Commit Graph

30 Commits

Author SHA1 Message Date
romanett 1fb1134974 Tests: scope MeterListeners to the meter under test (fix flaky ClientBaseTests metrics test) (#4708)
## Problem

`ClientBaseTests.ActivityTraceFlags_Metrics_ShouldRecordMetricsOnly`
failed intermittently in full-suite runs:

```
Expected: "opc.ua.client.request.duration"
But was:  "opc.ua.channel.reconnect.duration"
```

`TelemetryContextBase.CreateMeter()` returns a new `Meter` per call,
named after the calling assembly, so `ClientBase`'s meter and
`ClientChannelManagerMetrics`' meter are both named `Opc.Ua.Core`.
`TestMeterListener` enabled every instrument whose `Meter.Name` matched,
so reconnect-duration measurements from `[Parallelizable]` channel
manager fixtures were recorded and could precede the request duration.

## Fix (test-only)

- `ClientBaseTests.TestMeterListener`: enable instruments only when
`ReferenceEquals(instrument.Meter, meter)`, i.e. the meter instance the
client under test created. Assertions unchanged.
- `CryptoProviderModelTests.AuditorPublishesAProviderMetric`: same flaw
— it enabled every `opc.ua.crypto*` instrument process-wide (fixture is
`ParallelScope.All`), so another auditor's uncertified gauge could
overwrite the observed count. Now scoped to the auditor's own meter
(read via reflection, as `ClientBaseTests` already does for
`ClientBase`).

Other `MeterListener` users reviewed and left as-is: `NodeCacheTests` /
`AdapterMetricsTests` are non-parallel fixtures; channel manager
listeners only assert existence and filter by endpoint tag.

## Verification

- `ClientBaseTests` + `CryptoProviderModelTests`: 4× consecutive, 25/25.
- `FullyQualifiedName~Opc.Ua.Core.Tests.Stack` (net10.0): 2 clean
passes, 3548 passed / 80 skipped. One attempt hung in unrelated
`ClientChannelManagerManagedTests` async tests
(`ReconnectAsyncNotifiesAttachedParticipantsAsync` /
`ReleasingOneLeaseKeepsChannelAliveForOtherAsync`) and was rerun — a
separate intermittent hang.
- net48 build of `Opc.Ua.Core.Tests`: 0 warnings, 0 errors; `dotnet
format whitespace` clean.

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

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-09 11:07:46 +02:00
romanett 7fe7794a19 Enable AES-GCM and ChaCha20-Poly1305 policies on net48 via BouncyCastle (stacked on #4703) (#4705)
> Follow-up to #4703 (now merged to master; this PR has been retargeted
to `master`).

Part of #4510. #4703 enabled the CBC ECC policies on net48 through a
BouncyCastle raw-ECDH polyfill. The AEAD policies were still unavailable
there because .NET Framework has no `AesGcm` or `ChaCha20Poly1305`. This
PR adds those ciphers the same way, so on net48 all of these are now
offered:
`ECC_{nistP256,nistP384,brainpoolP256r1,brainpoolP384r1}_AesGcm` /
`_ChaChaPoly`, `RSA_DH_AesGcm`, `RSA_DH_ChaChaPoly`.

## Changes
- **Polyfill**
`src/Opc.Ua.Security.Certificates/Org.BouncyCastle/AeadCiphers.cs`
(internal, `#if NETFRAMEWORK`, next to `EcdhRawAgreement`): `AesGcm` and
`ChaCha20Poly1305` types with the .NET 8 BCL surface. They wrap
BouncyCastle's `GcmBlockCipher(AesEngine)` and
`Org.BouncyCastle.Crypto.Modes.ChaCha20Poly1305`.
- A tag mismatch throws `CryptographicException`, never BC's
`InvalidCipherTextException`, so
`PlatformSymmetricCryptoProvider.DecryptAuthenticated` still returns
`false` and the channel still raises a protocol error.
- GCM releases plaintext blocks before it checks the tag, so plaintext
stays in a scratch buffer and is copied out only after the tag verifies.
On failure the destination is cleared, as the BCL does. Scratch buffers
and the key copy are zeroed.
- **Opc.Ua.Core**: aliases the polyfill types on `NETFRAMEWORK` and
removes the `NET8_0_OR_GREATER` gates in `SecurityPolicies`
(`SupportsAesGcmPolicy` / `SupportsChaCha20Poly1305Policy`),
`CryptoUtils` (`SymmetricEncryptAndSign` / `SymmetricDecryptAndVerify`,
AEAD helpers) and `PlatformSymmetricCryptoProvider`. The channel, the
provider facet and the encrypted ECC user tokens (`EncryptedSecret`,
through `CryptoUtils`) now run the same code on every target. .NET 8+
keeps the BCL ciphers.
- **FIPS** (requested by the #4703 session, after a2ecf13b1): under
`CryptoCompliancePolicy.FipsOnly`, `CryptoCompliance.IsPolicyPermitted`
now also withholds every AEAD policy on .NET Framework. That adds
`RSA_DH_AesGcm`, which is FIPS-approved and not ECC. The BouncyCastle
cipher runs outside any validated module and the user-token path
bypasses the provider registry, so the auditor cannot see it. Tests and
`docs/CryptoProvider.md` are updated to match.
- **Docs**: EccProfiles (Known Limitations), migration `certificates.md`
(and the bundled skill copy), ProductionChecklist, Profiles,
WhatsNewIn2.0, CryptoProvider. They state that on net48 these primitives
run in managed BouncyCastle, which is not a validated (FIPS) module and
not hardware-accelerated or hardened against cache-timing attacks like
CNG AES.

## Tests
- New `AeadPolyfillTests` (Core.Tests):
- Known answers: NIST GCM test cases 2/4 (AES-128) and 14/16 (AES-256),
plus RFC 8439 §2.8.2 for ChaCha20-Poly1305. They run through
`PlatformSymmetricCryptoProvider` on every TFM and through the polyfill
directly.
- Tampering with the tag, the ciphertext or the AAD gives `false` from
the provider, and `CryptographicException` with a cleared plaintext from
the polyfill.
  - Argument validation.
- **BCL cross-check:** on .NET 8+, Core.Tests also compiles
`AeadCiphers.cs` (`AEAD_POLYFILL_CROSSCHECK`, test-only
`BouncyCastle.Cryptography` reference). Polyfill and BCL must produce
identical ciphertext and tag, and each must decrypt the other's output:
3 algorithms × 8 message lengths (0 to 8192) × 3 AAD lengths.
- `CryptoProviderRegistryTests`: `RSA_DH_AesGcm` is permitted under
FipsOnly only off .NET Framework and withheld on it.
- Tests that `Assert.Ignore` when AEAD is unavailable now run on net48,
e.g. `EccSecretRejectsDifferentNegotiatedPolicyAsync` and the
`RSA_DH_AesGcm` server session tests.

### Local results
| Run | Result |
|---|---|
| Core.Tests net48, full (before the FIPS commit) | 6049 passed, 0
failed, 88 skipped |
| Core.Tests crypto/AEAD/ECC/EncryptedSecret/Nonce subset, net48 /
net10.0 | 278 / 343 passed, 0 skipped |
| Server.Tests session-security/ECC subset, net48 | 128 passed, 0
skipped |
| `EccInteropTests` net48 vs **open62541 1.5.8 (OpenSSL)** peer | all 16
AEAD cases pass, 4 of them two-renewal token-renewal runs
(`ECC_nistP256_AesGcm`/`_ChaChaPoly` × Sign/SignAndEncrypt ×
Anonymous/UserName, both directions). Remaining 8 failures are the
documented open62541 CBC Sign-only HKDF differences in
`expected-differences.json` |
| `EccInteropTests` net48 vs 1.5.378 LegacyPeer | unchanged 26 passed /
28 skipped |

Note on the acceptance criterion: the 1.5.378 LegacyPeer does not
implement the AEAD policies, so its
`_AesGcm`/`_ChaChaPoly`/`*AeadTokenRenewalAsync` cases skip on every TFM
("The peer (UA-.NETStandard) does not declare …"). Before this PR they
skipped on the 2.0 side; now they get past it and stop at the peer
check. The open62541 peer is the real cross-stack check of the net48
AEAD path against a non-BouncyCastle implementation.

## PubSub DTLS on net48
The DTLS 1.3 transport (`src/Opc.Ua.PubSub.Udp/Dtls`) was compiled out
on .NET Framework, so net48 registered no DTLS profiles. It now reuses
the same polyfills (`Opc.Ua.Security.Certificates` gains
`InternalsVisibleTo Opc.Ua.PubSub.Udp`):
- The `NET8_0_OR_GREATER` gates in the handshake, ECDHE, record
protection and profile probe are removed.
- Two .NET 8 APIs get net48 fallbacks: the AES-ECB record-number mask
uses `CreateEncryptor`, and the handshake random uses
`RandomNumberGenerator.Create`.
- The HKDF probe now checks the managed `DtlsHkdf` that the key schedule
actually uses.
- The public `IsAeadSupported` / `IsRawSharedSecretSupported` probes are
kept and now return `true` everywhere.
- The DTLS tests now also run on net48. The net48 "registers no
profiles" test now asserts that the NIST AEAD profiles are registered.
The socket transport-peer tests and the benchmarks stay .NET 8-only
because they use .NET 8 socket APIs.
- `docs/PubSub.md` DTLS profile table: the net48 column is updated.

Results: PubSub.Udp.Tests net48, full suite: **229 passed, 0 skipped**.
It includes complete NIST AEAD, brainpool and integrity-only handshakes
and ChaCha20 records. The DTLS subset is 76 on net48 vs 81 on net10.0;
the 5 still-gated socket-peer tests are the difference.

Note: DTLS profile selection does not consult `CryptoCompliancePolicy`
on any target. That is pre-existing and unchanged here.

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---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-09 06:30:14 +02:00
romanett d552634258 Enable ECC security policies on net48 via a BouncyCastle raw-ECDH polyfill (#4703)
Closes #4510.

## Summary

OPC UA Part 6 feeds the **raw** ECDH shared secret into HKDF. .NET
Framework only exposes `ECDiffieHellman.DeriveKeyMaterial`, which always
hashes it, so the ECC SecureChannel and user-token policies were
unavailable on `net48` (`SecurityPolicies.GetInfo` returned `null`).

This adds a BouncyCastle polyfill for just that primitive:

-
**`Opc.Ua.Security.Certificates/Org.BouncyCastle/EcdhRawAgreement.cs`**
(`net48` only): an internal `DeriveRawSecretAgreement(this
ECDiffieHellman, ECDiffieHellmanPublicKey)` extension using
`ECDHBasicAgreement`. It returns the X coordinate padded to the field
size, exactly like the .NET 8 BCL method. Keys stay CNG keys; ECDSA
signatures and HKDF stay on the platform — only the agreement step is
managed code. The point is validated (on curve, not infinity) and
mismatched curves are rejected.
- Because the extension mirrors the .NET 8 signature,
`Nonce.GenerateSecret` now has one code path on every target.
- `SupportsRawEccSecretAgreement()` is removed; the CBC-based ECC
policies (`ECC_nistP256`, `ECC_nistP384`, `ECC_brainpoolP256r1`,
`ECC_brainpoolP384r1`) are offered on every target (still subject to OS
curve support).
- BouncyCastle was already a `net48` dependency of
`Opc.Ua.Security.Certificates`; no new package. (Only `net48` is
downlevel now — `netstandard2.1`/`net472` from the issue text are no
longer targets.)

**Not in scope:** the `_AesGcm` / `_ChaChaPoly` ECC variants (and PubSub
DTLS) still need .NET 8 because .NET Framework has no AEAD ciphers —
follow-up stacked on this branch.

## Docs

`EccProfiles.md` (Known limitations), `migrate/2.0.x/certificates.md`,
`ProductionChecklist.md`, `Profiles.md`, `WhatsNewIn2.0.md`. Calls out
that on `net48` the agreement step does not run in a FIPS/validated
module.

## Tests (local)

| Suite | Result |
|---|---|
| `Opc.Ua.Core.Tests` full, net48 | 5956 passed, 0 failed |
| `EccInteropTests` net48 vs 1.5.378 peer (net8.0, native raw ECDH) | 26
passed; 28 skipped (AEAD + curve25519/448) — all four CBC curves, both
directions, UserName tokens, token renewal |
| `Opc.Ua.Sessions.Tests` ECC filter, net48 | 52 passed, 0 failed |
| Server `SessionCoverageTests`/`EphemeralNonce*`, Configuration builder
tests, net48 | all pass |
| Nonce/ECC/EncryptedSecret + session tests, net10.0 | all pass |

New tests: symmetric agreement on all four curves; on net48 an oracle
against CNG (`SHA256(raw) == DeriveKeyFromHash`); curve mismatch and
off-curve rejection. Tests that asserted the old net48 limitation were
updated.

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-08 21:52:44 +02:00
romanett 9b034f8291 Enable nullable reference types centrally; migrate all unset and annotations-only projects (#4700)
# Description

Nullable reference types are now enabled once, in `common.props`, and
every project in the repository builds warning-clean with them.

**Configuration**
- `<Nullable>enable</Nullable>` lives in `common.props`. All per-project
`<Nullable>` settings are removed: 178 project files (enable,
annotations, and the `disable` in the three Aot test projects).
- 419 per-file `#nullable enable`/`restore` directives and the 4
`#nullable disable` directives are removed.
- Kept on purpose:
- The 5 `<auto-generated>` schema files (`UANodeSet.cs`, `UA Type
Dictionary.cs`, `OPCBinarySchema.cs`, `SecuredApplication.cs`,
`PInvokeHelper.cs`) keep `#nullable enable`. The compiler ignores the
project setting in generated code, so the directive is required there.
- `tests/Opc.Ua.Interop.LegacyPeer` keeps `disable`. It builds against
the 1.5.378 packages and does not import the repository props.
- `docs/DeveloperGuide.md` and `.github/copilot-instructions.md` now
describe the central setting.

**Migration** (the 43 unset and 13 annotations-only projects, roughly
10k diagnostics)
- **Production code: annotated at the declarations.** Covers
`tools/Opc.Ua.SourceGeneration.Core`, `src/Opc.Ua.Lds.Server` and the
LDS sample.
- Members, parameters and returns are nullable where null actually
flows.
- Null-check helpers carry `[NotNullWhen]` (`IsNull`, `IsValidXmlName`,
`IsMethodTypeDesign`).
- `CoreUtils.Format`, `Utils.Format`, `ITemplateWriter.WriteLine` take
`params object?[]`. `Template.AddReplacement` takes `string?` (rendering
already skips null replacements).
- `IRegisteredServerStore.RegisterAsync` returns
`Task<RegistrationEntry?>`: it returns null when a registration is
removed.
- Dereferences backed by an invariant (for example, the validated model)
use `!`, so runtime behaviour is unchanged.
- **Behavioural changes in production code** (small, deliberate):
- `NodeSetToModelDesign` throws `InvalidOperationException` when the
file is not a NodeSet. Before, it threw a NullReferenceException on the
next line.
- `ModelDesignValidator` starts its lookup tables empty instead of null.
A redundant `if (m_nodes == null) return;` guard is gone.
- **Test code: minimal annotations.**
  - `?` on values that can be null, `!` where the test asserts non-null.
  - `= null!` for fixture members assigned in SetUp.
- `TryGetStructure<T>(out T? x)` where the inferred `T?` broke the
`IEncodeable` constraint.
- A few redundant `== null` checks on structs (`NodeId`, `ArrayOf<T>`)
folded into the adjacent `IsNull`/`Count` checks.

**Notes for reviewers**
- The diff is large (~1,500 files) but almost entirely mechanical: `?`,
`!` and directive removal. The non-annotation changes are listed above.
- Known follow-up, not done here:
`IModelDesign.Namespaces/TargetNamespace/NamespaceUris` stay
non-nullable even though the validator returns null before it loads a
dictionary. Making them nullable would ripple through every generator
call site.

## Related Issues

- Fixes #4439

## Checklist

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [ ] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

The "no new warnings" box covers net10.0 and net48: full non-incremental
builds of `UA.slnx`, `tools/SourceGeneration.slnx`,
`tools/MigrationAnalyzer.slnx` and the Aot test projects finished with 0
warnings and 0 errors under the repository's warnings-as-errors
settings. net9.0 and net8.0 also had no nullable diagnostics, but they
were not rebuilt after the final fixes. Tests have not been run locally
yet.

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-08 08:48:13 +02:00
romanett 5572107ab8 Push Model compliance: UpdateCertificate issuer check, TrustList audit events, NoConfiguration state, DefaultHttpsGroup (#4684)
# Description

Fixes found by a manual run of the OPC 10000-12 *Push Model for Global
Certificate and TrustList Management* test plan (183 test cases,
TC0–TC182) against the Reference Server. After these changes no test
case fails; the remaining non-pass verdicts are test-plan expectations
that contradict Part 12/Part 4/Part 20 (documented in the run report).

### Server behaviour changes

- **UpdateCertificate requires the issuer in the TrustList**
(`ConfigurationNodeManager.PushValidation.cs`). The validator classifies
an incomplete chain as suppressible; OPC 10000-4 Table 100 does not ("An
error during the chain creation may not be suppressed") and §7.10.5
requires the issuers to already be in the group's TrustList. A
certificate of an unknown CA is now rejected with
`Bad_CertificateChainIncomplete`. Expiry / host-name errors stay ignored
as §7.10.5 requires.
- **TrustList audit events reach the Server Object.**
`TrustListUpdateRequested`/`TrustListUpdated` were reported on the
TrustList node (`EventNotifier=0`, not linked to the Server), so no
client could receive them. `TrustList.SetAuditEventServer` routes them
through `IAuditEventServer`; wired for the Push TrustLists and the GDS
CertificateGroup TrustLists. New `AuditEvents` overloads keep the
node-based ones.
- **Duplicate AddCertificate** no longer makes the following
ApplyChanges fail with a bare `Bad` (store refused the second copy); the
commit is idempotent and its rollback keeps the pre-existing
certificate.
- **CloseAndUpdate validates CRLs** (incl. CRL-only updates): every CRL
must be signed by a CA of the new TrustList (§7.8.2.5). Previously an
unknown/forged CRL passed CloseAndUpdate and only failed ApplyChanges.
- **X.509 v1 certificates are rejected** by
CloseAndUpdate/AddCertificate/UpdateCertificate (OPC 10000-6 §6.2.2; new
`X509Utils.IsX509Version3`).
- **Application setup state (Annex G.2):** new
`StandardServer.StartupServerState` (virtual); the DI host returns
`NoConfiguration` when `ServerConfigurationOptions.InApplicationSetup ==
true`. `IsRunning` and `NodeManagerLifecycle` treat `NoConfiguration` as
operational. The Reference Server `--provision` mode starts in
`NoConfiguration` and exposes `InApplicationSetup=TRUE`.
- **DefaultHttpsGroup:** the group is only created when Https stores are
configured — the Reference Server config had none, so its
`opc.https`/`opc.wss` endpoints used the RSA application certificate
with an empty TLS trust list and the Https certificate could not be
pushed. The sample config now declares
`HttpsIssuerCertificates`/`TrustedHttpsCertificates` and an
`HttpsCertificateType` certificate (new `CertificateTypeString` value
`Https`). An Https certificate is assigned to DefaultHttpsGroup only (no
longer also listed in DefaultApplicationGroup). Fixed
`AddSecurityConfigurationHttpsStore`, which built the trusted Https
store path from the store *type*.
- Minor: AddCertificate logs a warning when it adds a CA without a CRL
while `RejectUnknownRevocationStatus` is enabled; UpdateCertificate
refused for an insufficient SecureChannel raises
`CertificateUpdateRequestedAuditEvent` with Status=false.

### Kept on purpose
- PEM certificates are accepted (converted to DER).
- `Bad_NotWritable` when opening an already open TrustList (OPC 10000-20
§4.2.2) and for AddCertificate while a read handle is open (§7.8.2.6).
- No validation rules for DefaultUserTokenGroup / DefaultHttpsGroup
TrustLists (Part 12 defines them only for ApplicationCertificateType
groups).

### Notes for reviewers
- Existing tests in `ConfigurationNodeManagerPushTests` and
`PushCertificateRequestRegressionTests` signed pushed certificates with
CAs that were not in the TrustList; they now trust their CA first
(behaviour change above).
- Adding the Https certificate to
`Quickstarts.ReferenceServer.Config.xml` gives the Reference Server's
opc.https/opc.wss endpoints their own TLS certificate.

### Tests
-
`tests/Opc.Ua.Server.Tests/Configuration/PushComplianceRegressionTests.cs`
— duplicate add/rollback, PEM, v1/v3, CRL issuer/forged/CRL-only, audit
routing.
- `tests/Opc.Ua.Server.Tests/ApplicationSetupServerStateTests.cs` —
NoConfiguration startup state.
- `tests/Opc.Ua.Gds.Tests/PushComplianceTests.cs` — end-to-end over a
secure channel: TrustList transaction lifecycle, open-handle rules,
masked reads, duplicate/PEM add, unknown CRL issuer, unknown certificate
issuer, cross-Session CSR key, nonce rules, RemoveCertificate chain/CRL
handling. Mutation-checked: reverting the issuer, duplicate-add and CRL
fixes makes the corresponding tests fail.
- Additional cases in `PushCertificateRequestRegressionTests`,
`CertificateIdentifierTests`, `ApplicationConfigurationBuilderTests`.

Local runs (net10.0): Opc.Ua.Gds.Tests 1257 passed / 0 failed / 56
skipped; Opc.Ua.Server.Tests push/TrustList/audit/lifecycle subset 1209
passed; Core and Configuration test classes passed. net48 build of the
affected test projects succeeds; `dotnet format whitespace` clean.

## Related Issues

- None (findings from a manual Push Model compliance run).

## Checklist

- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [ ] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-06 18:48:02 +00:00
romanett 21e04bdba5 Make Bad_CertificateChainIncomplete unsuppressible; add UpdateCertificate renewal regression tests (#4683)
# Description

Follow-up to the master378 fix in #4678 (CTT: application certificate
renewal must use the configured trust stores). Master already ignores
the supplied `issuerCertificates` for the default application group (OPC
10000-12 §7.10.5), but it had no regression tests for CA-signed
renewals. While adding them I found a real gap:

**The validator treated `Bad_CertificateChainIncomplete` as
suppressible.** OPC 10000-4 Table 100 (Build Certificate Chain) says:
"An error during the chain creation may not be suppressed." §6.1.3 adds:
"Processing fails with Bad_SecurityChecksFailed if an element in the
chain cannot be found." UpdateCertificate for the application group
accepts every *suppressible* error (as §7.10.5 requires). As a result it
accepted a renewal signed by a CA that is **not** in the TrustList and
was only passed in the ignored issuer list, which is exactly what
§7.10.5 rules out.

