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romanett 20c2d77d57 Fix Core/Types audit findings and conform them to the OPC UA spec (stacked on #4569) (#4573)
> **Stacked on #4569.** The base branch is
`romanett/practical-murdock-fd9c56`, so this diff shows only the commits
of this PR. Retarget to `master` after #4569 merges.

## Summary

Bug audit of `Opc.Ua.Core`, `Opc.Ua.Core.Types`, `Opc.Ua.Types` and
`Opc.Ua.Core.Schema`, with the findings fixed and the fixes grounded
against the OPC UA specification (reference.opcfoundation.org). 133
commits in four groups:

1. **Audit fixes** (`Fix <ID>: ...`): 116 findings from a read-only
audit, each with a regression test. IDs follow the audit scopes: T1-T6
`Opc.Ua.Types`, C1-C4 `Opc.Ua.Core`, S1 `Opc.Ua.Core.Types` +
`Opc.Ua.Core.Schema`.
2. **Review fixes** (`Fix review <ID>: ...`): issues a code review of
group 1 found, plus lower-severity leftovers.
3. **Spec fixes** (`Spec: #<n> ...`): the 18 places where an earlier fix
only partly matched the spec text.
4. Test and analyzer follow-ups.

Where `master` (#4516, #4522, #4540, #4564) or #4569 already fixed the
same issue, their version was kept and this PR only adds what they
didn't cover.

## Behaviour and user-facing changes

### Wire format and interoperability (breaking)
- **PubSub AES-CTR (Aes128-CTR / Aes256-CTR)** now follows Part 14
Tables 156/157:
- The counter block is `KeyNonce[4] | MessageNonce[8] |
BlockCounter[4]`, and the block counter starts at 1.
- The SecurityHeader nonce is 8 bytes: `Random[4] | UInt32
SequenceNumber`, with the sequence number starting at 1.
  - SKS key data is split with a 4-byte KeyNonce, giving 52 / 68 bytes.
- **Not interoperable with earlier releases of this stack**, but matches
the spec. There is a test against the independent RFC 3686 vector.
- **User token signature** (Part 4 6.1.8):
- The signed data is now built from the user token policy's
SecurityPolicy on both client and server.
- It also supports the SecurityMode None layout `ServerNonce |
HASH(ServerCertificate) | ClientNonce`.
- New overload `SecurityPolicyInfo.GetUserTokenSignatureData(...,
MessageSecurityMode)`.
- **Secure channel:**
- The ECC AEAD `LastSequenceNumber` is correct across the 32-bit
sequence wrap (Part 6 6.8.1).
  - The incoming chunk counts against MaxChunkCount/MaxMessageSize.
- The sender no longer lets a message through that is 24 bytes over
MaxMessageSize.
- The OPN response signature is verified without overrunning the buffer
(RSA_DH with differing key sizes).

### Sessions (server)
- **CreateSession nonce:**
- The client nonce is kept on None channels, because the None-mode user
token signature covers it.
- A nonce over 128 bytes returns `Bad_NonceInvalid` on every channel
(Part 4 5.7.2.3).
  - The duplicate-nonce check runs only on secured channels.
- A non-empty nonce under 32 bytes is still accepted on None, for
compatibility.
- **ActivateSession:** an embedded `EccEncryptedSecret` signing
certificate is validated with the server's peer certificate validator
(Part 6 6.8.3). Byte equality with the client certificate is only the
fallback when no validator is available. New opt-in interface
`ICertificateValidatorProvider`.
- **FindServers / GetEndpoints:** `GatewayServerUri` and
`DiscoveryProfileUri` are no longer swapped.

