001 analyzer |
| Redundancy.md | RedundancyCoordinator, ServiceLevelCalculator, apply-lease, Prometheus metrics |
| ServiceHosting.md | Three-process deploy (Server + Admin + Galaxy.Host) install/uninstall |
| StatusDashboard.md | Pointer — superseded by v2/admin-ui.md |
Client tooling
| Doc | Covers |
|---|---|
| Client.CLI.md | otopcua-cli — OPC UA command-line client |
| Client.UI.md | Avalonia desktop client |
| DriverClis.md | Driver test-client CLIs — index + shared commands |
| Driver.Modbus.Cli.md | otopcua-modbus-cli — Modbus-TCP |
| Driver.AbCip.Cli.md | otopcua-abcip-cli — ControlLogix / CompactLogix / Micro800 / GuardLogix |
| Driver.AbLegacy.Cli.md | otopcua-ablegacy-cli — SLC / MicroLogix / PLC-5 (PCCC) |
| Driver.S7.Cli.md | otopcua-s7-cli — Siemens S7-300 / S7-400 / S7-1200 / S7-1500 |
| Driver.TwinCAT.Cli.md | otopcua-twincat-cli — Beckhoff TwinCAT 2/3 ADS |
| Driver.FOCAS.Cli.md | otopcua-focas-cli — Fanuc FOCAS/2 CNC |
Requirements
| Doc | Covers |
|---|---|
| reqs/HighLevelReqs.md | HLRs — numbered system-level requirements |
| reqs/OpcUaServerReqs.md | OPC UA server-layer reqs |
| reqs/ServiceHostReqs.md | Per-process hosting reqs |
| reqs/ClientRequirements.md | Client CLI + UI reqs |
| reqs/GalaxyRepositoryReqs.md | Galaxy-scoped repository reqs |
| reqs/MxAccessClientReqs.md | Galaxy-scoped MXAccess reqs |
| reqs/StatusDashboardReqs.md | Pointer — superseded by Admin UI |
Implementation history (docs/v2/)
Design decisions + phase plans + execution notes. Load-bearing cross-references from the top-level docs:
- v2/plan.md — authoritative v2 vision doc + numbered decision log (referenced as "decision #N" elsewhere)
- v2/admin-ui.md — Admin UI spec
- v2/acl-design.md — data-plane ACL + permission-trie design (Phase 6.2)
- v2/config-db-schema.md — Config DB schema reference
- v2/driver-specs.md — per-driver addressing + quirks for every shipped protocol
- v2/dev-environment.md — dev-box bootstrap
- v2/test-data-sources.md — integration-test simulator matrix (includes the pinned libplctag
ab_serverversion for AB CIP tests) - v2/implementation/phase--.md — per-phase execution plans with exit-gate evidence