## Changes
- `CertificateValidationCore`: remove `BadCertificateChainIncomplete`
from the suppressible status codes. An accept callback (`AcceptError`)
is no longer asked about it.
- `TrustList`: remove the local workaround that filtered out this error;
plain "accept suppressible errors" is now enough.
- Docs (`Certificates.md`, `CertificateManager.md`): drop it from the
suppressible list, and fix a sample that suppressed it.

## Tests
- `ConfigurationNodeManagerPushTests`:
- A CA-signed renewal with the CA installed succeeds with a missing,
empty, unrelated or malformed issuer list, and the trust stores stay
unchanged.
- A renewal whose CA is only supplied as an issuer is rejected with
`BadCertificateChainIncomplete`; stores and the current certificate are
untouched.
- End to end on an isolated server: a CA-signed renewal with no issuer
list is committed through ApplyChanges.
- `ConfigurationNodeManagerPushValidationTests`: the group TrustList
validator accepts a CA from the trusted or issuer store and rejects an
uninstalled CA.
- `CertificateValidationCoreTests` / `CertificateValidatorTest`:
- An incomplete chain is unsuppressible and never reaches the callback.
- A leaf trusted directly **stays valid when the peer supplies its CA**
(§6.1.3: chain certificates "may be provided with the application
Certificate").
- One existing test attached its approver only after validating, so it
never exercised suppression; it now validates with the approver
attached.
- Tests that only passed because of the bug
(`PushCertificateRequestRegressionTests`, the regenerated-key helper and
the rollback test) now install the signing CA in the TrustList first.

The two new rejection tests fail on master and pass with this change.

## Reviewer notes / behavior change
This was suppressible in 1.5.x as well. Application code whose accept
handler approved a CA-signed peer certificate without its CA (CA neither
installed nor sent by the peer) will now get a rejection. Without a
handler such certificates were already rejected, and the stack's own
handlers (`ApplicationInstance`, push validation) never accepted this
error. Worth a release note.

Local runs (net10.0), all passing:

| Suite | Passed | Failed |
|---|---|---|
| Server.Tests | 8310 | 0 |
| Core.Tests (security/transport filter) | 2039 | 0 |
| Security.Certificates.Tests | 358 | 0 |
| Core.Security.Tests | 558 | 0 |
| Client.Tests | 2761 | 0 |
| Gds.Tests (PushTest and TrustList tests) | 345 | 0 |

The net48 builds of Server.Tests and Core.Tests also succeed.

## Related Issues

- Related to #4678 (master378 counterpart)

## Checklist

- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [ ] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-06 18:14:17 +02:00
romanett 87122b5a24 Certificate validation: issuer store completes the chain but is no trust anchor (fix #4604 CTT regression) (#4653)
# Description

#4604 ("Trust leaf-only certificate chains from configured issuers")
made the issuer walk in
`CertificateValidationCore.GetIssuersAsync` set `isTrusted = true` for
every CA it resolved from the
**issuer** list (`TrustedIssuerCertificates`, `UserIssuerCertificates`,
`HttpsIssuerCertificates`). That turns the issuer
list into a trust anchor, so the server accepted:

- client application certificates issued by a CA that is only in
`pki/issuer`: CTT *Security General >
Security Certificate Validation 045* ("issued certificate of a CA that
is not trusted but available") expects
  `BadSecurityChecksFailed` on OpenSecureChannel and got `Good`;
- user X509 tokens issued by a CA that is only in `pki/issuerUser`: CTT
*Security User Token > Security User X509
014* expects `BadIdentityTokenRejected` on ActivateSession and got
`Good`.

Both passed in the CTT run of 2026-09-29 (before #4604) with the same
PKI and scripts.

## Spec reasoning

OPC 10000-4 §6.1.3 (Determining if a Certificate is trusted): a
certificate is trusted if it, or a CA
certificate in its chain, is in the **Trust List**. The **Issuer List**
only supplies CA certificates needed to
build the chain and is not a trust anchor. OPC 10000-12 (TrustList:
TrustedCertificates vs IssuerCertificates)
uses the same split. Before #4604 the stack followed this, and #4604
flipped the tests that pinned it
(`ExplicitIssuerChainAloneDoesNotEstablishTrustAsync`,
`VerifyMissingCRLNoTrustAsync`, the GDS
`X509TestUtils` issuer-only assertion).

## Interop trade-off

The scenario from #4600 is a peer that sends only its leaf certificate
while the receiver has the CA configured.
That case **still works** when the receiver trusts the CA, which is the
spec-compliant configuration:

- CA (root or intermediate) in the trusted store, the other CAs in the
issuer store or the trusted store: the issuer
walk completes the chain from the stores and the trusted CA makes it
trusted. No chain from the peer is needed.
- CAs only in the issuer store: rejected (`BadCertificateUntrusted` →
`BadSecurityChecksFailed` /
  `BadIdentityTokenRejected`).

To help the operators from #4600, the `BadCertificateUntrusted` result
now says, when the chain was built but
no CA in it is trusted, that issuer certificates only complete the chain
and that the CA has to be added to the
trusted certificates.

I did not add a configuration switch that makes the issuer list a trust
anchor. It would turn off a §6.1.3 check,
make every CA a GDS pushes as an issuer trusted, and need a new
`SecurityConfiguration` field. The comment on
#4600 also points at other causes (X509Store vs directory store
behaviour, `.cer` files ignored by the directory
store). Those are separate and unchanged here: the directory store has
read only `*.der`/`*.pem` since 1.5.378. If
an opt-in is still wanted, it can be added later as an explicit,
default-off `SecurityConfiguration` flag.

## Changes

- `CertificateValidationCore.GetIssuersAsync`: remove the `isTrusted =
true` for issuer-store CAs (the walk still
  continues, so a trusted CA further up still anchors the chain).
- Clearer `BadCertificateUntrusted` message when the chain was built
without a trusted CA.
- Restore the three tests #4604 flipped.
- New `LeafOnlyChainFromStoresIsTrustedOnlyByTrustedCaAsync` (directory
stores, leaf-only, Peers and Users):
root and/or intermediate trusted → `Good`; both only in the issuer store
→ `BadCertificateUntrusted`.

## Verification

- `Opc.Ua.Core.Tests` `Security` namespace (net10.0): 1024 passed, 0
failed, 8 skipped.
- CTT (isolated PKI, server without `-a`): compared with the 2026-10-03
run of master `efad0ddef` on the same PKI and unmodified scripts:
  - s01 user token: *Security User X509 014.js* Error → **Pass**
- s02 certificate validation: *Security Certificate Validation 045.js*
Error → **Pass**
- s03 cert management, s04 roles, s05 rest: no result changes. The only
differences in s01–s05 are
three CTT warnings ("ActivateSession ResponseHeader.Timestamp delay >
100 ms", first ActivateSession of a part).
- `Opc.Ua.Gds.Tests` `ClientTest` (net10.0): 106 passed. It uses the
restored `X509TestUtils` issuer-only assertion.
- `Opc.Ua.Core.Tests` builds for net48 with 0 warnings.

## Related Issues

- Fixes the CTT regression from #4604 (#4600).

## Checklist

- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-04 12:12:19 +00:00
romanett 61edaa1ed0 Remove netstandard2.1 and net472 target frameworks (#4624)
# Description

Drops support for **netstandard2.1** and **.NET Framework 4.7.2**.
Libraries now target `net48`, `net8.0`, `net9.0` and `net10.0`.
`Opc.Ua.Types` and `Opc.Ua.SourceGeneration.Core` still also target
`netstandard2.0`, but only because the Roslyn source generators load
them. There is no general netstandard2.0 support.

**Preprocessor directives** (112 files)
- Every `#if`/`#elif` mentioning `NETSTANDARD2_1*`, `NET472*`,
`NET_STANDARD_TESTS`, `SKIP_ECC_CERTIFICATE_REQUEST_SIGNING` or
`NETSTANDARD*` was evaluated against the remaining TFM set (net48,
net8/9/10, plus netstandard2.0 inside `Opc.Ua.Types`/`tools`) and
simplified. Dead branches were removed.
- Example: `NETSTANDARD2_1 || NET8_0_OR_GREATER` → `NET8_0_OR_GREATER`.
- Example: `NET8_0_OR_GREATER || NET472_OR_GREATER` → removed (always
true).
- Netstandard-only code was removed: `UnixFileModeShim`, the CRDT
reflection path in `ReplicatedGossipOptions.CreateReaderOptions`, and
the netstandard2.1-only test variants.

**Custom test logic**
- `targets.props` drops the `net472`, `netstandard2.0` and
`netstandard2.1` `CustomTestTarget` profiles, `NetStandardTests` and
`SKIP_ECC_CERTIFICATE_REQUEST_SIGNING`. Supported values are now
`net48`, `net8.0`, `net9.0`, `net10.0`.
- The `NET_STANDARD_TESTS` define is removed from 29 test projects.
- The "build netstandard shells as net10.0" overrides are removed from
18 projects.
- `RestrictForLegacyTfm` now only applies to `net48`.
- `tests/customtest.bat` is updated to the new values.

**Build / packaging / CI**
- MSBuild TFM conditions are simplified: Kestrel package choice, MQTTnet
v4 (net48 only), BouncyCastle, Di/OpenUsd/Vision/Stress test excludes,
and `System.IO.FileSystem.AccessControl` (dropped from Core).
- The MigrationAnalyzer nuspec drops its net472/netstandard2.1 lib
groups. The Azure signing lists are updated.
- `get-ci-matrix.ps1` removes the net472/netstandard test profiles
(including the PR-gating `linux-netstandard2.1`) and the matching build
legs.

**Breaking API change (2.0 preview):** removed
`HttpsTransportListener.IsWssTransportSupported` and
`ReplicatedGossipOptions.IsGossipStateDecodingSupported`. They only
returned `false` on netstandard2.1 and are now always `true`. The test
guards that used them were removed as well.

**Docs**
- NuGet READMEs, `README.md`, `DeveloperGuide.md`, `PubSub.md`, the
certificate/ECC/identity docs and the 2.0 migration guide (plus its
`.agents` skill mirror) are updated.
- The migration guide notes that 4.7.2 consumers must move to 4.8 and
netstandard2.1 consumers to net8.0+.

### Reviewer notes
- The `System.IO.FileSystem.AccessControl` `PackageVersion` pin is left
in `Directory.Packages.props`. It has no direct reference any more, but
transitive pinning is on, so it was kept to avoid shifting resolved
versions.
- The `#if` rewrite was done mechanically by a truth-table evaluator.
The diff in the `.cs` files is limited to directive lines, removed dead
branches, and stale-comment updates.

### Verified locally
- `dotnet build UA.slnx -p:CustomTestTarget=net48`: 0 errors.
- `dotnet build UA.slnx -p:CustomTestTarget=net10.0`: 0 errors.
- Default multi-target builds (no `CustomTestTarget`) of Opc.Ua.Types,
Bindings.Https, PubSub.Mqtt and Redundancy.Server succeeded.
- net10.0 tests:
  - Opc.Ua.Redundancy.Server.Tests: 840/840 passed.
  - Opc.Ua.Types.Tests: 11363 passed, 1 skipped.
  - ModelDependencyScanner tests: 20/20 passed.
- The full test suite was **not** run locally.

## Related Issues

- None

## Checklist

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [ ] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [ ] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-02 17:09:49 +02:00
romanett 920ebda69b Fix transport channel and encryption audit findings (#4626)
## Summary

Fixes the Critical, High and Medium findings of a read-only audit of the
low-level transport channels (UA-TCP / UASC, HTTPS, WSS, Kestrel TCP,
buffer management) and the encryption layer (key derivation, nonces,
RSA/ECC, EncryptedSecret, security policies). Every finding was traced
in source and checked against the specification (Parts 2, 4, 6, 7)
before fixing.

Scope: 2 Critical, 1 High, 21 Medium → **21 fixed, 3 partial**. Low
findings are not part of this PR.

### Critical / High

**T7-1: HTTPS session isolation (Critical).**
- **Affects:** servers that expose a secured `opc.https` endpoint.
- **Problem:** over HTTPS all clients share one SecureChannel (Part 6
7.4.1), so the session AuthenticationToken is the only thing that keeps
sessions apart. The spec therefore requires it to be at least 32 random
bytes. For secured channels the server issued tokens that are not hard
to predict.
- **Impact:** another client on the same HTTPS endpoint could act within
a session that does not belong to it, with that session's identity and
permissions.
- **Fix:** `SessionManager` now always issues a random 32-byte opaque
token, on every transport (Part 6 7.4.1, Part 4 7.35).

**T1-1: secured client channels could lose their protection
(Critical).**
- **Affects:** opc.tcp clients connecting to Sign or SignAndEncrypt
endpoints.
- **Problem:** the client did not verify that the OpenSecureChannel
response used the security policy and mode it had requested, as Part 4
5.6.2.1 and Part 6 6.7.4 require.
- **Impact:** an attacker in the network path could make a secured
channel continue without message security. The check on the server
signature in CreateSession limits this on first connect. The session
reconnect path has no equivalent check. Traffic of an existing session
could then lose confidentiality and integrity without the application
noticing. Other users of the channel (discovery, registration, custom
service clients) were not protected at all.
- **Fix:** a client channel for a secured endpoint is now bound to the
requested policy and mode. A response with any other policy or mode, or
without the server certificate, faults the channel, on connect and on
reconnect.

**T8-1: Kestrel opc.tcp listener availability (High).**
- **Affects:** servers using `KestrelTcpTransportListener`.
- **Problem:** the listener did not expire idle channels and did not
reclaim unused ones when it reached `MaxChannelCount`, unlike the
classic listener. Part 4 5.6.2.1 requires closing the oldest unused
channel without a session before refusing new ones.
- **Impact:** an unauthenticated peer could exhaust the channel slots
and deny service to legitimate clients.
- **Fix:** activity tracking, an inactivity sweep based on
ChannelLifetime, and reclaiming the least recently used channel without
a session at the limit.

**E2-1: user token decryption errors (Medium, High where lockout is
disabled).**
- **Problem:** the result of a failed user identity token decryption
could reveal more than Part 4 7.40.2.1 allows, which says every
decryption error must look like `Bad_IdentityTokenInvalid`.
- **Mitigation already in place:** the default failed-authentication
lockout limits how this can be used.
- **Fix:** clients now receive only `Bad_IdentityTokenInvalid`, with the
detail logged on the server. Token decryption takes the same steps
whichever check fails.

### Medium
- **Key derivation / sequence numbers:** E1-1/T2-1 renewal XORs the
previous secret only for SecureChannelEnhancements policies (Part 6
6.8.1 Step 2); T2-2 Sign-mode HKDF length uses enc key / IV length 0
(Part 6 6.8.1); T2-3 server chains a second renewal from the pending
renewed token like the client; T2-4 receiver rejects sequence-number
gaps (Part 2 5.1.14).
- **OPN / client channel:** T1-2 (partial) OPN sender certificate
checked against the policy's key family / curve and RSA key-length
window (Part 4 6.1.3, Part 6 6.1); T3-1 renewal completion no longer
blocks on a newer handshake while holding the gate; T3-9 reverse-connect
listener bounded (1000 pending, 500/s, burst 1000).
- **TCP listener / buffers:** T5-1 Basic128Rsa15 abuse tracker fails
open for untracked IPs when full; T5-2 refused connections get
`Bad_TcpNotEnoughResources` after the HEL (Part 6 7.1.2.3); T6-2
(partial) idle sockets no longer hold a receive buffer; T6-3
`AsyncResultBase` completes exactly once, reverse-connect timeout
cancels the connect.
- **HTTPS:** T7-3 chunked request bodies supported (Part 6 7.4.1); T7-4
mTLS CreateSession compares only the leaf certificate and answers a
mismatch with a ServiceFault; T7-5 (partial) opcua+openapi WSS path gets
the discovery-only gate; T7-6 default rate limiter partitioned per
client IP; T7-7 shared Kestrel host owns its TLS certificate and
rotation rebuilds it for all listeners.
- **WSS / Kestrel TCP:** T8-2 SecureChannel and certificate audit events
(Part 4 6.5.5); T8-3 queued senders fail with BadConnectionClosed on
close instead of hanging; T8-4 WSS clients keep the mTLS client
certificate alive; T8-5 WSS+JSON close bounded by timeout and
cancellation.

### Partial / not fixed
- T1-2: missing CertificateSignatureAlgorithm check per chain
certificate, issuer key length ≥ issued key length, and checks on ECC
issuers.
- T6-2: `BufferManagerMemoryLimiter` still blocks the calling thread
when real traffic exhausts the budget (needs an async TakeBuffer API).
- T7-5: the fallback to any SecurityMode=None endpoint stays, because
HTTPS listeners advertise `HttpsOpenApiTransport`.
- Not covered: the HTTPS listener's WSS uacp channels likely need the
same idle cleanup / reclaim as T8-1.
- Not covered: the certificate/policy key check (T1-2) applies to UASC
channels; the opc.https session path is a follow-up.

## Behaviour changes reviewers should look at

**Wire-incompatible with older versions of this SDK (both conform to the
spec now):**
1. Renewals on ECC_nistP256/P384, ECC_brainpoolP256r1/P384r1,
ECC_curve25519/448 no longer mix in the previous secret; a renewal
between this and an older SDK fails on the first message after renewal.
2. Sign-mode channels on those CBC+HMAC ECC policies derive different
keys; Sign-mode channels to older SDKs fail.

**Other:**
3. Every session AuthenticationToken is a 32-byte opaque ByteString
NodeId, on every transport.
4. Any sequence-number gap faults the channel with
`BadSequenceNumberInvalid` (client side previously reported
`BadSecurityChecksFailed`). Only a reconnect OpenSecureChannel may skip
ahead.
5. OPN peer certificates outside the policy's key-length window or with
the wrong key family/curve are rejected (e.g. 4096-bit RSA on Basic256 /
Basic128Rsa15).
6. Refused opc.tcp connections get an ERR after their Hello; a refused
socket can stay open up to 2 s waiting for it.
7. Kestrel opc.tcp listener closes idle channels and, at
MaxChannelCount, the oldest unused channel (BadNoCommunication) instead
of refusing the new client.
8. HTTPS mTLS CreateSession mismatch → ServiceFault
`Bad_SecurityChecksFailed` instead of HTTP 401; oversized HTTPS bodies →
413 instead of 500; default HTTPS rate limit is 100 req/s per client IP.
9. Certificate rotation on a shared (host, port) restarts the shared
Kestrel host once; TLS connections on that port reconnect.
10. `EncryptedSecret.TryDecrypt/TryDecryptAsync` return false on the RSA
branch instead of throwing (public API behaviour); `TryDecryptRsa`
reports `Bad_SecurityChecksFailed` for padding/layout/signature
failures. A KeyData whose encrypted length differs from what the policy
and receiver key imply is rejected the same way, before decryption.
11. Client reverse-connect listener limits pending connections and
connection rate; at its cap the oldest connection that has not sent a
ReverseHello is closed to make room. On opc.wss the cap applies only to
connections not yet handed off.
12. `ApplicationInstance` creates its own RSA application certificate
with at least 2048 bits (except the RsaMin type), even when
`MinimumCertificateKeySize` is lower; that setting only bounds accepted
peers.
13. Kestrel opc.tcp listener: `ChannelLifetime` <= 0 disables the idle
sweep; otherwise the sweep runs at most once per second.
14. Certificate rotation on a shared Kestrel host closes the listener's
WebSocket connections and outbound reverse-connect channels even when
the TLS certificate is unchanged; if the new host fails to start, a host
with the previous TLS certificate is restored and the error is rethrown.
Listeners on the same (host, port) share a Kestrel host only when their
host-level settings (mutual TLS, admission limits, middleware) match;
otherwise the listener uses its own host, as for a TLS certificate
mismatch.
15. On a second renewal before the first renewed token was used, the
server makes the first renewed token current (raising `TokenActivated`
then) instead of dropping it; a reconnect chains from the current token.
16. Sign-only HKDF channels report empty IV/key plus the signing key
length in channel diagnostics and the Wireshark keyset.
17. `UserNameIdentityTokenHandler.DecryptAsync` throws the specific
RSAEncryptedSecret failure; the server still answers clients with a
plain `Bad_IdentityTokenInvalid` and logs the cause.
18. Refused ReverseHello messages up to the maximum valid size also get
the `Bad_TcpNotEnoughResources` reply; `TcpByteTransport` rents receive
buffers at the chunk size.

## Tests

New regression tests for every Critical/High fix fail before the fix.
Tests that pinned old behaviour were updated:
`TcpReconnectKeyAgreementTests`,
`UaSCBinaryChannelSequenceRolloverTests`,
`TcpMessageFailureRegressionTests`,
`TcpTransportListenerDeterministicTests`.

Combined branch, net10.0:

| Suite | Passed | Skipped | Failed |
|---|---|---|---|
| Opc.Ua.Core.Tests | 6036 | 88 | 0 |
| Opc.Ua.Bindings.Https.WebApi.Tests | 405 | 0 | 0 |
| Opc.Ua.Server.Tests | 7806 | 5 | 0 |
| Opc.Ua.Client.Tests | 2733 | 0 | 0 |
| Opc.Ua.Gds.Tests | 1234 | 56 | 0 |
| Opc.Ua.Sessions.Tests | 790 | 379 | 0 |

net48 builds of the Core, Server, Client and WebApi test projects and
the netstandard2.1 Release build: 0 errors, no new warnings. One
telemetry test (`ActivityTraceFlags_Metrics_ShouldRecordMetricsOnly`)
failed once under parallel load and passes on rerun.

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-02 12:08:16 +02:00
Copilot c4e99c6e3a Trust leaf-only certificate chains from configured issuers (#4604)
# Description

Leaf-only peer certificates failed validation when their intermediate
and root CAs were configured in `TrustedIssuerCertificates`. The issuer
walk built the chain but did not treat those configured issuers as trust
anchors.

- **Validation**
  - Mark issuers resolved from `TrustedIssuerCertificates` as trusted.
- Preserve rejection of chains containing only peer-supplied,
unconfigured issuers.

- **Regression coverage**
- Update explicit issuer-chain validation for Peers, Users, and HTTPS
scopes.