### Write, Read and Call (NodeState / node managers)
- **UserWriteMask:**
- Enforced for non-value attributes and for VariableType Value writes
(`ValueForVariableType`), returning `Bad_UserAccessDenied`.
- An unconfigured UserWriteMask (0, no handler) is not enforced, and
reads back as the WriteMask so Read and Write agree (Part 3 8.60).
- A throwing or Bad `OnReadUserWriteMask` handler fails only that item.
- **Index-range writes:**
- Slices are merged into the cached value under the attribute lock, also
for `OnWriteValueAsync` handlers.
- A data-change notification is still produced when the cache cannot
absorb the slice.
- The slice must match the unclipped range, otherwise
`Bad_IndexRangeDataMismatch` (new status code in `Opc.Ua.Types`).
  - A range past the target returns `Bad_IndexRangeNoData`.
- A handler without index-range support returns `Bad_WriteNotSupported`
(Part 4 7.27, 5.11.4.4).
- **Index-range reads on matrices** return partial results clipped to
the source, instead of allocating the requested size (a Read with
`"0:40000,0:40000"` no longer allocates about 1.6e9 elements).
- **DataTypeDefinition writes:**
- A value that isn't a decoded DataTypeDefinition, or whose kind doesn't
match the DataType category, returns `Bad_TypeMismatch`.
  - Null is rejected for concrete Structure/Enumeration/OptionSet types.
  - WriteMask is checked first (Part 3 5.8.3).
- **AnalogItem:** a null write skips the InstrumentRange check again.
- **Method call:** the async fallback passes the ObjectId to the method
handlers.
- **Redundancy:** `DistributedValueParticipation` merges index-range
writes and applies the index range on reads.
- **Change masks:** `ClearChangeMasks` takes the bits atomically, so
concurrent changes are no longer lost.
- **`AccessLevelEx`:** preserved by Clone/Export.

### Alarms & Conditions (Part 9)
- **Acknowledge / Confirm / AddComment:**
- Accept any EventId the condition or its branches reported while that
state is still pending (5.7.3).
  - An unknown id returns `Bad_EventIdUnknown`.
- An already handled state returns `Bad_ConditionBranchAlreadyAcked` /
`...AlreadyConfirmed`.
- AddComment on a branch no longer changes the trunk, and the branch
table is re-keyed when a branch's EventId changes.
- **Shelving:**
  - OneShotShelve without MaxTimeShelved no longer overflows the timer.
- A timed shelve is measured on the monotonic clock, so wall-clock steps
don't delay the unshelve.
  - The state is named `OneShotShelved`.
- **Audit events:**
  - They report failure for rejected method calls.
  - `SelectedResponse` is a UInt32.
  - A rejected negative Respond leaves SelectedResponse unset.
- **`ContentFilterElement.Validate`:** an unknown FilterOperator is
reported per element as `Bad_FilterOperatorInvalid`, instead of failing
the whole service call.

### ContentFilter evaluation (Part 4 7.7.3, on top of #4564)
- **Bitwise operators:**
  - The result takes the size of the larger operand.
- Boolean, numeric String and one-element array operands are converted
to integers implicitly.
  - Types without an implicit integer conversion give NULL.
- **Strings:** ordering is ordinal, no longer culture dependent.
- **Cast:** restricted to the Table 121 conversions, and QualifiedName
to LocalizedText is added. The general `Variant.ConvertTo` keeps its
wider set.
- **Null and empty operands:**
  - `Like` with a NULL operand is NULL.
  - Empty arrays of the same DataType compare equal.
  - Null-string operands are NULL everywhere.