## Related Issues

## Checklist

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [ ] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

<!-- START COPILOT CODING AGENT SUFFIX -->

- Fixes #4600

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: marcschier <11168470+marcschier@users.noreply.github.com>
2026-10-02 06:43:54 +02:00
romanett ce88955f70 Harden encoders/decoders against untrusted input and align them with Part 6 / Part 14 (#4599)
# Description

Hardens the encoders and decoders against untrusted input and aligns
them with OPC 10000-6 (1.05) and OPC 10000-14. This comes from an audit
of every codec reachable from a peer:
- Binary, JSON and XML decoders and encoders;
- built-in and complex types;
- UA-TCP/UASC framing;
- PubSub UADP and PubSub JSON.

The audit found 97 issues: 1 critical, 7 high, 39 medium and 50 low.
They are all fixed here, one commit per finding (IDs B1-, J1-, X1-, T1-,
S1-, U1-, P1-, E1-, E2- in the commit subjects). Every fix was then
checked against the spec a second time, and the deviations that re-check
found were fixed as well (`*-spec` commits).

## Security (decoders reachable from unauthenticated peers)

- **Allocation from length prefixes (B1-1, B1-5, U1-1, U1-3).**
- Array, string and byte-string lengths are checked against the bytes
left in the message before anything is allocated.
- Arrays read element by element grow as elements are decoded, so nested
length prefixes can no longer multiply memory.
- UADP discovery counts and chunk reassembly buffers are bounded the
same way.
- **Stack exhaustion.** Nesting is checked for remaining stack
(`RuntimeHelpers.EnsureSufficientExecutionStack` mapped to
`BadEncodingLimitsExceeded`), and the large Variant read/write methods
were split into scalar, array and matrix methods. Measured on 1 MB and
256 KB threads, no codec overflows at the default limits any more.
- **XML element depth (X1-1).** XmlElement values and raw
ExtensionObject bodies are copied node by node with a depth limit,
instead of with the recursive `InnerXml`, `ImportNode`, `InnerText` and
`DeepEquals` calls.
- **Limit bypasses:**
- JSON NodeId, QualifiedName and opaque strings now respect
MaxStringLength and MaxByteStringLength (J1-1).
  - Matrix rank is limited to 32.
  - Decimal size is bounded (T1-3).
  - XML base64 is checked before it is decoded.
  - XML arrays are checked before each element is read.
- **CPU and algorithmic cost:**
- UADP reassembly uses an O(1) overlap check with a per-message chunk
cap (U1-2).
  - PubSub JSON matches fields to metadata through a name index (P1-2).
  - LocalizedText "mul" text is parsed lazily (T1-5).
- Unknown SecurityTokenIds trigger a throttled background SKS refresh
instead of an inline call per datagram (U1-9).
- **PubSub metadata poisoning (P1-1).** Inbound metadata is registered
only for identities a configured reader expects, is capped, and an
unauthenticated message can no longer pin a version.
- **Exception contract.** Decoders fail with `ServiceResultException`
(BadDecodingError / BadEncodingLimitsExceeded) instead of letting
ArgumentException, InvalidOperationException, TypeLoadException and
similar escape.
- **UASC (S1-*):**
  - OPN and CLO must be single final chunks.
  - The certificate of an unsigned OPN is ignored.
  - The padding and ExtraPadding bytes are validated.
- A renewed token is activated only after a chunk has been verified with
it.
- A policy change on renewal is rejected before the channel certificate
is touched.
  - Secured chunk length arithmetic is bounded.

## Wire-visible behaviour changes

All follow the spec exactly; there is no reader for the old forms unless
noted.

- **UA Binary:**
  - Variant type ids 26-31 decode as ByteString.
- Picoseconds without their timestamp are ignored, and values of 10000
and above are clamped to 9999.
- A Null-type Variant with the array flag consumes its length and
dimensions.
- **UA JSON:**
- Messages are ExtensionObjects with the body inline; there is no
`UaBody` envelope any more (5.4.9 / 5.4.2.16).
- The Variant `Value` is omitted exactly for NULLs of nullable types
(Table 41).
  - RawData keeps nested UaType/UaTypeId and the StatusCode Symbol.
  - Duplicate member names are rejected.
  - `{}` decodes as a null ExtensionObject.
- Numbers and identifiers are parsed strictly and culture-independently.
  - QualifiedName follows 5.4.2.14.
  - Opaque bodies of known types carry the DataType id.
  - Enumerations without a literal are written as the number.
- **UA XML:**
  - The earliest DateTime is written as `0001-01-01T00:00:00Z`.
- Null typed scalars and null array elements are written with `xsi:nil`.
  - An ExtensionObject without a body has no `Body` element.
  - Strings XML cannot represent are rejected.
- Only the xs:dateTime and xs:date forms are accepted; a value without a
zone is still read as UTC, because published model files use it.
  - Only the Part 6 Guid form is accepted.
  - Booleans are case-sensitive in XmlDecoder.
- **UA-TCP:**
- OPNC/OPNA/CLOC/CLOA fault the channel. Older releases that split a
long-chain OPN into chunks are rejected, so this needs a release note.
  - The sender truncates the certificate chain to fit a single chunk.
  - The received certificate chain is sized from the chunk size.
- Hello buffer sizes down to 1024 bytes are honoured; below that, an ERR
with Bad_TcpInternalError is sent.
- A 4096-byte Error reason is accepted, and the SecurityPolicyUri limit
is 255 bytes.
- **PubSub UADP:**
- Chunk NetworkMessages use the Part 14 7.2.4.4.4 layout, and each chunk
is secured on its own with its own sequence number.
  - The Sizes array is part of the secured payload.
- Padded RawData keeps its length prefix, and null values are written as
-1.
  - DataSetMessages with the valid bit clear are skipped.
  - Null discovery arrays are accepted.
- **PubSub JSON:**
- Variants use `UaType`/`Value`, with the 7.2.5.4.2 top-level collapse.
The deprecated `Type`/`Body` form is still read.
- Status is written as a `{Code,Symbol}` object; a numeric Status is
still accepted.
  - Discovery messages follow Tables 188-192, with GUID MessageIds.
  - Enumeration fields are written as `Name_Value`.
  - Fields appended with a MinorVersion bump are accepted.

## Known deviations and limitations (documented, not changed)

- A known type whose ExtensionObject XML body fails to decode fails the
message, like a failing binary body. 5.2.2.15 only says the decoder
*should* continue, and continuing reopens the log-flooding path.
- Reserved Variant type ids 26-31 are passed to the application as
ByteString without the raw type id.
- JSON UaTypeId of an opaque body of an *unknown* type stays the
encoding id, because no type system is available to map it.
- PubSub JSON encoder:
- Structure fields without a subtype are still wrapped with a UaType,
and concrete multi-dimensional or abstract-rank fields still carry a
UaType (Table 186).
- Namespace-0 enumerations without EnumDataTypes are written as a
numeric string.
- Chunked transcoded frames have no writer group, so their sequence
numbers continue from the source number.
- Pre-existing and out of scope: the HTTPS JSON binding uses
Content-Type `application/opcua+uajson`, while 1.05 7.4.5 requires
`application/json`.

## Tests

- Every fix has a regression test.
- Tests that pinned non-conformant behaviour were updated, and their
commit messages say so.
- Fuzz seeds were regenerated where the wire changed.

Local results:
net10.0, 27 suites green (Types 11354, Core.Encoders 2933, Encoders.Fuzz
8112, Core 5955 + 1 known intermittent ActivityTraceFlags metrics test
that passes alone, Client 2732, Server 7802, Sessions 790, GDS 1234,
Subscriptions 641, SourceGeneration.Core 4266, PubSub 1490 and all
PubSub transport suites). Full UA.slnx build 0 warnings / 0 errors on
net10.0 and net48.

## Related Issues

- Follow-up: #4598 (possible throughput regression of per-element binary
array reads).

## Checklist

- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed. (net10.0
suites run; net48 build only)
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-01 05:12:47 +00:00
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
Marc Schier 46fa7d364a Harden recovery, concurrency, and resource lifetimes across the OPC UA stack (#4516)
# Description

Bound managed-session recovery, preserve Publish workers and recovery
ownership, and address the client, server, transport, and certificate
audit findings and subsequent concurrency review. Also reduce the memory
retained by exhaustive session-test diagnostics.

## Recovery and Publish ownership

- Add `ManagedSessionOptions.ChannelReconnectTimeout` through direct
construction, the fluent builder, and DI. The automatic duration is
`max(3 * KeepAliveInterval, revised SessionTimeout, OperationTimeout)`,
sampled at cycle start. Positive overrides are supported;
`Timeout.InfiniteTimeSpan` explicitly opts out. Raw sessions retain
their unlimited default.
- Add `CreateReconnectBudget(TimeProvider)` as a required
`IReconnectParticipant` member, as agreed in review. Custom participants
implement it and may return null for no participant-specific bound.
- Enforce the earliest participant/caller deadline through transport
reconnect, activation/recreation, and subscription restoration. Late
callers can shorten an active cycle but cannot extend it.
- Cancel and unwind recovery, fence late responses, and release channel
recovery ownership before the existing `Faulted` event hands control to
the outer reconnect/failover policy. Preserve session recreate admission
through final Publish cleanup and keepalive suppression until shared
recovery is complete.
- Treat participant budget creation/evaluation failures, including
exceptions at the exact deadline, as terminal shared-recovery failures.
Notify participants before exposing `Faulted`, preserve the original
diagnostic, and never silently replace a finite budget with unlimited
recovery.
- Keep caller-supplied replacement channels, managed bindings, wrapper
event subscriptions, and recovery-owner identities consistent across
success, failure, and cancellation. Reject replacement during active
recovery and fence retired callbacks so they cannot clear newer
ownership or suppress later keepalive recovery.
- Retain eligible Publish workers through temporary
subscription-identifier clearing without retaining workers for
never-created or removed subscriptions. Preserve cancellation,
acknowledgement rollback, and drain-before-replacement ordering.
- Coordinate automatic subscription updates with session recovery:
cancel admitted updates, keep them paused across a failed-restoration
handoff, and retry only after explicit restoration completes. This
prevents competing CreateSubscription requests and updates against a
retiring session, while preserving manual recreation, transfer fallback,
and pending option changes.
- Exercise the real ManagedSession, V2 subscription engine, and channel
ready gate with scripted transports and an injected clock. Cover
transfer fallback, deadline handoff, late completions, and resumed
notification delivery.

## Audit and review corrections

- Correct certificate/trust-list transactions, change-pump lifetimes,
validation, peer revalidation, and reset/resource ownership.
- Harden node admission, attribute/range/dimension validation,
monitored-item sampling and lifecycle transitions, event fanout, and
server shutdown. Run lifecycle readiness and compensation outside shared
monitored-item admission, with stale-completion ownership checks.
- Close synchronous node-manager admission before teardown and retain
resources until admitted service, lifecycle, and asynchronous method
work returns. Dispose the monitored-item manager outside both locks,
reject late calls before they can reach it, and forward asynchronous
disposal through the adapter so the master awaits the same completion.
Preserve reentrant shutdown initiation, cancellation/failure unwinding,
and shared cleanup-failure reporting.
- Bound WSS pending-request retention using connection-local wire
handles while preserving caller-visible request handles and translating
Cancel targets. Safely ignore retired replies and drain admitted
send/close users before resource disposal.
- Clarify that the shared `ClientBase` caller-handle sequence is
distinct from the non-wrapping WSS wire allocator. Existing
exhaustion/reopen, late-reply, and Cancel-translation regressions verify
the connection-local contract; no allocator behavior was changed by this
clarification.
- Preserve virtual-node validation and resolver service errors instead
of converting them to cached misses. A mismatched NodeId reports
`BadNodeIdInvalid`; callback type mismatches and resolver service errors
keep their exact status. Per-item boundaries preserve unaffected reads,
writes, history operations, method calls, browse paths, and
monitored-item creation/restoration, including permission-validation
paths. Caller cancellation still propagates; stored-item validation
failures are logged without aborting later restores.
- Correct client file/role/state-machine/streaming APIs, node-cache
behavior, redundancy/failover ownership, and session
configuration/identity handling.
- Cancel each owned peer-discovery scope before disposing it, including
when the bounded wait wins a cancellation-delivery race. Keep late
results out of the endpoint cache and preserve single-flight lookup
ownership.
- Keep materialized alias Browse results synchronized with the live
store by default, preserving explicit startup-only opt-out. Apply
HistoryUpdate service results per value while retaining explicit
all-or-nothing provider APIs.
- Update the directly related feature documentation and add focused
positive, negative, concurrency, and ownership regressions.

## Latest review-feedback corrections

- Fence stale failed lease observations with a successful-confirmation
generation distinct from the revocation epoch. Snapshot it before each
store read, including failed-CAS revalidation, so an old failure cannot
revoke or reschedule a newer lease while fresh ownership loss still
revokes leadership. Preserve independent overlapping acquisitions,
expiry, disposal, and late-success protections.
- Isolate attributable WSS response-decoding errors to their request,
including retired handles. Keep admitted socket sends connection-owned
so caller timeout/cancellation cannot abort sibling requests; shutdown
still cancels and drains those sends.
- Restart keepalive and classic Publish replenishment after successful
session reuse. Retire V2 worker demand after intentional
deletion/disable without confusing that state with temporary recovery
resets.
- Browse virtual directories lazily across continuation pages without
the 1,024-entry snapshot cap. Preserve active-page cancellation, bounded
metadata retention, pushback, and exactly-once asynchronous cursor
cleanup.
- Apply certificate/CRL staging in last-operation order, preflight
required issuer storage before writes, select actual policy-compatible
RSA keys for None endpoints, frame certificate chains independently of
signature OIDs, and preserve admitted validation results during
rejected-writer shutdown.
- Preserve base asynchronous disposal when a legacy override omits its
base call; avoid double derived disposal in the adapter. Let genuinely
admitted nested work finish while rejecting stale captured contexts and
returning null from closed lookup APIs.
- Re-park recovered monitored items if AddNodes rolls back. Give event
compensation a fresh finite deadline, and preserve healthy
Browse/Translate siblings at every reference/path boundary while
retaining starting-node errors and caller cancellation.
- Give final reconnect notifications a live, bounded shutdown-linked
lifetime. Synchronize child state before parent lifecycle handlers
outside the parent transition lock.
- Document the accepted existing policies: direct reverse connections
are single-use without a ReverseConnectManager, and multi-node stream
capacity is shared rather than reserved per node.

The expanded readiness controls also exposed a real generation-handoff
race: an old source could finish draining after activation was deferred
but before readiness tasks were collected, causing the wanted
replacement to be omitted from the wait set. A deterministic test gates
that exact interval; the fix keeps the replacement in the readiness
wait. The original race passed 200 repetitions after the fix. A separate
control now awaits both producer readiness and iterator entry under the
same original deadline, rather than treating those independent signals
as equivalent. Temporary logging and repetition are removed.

## CI integration contracts

The History and Server CI failures exposed integration tests that still
asserted the behavior intentionally changed by the audit fixes. A
Windows WoT negative test raced its caller deadline against upstream
retries. A subsequent Ubuntu Client failure exposed a real
automatic-update versus explicit-restoration race:

- History insertion collisions now verify exact per-value statuses and
all persisted timestamps/values, including preservation of the existing
conflicting entry. Explicit atomic-provider rollback controls remain.
- Alias materialization tests wait for actual publication and verify the
added node plus forward/inverse `AliasFor` references, instead of racing
a startup-only snapshot expectation. Explicit refresh opt-out controls
remain.
- The unavailable-upstream WoT test uses an explicit finite retry policy
through existing DI configuration, preserving its original four-minute
guard and requiring a mapped-value service error before caller
cancellation. Production retry defaults remain unchanged.
- The Client fix retains the exact one-create and late-response
assertions. Three deterministic real-subscription/real-manager cases
cover paused creation, disposal while paused, and cancellation of an
admitted create followed by explicit restoration and a pending option
update. Both composed restoration-deadline cases also prove automatic
updates stay blocked at the outer handoff and resume after restoration.
- The merged-head net48 correction prevents lost peer-resolver
cancellation and distinguishes the harness's delayed initial `Connected`
event from actual outer recovery completion. A deterministic timer-order
test covers both cooperative and cancellation-ignoring resolvers,
cancellation before return, rejection of late cached results, and a
fresh subsequent lookup.
- The remaining CodeQL alert was a false content flow through
`ArrayOf.Count` into an integer-only trust-list summary. Projecting the
same count through `Span.Length` keeps cardinality distinct from
serialized contents without allocating, dropping diagnostics,
suppressing the rule, or dismissing the alert. Five log-contract cases
cover null/empty/nonempty results and mixed chain-capable/fallback
listeners, asserting the exact count, message, and structured
properties.
- Classic transfer acknowledges messages selected for asynchronous
Republish only after their responses arrive. The existing locked
replay-selection decision returns the immediate-acknowledgement subset
to Session, preserving the public transfer API, advertised availability,
and immediate acknowledgement of older gapped messages not selected for
replay. A callback changing `RepublishAfterTransfer` cannot change the
already-selected acknowledgement ownership.
- Transfer integration tests explicitly control acknowledged versus
retained origin messages. Exact assertions distinguish retained replay
from requested fresh initial values by sequence number, client handles,
values, status, and source timestamp. Atomic counters, observed
delivery/keepalive progress, and failure-safe session/file cleanup
replace timing assumptions and racy resets.
- Server lifecycle tests verify the documented independent five-second
compensation deadline rather than requiring a non-cancellable token.
They cancel the actual request, prove compensation and unrelated
monitored-item creation still proceed one tick before the deadline,
preserve the original failure and ownership assertions, and verify the
completed deadline is retired.
- Synchronous and asynchronous directory-browser tests require the exact
provider exception instead of an empty-directory success, then verify
the failed cursor is not enumerated again. These correct expectations
left behind by the intentional, documented provider-error propagation
change; production behavior is unchanged.

No tests were disabled, assertions loosened, coverage thresholds
lowered, or CI checks made optional. Existing platform exclusions and
Explicit debug variants remain.

## Related Issues

- Fixes #4514
- Fixes #4515
- Builds on merged #4503 and retains the #4508 publishing-drain
behavior.

## Validation

**Lease-election review correction
(`a13afa641182c70983e16bbcfebf507e666a45a5`):**

The correction is based on the existing upstream merge
`43079e2b851fe338a4082066f8d14abfdafb6e32`. Three deterministic
stale-verdict
cases fail on the original source and pass with separate confirmation
fencing.
Six new cases cover the initial foreign-owner verdict, failed-CAS
revalidation
in both invocation orders, and fresh ownership loss through both read
paths,
including revalidation begun after another successful confirmation.

| Target and configuration | Passed | Failed | Skipped |
| --- | ---: | ---: | ---: |
| net10.0 Debug | 120 | 0 | 0 |
| net48 Debug | 120 | 0 | 0 |

The selection is the full `Opc.Ua.Core.Tests.Redundancy` namespace,
including
all 38 `SharedStoreLeaseElectionTests` cases and the existing expiry,
clock
rollback, disposal, and overlapping-success regressions. New witnesses
are
`StaleForeignLeaseReadDoesNotRevokeNewerAcquisitionAsync`,
`StaleFailedRevalidationDoesNotRevokeNewerAcquisitionAsync`, and
`FreshForeignLeaseObservationRevokesLeadershipAsync`. They assert
resulting
leadership, exact transitions, independent progress, and the unchanged
expiry
boundary. Retaining the initial generation for the fallback read
independently
makes the fresh-loss-after-confirmation control fail; that mutation was
removed
before the final rebuilt runs.

The successful scoped command is
`dotnet test tests\Opc.Ua.Core.Tests\Opc.Ua.Core.Tests.csproj -c Debug
--no-restore --filter
"FullyQualifiedName~Opc.Ua.Core.Tests.Redundancy"`,
with `CustomTestTarget` and `-f` matching each row and that framework's
assets
restored. Both changed C# files pass formatting and analyzers through
informational severity on both frameworks. These are scoped results, not
a
full-solution test or measured coverage-delta claim. CI monitoring is
paused
for this feedback-only operation; no current-head CI success is claimed.

**Latest CI contract correction
(`1cd1f2047bb5b50c9bf300b1ff710b0b2e935a29`):**

All four failing Server shard 23 jobs in
[run
36120946740](https://github.com/OPCFoundation/UA-.NETStandard/actions/runs/36120946740)
reported the same six cases. Two local replays reproduced all six
failures.
The source changes and documentation from `cd43b831a` establish both
intentional
contracts: independent bounded event compensation and surfaced provider
errors.
Only the two test files are corrected; production code and CI policy are
unchanged.

| Target and configuration | Passed | Failed | Skipped |
| --- | ---: | ---: | ---: |
| net48 Debug | 113 | 0 | 0 |
| net10.0 Release, CI Coverlet settings | 113 | 0 | 0 |

The selection contains `MonitoredItemManagerLifecycleTests`,
`DirectoryObjectStateTests`, `DirectoryBrowserBoundedEnumerationTests`,
and

`EventCompensationReadinessHasFiniteDeadlineWithInfiniteSourceTimeoutAsync`.
Both changed files pass formatting and analyzers through informational
severity
on both frameworks. Independent mutations restoring a non-cancellable
compensation token and swallowing provider errors fail all four
lifecycle
cases and both browser cases, respectively. Both mutations were removed
before
the final passing runs and commit.

The scoped command is `dotnet test
tests\Opc.Ua.Server.Tests\Opc.Ua.Server.Tests.csproj`
with `CustomTestTarget` and `-f` set to the selected framework,
`--no-restore`, and
`--filter
"FullyQualifiedName~MonitoredItemManagerLifecycleTests|FullyQualifiedName~DirectoryObjectStateTests|FullyQualifiedName~DirectoryBrowserBoundedEnumerationTests|FullyQualifiedName~EventCompensationReadinessHasFiniteDeadlineWithInfiniteSourceTimeoutAsync"`.
The modern run additionally uses `-c Release /p:CollectCoverage=true
--collect "XPlat Code Coverage" --settings
tests\coverlet.runsettings.xml`.
These are scoped results, not a full-solution test or measured
coverage-delta claim.
Hosted checks for that commit were pending at publication. The fail-fast
CI
watch was stopped when the requested operation switched to review
feedback;
no current-head CI success is claimed.

**Earlier master merge (`8b15ea6ef9fc2214ac8ec886f373bb3846dd6d6f`, base
`b4136d8e9bab0df680f41d9ef985f519160534b1`):**

The `TcpListenerChannel` conflict preserves both lifetime
responsibilities:
disposal clears the retained peer-certificate chain and unregisters the
quota-scoped message-assembly scheduler. Both fields and all upstream
deadline
handling remain intact. The only additional manual source adjustment
adds the
parentheses required by the existing analyzer around the session-count
fallback.

Master advanced during validation. The initial transport merge
`80303c434ce813cf75aa7fe54a6a32fe2aeafc30` was retained, and the newer
base was
merged normally in `8b15ea6ef9fc2214ac8ec886f373bb3846dd6d6f`, without
rewriting
history. The additional recovery, fluent-pipeline, and test-framework
overlaps
were inspected; the branch's cancellation, validation-error, and
acknowledgement
ownership fixes remain alongside the upstream changes.

Full `UA.slnx` builds passed on net10.0 and net48 with **0 warnings and
0 errors**.
The final scoped tests rebuilt against the committed tree
`2074f8efcb61d8d9c6106e7d6f76ee941940e358`:

| Target | Passed | Failed | Skipped |
| --- | ---: | ---: | ---: |
| net10.0 | 2,653 | 0 | 0 |
| net48 | 2,529 | 0 | 7 |

The net48 skips are existing platform exclusions: six RSA_DH_AesGcm
nonce cases
and one ClientWebSocket certificate-validation case requiring .NET 7 or
later.
The selection covers transport cleanup, reassembly
budgets/deadlines/admission,
peer-chain ownership, server session binding, fluent lifecycles and
source
generation, reconnect and keepalive, transfer acknowledgements, Publish
queues,
and JSON encoding. Modern-.NET WSS transport and real-server integration
cases
also pass. The resolved file passed solution-relative formatting and
analyzer
verification through informational severity on both frameworks.

These are scoped test results, not unfiltered full-suite or
measured-coverage
claims. Hosted CI was not monitored or repaired as part of this
merge-only
operation.

Selected local results below are overlapping validation runs, not
distinct-test totals.

**Earlier review-feedback batch
(`cd43b831a8f11de3f7d65c3681712a61e3c669a5`):**
The final net10.0 scoped selection passed **471 tests, with no failures
or skips**.
The final net48 solution-root selection passed **439 tests, with no
failures and
one unchanged platform skip**
(`ValidateServerCertificateFallsBackToTlsPolicyErrors`,
which requires newer ClientWebSocket certificate-validation support).
Both full nonincremental solution builds completed with **0 warnings and
0 errors**,
and all **40 changed C# files** passed informational-level
formatting/analyzer
verification. Both frameworks validated the identical final tracked
diff.
The focused matrix covers every one of the 20 current review threads,
including
real mid-frame WSS cancellation, stale admission contexts, directory
continuation
ownership, multi-element Browse/Translate failures, and the readiness
drain race.
The net10.0 solution-root test command has a separate pre-existing
runner conflict:
three unrelated AOT projects reject the VSTest target under
Microsoft.Testing.Platform
2.4.0 and SDK 10. Per-project net10.0 results are recorded separately;
no runner
migration, test exclusion, assertion relaxation, or CI-policy change is
included.
These are bounded selections, not unfiltered full-suite or measured
coverage claims.
At publication of `cd43b831a`, hosted CI was not green: the
`OPCFoundation.UA-.NETStandard` check reported `ACTION_REQUIRED`,
AppVeyor reported
`FAILURE`, and the two signed-build jobs were in progress. No CI jobs
were rerun,
cancelled, approved, or repaired as part of that feedback-only
operation.

**Classic transfer correction
(`f425376fca045794122e19aaf9cafebc4a717d91`):**
The preceding head's
[macOS net10.0 shard
25/30](https://github.com/OPCFoundation/UA-.NETStandard/actions/runs/35980326299/job/107570512458)
failed
`TransferSubscriptionTest(DisconnectedRepublish).TransferSubscriptionAsync(True,False)`
at the static-node count assertion: expected 10, received 20. The trace
contains a successful,
explicitly requested republish of retained sequence 1 and a fresh
initial-value batch at sequence 3,
not duplicate dispatch of one response.

Controlled lost origin acknowledgements reproduced that incorrect test
expectation on both the
preceding PR head and exact master base
`a2539cb53dd1666cef856f33812d7a8830d68909`.
The maintainer explicitly authorized correcting this existing issue in
the PR. Retained replay
and requested initial values are independent, as specified by
[OPC UA Part 4,
TransferSubscriptions](https://reference.opcfoundation.org/specs/OPC-10000-4/5.14.7).
The reason that the original hosted run retained its particular origin
message remains unproved.

The expanded full-suite run then exposed a **real production race**, not
just a count assertion:
Session queued acknowledgements for all transferred available messages
before the asynchronous
Republish responses arrived. Publish could delete those messages first,
causing
`BadMessageNotAvailable`. A gated real-Session/classic-engine regression
failed both replay-enabled
cases on the original implementation while both no-replay controls
passed. The ownership fix
passes all 24 combinations of empty/consecutive/unsorted-gapped queues,
replay preference,
sequential delivery, and a reentrant preference change.

All 40 normal real-server transfer cases pass on both frameworks.
Independent mutations
suppressing actual replay and duplicating observed sequence records each
fail the intended
assertion; both mutations were removed. The full classic suite passes on
both frameworks.
Hosted CI was pending when that correction was published; the earlier
failed hosted job was not
rerun for a lucky pass.

**Local net48 caveat:** the full Client run timed out in the
pre-existing fake-clock test
`ReconnectAsyncSwapsFaultedLeaseEntryAsync`, which does not exercise
subscription transfer.
Its unchanged isolated replay passed, but that does not resolve the
full-suite timeout.
No unrelated code or assertions were changed, and a clean full Client
net48 run is not claimed.

| Scope | net10.0 | net48 |
| --- | --- | --- |
| Full Client.Tests after transfer acknowledgement correction | 2,549
passed | 2,552 passed, 1 timeout failure noted above, 1 existing
platform skip |
| Full classic-subscription project after transfer correction | 57
passed, including all 40 normal transfer cases | 57 passed, including
all 40 normal transfer cases |
| Gated transferred-message acknowledgement ownership | 24 passed,
included above | 24 passed, included above |
| Saved-session consumer of the shared subscription helper | 40 passed |
16 passed, 24 existing unsupported-security-policy skips |
| Audit regression matrix | 2,339 passed | 1,934 passed, 34 existing
skips |
| Full Client.Tests after review follow-ups | 2,520 passed | Focused
selections only |
| Full Client.Tests after CI recovery correction | 2,523 passed, CI
coverage collector | 2,527 passed, 1 existing platform skip |
| Latest merged-head recovery/redundancy selection | 139 passed | 139
passed |
| Full Client.Tests after merged-head net48 correction | Focused
selection above | 2,529 passed, 1 existing platform skip |
| Lifecycle and actual-dimension regressions | 146 passed | 146 passed |
| Focused recovery follow-ups | 7 passed | 7 passed |
| WSS-related fixtures | 93 passed | Not applicable |
| CI History integration corrections | 28 passed | 28 passed |
| CI alias, dispatcher, and explicit-atomic controls | 63 passed | 63
passed |
| Full WoT sample project with CI coverage collector | 29 passed | Not
applicable |
| Trust-list effects and count-only summary contract | 22 passed | 22
passed |
| Virtual-node feedback, node-manager, dispatcher, and lifecycle
selections | 661 passed, 63 existing not-executed cases; all 48
virtual-node cases passed | 661 passed, 63 existing not-executed cases;
all 48 virtual-node cases passed |
| WSS wire-handle exhaustion, late replies, and Cancel translation | 9
passed | Not applicable |
| Synchronous node-manager disposal and related service/lifecycle suites
| 1,037 passed, 64 not-executed cases from existing fixture assumptions;
all 93 sampling/disposal cases passed | 1,037 passed, 64 not-executed
cases from existing fixture assumptions; all 93 sampling/disposal cases
passed |

- Full solution builds passed on net10.0 and net48 during the audit
work. The subsequent full non-incremental net10.0 build also completed
with zero warnings/errors.
- Modified source/test formatting and analyzer checks passed through
informational severity.
- Original composed recovery regressions passed repeated runs on both
frameworks. Independent mutations removing Publish cancellation,
bypassing the recreate drain call, or ignoring ready-gate cancellation
each failed the intended assertion; all mutations were restored before
passing runs.
- The latest recovery correction passed 100 executions of each original
restoration-deadline scenario with unchanged assertions. Restoring
premature update admission independently made both strengthened handoff
cases fail; the correct retention behavior was restored afterward.
- Startup-event and cancellation-delivery timing probes reproduced the
subsequent net48 failures, then passed 100 executions of each of the
three scenarios with the fixes. All timing probes and repetition were
removed. The permanent timeout-order regression also went RED on the
original cancellation cleanup without sleeps or scheduling
amplification.
- Final post-format recovery/subscription/engine checks passed all 151
selected cases on net10.0. The first local full net48 attempt aborted in
`clr.dll` with native access violation `0xc0000005`; an
unchanged-assembly full diagnostic rerun passed as recorded above. That
native host crash has not been attributed or claimed fixed.
- A minimal replay with the same CodeQL CLI and query-pack versions
reproduced the custom-count alert and confirmed that the standard
span-length projection is clean while direct sensitive-value and
raw-identifier logging controls remain flagged. The source was already
logging only a count; no identifier or certificate disclosure was
established at the reported location.
- The virtual-node feedback regressions first reproduced five
error-preservation/cache failures; expanded service-dispatch cases
exposed two additional whole-batch failures before the
operation-boundary fixes. The final selections pass on both frameworks.
Genuine misses remain cached, successful results remain reusable, failed
validation allows same-cache retry, and request cancellation still stops
the batch.
- Three deterministic synchronous-manager disposal regressions
reproduced early resource release and lifecycle calls reaching a manager
during disposal. The fix passes direct and adapted calls, a
sampling-worker join after the last operation exits, reentrant shutdown,
cancellation and failure paths, repeated disposal, and exact rejection
across 39 service/lifecycle entry points both during drain and after
cleanup. The original outside-node-lock disposal regression remains and
now requires the worker to observe closed admission.
- Prior-head CI on `c985f8bded77a60449d9cd381c8a004d8590ccf6` completed
with **168 passing checks, one expected release-package-publication
skip, and no failures or pending checks**. All test shards, signed
builds, container builds, the coverage check, and the CodeQL PR check
passed. Hosted CodeQL analysis `1829262912` completed successfully and
marks count-flow alert 385 fixed. This is evidence for that head, not a
claim that subsequent review follow-ups have completed hosted CI.

### Session-test diagnostic memory

Complete browse listings are streamed to unique NUnit attachments rather
than retained in inline NUnit/VSTest output. Detached regression-test
results are cleaned up without deleting runner-collected attachments.

- Two covered session-suite runs each completed with 782 passed and 379
existing skips. Peak working set fell from 4.86 GiB to 2.44-2.78 GiB.
- TRX output shrank from 303.1 MiB to approximately 40.7 MiB, retaining
all 46 complete browse attachments.
- Seven output regressions cover exact content, empty/single/large
listings, disabled/enabled output, bounded inline summaries, and unique
filenames.

The separate Azure build-18452 VM deprovisioning cause remains unproved
without provider logs. The memory measurements do not establish its
cause.

Unfiltered local `UA.slnx` tests, including the long stress/soak suites,
have not been run on both frameworks. A local coverage delta was not
collected; builds and focused tests are not substitutes for those
claims.

## Checklist

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [ ] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] All checks on the latest review-follow-up head have completed
successfully; prior-head CI passed as recorded above.
- [x] I have addressed **all** PR feedback received.

Tests have been added and pass as recorded above; the hosted coverage
check passed on the prior head identified above. The combined
tests/coverage-increase checkbox remains open because no local coverage
delta was measured.

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: 68f26810-22b8-476f-abcd-0a8c82d6e208
2026-09-25 14:59:34 +00:00
Cristi Pogacean 5fa272d89a Fix instance-scoped certificate store resolution and consumers (#4546)
## Summary
Route certificate operations through the providers registered on the
configured manager, so custom stores work consistently during
validation, key loading, provisioning and GDS operations.

- Add optional `ICertificateStoreResolver`, implemented by
`CertificateManager`, without adding members to `ICertificateManager` or
removing existing public signatures.
- Use scoped resolution for configuration validation, startup and
cold-cache private-key lookup, application certificate
provisioning/reuse/deletion, existing-key GDS signing requests, and
hosted TrustList access.
- Preserve built-in lookup when no resolver is available, private-key
lookup fallbacks, access checks and transaction behavior. Resolver
failures do not silently fall back to Directory. Returned stores remain
caller-owned; TrustList retains cached-store disposal.
- Add regression coverage for instance isolation, mixed provider types,
real private-key reuse, rotation lookup, cancellation/failure disposal,
unavailable-key rejection, CSR output and TrustList lifetime. Document
the optional capability.

Fixes #4527
Fixes #4528
Fixes #4529
Fixes #4530
Fixes #4531

## Validation
Change-scoped Release tests on Windows, on base `5d26f6f43`:

| Fixture selection | net10.0 | net48 |
| --- | ---: | ---: |
| CertificateManagerFactoryTests + CertificateManagerTests | 71 passed |
71 passed |
| ApplicationInstanceTests | 56 passed | 56 passed |
| TrustListTests + ConfigurationNodeManagerPushTests | 147 passed | 147
passed |

All six selections exited 0 with zero failures or skips. Changed-file
whitespace verification and `git diff --check` passed.

Fresh no-fix comparisons retained the new resolver API/manager
implementation, but reversed the validation, provisioning and CSR
consumer fixes: validation had 2 custom-store failures / 1 built-in
control pass; provisioning had 4 custom-store failures / 1 built-in
control pass; CSR had 1 custom-store failure / 1 built-in control pass.
Failures reported unknown custom store types or invalid custom trust
stores. All consumer source changes were restored, rebuilt, and the full
focused net10.0 selections passed again.

Earlier TrustList regression evidence is recorded in #4531: its before
comparison retained the constructor injection boundary while exercising
the old store-opening path. It was not a test against an entirely
unextended API.

The complete platform/framework matrix is left to PR CI; no full local
matrix or completed CI qualification is claimed. Local restore used
command-line-only NuGet v2/feed-audit overrides; no repository feed,
test or contribution guidance was changed.
2026-09-25 12:13:31 +00:00
Marc Schier 138086863b Fix audit findings and review regressions across the OPC UA stack (#4503)
## Scope

Audit fixes and review follow-ups across the OPC UA Core, Client,
Server, transport, and redundancy components. This includes implemented
Tier 1, Tier 2, and Tier 3 work; it does not claim that every item in
the 244-finding audit backlog is complete.

The review batch fixes mandatory full-key record protection and owned
plaintext buffers; transactional pending-certificate claims;
shared-channel nonce and certificate ownership; discovery and
token-policy validation; reconnect/callback ordering without changing
unbounded buffering defaults; server permissions, filters,
monitored-item lifetime, and alarm topology; historian paging,
retention, and annotations; atomic user/password metadata; and canonical
file identities with bounded alias and role refresh workers.

## Review-batch verification at `ab686ccae`

The following results come from fresh test builds using `dotnet test`,
`--no-restore`, `-m:1`, and an explicit `CustomTestTarget`. They replace
the earlier description's library-build/`--no-build` totals, which did
not establish the state of the merged test sources.

| Scope | Target | Passed | Skipped |
|---|---|---:|---:|
| Core review regressions | net10.0 | 827 | 0 |
| Client and lifecycle regressions | net10.0 | 630 | 0 |
| Server review regressions | net10.0 | 1970 | 0 |
| Redundancy Server / Client / PubSub | net10.0 | 276 / 10 / 11 | 0 |
| Sessions / file-and-alias / streaming / HTTPS-WSS integration |
net10.0 | 8 / 21 / 30 / 20 | 0 |
| Core review regressions | net48 | 786 | 39 |
| Client recovery and policy regressions | net48 | 54 | 0 |
| Server ownership, aliases, queues, and user-state regressions | net48
| 137 | 0 |

Every listed run exited successfully. The 39 net48 skips are existing
platform/capability cases. New key-agreement tests assert
unavailable-policy behavior on unsupported targets rather than adding
skips or pretending those targets performed an unsupported handshake.
Additional exact node/permission/filter/alarm checks passed 13 Core and
46 Server cases.

The PR-scoped formatter verification covers 26 projects and 389
non-generated C# files. A Roslyn syntax audit covers 53 changed
interfaces and 263 members, with no missing
parameter/type-parameter/return contracts and a 120-column limit for
their declarations and documentation. No full-solution,
all-target-framework, or NativeAOT matrix is claimed from these local
runs; the new CI run must establish its own result.

## CI follow-up at `e1bc3ac3b`

The follow-up fixes the failures reported by Azure build 18400. TLS
certificates retain configured DNS names, including mixed-case URI
schemes, without relaxing hostname validation. Reverse-WSS fixtures use
the DNS identity in the client certificate. Reconnect completion is
published only after cycle cleanup, so a subsequent reconnect cannot
join an old completed cycle and retain old certificates.

Certificate-alarm roots now support event subscriptions. The pump sample
has one continuous notifier path, with no duplicate shortcut. Historian
and aggregate fixtures share the provider's retention clock. Alarm
collection lets the server expire idle Publish requests rather than
canceling only the client wait. The corrected server, WoT, and
managed-session fixtures exercise valid requests and initialized
lifecycle contracts. Downlevel crypto tests preserve real credential and
key-ownership assertions without enabling unsupported raw-ECDH policies
or adding skips.

Fresh local evidence after integration includes:

| Scope | Target | Passed | Skipped |
|---|---|---:|---:|
| Client lifecycle / channel ownership / builder fixtures | net10.0 and
net48, each | 96 / 103 / 123 | 0 |
| Combined server lifecycle, events, aggregates, crypto, and contracts |
net48 | 358 | 0 |
| Full lifecycle plus certificate-alarm and aggregate fixtures | net10.0
| 116 | 0 |
| Final server-contract and history-routing delta | net10.0 and net48,
each | 84 | 0 |
| Subscription / XRegistry / WoT event regressions | net10.0 | 7 / 2 / 3
| 0 |
| Full Sessions project | net10.0 | 780 | 379 |
| Full ComplexTypes project / downlevel resolver fixtures | net10.0 /
net48 | 2854 / 15 | 0 |
| Full WoT project / downlevel structured-write fixtures | net10.0 /
net48 | 1496 / 27 | 0 |
| TLS domain-name regressions | net10.0 and net48, each | 21 | 0 |

All listed runs exited 0. The Sessions skips come from existing endpoint
and policy capability guards; they are not counted as passes. No skip
was added. Worker validation also covered full DI (426 passes), full
History (540 passes, 21 existing skips), 38 exact downlevel
event/history failures, and 60 repeated certificate-rotation race cases.
The final crypto fixtures passed 73 cases on each target with the
unchanged leak detector; a temporary premature-disposal mutation made
all three borrower tests fail and was then removed.

All 29 C# files in this follow-up pass included-file formatting at info
severity across 12 projects. The complete PR interface audit now covers
54 interfaces and 271 members with zero missing contracts or line-width
findings. No full-solution or NativeAOT matrix is claimed. New-head CI
has started and remains authoritative for the remote result.

## Test-result gate follow-up at `4b6e1203a`

Azure build 18401 reported the net48 Client job as successful despite a
test-host crash after only 264 passing tests. Its old evaluator counted
per-test failures but ignored the failed run verdict. This was a partial
run, not a benign exit after the suite had completed.

The shared result evaluator now rejects aborted, errored, incomplete,
malformed, or inconsistent TRX reports. Each file must describe a
completed run, so a passing file cannot mask another file's failure. It
retains support for completed runs followed by a benign nonzero host
exit, existing skipped-result conventions, and no-TRX MTP jobs.

All 78 regression cases pass after integration using Windows PowerShell
5.1. Real completed Sessions and Client reports also pass. The
process-test fixture follows the existing NET10_0-only tools-test
pattern; its net48 build is not counted as a test run. Formatting passes
for the added test file.

The Client host crash itself has not reproduced locally. The isolated
fixture passed 59 tests, and two fresh full fast-CI selections each
completed with 2,392 passes and three existing skips, including a run
with crash collection enabled. The CI merge tree is identical to the
tested source tree. No speculative runtime change was made, and the
original partial CI run is not claimed as a full-suite pass. Azure build
18402 has now completed the full net48 Client run: 2,392 passed, three
existing console skips, and a successful test-host exit. The corrected
evaluator independently validated outcome=Completed. Across the matrix,
119 test-project jobs succeeded; Sessions net10.0 was canceled when the
remote provider deprovisioned its runner, so the overall Azure pipeline
was canceled. That cancellation is not claimed as a code failure or a
successful run. CodeQL and three Docker image jobs were still running at
the latest check. The migration discovery failure remains separate.

## Documentation follow-up at `57ed02bea`

The environment blocker has been removed by the maintainer. The three
bundled migration references now exactly match the canonical documents
after deterministic link rewriting; all 15 bundled documents pass
`validate-migration-plugin.ps1`. The canonical migration prose was not
rewritten. `FileSystemClient.md` now documents that extended Windows
roots preserve literal trailing-dot names, completing the filesystem
review follow-up.

The filesystem thread has been replied to and resolved after
publication. The review pass now has 108 of 110 threads resolved. The
two explanation-only threads remain open as requested; no unfinished
change request is being represented as resolved.

## Cross-platform follow-up at `0d9d936a8`

With migration discovery restored, the Linux and macOS test matrix
exposed two stale durable-subscription expectations. The expected value
83,442 encoded the old 32-bit overflow when converting 3,600 hours to
milliseconds. The existing overflow-safe server correctly returns
14,400,000 lifetime intervals at a 900 ms publishing interval. Only
those two expected constants changed; production behavior,
negotiated-hour checks, and all other assertions remain unchanged.

The exact local lifetime selection reproduced both failures before the
correction. The full durable suite now passes 36 cases with 11 existing
skips on each of net10.0 and net48. All four lifetime cases executed and
passed on both targets, and included-file info-severity formatting
passes.

## Session shutdown follow-up at `8daf7f091`

A late net48 Sessions failure exposed a shutdown race. Canceling an
in-flight keepalive read can produce a transport
`ServiceResultException`. The retiring worker treated its own
cancellation as proof that the peer was unavailable, so `CloseAsync` or
`DisposeAsync` could skip the server-side `CloseSession` request. The
worker now ignores that service error only when its own token is
canceled; genuine peer errors still update liveness.