### Encoders and built-in types
- **XML:**
- Strings keep leading, trailing and whitespace-only content (Part 6
5.3.1.5). NodeSet import opts back into treating whitespace-only strings
as empty with the new `XmlDecoder.TreatWhitespaceOnlyStringsAsEmpty`.
- Layout whitespace around `<Identifier>` values is ignored, and
trailing control characters are stripped from `s=` ids.
  - `XmlElement` ignores DTDs without expanding entities.
- **JSON:**
  - A DateTime without an offset is read as UTC.
- An unmappable `nsu=` NodeId and an unknown `svu=` ExpandedNodeId
decode to a namespace-0 String NodeId (5.4.2.10 / 5.4.2.11).
  - `svr=` is rejected in a NodeId field.
  - Bad matrix dimensions return `BadDecodingError`.
  - The non-strict body stack stays balanced after an error.
  - The nesting limits match between encoder and decoder.
- **Binary:**
  - `MaxByteStringLength` no longer applies to strings.
- ExtensionObject bodies count toward the nesting limit on seekable
streams (and in the XML encoder).
- **Parsing:**
  - The NodeId parser requires `i=`/`s=`/`g=`/`b=`.
  - `ExpandedNodeId.Parse` rejects an empty `nsu=`/`svu=`.
  - NumericRange rejects a trailing `,` with `Bad_IndexRangeInvalid`.
  - RelativePath escapes `#`.
- **Status codes:** `StatusCode.WithSubCode`/`WithCodeBits` keep the
severity bits and look up the symbolic id for the new code.
- **Variant / VariantHelper:**
- `TryCastTo` returns false on a type mismatch. So
`DataValue.GetValue<T>(default)` returns the default, and
`GetValueOrDefault` / `CastTo` throw `BadTypeMismatch` as documented.
  - `System.DateTime` casts are supported.
  - Concrete encodeable arrays (e.g. `Argument[]`) no longer throw.
- `ConvertTo` keeps one-element and empty arrays as arrays and checks
the conversion is legal for empty arrays.
- `CastFrom(object[])`, `CastFrom(Enum[])` and the obsolete
`Variant(object)` constructors keep the array shape (previously a
one-element array collapsed to a scalar and an empty one to Null).
- `TypeInfo.Unknown` / `Variant.Null.TypeInfo` report `ValueRanks.Any`.
- **Equality and hashing contracts fixed:**
- Types: Matrix/MatrixOf, typed-null Variants, NodeId (the namespace
index is now hashed), ExpandedNodeId, LocalizedText, DiagnosticInfo,
StructureDefinition/EnumDefinition, CertificateIdentifier, UserIdentity
and DateTimeUtc.
  - `MatrixOf.Dimensions` returns a copy.
  - Decimal equality and hashing now run in bounded time.
- **Localized text:** a LocalizedText with locale `"mul"` and no usable
translations, or null client locale ids, no longer throw.

### NodeSet, address space and utilities
- **NodeSet export/import:**
- Server index 0 is the local server on import and export, so local ids
are no longer written as `svr=65535`.
- `StructureDefinition.BaseDataType` is filled from the supertype on
import.
- **`NodeTable.Import`:** replaces duplicates, keeping the references
neighbouring nodes hold. `TypeTable.Add` detaches a re-parented type
from its old supertype, and `Node.Clone` gets its own ReferenceTable.
- **`StringTable` / `NamespaceTable`:** capped at UInt16 indexes
(`BadEncodingLimitsExceeded`) for Append and Update, instead of silently
wrapping.
- **Small fixes:**
  - `UnsecureRandom.Shared` is seeded randomly.
  - The peer's RetryAfterMs is clamped to one day.
- The `CancelAsync` and `string.GetHashCode(StringComparison)` polyfills
match BCL behaviour.
  - `CoreUtils.IsEqual` compares strings ordinally.

### Schema generation and ComplexTypeSystem
- **JSON schema:** describes the 1.05 layout with the compact/verbose
null rules, and now validates real `JsonEncoder` output.
- **XSD:**
- `EncodingMask` (`xs:unsignedLong`) only for
StructureWithOptionalFields.
  - Guid and StatusCode are complex types.
  - Standard types are in the `Types.xsd` namespace.
- **Structure-backed OptionSets** are described as `{Value, ValidBits}`.
New `UaTypeDescription.IsStructureOptionSet` property and constructor
overload.
- **ComplexTypeSystem:**
- A malformed type in a server dictionary is skipped per type instead of
discarding the whole dictionary.
  - Cyclic supertype walks are bounded.
  - Declared definitions are no longer changed.
  - A dictionary validator is kept only if the dictionary parsed.