The full integration fixture reproduced the original error-code
mismatch. Four deterministic mock-transport cases then produced three
failures and one passing genuine-error control before the fix. They
verify successful close, returned server error, asynchronous disposal,
and unchanged behavior for a real keepalive failure. Fresh related runs
pass 75 client and 101 integration cases on each of net48 and net10.0,
with no skips. Ten repetitions of the formerly flaky full net48 fixture
pass all 1,010 cases. All three changed files pass info-severity
formatting, and temporary diagnostic instrumentation was removed.

## Atomic listener snapshot follow-up at `82dc22b5d`

Ubuntu Core CI exposed an unsafe formatter rewrite in TCP listener
disposal: `ConcurrentDictionary.ToArray()` had become a collection
spread. A concurrent channel removal between the spread's count and copy
operations could leave a default entry, causing a null dereference
during disposal. The listener now uses the dictionary's atomic `Values`
snapshot and disposes those channels outside the listener lock.

Deterministic regressions close zero, one, or all channels at the copy
boundary. Before the fix, the one/all-removal cases reproduced the exact
null dereference; the unchanged-count control passed. All 23
admission/listener cases now pass on net10.0 and net48, and the full
fast Core net10.0 suite passes 5,267 cases with 88 existing platform
skips. Both changed files pass info-severity formatting. A bounded audit
of the formatter's other snapshot rewrites found no further verified
unsafe concurrent-registry copies.

## Shutdown-test observation follow-up at `58403ee8b`

The net48 shutdown-order test raced its own observation: it read
`m_publishWorkerTask` after starting shutdown, which can legitimately
drain the worker and clear that field immediately. The test now captures
the worker before shutdown starts and confirms it is initially running.
It still requires the worker to finish while shutdown remains blocked by
the held manager semaphore. Production behavior is unchanged.

A temporary scheduling perturbation reproduced the exact null-field
failure. The corrected capture passed 100 perturbed iterations; both the
temporary repeat and yield were then removed. The final 126
subscription/lifecycle cases pass on each of net48 and net10.0, and
formatting passes. A complete local Sessions net10.0 run also passed 780
cases with 379 existing capability skips in 7m20s after the earlier
keepalive correction.

## Retirement and alias-startup follow-up at `1a048ff39`

The shadow-generation test now observes its documented asynchronous
cleanup through the existing bounded helper. Removing the replacement
does not join a background drain that already claimed the retired
generation. The test still checks live-registration removal immediately
and requires the old node to disappear; no timeout or production
lifecycle behavior changed. All 81 lifecycle cases pass on each of
net10.0 and net48.

Initial alias-node materialization now retries one timed-out, read-only
snapshot query before creating nodes for that root. The retry is logged
through source-generated logging. Each query retains the original shared
100 ms deadline; repeated timeouts, other errors, and cancellation still
abort startup. Client searches and live refresh do not gain this
immediate retry. Fault-injection tests cover success after one timeout,
a persistent timeout, a different store failure, and cancellation. All
187 related alias/hosting cases and the original certificate-rotation
integration case pass on each target; the positive test records exactly
one retry warning. The alias documentation now accurately describes the
shared request budget.

All changed C# files pass formatter checks, and the complete
54-interface/271-member documentation audit passes. Fresh CI is running
on `1a048ff39`; the previous completed matrix exposed only the two
failures corrected in this batch and their dependent summaries.

## Sample endpoint allocation follow-up at `d08a94925`

The strong-cluster test harness allocated OPC UA and Raft endpoints in
separate released-port batches. Uniqueness was enforced only inside each
batch, so the same OS-assigned port could appear in both protocol
groups. The harness now requests one distinct batch for both groups and
splits it before launching any replicas.

Deterministic one- and three-replica allocation cases reproduced
overlapping groups with the old plan and pass with the corrected plan.
The complete 17-case short-haul sample suite passes without skips; all
failover, historian-continuation, and service assertions remain
unchanged. Both changed files pass info-severity formatting. This
prevents intra-cluster self-collisions but does not claim to reserve
released ports against unrelated external processes.

## Code-review follow-up at `085fd9636`

A review of the complete branch diff found five defects this PR
introduced. All are now fixed, each in its own commit.

`RelatedTo`'s recursive-to-iterative rewrite defaulted the optional
`includeTypeDefinitionSubtypes` and `includeReferenceTypeSubtypes`
operands to `false`. Part 4 §7.7.4 specifies both default to `true`, so
a filter that omitted them silently stopped matching subtypes.
Dynamically created key-credential nodes derived their namespace from
the containing folder, which is the standard `i=18155` node in namespace
0 — the namespace reserved for the OPC UA standard address space; they
now resolve the server-owned namespace and fail with `BadInternalError`
rather than guessing index 1. The retained audience-less
`CreateTokenData` overload produced tokens that verification always
rejects, so it is now `[Obsolete]` and throws instead. A failed
reference to a remote parent left the new node registered with a
one-sided inverse reference, and is now rolled back. An existing `.pfx`
is restricted before it is rewritten, rather than after its new key
bytes are on disk.

One further reported finding was rejected after investigation.
`JwksIssuerKeyResolver` deliberately does not dispose retired key
snapshots: `RetiredKeysAreCollectibleWhileResolverRemainsAliveAsync`
proves the resolver retains no retired snapshot, and
`ReturnedKeysSurviveRepeatedRefreshAndResolverDisposalAsync` requires
already-returned keys to keep verifying across refreshes and resolver
disposal. Adding disposal would have broken that tested contract, so the
exploratory change was reverted.

Validated on net10.0 and net48: 256 Core and 633 Server cases pass, with
one pre-existing net48 skip. The build reports zero compiler and
analyzer diagnostics, all eight included-file info-format checks pass,
the contract audit covers 58 interfaces and 310 members with no
findings, and the 15 bundled migration documents validate. All 122
review threads are resolved; the key-credential namespace thread was
reopened to retract an earlier incorrect answer and then resolved
against the real fix.
## Review-body follow-up at `da0d59cfb`

The re-review at `8daf7f091 + 82dc22b5d` listed four items in its
summary that had no inline thread of their own, so they had not been
picked up. All four are now fixed.

Both event-dispatch permission gates had been tightened from not-Bad to
`IsGood`, which silently dropped events whose permission verdict is
Uncertain; the data-change path in the same file still treated Uncertain
as deliverable, so the two had diverged. `EventSourceRegistry` only
cleared `ConsecutiveFailures` when a source was deactivated, so a source
that had backed off to the 30-second cap kept that delay for the rest of
the process even after starting successfully.
`UserNameIdentityTokenHandler` built a temporary issuer chain whose
`Add` calls take independent certificate references, and never released
them.

The fourth was the receiver-side sequence rollover, which the reviewer
had correctly re-flagged as still open despite its thread being
resolved. `m_sequenceRollover` was set permanently, so the second legal
wrap on a long-lived channel was rejected and faulted the channel along
with the transport-reconnect OPN. OPC 10000-6 does not cap a
SecureChannel at one wrap. The flag is now cleared once an accepted
number has traversed the normal range, which keeps rejecting a replayed
low number that never left the rollover window.

Validated on net10.0 and net48: 636 / 593 Core cases and 135 / 134
Server cases pass, including the new
`UaSCBinaryChannelSequenceRolloverTests` and the Uncertain-permission
delivery cases. The build reports zero compiler and analyzer diagnostics
and the changed files pass included-file info-format checks on both
targets.

The previous head `085fd9636` was fully green: 279 checks passed and
Azure build 18414 succeeded with 137 of 137 jobs, after the platform
automatically retried a job whose NuGet tool download had hit a
transient TLS error.
## Reported issues #4508 and #4509 at `6ad1ecf16`

**#4508 (V2 subscription recreate deadlocks against a faulted transport)
was not yet fixed and is now closed by `bac260a06`.** Both drain sites
the report identifies were still unbounded. A publish worker that
started its request before the quiesce parks inside the service call on
the channel ready gate while holding an active publish request; the
recreate that would make the channel ready is the very operation
awaiting the drain, so the wait never ends.

The drain now cancels in-flight attempts through a per-attempt token
linked to the worker token. An aborted worker rolls its acknowledgements
back, releases the request and returns to the paused park instead of
terminating, so it resumes when the caller leaves the quiesce. Publish
ingress stays quiesced for the caller's operation, so
`DropPendingForSubscription` keeps the guarantee the report asks to
preserve and no blind timeout is added. The new regression parks a
worker on a cancellable gate that never completes on its own: it
reproduces the hang for the full 30-second budget before the change and
passes after it.

**#4509 (identity provider fails the initial connect) was already fixed
for its primary symptom.** `HandleConnectAsync` materializes the
provider's identity through `CreateIdentitySelectionContext` before the
first `CreateAsync`, so Anonymous is no longer substituted against a
UserName-only endpoint. `6ad1ecf16` adds the two remaining details from
the report: the enabled-policy set now includes the negotiated channel
policy, so a client cannot reject the policy it already accepted as
`NotEnabledByClient`; and when discovery has not populated the
endpoint's token policies the connect keeps the configured identity so
the attempt fails at the transport layer for the reconnect policy to
retry, instead of failing at the identity layer.

Validated on net10.0 and net48: 477 / 473 client session and
subscription cases pass, the build is free of compiler and analyzer
diagnostics, and the changed files pass included-file info-format checks
on both targets. The full `Opc.Ua.Sessions.Tests` suite also passes
locally on net10.0 with 782 passed and 379 pre-existing capability
skips.

GitHub checks are green on this head: Build and Test .NET 10.0, Docker
Sample Images CI, and NuGet Publish all succeeded. Azure build 18417
completed 134 of its 135 jobs successfully; its net10.0 Sessions job was
cancelled by the hosted-agent provider ("Received request to
deprovision"), the same infrastructure flake that hit build 18409
earlier on a head predating these changes. That job is not claimed as
passing, and the local full-suite run above covers the same project. The
previous head `da0d59cfb` completed Azure build 18415 with every job
succeeded.
## Review follow-up at `a08f0c12b`

Eleven new review threads arrived, nearly all documentation. Before
acting on each "this is new in 2.0" remark I checked the API against
`master378` rather than assuming, because a genuine 1.5 API still needs
its migration entry.

`ManagedSession`'s server-redundancy refresh had two hard-coded
two-second bounds. The new `ServerRedundancyOptions` exposes
`RefreshTimeout` for the metadata read and `PeerDiscoveryTimeout` for
each peer lookup, defaults both to the previous two seconds, validates
that a bound is positive or `Timeout.InfiniteTimeSpan`, and flows
through `ManagedSessionOptions`, `ManagedSession.CreateAsync`, the
fluent builder, and `DefaultServerRedundancyHandler`.

`AsyncCustomNodeManager` and `KeyCredentialBridgeAuthenticator` are both
absent from `master378`, so their obsolete members had no compatibility
constraint and are removed rather than carried:
`AsyncCustomNodeManager.ReadInitialValue`, the audience-less
`CreateTokenData` that only threw, and the audience-less `CreateProof`
that produced a proof no server accepts.
`CustomNodeManager2.ReadInitialValue` and the `MonitoredNode2` migration
section are genuine 1.5 APIs and are untouched.

The documentation now states master's behaviour instead of the delta
from 1.5.378, with each moved item already covered under
`docs/migrate/2.0.x/`. `IHistorianAnnotationProvider` is described by
its annotation-time key rather than as "legacy" — it is new in 2.0, so
the label implied a compatibility constraint that does not exist. The
KeyCredential bridge payload's `"version"` field is explained as a
vendor-extension format version with no OPC UA counterpart, and its
version-1 upgrade narrative is gone. `CertificateManager.md`'s migration
walkthrough is replaced by the resolver API it targets.
`NodeManagers.md`, `Sessions.md`, `AsyncServerSupport.md`,
`Certificates.md`, and `Profiles.md` no longer announce features
relative to 1.5. `Benchmarks.md`, `WhatsNewIn2.0.md`,
`DeveloperGuide.md`, and `docs/migrate/` keep their 1.5.378 references,
which are their subject.

CI then exposed a defect this batch introduced: five fixtures resolve
`ManagedSession`'s private constructor by its exact positional parameter
types, so the added parameter compiled cleanly but made `GetConstructor`
return `null` at run time. `7df1d5c40` updates every site;
`Redundancy.Client` passes 126 of 126 and the affected client fixtures
112 of 112.

The BouncyCastle question is answered and tracked in #4510:
`Opc.Ua.Core` already project-references `Opc.Ua.Security.Certificates`,
which already carries the conditional BouncyCastle reference, so the
raw-ECDH polyfill belongs there rather than as a new Core dependency.
The `IUserDatabase` metadata question is addressed to another maintainer
and is deliberately left open.

## Reported issue #4509 follow-up at `5d4d13d63`

The reporter verified `6ad1ecf16` and found one case still failing,
correctly. The empty-token-policies branch kept the configured identity
so a server that is down surfaces a transport failure rather than an
identity error. A provider-only configuration has no configured
identity, so it kept `null`: `OpenCoreAsync` turned that into Anonymous
and `OpenValidateIdentity` rejected it with `BadIdentityTokenInvalid`,
silently ignoring the configured provider.

The branch now requires a configured identity to defer to. Without one
the provider is consulted, so its own `BadIdentityTokenRejected` names
the offered and rejected policy set instead. Two regression tests cover
both configurations; the first fails against the previous behaviour by
reaching the session factory with a `null` identity, which is the exact
step that produced the reported error. That branch had shipped without a
test, which is why the case was missed.

## Review and CI status at `5d4d13d63`

**All actionable review threads are resolved: 132 of 133.** The single
open thread is a question the reviewer addressed to another maintainer
about moving user metadata into `IUserDatabase`; it is left open for
them rather than resolved silently. Every resolved thread carries a
reply naming its fix commit.

**Latest-head CI is green on `5d4d13d63`: 279 checks passed, zero
failed, zero pending**, with one conditional signed-package publishing
job skipped. Local validation for this batch: the full
`Opc.Ua.Client.Tests` suite passes 2,430 of 2,430 on net10.0,
`Opc.Ua.Redundancy.Client.Tests` 126 of 126, and `Opc.Ua.Server.Tests`
590 of 590 for the affected selections. Both net10.0 and net48 build
clean for `Opc.Ua.Client`, `Opc.Ua.Server`, and the changed test
projects, and all changed files pass included-file info-severity
formatting on both targets.

The PR remains open; no merge was performed. As stated at the top, this
does not claim that every item in the 244-finding audit backlog is
complete.
## Latest CI follow-up at `b6f2dfa43`

Azure build 18442 exposed a net48 compile regression in the Kafka
adapter: `RuntimeHelpers.GetUninitializedObject` is unavailable on .NET
Framework. Commit `2cf1e0eed` now uses normal `ProducerMessage`
construction on `NETFRAMEWORK` while retaining reflection-based
construction for modern targets that can load a different Dekaf runtime
asset. The exact net48 CI selection passes 92 of 92 tests, and the
netstandard2.1 adapter guard selection passes 11 of 11.

After merging the latest `master`, GitHub Actions run 35643592139 is
green. The initial Ubuntu Core.Schema job built successfully and passed
160 of 160 tests, then hit an external 403 while finalizing its
test-result artifact; its failed-job rerun completed successfully. Azure
build 18451 was canceled when its remote provider deprovisioned the
net10.0 Sessions runner (`Received request to deprovision: The request
was cancelled by the remote provider`). Azure attached no test task log
or source error, and the canceled parent left that child check stale as
in-progress. No source workaround, test skip, or check relaxation was
made for either infrastructure failure.

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: 68f26810-22b8-476f-abcd-0a8c82d6e208
2026-09-22 09:10:58 +02:00
Marc Schier fa8d45f2cf Fix server/core validation, lifecycle and protocol regressions (#4477)
# Description

**Server/core audit fixes with regression tests. Latest review-fix
validation, merge validation and earlier acceptance results are
distinguished below.**

This addresses a 95-finding server/core report. Every finding was
reviewed with
the OPC UA specification knowledge base or, where the standard does not
prescribe a C# implementation, the corresponding ownership/configuration
contract. Incorrect or withdrawn subclaims remain qualified rather than
being
presented as additional fixes.

The original checkpoint covers session identity/certificate validation
and
revocation; certificate/key ownership and transactional updates; TCP
reconnect,
receive/admission and buffer lifetime; HTTP quotas; subscription
admission,
durability and pooled payloads; file-operation lifecycle; historian
aggregates;
fluent/state-machine behavior; and related utilities. It includes
targeted
regressions and directly related documentation.

The approved acceptance cleanup is separate in the commit history:

| Cleanup | Verified result |
| --- | --- |
| Invalid identity-policy and KeyCredential fixture inputs | Fixtures
explicitly advertise Username and use its generated policy ID.
Credential persistence uses valid clear mode inside the existing
encrypted admin context. Original permission, lockout and negative
encryption assertions remain. |
| Native GDS lifetime and concurrent connection failures | Retain
ApplicationInstance until client teardown. A deterministic native
reproducer proved the test-only channel cap of 10 was exhausted;
removing that override restores the existing bounded default of 1000. No
global serialization or production quota change. |
| Stress certificate ownership and close accounting | Balance two helper
references and the fake transport's server-certificate ownership.
Replace the invalid event-count bound with exactly-once physical
disposal, opens = closes, zero active entries and one logical entry
lifetime. |
| Participant deadlines | Use the injected TimeProvider with the
existing cross-framework WaitAsync overload. Tests pin one tick before,
exact expiry, terminal notification, recovery and timely completion. |
| Reproducibility and platform assertions | Preserve canonical WoT
bytes/hashes, explicit display-culture contracts and exact
numeric-vector assertions. Accept Apple's CryptographicException subtype
without weakening disposal balance. |
| Missing user-signature proof | Reject null/empty proofs before OS
crypto. Return BadUserSignatureInvalid per Part 4, 5.7.3.3. None-policy
and valid-signature controls remain. A CI-only test nullable-context
error was corrected without changing production behavior. |
| Durable sample restore and shared test storage | Dequeue waits for
actual batch residency instead of treating failed restore completion as
success, and restored files close before deletion. Five deterministic
regressions failed before the fix. The two fixtures that clear the
shared batch directory are isolated; all original 3,000-item assertions
remain unchanged. |

## Latest review follow-up

Commit `828856850219518970e8e2f580b8f94b3c1fc748` fixes the deferred
robotics
disposal reported in the latest review.
`RobotIntentNodeManager.DisposeAsync`
now joins a shared controller-host drain and then explicitly awaits base
node-manager disposal. A controller's bounded shutdown wait may defer
its
cleanup, but no longer lets the node-manager override finish early.
Concurrent
callers, including an asynchronous call after synchronous `Dispose`,
cannot
bypass the drain after the host list has been detached.

Synchronous disposal remains nonblocking for deferred work. Deferred
initialization failures are logged and retained, and base cleanup
failures
propagate to asynchronous callers. The existing controller-level bounded
disposal contract is unchanged; the node-manager contract is documented
in
`docs/Robotics.md`.

| Regression requirement | Evidence |
| --- | --- |
| Wait for deferred hosts; preserve synchronous compatibility and
concurrent joins | `NodeManagerAsyncDisposalWaitsForDeferredHostsAsync`:
four cases covering both entry-point orders and zero/positive host
shutdown waits. All four failed before the fix. |
| Wait through base cleanup and observe failures |
`NodeManagerDisposalWaitsForBaseCleanupAndReportsItsFailureAsync`: four
cases hold the actual base-resource semaphore, verify pending callers
after the host finishes, then check success or the same propagated
exception and exactly-once cleanup. |

The focused `IntentHostingCoverageTests` and
`IntentControllerHostTests.Dispose`
selection passed **30/30 on net10.0 and 30/30 on net48**, with no
failures or
skips. The final net10 solution build passed with zero errors and only
the four
previously documented CA2249 warnings in unchanged fuzz-test code. No
new
warnings, analyzer suppressions, dependencies, or weakened assertions
were added.
The review thread received a commit-specific reply and was explicitly
resolved.

This verification is scoped to the robotics feedback; the earlier full
Subscriptions-run limitation remains recorded in the merge section
below.


## Documentation review follow-up (2026-09-14)

Commit `f9a9686fcc5d3cfd19cbbc8c2d826e20f5c7e72f` addresses the six
follow-up
threads on documentation and implementation rationale. Each has an
in-thread
reply citing the commit and an explicit resolution.

Multiline XML documentation now covers the declarations introduced or
modified
throughout the entire PR, including internal contracts, samples, tests,
and
public members of related private helpers. A syntax-aware inventory
checked
**2,031 declarations across all 256 PR C# paths with zero documentation
gaps**.
A supplementary check also covers **75 previously unchanged public
members**
of private helpers involved in the changed code. Token comparison across
the
conditional-compilation branches proves this follow-up changes **no
executable
C# or test assertions**. Project-file changes are rationale comments
only.

The implementation questions are documented at their source:

| Question | Resolution |
| --- | --- |
| Certificate assembly friendship | Server Push configuration reuses the
internal explicit-subject CSR helper with the existing key; no public
crypto API was added. |
| Core.Types assembly friendship | Server builders use internal
transition callbacks/revision guards; Server.Tests checks the revision
deterministically without creating a public compatibility contract. |
| Always-single-reader notifications | One dequeuer preserves event
order; optional concurrency fans out within one event and joins before
the next event. |
| Asynchronous disposal completion | `DisposeAsync` already joins the
completion published after admitted operations and all cleanup attempts.
The compatibility `Dispose` remains nonblocking to avoid deadlocking an
admitted callback against its own drain. |

The requested detailed review disposition follows. It distinguishes
actual
fixes from confirmed policies and incorrect subclaims rather than
counting every
comment as a new runtime change.