### Certificates and trust lists (Part 4 6.1.3, Part 12)
- **Revocation:**
- Checked for issuers supplied in the peer's chain and for
inline-trusted issuers, against the CRLs in the trusted and issuer
stores.
  - A store without CRL support no longer hides "revocation unknown".
- `RejectUnknownRevocationStatus` is honoured for inline-trusted issuers
unless the entry sets `SuppressRevocationStatusUnknown`. This changes
the strict case of `ExplicitIssuerChainIsHonoredWithoutStorePathAsync`.
- **Basic constraints / path length** violations fail with
`Bad_CertificateInvalid`.
- **`TreatAsInvalid`:**
- Now yields `Bad_CertificateUntrusted`, which can't be suppressed or
auto-accepted.
- It is honoured on individual trust-list entries even when the
certificate is also in a store.
- **`EccEncryptedSecret`:** enforces the result of validating the sender
certificate.
- **`TrustListTransaction`:**
- Routes each CRL to the store holding its issuer
(TrustedCrls/IssuerCrls).
- Validates staged CRLs, including the store's CRL support, before
changing anything.
  - Applies certificates before CRLs.
- **Other:**
- One failing `CertificateChanges` observer no longer stops the others.
- `InMemory:` stores share their contents per path, and
`InMemoryStoreProvider` is `IDisposable`.

### WoT (`Opc.Ua.Types/Wot`)
- **Projection security:** projection security schemes whose qualified
names collide are refused. New diagnostic
`WotDiagnosticCode.ProjectionSecurityConflict = 6063`.
- **Input handling:**
- Invalid Unicode (lone surrogates, bad UTF-8) is rejected as
`JsonException`.
  - External-schema results are keyed per affordance.
  - A duplicate security-floor member is rejected.
  - `nsu=` ids are percent-encoded (Part 6 5.1.12).
  - The configured JSON depth is honoured on re-parse.
  - An oversized document is reported before it is parsed back.
- **Performance and limits:**
- Subtype-graph validation, `componentOf` linking and the namespace
table are now linear.
  - Namespaces are capped at UInt16.

### New or changed public API
- `ICertificateValidatorProvider` (server)
- `SecurityPolicyInfo.GetUserTokenSignatureData(...,
MessageSecurityMode)` overload
- `XmlDecoder.TreatWhitespaceOnlyStringsAsEmpty`
- `UaTypeDescription.IsStructureOptionSet` plus a constructor overload
- `WotDiagnosticCode.ProjectionSecurityConflict`
- `StatusCodes.BadIndexRangeDataMismatch` in the `Opc.Ua.Types` list
- `InMemoryStoreProvider : IDisposable`

## Not changed / open
- **Deferred:**
- S1-14 (BSD OptionSet size needs the base type in `UaTypeDescription`,
and BSD is deprecated).
- C2-7 (restoring the own-certificate trust exemption would accept
certificates the spec says to reject; removing the dead code is a
separate decision).
- A1-4 (config values keep surrounding whitespace, as the pre-April-2026
loader did).
  - H-2 (JsonDecoder has no real nesting counter).
- A2-3 (the StringTable cap also applies to diagnostics tables; default
`MaxArrayLength` already bounds them).
- **Needs a product decision:**
- The general `ConvertToString` writes a QualifiedName as `ns:Name`,
while Table 121 drops the namespace.
  - Short (< 32 byte) client nonces are accepted on None channels.

## Verification
- Every commit added a regression test that fails without its fix, where
practical.
- Before the rebases, with all audit and review fixes (before the `Spec:
#…` commits): 0 build warnings and 16 test suites green on net10.0. The
suites: Types, Core, Core.Encoders, Core.Security, Core.Schema, Client,
Client.ComplexTypes, Server, Sessions, Gds, History, Features,
Redundancy.Server, PubSub, WotCon and WotCon.Bindings. Core hit its
known intermittent end-of-run hang once, and reruns were clean.
- The `Spec: #…` fixes were verified per group on their own suites.
Those include PubSub.Udp, Redundancy.PubSub, PubSub.Server,
Configuration and SourceGeneration.Core.
- **Not yet built or tested on this base.** It was rebased onto master
(resolving overlaps with #4522, #4540 and #4564) and then onto #4569.
This PR stays a draft until the full run on this base is green.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: marcschier <11168470+marcschier@users.noreply.github.com>
Co-authored-by: Marc Schier <marcschier@users.noreply.github.com>
2026-09-29 11:14:15 +00:00
..

Opc.Ua.PubSub.Tests benchmarks

BenchmarkDotNet suite covering the four hot paths of the Part 14 v1.05.06 PubSub stack: UADP encode/decode, JSON encode/decode, scheduler tick dispatch, and AES-128-CTR sign+encrypt.

Quick smoke pass

The dry-run smoke pass takes ~10 seconds, runs every benchmark exactly once, and emits a summary table that can be diffed for catastrophic regressions:

dotnet run -c Release -p tests\Opc.Ua.PubSub.Tests\Opc.Ua.PubSub.Tests.csproj `
  -f net10.0 -- --job dry --filter '*' --inProcess

The reference output for the most recent commit is checked in at Baselines/baseline-net10-dry.md.

The --inProcess flag forces InProcessEmitToolchain. Without it BenchmarkDotNet generates a satellite project that doesn't honour our solution's Directory.Build.props and Directory.Build.targets, so the source generators don't run (MODELGEN003). The in-process toolchain runs benchmarks in the BDN host process and is the only toolchain that works without bespoke BDN configuration.

Real benchmark runs

--job dry is not statistically valid (one warm-up + one iteration). For real numbers use one of the longer jobs:

# ~5 minutes total. Single launch, ~3 iterations per benchmark.
dotnet run -c Release -p tests\Opc.Ua.PubSub.Tests\Opc.Ua.PubSub.Tests.csproj `
  -f net10.0 -- --job short --filter '*' --inProcess

# ~30 minutes total. Multiple launches, ~15 iterations each.
dotnet run -c Release -p tests\Opc.Ua.PubSub.Tests\Opc.Ua.PubSub.Tests.csproj `
  -f net10.0 -- --job medium --filter '*' --inProcess

# ~3 hours total. The defaults — full statistical pipeline.
dotnet run -c Release -p tests\Opc.Ua.PubSub.Tests\Opc.Ua.PubSub.Tests.csproj `
  -f net10.0 -- --filter '*' --inProcess

Filter to one suite to iterate locally:

dotnet run -c Release -p tests\Opc.Ua.PubSub.Tests\Opc.Ua.PubSub.Tests.csproj `
  -f net10.0 -- --filter '*UadpEncoding*' --inProcess

Output lands under BenchmarkDotNet.Artifacts/results/ next to the project. To save outside the repo:

dotnet run -c Release -p tests\Opc.Ua.PubSub.Tests\Opc.Ua.PubSub.Tests.csproj `
  -f net10.0 -- --filter '*' --inProcess `
  --artifacts $env:USERPROFILE\bench-results

Baselines

Baselines/ holds the smoke-pass summary tables that this commit was verified against.

When a hot-path change is intentional, regenerate the baseline by re-running the smoke pass and committing the updated table in the same PR.

Suites

  • UadpEncodingBenchmarks — UADP EncodeAsync / TryDecodeAsync across SingleField (UInt32), TenFields (mixed primitives), HundredFields (mixed primitives), Strings (10×64 char fields), LargeArray (Float[256]).
  • JsonEncodingBenchmarks — Same dataset shapes, two encoder modes (Verbose, Compact).
  • SchedulerBenchmarks — IPubSubScheduler register-and-dispatch latency across 1, 10, 100, 1000 concurrent schedules.
  • SecurityBenchmarks — UadpSecurityWrapper AES-128-CTR sign+encrypt wrap/unwrap across 64, 256, 1024-byte payloads.

All suites use [MemoryDiagnoser] so every result table includes per-op allocation in the Allocated column.