### Detailed disposition of review 5191795284

The [SDK
review](https://github.com/OPCFoundation/UA-.NETStandard/pull/4477#pullrequestreview-5191795284)
was submitted against `1c4a9df6c`, before the subsequent merge and
feedback fixes.
Its **15 inline threads** have each received an action-specific reply
and an
explicit resolution. A fresh GraphQL query verified those replies and
resolution
states; the fixes in `b8a59990f` remain ancestors of the current branch.

| Review concern | Action and disposition | Concrete regression evidence
|
| --- | --- | --- |
| Injected certificate-store providers bypassed | **Fixed.**
Registration, configuration snapshots, and validation use the injected
providers. Explicit custom types remain authoritative; the built-in
Directory catch-all is deferred so native X509 paths and later custom
providers are not captured. Failed store opens dispose the created
store. | `InjectedProviderResolvesRegisteredAndConfiguredTrustStores`
covers default-provider ordering and both registration paths; provider
validation/open-failure cases and the unchanged
`TrustedCertificateInjectedViaIndependentX509StoreIsObservedAsync` cover
real use and independent-store visibility. |
| Unguarded timer-thread leadership callbacks | **Fixed.** Each
subscriber's exception is logged independently and cannot suppress
subsequent subscribers or fail lease operations. `IsLeader` reads the
deadline without invoking application callbacks. |
`ThrowingLeadershipSubscriberDoesNotFailAcquireOrDisposeAsync`,
`ExpiryNotifiesOtherSubscribersWhenOneThrowsAsync`, and
`IsLeaderDoesNotDispatchExpiryNotificationsAsync` were all demonstrated
failing before the fix. |
| Legacy pending-key provider accepts an unfinishable regenerated CSR |
**Fixed by explicit capability validation.** A provider implementing
only `IPendingCertificateKeyStore` receives `BadNotSupported` before key
generation or persistence when regeneration is requested. Existing-key
CSR/update remains supported. Regeneration requires matching-only
consumption; no unsafe destructive probing was introduced. |
`LegacyPendingProviderRejectsRegenerationBeforeCreatingOrSavingAKeyAsync`
checks no key or store mutation;
`LegacyPendingProviderCompletesExistingKeySigningAndUpdateAsync` proves
the supported flow completes. |
| Shutdown waits behind user deactivation | **Fixed.** Accepted
deactivations drain before the master's lifecycle gate is taken.
Configuration retains its binding until the shared drain completes,
including concurrent shutdown callers and direct master disposal. | Four
cases of `ShutdownDrainsDeactivationOutsideTheSessionClosingGateAsync`
exercise real configuration/binding/ServerInternalData/master reentry,
retained address space, exact session/subscription closure, and no
production cancellation shortcut. |
| Subclass cleanup runs under the operation-lifetime lock | **Fixed.**
Cleanup starts outside that lock. A pre-published completion joins all
disposers, and only the active asynchronous teardown context may use
guarded helpers. Captured contexts lose that privilege when the callback
exits. |
`SynchronousOwnedCleanupLetsSamplingWorkerReachClosedAdmissionAsync`,
`DisposeCoreCanUseGuardedMembersWithoutReopeningCallerAdmissionAsync`,
captured-context rejection, and exact cleanup-failure/ownership
assertions cover both synchronous and suspended cleanup. |
| Discovery requestId-zero chunk read after pool return | **Fixed by the
earlier merge.** Discovery validation precedes `SaveIntermediateChunk`;
no read occurs after that path can return the buffer. The ordering is
retained. | `DiscoveryChannelReadsTheFirstChunkBeforeItIsReturnedAsync`
uses a poisoning pool and the requestId-zero path. |
| T1.8 OPN cleanup misses post-decryption throws | **Fixed by the
earlier merge and pinned with new regressions.** Both sequence rejection
and certificate mismatch release the decrypted body and input ownership.
| `OpenSecureChannelRejectionAfterDecryptionReturnsEveryRentalAsync`
checks the exact audit status and pool conservation. Omitting either
corresponding release in an isolated snapshot made its case fail; no
mutation remains. |
| T1.2 mount-root protection depends on the provider | **Fixed at the
host boundary.** Separator-only aliases resolve to the protected root.
Traversal, empty/whitespace segments, backslashes, and drive/stream
qualifiers are rejected before arbitrary providers are invoked. Valid
nested paths and root destinations remain supported. | A deliberately
permissive provider is used by
`NonCanonicalObjectPathsCannotDeleteMoveOrCopyAsync` and invalid-target
cases; exact zero-call checks are paired with legitimate
nested-path/root-destination controls. |
| Inline trusted/issuer entries now face CRL checks | **Intentional
strict behavior, documented and tested.** A configured backing store
with strict unknown-status rejection requires current revocation
information. Explicit-only lists without a store retain their no-store
behavior. Actual revocation cannot be suppressed; a matching store
entry's policy takes precedence. |
`InlineIssuerWithStoreHonorsStrictUnknownRevocationPolicyAsync`,
`InlineIssuerRevocationIsNeverSuppressedAsync`, store-precedence cases,
and explicit-only controls preserve the missing-information versus
actual-revocation distinction in Part 4 6.1.3. |
| RSA minimum applied to unspecified ECC identifiers | **Fixed at the
application-certificate check.** The RSA minimum is compared only with
an actual RSA public key. An unspecified ECC identity is not replaced
simply because its key size is below an RSA threshold. |
`SilentCertificateCheckPreservesUnspecifiedEccIdentityAsync` checks DER,
thumbprint, store contents, and private-key retention; explicit RSA and
HTTPS minimum controls remain. |
| Failed directory refresh wedges corrective mutations | **Fixed.**
Recoverable automatic pre-refresh failures are logged and leave
reconciliation pending, but do not block corrective provider mutations.
Explicit refresh errors, capacity admission, caller cancellation, and
actual provider denials remain enforced. |
`CorrectiveDeleteRecoversAfterPersistentOverLimitRefreshFailureAsync`
converges an externally over-limit directory back to its exact allowed
contents. Capacity, cancellation/token, and six refresh-error controls
check negative paths. |
| Timed-transition rejection logs at 10 Hz | **Fixed.** Repeated
`(state, revision, status)` warnings are deduplicated without changing
the retry cadence. A different status or state entry permits another
warning. | `RepeatedTimedRejectionLogsOnceAndRecoversAsync` checks one
warning over eleven rejections and success on the next attempt.
Status-change and same/different-state reentry controls pin reset
behavior. |
| Bad unsubscribe strands retired-generation bookkeeping | **Fixed.**
Retired all-event bookkeeping completes even when unsubscribe reports
Bad; the first Bad is still returned to the caller. | Good and
BadCommunicationError cases of
`RetiredAllEventsDeletionCompletesBookkeepingAndReleasesGenerationAsync`
check event/snapshot removal, generation release, and exactly one
unsubscribe without finalization replay. |
| CSR subject parsing and fallback | **Fixed for existing and
regenerated keys.** Omitted subjects fall back to the actual stored
certificate. Regeneration resolves the public certificate's subject
before creating a key. Malformed or unresolvable subjects return
`BadInvalidArgument` before pending-key mutation. | Store-only fallback,
real-generator null/empty cases, and missing-subject/malformed-DN
controls verify the signed CSR, matching fresh pending key, unchanged
active identity, and no destructive side effects. |
| Committed RemoveUser change reported as failed | **Fixed for
RemoveUser and ModifyUser.** Accepted cleanup is still awaited and close
failures remain logged, but cannot replace the committed mutation
result. Precommit failures retain their original result and side
effects. |
`CommittedUserChangeKeepsResultAndPublishedUsersWhenCloseFailsAsync`
checks published Users, Good result, logging, and continued closes.
`FailedUserChangeKeepsPublishedUsersAndDoesNotCloseSessionsAsync` checks
BadNotFound with no publication or close. |
| Alleged pooled decoded-request aliasing | **No runtime redesign
needed; reviewer rebuttal confirmed.** The decoder copies the relevant
input data. Misleading ownership comments were corrected rather than
introducing a new dispatch model. |
`DecodedRequestRetainsValuesAfterInputBuffersAreReturnedAsync` checks
the exact decoded NodeId and ByteString after returned arrays are
poisoned. |

The current documentation-only follow-up rechecked **104 Core, 473
Server, and
4 Configuration cases** covering these concerns: **581 passed, zero
failed or
skipped**. The final net10 solution build also passed with **zero
warnings and
errors**. The complete earlier Core/Server/Configuration and net48
results remain
listed separately rather than being presented as rerun current-head
acceptance.

## Earlier review follow-up

Commit `b8a59990fe2e8e967a12ffd5d9158beed7831143` addresses all 19
review
threads. Each thread has an in-thread reply naming this commit and was
explicitly
resolved after verification; the final paginated query found 19 resolved
and
zero unresolved threads.

The follow-up fixes injected certificate-store selection (including
default
provider ordering and native X509 paths), actual-RSA minimum
enforcement, and
CSR capability/subject validation before key mutation. Node-manager
teardown
uses simpler scoped ownership and drains accepted user revocation
outside the
master gate; committed user results and retired-event cleanup remain
correct
when cleanup reports failure. File mutations can recover after failed
refresh
without bypassing capacity or cancellation, provider paths protect mount
roots,
and repeated timed rejections no longer flood logs. Leadership
subscriber
failures are isolated without callbacks from `IsLeader`.

Regressions also pin the already-merged OPN/discovery buffer fixes and
prove
decoded request values do not borrow returned input buffers. The strict
inline
issuer revocation policy is documented and tested, not weakened.
Existing tests
were changed only for the reviewed behavior: the incorrect
committed-user result
was corrected, and inline-issuer/root-alias controls were expanded.

### Review-fix validation

| Suite | Scope | Framework | Passed | Existing TRX NotExecuted |
| --- | --- | --- | ---: | ---: |
| Core | Complete project | net10.0 | 4,970 | 88 |
| Server | Complete project | net10.0 | 6,414 | 69 |
| Configuration | Complete project | net10.0 | 231 | 0 |
| Core | Certificate, lease and buffer compatibility slice | net48 | 153
| 0 |
| Server | Reviewed lifecycle, user, file, timer and CSR compatibility
slice | net48 | 692 | 0 |
| Configuration | Complete project | net48 | 231 | 0 |
| CSR provider regressions | Final portable-mock follow-up | net10.0 |
11 | 0 |

All runs exited successfully with normal concurrency and leak detection.
The Server console reports 5 skips; its TRX additionally records
existing
assumption/explicit cases, hence the 69-record count above. The
Framework build
caught two modern-only `ValueTask.CompletedTask` usages in new mock
setup; only
those expressions changed to the equivalent portable
`default(ValueTask)`.
The complete modern suites precede that test-only correction; all
production
files remained byte-identical, and the corrected fixture passed on both
targets.

The final net10 solution build succeeded with 0 errors and the same 4
CA2249
warnings in unchanged fuzz-test code. Diff checks and changed-line
whitespace
checks are clean; whole-file formatting still identifies 10 unchanged
baseline
lines, which were not reformatted outside the feedback scope. The
committed
35-file tree was hash-verified against the validation inputs.

This is the review-feedback verification scope, not a rerun or sign-off
of the
historical complete platform/native/soak acceptance campaign below.


## Latest upstream merge

Merge `9d9bf679f317164c5b2b90924cd3cdc27a86d451` integrates `master`
through `162fc5ebb` (#4486),
including the AddNodes child-name index, shared certificate-error
reporting,
CTT sample-data corrections, and the accompanying regressions and
documentation.

The CreateSession conflict preserves this branch's certificate
ownership,
required certificate, application-URI, and channel-certificate checks.
The
validation result now retains nested errors through `ThrowIfInvalid`,
allowing
the upstream shared reporting helper to mask trust, policy, and
revocation
failures consistently without losing audit detail.

The new indexed AddNodes regression initially attempted to reuse a
deterministic
NodeId after renaming its existing node. Renaming frees the BrowseName,
not that
NodeId. `IndexedBrowseNameReusePreservesExistingNodeIdentityAsync` now
proves
both contracts: the derived-ID collision leaves the original node
intact, then
a fresh explicitly requested ID can reuse the old name while the new
name
remains protected against duplicates. No production identity rule was
relaxed.
The incoming seeded random-index test uses the existing `UnsecureRandom`
wrapper
with the same seed and sequence; no new analyzer suppression was added.

| Local merge validation | Framework | Passed | Existing exclusions |
| --- | --- | ---: | ---: |
| Core, complete project | net10.0 | 5,081 | 88 |
| NodeState / BaseInstanceState | net10.0 | 579 | 0 |
| Server node management, certificate and session-security selection |
net10.0 | 112 | 0 |
| InformationModel node-management services | net10.0 | 29 | 1 |
| NodeState / BaseInstanceState | net48 | 578 | 0 |
| Core certificate validation, error reporting and TCP buffers | net48 |
111 | 0 |
| Server node management, certificate and session-security selection |
net48 | 112 | 0 |

All selected runs exited successfully at normal concurrency: **6,602
passing
test executions**. Modified test assemblies were explicitly rebuilt, and
the
combined name/identity regression was verified by name in both net10 and
net48
results. No skips or weakened assertions were introduced.

The final `dotnet build UA.slnx -c Release --no-restore -m:1` with
`CustomTestTarget=net10.0` succeeded with **zero warnings and zero
errors**.
The resolved source and adjusted tests pass whitespace verification, and
their
source hashes match the validation inputs.

This is merge-specific verification. Earlier review results and the
previously
reported incomplete full Subscriptions runs below remain scoped to their
own
commits; they were not reopened or relabeled as passing by this
operation.

## Previous upstream merge (2026-09-15 morning)

Merge `c4694e20ab089c555af233642042133ff3a03ac8` integrates `master`
through `484d6c887`, retaining
#4481's shared Like parser/GDS query fixes, #4488's RequestHandle
recovery in
ServiceFaults, and #4487's expired-session and durable-transfer
corrections.

Three conflict resolutions preserve both sides:

- Alias searches now use the shared `LikePattern` implementation,
including
upstream malformed-list validation. A timeout overload retains this
branch's
100 ms per-alias deadline and `BadTimeout` reporting without keeping a
second
wildcard translator. The shared matcher's original unlimited overload
remains
unchanged for existing GDS/ContentFilter callers. New regressions cover
bounded prefix/list scans, reuse after timeout, and the alias service
result.
- Expired activation closes outside the session-manager gate using
upstream's
once-only timeout claim, audit, and diagnostic accounting. This branch's
  original-channel and security-policy checks remain in place.
- TCP buffer tests retain this branch's ownership, poisoning-pool and
post-decryption checks alongside the upstream RequestHandle/fault
overload
  tests; neither set was discarded.

The upstream HTTPS binary behavior is intentionally retained: a decoder
`ServiceResultException` produces HTTP 200 with an OPC UA ServiceFault
carrying
the decoder status, response timestamp, and recoverable RequestHandle,
rather
than the previous HTTP 500 text response. Other exceptions retain their
existing HTTP error handling.

| Local validation | Framework | Passed | TRX NotExecuted |
| --- | --- | ---: | ---: |
| Core, complete project | net10.0 | 5,054 | 88 |
| Sessions, complete project | net10.0 | 780 | 610 |
| Server aliases, expiry/security and subscriptions | net10.0 | 288 | 0
|
| GDS database, paging and live directory calls | net10.0 | 263 | 0 |
| Shared Like patterns and bounded evaluation | net10.0 | 109 | 0 |
| Subscriptions transfer/durability/service selection | net10.0 | 23 | 1
|
| HTTPS WebApi, complete project | net10.0 | 346 | 0 |
| InformationModel aliases | net10.0 | 54 | 5 |
| Shared Like patterns and bounded evaluation | net48 | 109 | 0 |
| Core fault handles, TCP/HTTPS and filters | net48 | 268 | 0 |
| Server aliases, expiry/security and subscriptions | net48 | 288 | 0 |

These selected runs exited successfully with normal test concurrency:
**7,582 passing test executions**. Sessions' console reports 379 skips;
the
TRX also contains conditional/assumption exclusions, so the table uses
the
actual 610 NotExecuted records. No skips or weakened assertions were
added.
The new `EvaluationTimeoutBoundsWorkAndPreservesPatternReuse` and
`SharedPatternTimeoutRemainsAnAliasServiceError` tests passed on both
targets.

**Validation limitation:** two unfiltered Subscriptions runs did not
produce
a final result and were stopped, including a retry with a hang guard.
They
are not counted as passing. The isolated failover fixture passed 2/2,
and the
transfer/durability/service selection above passed. The stall's cause
was not
established; no unrelated code or test was changed to conceal it.

The final `dotnet build UA.slnx -c Release --no-restore -m:1` with
`CustomTestTarget=net10.0` succeeded with **0 warnings and 0 errors**.
Whitespace verification passed for all hand-reconciled files, and staged
source hashes match the validation inputs.

These are merge-specific checks, not a new full platform/native/soak
acceptance
sign-off. Earlier review and acceptance evidence below remains dated to
its
own commit.

## Previous upstream merge (2026-09-14)

Merge `c3e09553e4d1509502d4ba751960d58491bea2cf` integrates `master`
through `6313e38a0` (#4478),
including the CTT-driven Part 13 aggregate corrections and FindAlias
argument
validation. The upstream tests and CTT documentation are retained.

The single conflict in `AliasNameWildcardMatcher` is reconciled through
the
branch's shared regex compiler: upstream malformed-pattern rejection and
`IsValidPattern` coexist with OPC UA character escaping,
whole-string/newline
matching, the 100 ms timeout, and service-level error reporting. The
upstream
ReferenceTypeFilter checks and chronological aggregate behavior are
preserved.

Local merge verification:

| Suite / selection | Framework | Passed | Existing skips |
| --- | --- | ---: | ---: |
| Server aliases, aggregates and historian | net10.0 | 1,011 | 0 |
| Server aliases, aggregates and historian | net48 | 1,011 | 0 |
| InformationModel aliases | net10.0 | 54 | 5 |
| Features aliases | net10.0 | 11 | 0 |
| Client aliases | net10.0 | 28 | 0 |
| History aggregate/historical-access consumers | net10.0 | 265 | 0 |

All selected tests passed at normal concurrency. The final net10
solution
build passed with 0 errors and 0 warnings.
The resolved file's whitespace check and the staged diff check passed.
These
are merge-specific checks, not a new full platform/native/soak
acceptance claim.

## Previous upstream merges

Integrates `master` through `8e874d073`, including the Client, Types,
Core and
source-generator audit fixes in #4471, #4473, #4474 and #4475, plus the
event queue-size revision from #4480. The merge commits are `150ea0439`
(26 conflict resolutions) and `a0e17c07c` (the base update that arrived
during
validation).

The overlapping fixes are reconciled rather than replacing either
branch:

- **Rejected-certificate retention follows this branch, as explicitly
requested:**
zero means unlimited history; negative values disable new storage while
preserving existing backend trimming behavior (Directory clears prior
history;
shared key/value leaves it intact). The processor and manager policy are
not
  redefined, and documentation/tests describe the distinction.
- Preserve owned certificate snapshots and borrowed validation-core
lifetimes
  alongside upstream cache invalidation, store-first CRL checks and
  `BadCertificateRevocationUnknown` for unsupported revocation lookup.
- Combine exactly-once chunk ownership, receive-loop cancellation,
stale-epoch
rejection and detach-before-adoption with upstream
signature-before-padding
  verification and secret cleanup.
- Preserve pooled `HttpClient` per-request configuration together with
bounded
response reads and deadlines that remain active through body
consumption.
Regression cases exercise already-used clients and both timeout
precedence cases.
- Retain the binary-compatible channel-key constructor and normalize
omitted
profiles; preserve exact profile filtering and upstream binary-first
HTTPS/WSS
  endpoint ordering.
- Preserve monotonic lease expiry and stale-confirmation fencing while
adding
ordered, non-reentrant leadership notifications outside the state lock.

## Validation

Local validation of the conflict-resolution merge:

| Suite | Framework | Passed | Existing skips |
| --- | --- | ---: | ---: |
| Core | net10.0 | 4,940 | 88 |
| Client | net10.0 | 2,278 | 0 |
| Server | net10.0 | 6,088 | 5 |
| Types | net10.0 | 10,394 | 1 |
| SourceGeneration.Core | net10.0 | 3,940 | 8 |
| SourceGeneration | net10.0 | 185 | 0 |
| Core | net48 | 4,855 | 104 |

After the subsequent four-file #4480 update, the related Server slice
passed
811 tests with 5 existing skips, the real durable queue-size cases
passed 6/6,
and EventManager's 21 cases passed again after analyzer-only
expected-array
cleanup. The final `dotnet build UA.slnx -c Release` with
`CustomTestTarget=net10.0`
succeeded: 0 errors and 4 pre-existing CA2249 warnings in unchanged
fuzz-test
code. Whitespace verification passed for the resolved files and the
follow-up.

Merge-specific proof includes
`RequestTimeoutRemainsActiveWhileReadingTheOpenApiBodyAsync` on
already-used
shared clients with either the request or HttpClient timeout shorter,
the
existing ownership/expiry regressions from both branches, and both
branches'
retention tests adjusted only to the explicitly chosen zero/negative
contract.

Earlier acceptance at `1c4a9df6c` passed hosted Linux/macOS CI, CodeQL,
image
builds and the canonical coverage gate (87.15% line, 77.27% branch,
92.14% patch).
Both Framework project matrices, all three Windows native suites (183
cases),
and the unfiltered net10 stress project (230 cases, including full
60-minute
chaos and 30-minute memory soaks) also passed. Those are **pre-merge
results**,
not a claim that the full framework/platform/native/soak matrix has been
rerun
on this merge. The previous acceptance workflow remains separate from
this
review-feedback operation.

Security checks, meaningful assertions, leak detection, default native
concurrency, full soak durations and coverage thresholds remain intact.
The user-set ready-for-review state is unchanged. No architectural or
complete
merged-head acceptance sign-off is claimed.

## Related Issues

- Fixes #4476

## Checklist

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [x] I have addressed **all** PR feedback received.
2026-09-16 04:42:09 +00:00
romanett 162fc5ebb3 Fix AddNodes scaling and OpenSecureChannel revocation errors found by CTT Monitored Item, Node Management and security runs (#4486)
# Description

Findings from running the CTT conformance groups **Monitored Item
Services**, **Node Management Services**, **Security General** and
**Security User Token** against `ConsoleReferenceServer --ctt` (CTT
1.05.06, scripts 1.05.513). The security groups ran **without `-a`**,
against an isolated server PKI built from the CTT's `copyToServer`
folders, so the negative certificate tests are meaningful.

## Server fixes

### AddNodes below one parent was quadratic (Node Management Delete Node
`Err-002.js`)

The CTT adds 15,000 variables below `ns=2;s=CTT` in batches of 5,000 and
warned that AddNodes responses took 400–800 ms. For every added node the
server searched all children of the parent twice: once in the BrowseName
duplicate check in `AsyncCustomNodeManager.AddNodeCoreAsync`, which also
copied the children list, and once in the NodeVersion lookup of
`FilterChangesByNodeVersion`.

- `NodeState.FindChild` now searches children lists with ≥ 64 entries
through a BrowseName index kept in a `ConditionalWeakTable`, so nodes
with few children get no extra field.
- It keeps first-match semantics and is maintained by
`AddChild`/`RemoveChild`.
- It is dropped on replacement and invalidated when a child is renamed
or moves to another parent.
- Lists whose children point at another parent (clones) are still
searched linearly.
- The duplicate check uses `FindChild` instead of copying the list.

| 5,000-node AddNodes batch (in-process, Debug) | 1st | 2nd | 3rd |
| --- | --- | --- | --- |
| before | 769 ms | 2,083 ms | 4,011 ms |
| after | 141 ms | 166 ms | 172 ms |

In the CTT, AddNodes of 5,000 items now answers in 51–72 ms and the
warning is gone.

### OpenSecureChannel leaked revocation errors (Security Certificate
Validation `002.js`)

Part 4 §6.1.3, Table 106:
- For the revocation check (`Bad_CertificateRevoked`,
`Bad_CertificateIssuerRevoked`), `Bad_SecurityChecksFailed` **shall** be
reported to the client.
- For a missing revocation list (`Bad_CertificateRevocationUnknown`,
`Bad_CertificateIssuerRevocationUnknown`), it **should** be.

`TcpServerChannel` masked only `Bad_CertificateRevoked`, and
`StandardServer.OnApplicationCertificateError` (CreateSession) had its
own list that missed `Bad_CertificatePolicyCheckFailed`. Both now use
one helper, `CertificateErrorReporting` in Opc.Ua.Core, which also
inspects the nested errors of the certificate validator (both paths now
throw the validation result with `ThrowIfInvalid`). Only validity
period, host name, URI and usage errors keep their own code, and audit
events still carry the specific result. The CTT warning is gone.

### Sample data

- **Monitor Value Change V2 `020.js`** skipped because
`Scalar_Static_Arrays_ByteString` had a 1-byte and a 3-byte element. The
script checks every element, and the simulation only padded elements
0–2. The seed value now has no element shorter than four bytes, and the
simulation pads every element.
- **Monitor Value Change V2 `042.js`** got 18 of 19 notifications. The
missing item is the Float matrix: its element [1,1] was
`-1.03179664E+33`, where adding 1 is below Float precision, so the value
really did not change. The server did not drop a notification. The
element is now `-1031.79664`.

## CTT results after the fixes

| Group | Result |
| --- | --- |
| Monitored Item Services (208) | Monitor Value Change V2 44/44.
Remaining: Monitor Basic `039.js` (C17, missing include), `038.js`
warning (C32), and 1–2 sporadic timestamp-tolerance warnings that move
between test cases from run to run. |
| Node Management Services (15) | Only Add Node `Err-008.js` (Mantis
11266). |
| Security General (314) | Certificate Validation: 23 pass, 24 not
implemented, 3 not-applicable skips. None CreateSession/ActivateSession:
all pass. The other 50 CUs are *Not Implemented* in scripts 1.05.513. |
| Security User Token (66) | Anonymous `002.js` (C35) and User Name
Password 2 `015.js` (C36) fail because of CTT defects. X509: 18/18
automated cases pass. |

## CTT defects documented (`plans/ctt-issues.md`)

- **C32** `038.js` compares a RevisedSamplingInterval of 0 with a
project setting instead of the node's MinimumSamplingInterval or the
server's MinSupportedSampleRate.
- **C33** `020.js` requires every ByteString element to be ≥ 4 bytes,
but its message says elements 0–2.
- **C34** `RequestedNewNodeId()` always sends `ns=1`, regardless of
`RequestedNodeId_Namespace`, so client NodeIds can't be enabled.
- **C35** Security User Anonymous picks the `opc.wss` endpoint, which
the CTT cannot open (`BadNotSupported`).
- **C36** `UaEndpointDescription.FindTokenType` rewrites the cached
endpoints' token policies, so `015.js` reports PolicyIds as reused. The
server's GetEndpoints output was verified compliant (PolicyIds unique
per configuration, Mantis 11258).
- Evidence added to **C9** (042.js) and **issue 17** (015.js).

`plans/ctt-testing.md` gains how to run the Monitored Item/Node
Management groups and a recommended setup for the security groups:
isolated PKI from `copyToServer`, no `-a`, PKI restore per part, and
waiting for `Server started`. Other findings recorded there:
- the Create/DeleteMonitoredItems timing warnings are jitter;
- `LoginNameAccessDenied` is not a real user;
- `samples\UAReferenceServer.ctt.xml` needs no change (enabling
`RequestedNodeId` breaks six Add Node cases because of C34).

**Note:** `plans/ctt-testing.md` and the refreshed `plans/ctt-issues.md`
are introduced by #4482. The plans files here are based on #4482's
versions, and new entries start at C32 because #4481 uses C19–C31.
Please merge after #4482 (or rebase the plans files onto it).

## Tests

- `NodeStateChildNameIndexTests` (Opc.Ua.Types.Tests): index semantics
(duplicates, remove, rename, replace, re-parent, clone, shrink/grow,
2,000 random operations against a linear search). Also a scan guard:
5,000 misses against 50,000 children take 97 ms with the index and 7,083
ms with it disabled.
-
`AsyncCustomNodeManagerNodeManagementTests.AddNodeAsync_DuplicateBrowseNameUnderParentWithManyChildren…`
- `TcpServerChannelCertificateErrorTests` (Opc.Ua.Core.Tests): masked vs
reported certificate errors.
- Opc.Ua.Server.Tests 5,553 passed, Opc.Ua.Core.Security.Tests 556
passed, Opc.Ua.Core.Tests (Security + Stack) 3,561 passed,
InformationModel NodeManagement 26 passed (net10.0).
- Opc.Ua.Types.Tests 10,404 passed and 1 failed:
`WotSpecFixtureManifestTests.EveryEmbeddedExampleMatchesItsRecordedHash`.
That test hashes WoT assets which are `eol=lf` in the index but CRLF in
this worktree's checkout; no WoT file is touched by this PR.

## Checklist

- [x] I have signed the CLA and read the CONTRIBUTING doc.
- [x] I have added tests that prove my fix is effective or that my
feature works.
- [x] I have added all necessary documentation.
- [ ] I ran all tests locally using UA.slnx against .NET Framework and
.NET 10 (net10.0 suites listed above only).

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

---------

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: romanett <7413710+romanett@users.noreply.github.com>
2026-09-15 10:08:30 +00:00
romanett 747f635518 Fix the Opc.Ua.Core defects from the server/core audit (#4475)
# Description

Fixes every `src/Opc.Ua.Core` item found by a twelve-reviewer audit of
`src/Opc.Ua.Server` + `src/Opc.Ua.Core` taken at 0e600c0f0, across all
three tiers of that report (security/data-loss/crash, confirmed
functional, and reviewer-traced). **The `src/Opc.Ua.Server` half of the
audit is deliberately out of scope here** and remains open.

## Security and resource safety

- **Explicitly configured trusted certificates were ignored.**
`CertificateTrustList.TrustedCertificates` (the `<TrustedCertificates>`
config element, `SecurityConfiguration.AddTrustedPeer`) never reached
the validator, so a peer trusted only that way was rejected with
`BadCertificateUntrusted`. The list now travels from configuration
through `TrustListEntry` into `TrustListState`, and is consulted both
when deciding trust and when completing a chain — OPC 10000-4 6.1.3:
"The list of trusted Certificates may contain a Certificate issued to
another Application or it may be a Certificate belonging to a CA". The
store is still consulted first, so a CA configured both ways keeps its
CRL check. Cached validation cores are evicted when a trust list is
re-registered, so a reconfiguration actually takes effect.
- **Unauthenticated receive-buffer leak.** `SaveIntermediateChunk` now
always takes ownership of the chunk: it either stores it or returns it
to the `BufferManager`. A server without a `None` endpoint gives every
TCP client a discovery-only channel, and each non-discovery request
leaked one `ReceiveBufferSize` buffer. Added `TakeSavedChunks` for the
"body already saved" case; passing the chunk again would have queued the
same buffer twice. A channel torn down while a multi-chunk message is
still arriving now releases what it had buffered, which nothing did
before.
- **Decrypted OpenSecureChannel buffers** are returned when verification
fails, including the sibling paths where the sequence-number or
certificate check rejects the message *after* the body was handed back.
- **RSA Diffie-Hellman peer values** are validated against `2 <= y <=
p-2` (RFC 7919 5.1), so the shared secret can no longer be forced to a
known constant by sending 0, 1 or p-1.
- **`RemovePadding` verified no padding at all** for channel messages:
the loop started at `data.Offset` and stopped at `paddingSize`, so on
any message with a header it ran zero times. The filler loop is
corrected — OPC 10000-6 6.7.2.5.1: "The value of each byte of the
padding is equal to PaddingSize" — and the signature is now checked
*before* the padding is inspected so the two failures cannot be told
apart.
- **Key material zeroing** on the ECC secret path: the plain text, the
derived key and IV, and the ECDH shared secret, on both sides. The
decrypt wipe covers the failure path too, which is the one that matters
— the body is decrypted in place before the signature is verified.
- **HTTPS responses** are read with `ResponseHeadersRead` and bounded by
`MaxMessageSize`, instead of the whole body being allocated before the
limit was applied.
- **`X509CertificateStore.IsRevokedAsync`** reports an unanswerable
revocation check as `BadCertificateRevocationUnknown` instead of
throwing. The throw surfaced as an unsuppressible
`BadCertificateInvalid` and failed every CA-issued certificate on Linux
and macOS. See reviewer note 2.
- **Certificate handle ownership**: `ClientChannelManager` AddRefs what
it hands to a transport that disposes it (and releases it again when the
channel never opens), `CertificateTrustList` releases the handle `Add`
took its own reference to, and `X509CertificateStore` disposes the
platform handles nothing else owns.

## Transport

- The receive loop is now **one atomically swapped epoch of (transport,
token)**, so a reconnect that binds a new socket to an existing channel
supersedes the old loop rather than racing it. Previously the supersede
path was unguarded and could start two readers on one socket, dispose an
in-use `CancellationTokenSource`, and leak one per reconnect.
- A **reconnect hand-over detaches the transport before closing
anything**, so the socket the adopted channel now answers on is not
closed underneath it. Previously the queued `OpenSecureChannelResponse`
failed with `BadConnectionClosed` and reconnect to a dropped channel
could never succeed.
- A blocked or unservable **accepted socket is closed** rather than left
open until process exit.
- An **invalid response sequence number reconnects the channel** instead
of throwing into a handler that did nothing, which left the pending
request hanging until timeout. OPC 10000-6 6.7.7 requires the receiver
to close the channel, and the same section requires the error to be
logged — which `HandleMessageProcessingError` now does instead of
discarding it silently.
- The **abort chunk** is encoded against the room the chunk has rather
than what it currently holds, so a short offending chunk can still carry
the error body (OPC 10000-6 6.7.3).

## Discovery and endpoints

- `GetEndpoints` no longer drops the HTTPS and WSS JSON/OpenAPI
endpoints, and no longer collapses them onto the binary one (the dedup
ignored `TransportProfileUri`). `profileUris` filtering matches them too
— OPC 10000-4 5.5.4.2 defines it as the "List of Transport Profile that
the returned Endpoints shall support", and a client asking for the JSON
profile previously got an empty list back. Results are ordered
deterministically with **binary first**, so a client that takes the
first endpoint that fits keeps getting the one it got before these twins
were published.

## Smaller confirmed defects

`FilterEvaluator.InList` returned after the first string operand;
`SelectedUserTokenPolicy` setter always ended at `-1`;
`Utils.UpdateExtension` could not delete; a lease holder never stepped
down while the shared store was unreachable *or hanging*;
`IsUriHttpRelatedScheme` never matched `http`;
`SessionLessServiceMessage` dropped a single `LocaleId`;
`GetRandomDouble` used `ToSingle` and typed variant arrays ignored the
requested `builtInType`; source-generated log calls never reached the
trace file.

## Related Issues

- No tracking issue was opened for this work; it derives from an audit
report rather than a filed issue. Happy to open one and link it if
maintainers prefer.

## Notes for reviewers

1. **`MaxRejectedCertificates` semantics.**
`ICertificateStore.AddRejectedAsync` documented "0 is unlimited", but
`DirectoryCertificateStore` wrote every certificate and then deleted all
of them at 0 (net effect: store nothing), and `CertificateManager`
clamped a negative value onto 0 and *depended* on that to implement
"clear the store". `SharedKeyValueCertificateStore` meanwhile treated 0
as genuinely unlimited, so the two store types did opposite things at
the same setting. This PR keeps the existing observable behaviour (0 or
less keeps no history and clears what is stored), removes the
write-then-delete-all churn, aligns the KV store, and corrects the
interface doc and `docs/DependencyInjection.md`. **The KV store is the
one place whose behaviour changes** relative to master.

2. **Revocation status where X509Store has no CRLs.** `IsRevokedAsync`
used to throw there, which surfaced as an unsuppressible
`BadCertificateInvalid` and failed every CA-issued certificate on Linux
and macOS - the outage the audit flagged. It now returns
`BadCertificateRevocationUnknown`, which is what the Windows branch of
the same method and a directory store without a CRL already return, and
the status `RejectUnknownRevocationStatus` decides on (OPC 10000-4
6.1.3, Find Revocation List). With the default policy the certificate is
accepted; an operator who opted into strict mode gets a rejection, as
before on master. An earlier revision returned `BadNotSupported`, which
the validator discards outright and which made revocation fail open even
in strict mode; review caught it.
3. **`ManagedChannelKey` gained a `TransportProfileUri`** property and
an optional trailing constructor parameter. Source-compatible, but it is
public API.

## Checklist

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [ ] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

### Regression test coverage

Each of these fails against `master`'s source and passes with the fix.

| Fix | Test |
|---|---|
| Padding filler bytes were never verified |
`CryptoUtilsSymmetricPaddingTests` — forged filler rejected, plus a
round trip over every padding length |
| Padding removed before the signature was checked |
`CryptoUtilsSymmetricPaddingTests.SymmetricDecryptReportsSignatureFailureAheadOfPadding`
|
| RSA-DH peer value not range checked | `RsaDiffieHellmanPeerValueTests`
— 0, 1, p-1, p, above p, both range boundaries, group mismatch |
| A degenerate DH nonce threw instead of being rejected |
`UaSCBinaryChannelNonceTests` |
| `<TrustedCertificates>` never reached the validator |
`CertificateValidationCoreTests` (peer, issuer, and the negative
control),
`CertificateManagerTests.ExplicitlyTrustedPeerFromConfigurationIsAcceptedAsync`
|
| Cached validation cores survived a trust-list change |
`CertificateManagerTests` — registration after a failed validation, and
`UpdateAsync` onto a different store |
| `MaxRejectedCertificates` normalisation |
`CertificateManagerTests.MaxRejectedCertificatesNormalisesNegativeValues`
|
| `AddRejectedAsync` retention contract |
`RejectedCertificateRetentionTests` — both store types, at zero,
negative and a positive cap |
| PEM rewrite left the old tail behind |
`DirectoryCertificateStoreTests.DeleteFromAMultiCertificatePemFileTruncatesTheFileAsync`
|
| `IsRevokedAsync` threw where CRLs are unsupported |
`CertificateStoreTest.IsRevokedAsyncReportsNotSupportedWithoutCrlSupportAsync`
(runs on Linux/macOS, ignored on Windows) |
| ECC secret left in the caller's buffer |
`EncryptedSecretTests.EccDecryptWipesThePlainTextFromTheCallersBufferOnFailure`
|
| Trust-list read leaked a handle per entry |
`CertificateTrustListHandleTests` |
| A channel that never opened leaked its certificate |
`ClientChannelManagerHandleTests` |
| Chunk ownership, CLO double free, chunk-limit teardown |
`TcpServerChannelBufferTests` (4 new) |
| Receive loop did not follow a replaced transport |
`TcpServerChannelDeterministicTests` (3 new) |
| HTTPS body unbounded, failures unmapped |
`HttpsTransportChannelResponseTests` (5) |
| JSON/OpenAPI endpoints dropped, collapsed, or unordered |
`ServerBaseTransportProfileTests` (12) |
| Channel key ignored the transport profile |
`ClientChannelManagerManagedTests` (2 new) |
| `SelectedUserTokenPolicy` setter always ended at -1 |
`ConfiguredEndpointTests` (4 new) |
| `UpdateExtension` could not delete | `UtilsAdditionalTests` (3 new) |
| A single `LocaleId` was dropped | `SessionLessServiceMessageTests` (2
new) |
| `GetRandomDouble` / typed variant arrays | `DataGeneratorTests` (4
new) |
| `TraceLoggerProvider.IsEnabled` short-circuited every log call |
`TraceLoggerProviderTests` (3 new) |
| A leader never stepped down on an expired lease |
`SharedStoreLeaseElectionTests` (3 new) |
| `FilterEvaluator.InList`, `IsUriHttpRelatedScheme` | existing tests
corrected in the first commit |

**Not covered.** The reconnect hand-over ordering, the OpenSecureChannel
decrypted-buffer returns, the client-side bad-sequence reconnect, the
abort-chunk sizing and the listener closing a blocked socket all need a
two-socket reconnect or a full asymmetric OpenSecureChannel exchange,
which the deterministic channel harness does not model. They are
exercised by the integration suites but not asserted on directly.
## Spec conformance

Where a fix has a normative basis I checked it against the published
specification rather than only against the audit report:

| Change | Reference |
|---|---|
| Every padding filler byte is verified | OPC 10000-6 6.7.2.5.1 — "The
value of each byte of the padding is equal to PaddingSize". The loop
started at `data.Offset` and stopped at `paddingSize`, so on any message
with a header it ran zero times and no filler byte was ever checked. |
| Signature verified before the padding is inspected | OPC 10000-6
6.7.2.5.1 — the signature "includes the headers, all Message data, the
PaddingSize and the Padding"; 6.7.7 — the chunk "shall not be
interpreted until the Message is decrypted and the signature and
sequence number verified". |
| Message-processing errors are logged | OPC 10000-6 6.7.7 — "the
receiver shall log a Bad_SequenceNumberInvalid error", and stacks "shall
have a mechanism to log errors when invalid Messages are discarded". The
handler was an empty method. |
| A bad response sequence number reconnects the channel | OPC 10000-6
6.7.7 — "the receiver shall close the communication channel". It
previously threw into that empty handler and the pending request hung
until timeout. |
| The trust list's own certificates are honoured as peers **and** as
issuers | OPC 10000-4 6.1.3 — "The list of trusted Certificates may
contain a Certificate issued to another Application or it may be a
Certificate belonging to a CA". |
| The abort chunk is sized by the chunk's capacity | OPC 10000-6 6.7.3 —
the abort body is `Error` plus a `Reason` string, so a chunk shorter
than the error body could not carry it. |
| JSON/OpenAPI endpoints are published and match `profileUris` | OPC
10000-4 5.5.4.2 — `profileUris` is the "List of Transport Profile that
the returned Endpoints shall support"; a client asking for the JSON
profile previously got an empty list. |
| RSA-DH peer value restricted to `2 <= y <= p-2` | RFC 7919 5.1, which
the finite-field policies are built on. I found no OPC-specific wording
for this. |

One point where the spec argues against the current shape is called out
in reviewer note 2 below.

### Test runs

On **net10.0**, with `Opc.Ua.Core.Tests` and
`Opc.Ua.Security.Certificates.Tests` also run on **net48**. The
remaining suites were not run on the .NET Framework targets locally, so
that checklist box stays unchecked.

| Suite | Result |
|---|---|
| Opc.Ua.Core.Tests (net10.0) | 4630 passed, 0 failed, 88 skipped |
| Opc.Ua.Core.Tests (net48) | 4545 passed, 0 failed, 104 skipped |
| Opc.Ua.Core.Security.Tests | 556 passed, 0 failed |
| Opc.Ua.Security.Certificates.Tests (net10.0) | 355 passed, 0 failed |
| Opc.Ua.Security.Certificates.Tests (net48) | 353 passed, 0 failed |
| Opc.Ua.Configuration.Tests | 227 passed, 0 failed |
| Opc.Ua.Core.Encoders.Tests | 2929 passed, 0 failed |
| Opc.Ua.Bindings.Https.WebApi.Tests | 346 passed, 0 failed |
| Opc.Ua.Redundancy.Server.Tests | 783 passed, 0 failed |
| Opc.Ua.Client.Tests | 2217 passed, 0 failed |
| Opc.Ua.Server.Tests | 5552 passed, 0 failed |
| Opc.Ua.Sessions.Tests | 778 passed, 0 failed, 379 skipped |
| Opc.Ua.Gds.Tests | 1117 passed, 0 failed |

`Opc.Ua.Sessions.Tests` reports 379 skipped; that is identical to a
`master` baseline run in a separate worktree (security policies the
platform does not advertise), not a regression from this change.

`dotnet format whitespace --verify-no-changes` reports no violations in
any file this PR touches.

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

---------

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
2026-09-14 08:22:41 +02:00
romanett d9efda1d7d Make certificate leak assertions immune to concurrent test activity (#4440)
# Description

`UaSCBinaryClientChannelDeterministicTests` had a concurrency bug that
made the **full** `Opc.Ua.Core.Tests` suite fail on master (e8bec27d5),
while the fixture passed 25/25 when run filtered.

```
dotnet test tests/Opc.Ua.Core.Tests/Opc.Ua.Core.Tests.csproj -p:CustomTestTarget=net10.0
=> Failed: 1, Passed: 4391, Skipped: 86, Total: 4478
=> ReadAsymmetricMessageHeaderDisposesSenderChainWhenReceiverCertificateMissing
   Assert.That(Certificate.InstancesCreated - createdBefore,
               Is.EqualTo(Certificate.InstancesDisposed - disposedBefore))
   Expected: 1  But was: 2
```

**Cause.** The three `ReadAsymmetricMessageHeaderDisposesSenderChain*`
tests took a baseline of `Certificate.InstancesCreated` /
`InstancesDisposed` — static, process-wide counters — ran one parse,
then asserted the two deltas were equal. The fixture is
`[Parallelizable]`, so any certificate a concurrently running test
allocated inside the measured window inflated the created delta without
a matching dispose. Which test lost the race varied by environment
(locally `...WhenReceiverCertificateMissing`, on GitHub Actions
`test-ubuntu-latest-Core` the sibling
`...WhenReceiverThumbprintMismatches`), which is itself evidence of a
race rather than a product defect. The product path is fine — the
assertion passes whenever the window is uncontended.

**Fix.** Observe the exact handles the header parser allocated rather
than global counters. `ReadAsymmetricMessageHeader` disposes the sender
chain *and* clears the `out` parameter when validation fails, so the
chain is unreachable from the caller; an `internal
SenderCertificateChainParsedForTest` hook now surfaces it the moment it
is parsed. It is reachable through the existing `InternalsVisibleTo
Opc.Ua.Core.Tests` and follows the `IsHeldBySomeContextForTest`
precedent in `ChannelGate`.

The tests snapshot those handles — a copy without `AddRef`, since a
disposed `CertificateCollection` clears itself and throws on enumeration
— and probe each one with `AddRef()`, the only observable that
distinguishes a released core from a live one. The probe handle is
disposed immediately, so the refcount is untouched. Non-null and
non-empty assertions guard against a vacuous pass. The fixture stays
`[Parallelizable]`; `[NonParallelizable]` was rejected as it only
narrows the window and costs suite time.

## Audit of the other counter readers

| Site | Status |
| --- | --- |
|
`CertificateValidationHelpersTests.ConstructionFailureDisposesAlreadyBuiltCertificates`
| **Converted.** It asserted an *absolute* `created - before == 1`. Its
own factory delegate builds the instances, so it now tracks them
directly — no product change needed. |
| `CertificateManagerTests` (`GetIssuersAsync`) | Left as-is. Already
`[NonParallelizable]` on the test; the window spans a whole trust-list
resolve, where instance capture isn't practical. |
|
`UaSCBinaryLoopbackTests.FailedReconnectDisposesCandidateCertificateHandlesAsync`
| Left as-is. Fixture is `[NonParallelizable]`; measures a full TCP
reconnect. |
| `TrustedIssuerStoreResolverTests` (PubSub.Mqtt) | Left as-is. No
`[Parallelizable]` on the fixture and no assembly-level attribute, so it
runs in NUnit's non-parallel shift. |
| `LeakDetectionSetup` | Left as-is. Assembly-level teardown, where the
global counters are the correct observable. |

## Verification

- **Three full (unfiltered) `Opc.Ua.Core.Tests` runs on net10.0: 0
failed, 4392 passed, 86 skipped, 4478 total** — one more pass than the
4391 on master. A filtered run cannot reproduce this failure, so the
full suite is the only meaningful check.
- **Negative control:** temporarily removing the product's
`senderCertificateChain?.Dispose()` failed all three tests with
`Expected: True, But was: False`, then reverted. The new assertions
still detect a genuine leak.
- Not run locally: the full **UA.slnx** solution against .NET Framework.
Leaving that to CI.

## Related Issues

No tracked issue — this is a test-infrastructure fix for a failure
observed on master and in the `test-ubuntu-latest-Core` CI job.

## Checklist

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
_(Opc.Ua.Core.Tests on net10.0 only — see Verification.)_
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

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

---------

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
2026-09-07 22:57:43 +00:00
romanett f96ca6df0b Enforce trust-material changes on live channels regardless of origin (#4357)
## Proposed changes

When a CRL (or any other trust-material change) reaches the server,
connected clients whose certificates it revokes should be disconnected
immediately — not at their next security-token renewal (default lifetime
1 h). The `ApplyChanges` push path already ran the OPC 10000-12 §7.10.9
sweep, but three gaps kept a revoked client connected:

1. **The push path never invalidated the validator.** `TrustList` writes
certificates/CRLs directly to the stores;
`CertificateManager.NotifyTrustListChanged` (the only thing that drops
the cached validation cores) was never called. Freshness relied on the
directory store's `(name, length, mtime)` + 30 s cache heuristic, which
non-directory `ICertificateStore` implementations don't even guarantee.
Worse: with `SecurityConfiguration.UseValidatedCertificates = true`, the
thumbprint fast path returned **before the revocation check**, so a
pushed CRL was never enforced at all for a previously-seen client — not
at renewal, not even on a fresh channel.
2. **Out-of-band changes had no server-side consumer.**
`CertificateChangeKind.TrustListUpdated`/`CrlUpdated` (raised by
`WriteTrustListAsync`, `ITrustListTransaction` commits, HA shared-store
sync) were only observed by the client-side `ManagedSession`;
enforcement waited for the token renewal.
3. The legacy non-transactional `TrustList` (immediate apply,
`applyChangesRequired = false`) ran no effects at all.

### Changes

- `NotifyTrustListChanged` is now part of `ICertificateTrustListManager`
(public on `CertificateManager`). The `ApplyChanges` deferred apply
calls it for every committed scope after the response boundary and
**before** the §7.10.9 sweep, so the sweep provably observes the
committed stores. The legacy `TrustList` gets the same via an opt-in
`SetTrustListChangeNotifier`.
- The `UseValidatedCertificates` fast path in
`CertificateValidationCore` moved after the issuer walk: revocation is
always evaluated; a clean cache hit still skips the expensive chain
build (the performance intent is preserved, the security hole is not).
- New internal `CertificateChangePump<TState>`, extracted from
`ClientChannelManagerCertRotation` (which now runs on it, behavior
unchanged), coalesces `CertificateChanges` events.
`ConfigurationNodeManager` subscribes a scope-union pump so **any**
`TrustListUpdated`/`CrlUpdated` — whatever wrote the stores — triggers
the same `IPushConfigurationTrustListEffectHandler` fan-out. Self-raised
notifications are suppressed, so a push still runs exactly one sweep.
Session semantics are unchanged: peer revocation cuts only the
SecureChannel; only user-token-group changes close Sessions
(+Subscriptions).
- The per-group store identifiers preserve the configured `StoreType`
instead of re-inferring it from the path (fixes pushing through a
different store implementation than the validator reads for custom
providers, e.g. HA shared key-value stores).
- Integrated the caller-owned `CertificateStoreIdentifier.OpenStore`
contract from #4382: `TrustList` lazily holds its trusted/issuer store
instances for its lifetime, `ConfigurationNodeManager` owns its
rejected-store instance, and both node managers dispose the handlers
they own. This replaces the former interim identifier-cache cleanup
while keeping the shutdown leak gate clean.

### Behavior notes

- A server that previously kept revoked clients connected until token
renewal now cuts them as soon as an out-of-band CRL lands. Re-validation
failures fail open (a channel whose trust cannot be determined stays
open), and closed-channel counts are logged.
- Hosts using `UseValidatedCertificates` for throughput keep the
chain-build saving but lose a revocation-check skip they should never
have had.
- A bare file copied into a store directory raises no event and is still
only picked up at the next validation (bounded by the 30 s directory
cache for new channels).

### Tests

- `PushTest.PushedCrlDisconnectsRevokedClientAsync` — end-to-end: a
client with a CA-issued certificate connects, a CRL revoking it is
pushed via `CloseAndUpdate` + `ApplyChanges`, the server cuts its
channel right after the response and refuses its reconnects; the
unaffected admin client stays connected; trust material is restored
afterwards.
- `ConfigurationNodeManagerTrustListEffectsTests` — live-validator
enforcement after a pushed CRL, out-of-band pump dispatch per scope,
scope→effect mapping, store-type preservation.
-
`CertificateValidationCoreTests.ValidatedCertificateFastPathDoesNotSkipRevocationAsync`
— fails without the fast-path fix.
- `CertificateChangePumpTests` — coalescing, drain-until-empty, error
resilience, dispose semantics.
- `TrustListTests` — legacy notifier flags for
`CloseAndUpdate`/`AddCertificate`/`RemoveCertificate`.

Suites run locally (net10.0): GDS PushTest 314/314 (leak detector
clean), Server.Tests configuration/trust/push 416/416, Core.Tests
certificate/channel 556/556, Client.Tests 2161/2161; net48 build clean.

## Types of changes

- [x] Bugfix (non-breaking change which fixes an issue)
- [x] Enhancement (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation Update (if none of the other choices apply)

## Checklist

- [x] I have read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf).
- [x] I ran tests locally with my changes.
- [x] I have added tests that prove my fix is effective or that my
feature works.
- [x] I have added necessary documentation (if appropriate).

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

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Co-authored-by: Marc <marcschier@hotmail.com>
Copilot-Session: d043dc7d-5c08-4084-96be-1f64e5466525
2026-09-02 12:12:55 +00:00
romanett 6e791517b5 Make CertificateStoreIdentifier a pure store description (#4382)
### Why

Follows up on the [review discussion in
#4357](https://github.com/OPCFoundation/UA-.NETStandard/pull/4357#discussion_r3903422013):
the rule in this codebase is *if you get handed an IDisposable, it is
your responsibility to dispose it*, but
`CertificateStoreIdentifier.OpenStore` handed every caller the **one**
store instance cached on the identifier. A caller honoring the rule
disposed shared state other holders of the same identifier were still
using (it only appeared to work because the store implementations
tolerate use after dispose), while a caller that only called `Close()`
left the cached instance — and its parsed-certificate cache — alive with
no owner, which is exactly what the certificate leak gates flag at suite
end.

### What

Of the two options discussed (caller-owned instance vs. a new
ref-counted wrapper type), this implements the simpler one, modeled on
the existing `CertificateIdentifier` / `Certificate` pair:

- `CertificateStoreIdentifier` is now a pure **description** of a store,
exactly like `CertificateIdentifier` is for a certificate. It caches
nothing and has no disposable-like lifecycle.
- `OpenStore` creates and opens a **new instance on every call**, which
the caller owns and must dispose — like a resolved `Certificate`. If
`Open` throws, the instance is disposed before the exception propagates.
- Components that access a store repeatedly keep their instance open for
as long as they need it instead of relying on identifier-level caching:
the certificate validator already does this via its per-core store cache
(`CertificateValidationCore.m_stores`), which now also disposes the
loser of its benign `GetOrAdd` race instead of leaking it.
- Call sites that relied on the shared cached instance by only calling
`Close()` now dispose the store they own:
`CertificateTrustList.GetCertificatesAsync`, `SecurityConfiguration`
store validation, both `X509Utils` store extensions, the server
`TrustList` store-update helpers and the rejected-certificate list read.
- New `CertificateStoreIdentifierOpenStoreTests` pin the ownership
contract (independent instance per call, disposing one instance does not
affect another, empty path returns null).

A ref-counted wrapper prototype was implemented and discarded: it forced
every short-lived identifier creation site (~20 in src, more in tests)
to release a hidden base reference, spreading the disposable-like
lifecycle the review objected to across the whole codebase instead of
removing it.

### Verified

Release, `net10.0`, with `OPCUA_CERTIFICATE_LEAK_TRACKING=1`:
- Opc.Ua.Core.Tests: 4376 passed
- Opc.Ua.Configuration.Tests: 227 passed
- Opc.Ua.Server.Tests: 4797 passed
- Opc.Ua.Gds.Tests: 1111 passed
- Opc.Ua.Client.Tests (full suite): 2164 passed
- Opc.Ua.Core.Security.Tests: 556 passed
- Opc.Ua.PubSub.Mqtt.Tests: 157 passed (its strict certificate
instance-count test passes unmodified under the new contract)
- Opc.Ua.Tools.Tests: 710 passed

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

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
2026-09-02 10:43:13 +02:00
romanett a504c3e248 Fix certificate leak when rejected-store enqueue races manager disposal (#4337)
The macOS legs of the Build and Test workflow intermittently failed the
assembly-level teardown of the Sessions (also History and Client) test
suites with "Certificate leak detected: 1 instance(s) created but not
disposed" while every test passed (master run 33004556144:
created=16777, disposed=16776; PR run 33207357247: created=17373,
disposed=17372). The count held steady through the teardown's full
quiescence window, so the missing disposal was permanent, not a slow
in-flight drain.

RejectedCertificateProcessor.EnqueueAsync takes a per-certificate AddRef
for the queued WriteRequest before TryWrite. Once
CertificateManager.DisposeAsync has completed the channel writer, the
bounded DropOldest channel refuses TryWrite and the WriteAsync fallback
throws ChannelClosedException, abandoning the request: nothing releases
the references it owns, so every certificate in the chain keeps one
leaked reference for the life of the process. A validation that races
manager disposal — a keep-alive, reconnect or fire-and-forget channel
teardown rejecting a certificate while the fixture tears down — lands in
exactly this window, and the slower loaded macOS runners make that race
likely. The abandoned request also left FlushRejectedAsync waiters
hanging on a drain marker that never resolves, and surfaced unobserved
ChannelClosedExceptions through the fire-and-forget
EnqueueRejectedCertificate discard.

Route both enqueue paths through a fallback that, when the write cannot
commit the request to the channel, disposes the request's chain
(releasing the per-certificate references), resolves its completion as
"not processed" so drain waiters are unblocked, and swallows only the
benign ChannelClosedException shutdown race; cancellation still
propagates. The teardown leak detector needs no change: its quiescence
poll was correctly reporting a genuine leak.

The new regression test reproduces the CI signature deterministically
against the previous code (ChannelClosedException plus "Certificate leak
detected: 1 instance(s) created but not disposed (created=1,
disposed=0)" in the assembly teardown) and passes with the fix.

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
2026-08-29 10:30:19 +02:00
Copilot ca9cfcc933 Inject ISecurityPolicyRegistry into Session and secure channel (#4314)
- [x] `ChannelQuotas` + `UaSCUaBinaryChannel` carry an
`ISecurityPolicyRegistry` (falling back to `SecurityPolicies.Default`)
- [x] Transport channel/listener settings carry the registry and feed
every `ChannelQuotas` construction site
- [x] `ClientChannelManager` and `ServerBase` source the registry
- [x] `Session`, `DefaultSessionFactory`, `ChannelManagerSessionFactory`
and `ManagedSession` carry it
- [x] Identity token handler injection points made load-bearing
(`UserIdentity`, `AsTokenHandler`, default identity providers,
`IdentitySelectionContext`)
- [x] `SessionSecurityPolicyHelper`, `ClientIdentityProviderExtensions`,
`CoreClientUtils`, `OfflineSecureChannel`,
`OpcUaSecurityKeyServiceClient`
- [x] Client and server DI wiring resolve `ISecurityPolicyRegistry`
- [x] `IPubSubSecurityPolicyRegistry` registered in DI and threaded
through the PubSub application/SKS paths
- [x] Channel asymmetric crypto (padding, sign, verify, ECC
classification) resolves from the negotiated policy instead of a
hard-coded policy URI switch
- [x] Unit tests for the registry carriers plus an integration test that
negotiates a policy registered through `AddSecurityPolicy` over a real
loopback handshake
- [x] `docs/CryptoProvider.md` documents how the registry reaches the
channel and the session
- [x] Full solution build (`UA.slnx`, net10.0) and full
`Opc.Ua.Core.Tests` run (4351 passed) are green
- [ ] Broader integration suites (`Opc.Ua.Sessions.Tests`,
`Opc.Ua.Server.Tests`, `Opc.Ua.PubSub.Tests`) were still running when
time ran out

- [x] Review feedback addressed: preserved original CLR signatures,
routed factory channel creation through public registry-aware overloads,
failed closed for unsupported asymmetric encryption, and added a
provider contract for custom session factories
- [x] Focused review-feedback tests pass (28 tests across Client, Core,
and Core.Diagnostics)

- [x] Security review: hardened SKS custom-policy admission against weak
algorithms and incoherent RSA/ECC key-exchange metadata; final
specialist review found no remaining vulnerabilities

<!-- START COPILOT CODING AGENT SUFFIX -->

- Fixes #4250

---------

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 <mschier@microsoft.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: romanett <romanett98@gmail.com>
2026-08-27 05:57:17 +02:00
Marc Schier aad8350bc1 Pluggable symmetric cryptography, an awaitable asymmetric path, registrable security policies, and PubSub crypto offboarding (#4206, #4207, #4208, #4210) (#4232)
# Description

Closes the three crypto-offboarding follow-ups split out of #4192. Each
was recorded there as knowingly *not* done, with the reason and what
would justify revisiting it. Those conditions are met, and where one of
them turned out to be unachievable that is written down rather than
worked around.

The safety property throughout: **every seam is opt-in and null-checked,
and in the default software configuration the added code is observably
inert.** No interface dispatch on the per-message path, and the
asynchronous paths complete synchronously — so channel locking order,
buffer ownership and error sequencing are unchanged for a deployment
that configures nothing.

## #4207 — symmetric, key-derivation and RNG provider seams

`ISymmetricCryptoProvider`, `IKeyDerivationProvider` and
`ISecureRandomSource`, added on the terms #4207 set: only once a
concrete requirement arrived (a validated module that must perform
*every* operation, not just the asymmetric ones), behind a fast path,
with `SymmetricChannelCryptoBenchmarks` as the gate.

They are **facets discovered by type test**, not members of
`ICryptoProvider`, so providers written against the shipped interface
still compile. `PlatformCryptoProvider` implements all three, which
answers the "an interface nothing implements" objection recorded in the
issue.

`CryptoProviderFacets` returns `null` both when no registry is
configured *and* when resolution lands on the platform, because the
platform facets are the inline code. Resolution happens once, in
`CalculateSymmetricKeySizes`, and is held for the life of the channel.

`CryptoCompliance.GetUnservedOperationPurposes` closes the failure the
seam would otherwise introduce: a provider bound to `ChannelSymmetric`
without implementing the facet is silently replaced by the platform, so
a deployment could believe its validated module performed the
per-message cryptography while the platform did. Under `FipsOnly` that
now refuses to start.

## #4208 — the asymmetric path is awaitable

`RSA` and `ECDsa` are .NET's contracts and cannot be replaced without
making every ready-made hardware and cloud implementation unusable.
Instead an implementation may **also** declare `IAsyncRsaKey` /
`IAsyncEcdsaKey`, which the stack finds by type test.

Now asynchronous: the secure channel open and renew path, user identity
token signing and decryption, and session activation. A software key
declares neither facet, so those paths complete synchronously and
nothing about their ordering changes.

`ReadAsymmetricMessage` is refactored into shared helpers rather than
duplicated — adding an `await` was not worth two hundred cloned lines of
signature, padding and endpoint-selection logic. `AsymmetricMessage` /
`AsymmetricWriteResult` exist because an asynchronous method cannot have
`out` parameters.

The channel no longer serialises its state on a monitor. A monitor
cannot be held across an `await`, and a plain `SemaphoreSlim` was not an
option at the time: the code relied on re-entrancy in eight places
(`HandleIncomingMessage` holds the lock and calls `ForceChannelFault`,
which takes it again; `ForceReconnect` and `Shutdown` do the same).
`ChannelGate` replaces it at 32 sites and `DataLock` is `[Obsolete]`.
That reliance has since been removed as well — see [Removing the gate's
re-entrancy](#removing-the-gates-re-entrancy) below.

### Defects this surfaced, all fixed and regression-tested

**Detached work started inline.** Writes were started with `_ =
WriteBuffersAsync(...)`. An async method runs its prologue on the
caller's stack, so `LeaveInheritedContext` — which exists to stop
*detached* work inheriting the right to re-enter the gate — was
stripping the **caller's own** entitlement; when the send then completed
synchronously, the completion blocked on a gate that very thread was
holding. The client sent its OpenSecureChannel request and never
processed the response. Writes are now queued.

**A synchronous gate handle held across an `await`.** `Enter()` records
the acquiring thread so an inline completion callback can re-enter —
`ChannelAsyncOperation` invokes its callback both inline and detached.
That record is only sound while the holder is synchronously on that
thread; the token renewal path held it across an await, so a reused pool
thread was recognised as the holder.

**`SignAsync` rejected the policy that signs nothing.** It validated the
certificate before the algorithm, so `SecurityPolicies.None` — which
carries no certificate — threw where the synchronous `Sign` returns
`null`.

**`EnterAsync` lost the holder when contended** *(found in review)*. The
`AsyncLocal` recording ownership was written inside the awaiting method,
and .NET restores the caller's execution context when an async method
completes, so the write was discarded. The caller returned owning the
semaphore while `IsHeldByCurrentContext` reported `false` — and any
nested `Enter()` then blocked forever on a gate its own context held.
Reachable remotely: `HandleIncomingMessageAsync` → error path →
`ForceChannelFault`. The holder is now published from the caller's frame
before the wait, and only its depth is raised in the continuation.

**Queued writes lost their order** *(found in review)*. Sequence numbers
are assigned under the gate, but independently queued work items reach
the transport's FIFO send lock in arbitrary order, so a peer could
reject a chunk with `BadSequenceNumberInvalid`. Writes are now appended
to a chain: still off the caller's stack, but a write cannot start
before its predecessor finishes.

### Four more this surfaced in CI, on paths only the integration suites
reach

Queuing the writes to fix the deadlock above turned out to have moved
three implicit guarantees, and the gate had one more liveness bug. Each
was reproduced locally against a clean baseline before it was changed.

**A faulting channel's error message never reached the peer.** A
listener channel sends a UASC `Error` describing why it faulted and
closes the transport as its next statement. That worked only because the
write started on the caller's stack, so the bytes reached the socket
first; queued, the close discarded them and the client saw
`BadConnectionClosed` instead of the certificate status it was told to
expect. Nine `SecurityCertValidationTests` cases assert exactly that
status. The terminal error is written inline again, on a path that
touches the gate only to disclaim what it inherited and reports nothing
— a channel that is already faulted is owed nothing beyond its buffer.

**The certificate of a rejected sender leaked.** An asynchronous method
cannot have `out` parameters, so the asymmetric read returns a record
instead. That silently dropped an ownership guarantee: an `out`
parameter reaches the caller even when the method goes on to throw, so
the caller's `catch` disposed the sender certificate and reported it to
the audit. A return value does not — nine leaked certificates, one per
rejection case, which the leak detector fails the run on. The parsed
certificate is now handed to the caller before anything that can reject
the message, restoring both the disposal and the audit.

**The gate could strand its own permit.** It released only when the
holder's depth returned to zero, but that depth lives in an `AsyncLocal`
and is therefore shared with every context forked from the owner's — a
timer callback whose timer was created inside the region, for instance.
Such a context entering the gate raised the shared depth, so the owner's
own exit saw a non-zero depth and returned without releasing, and
nothing afterwards could: the nested exit is not the owner. Every later
entry on that channel blocked forever. `Opc.Ua.Features.Tests` hung
after its tests had finished, with a receive loop waiting on the gate
and the server unable to stop. The owner now releases when it leaves;
depth still gates re-entrancy, but liveness no longer depends on a count
another context can move.

**Write completion throttled the writer.** Reporting a completed write
sat inside the ordering chain, and the client channel implements that
callback by entering the gate — so every write queued behind a gate the
receive loop contends for on each incoming chunk. A session with fifty
subscriptions publishing continuously had its publish requests throttled
enough that the client kept topping them up past its own limit, which
`Subscriptions.Classic` asserts against. Completion is now reported off
the chain, which covers only what ordering actually requires.

### Still synchronous, and why

Certificate, certificate request and revocation list signing cannot be
made asynchronous at all: `X509SignatureGenerator.SignData` is invoked
by .NET's own builders. Service faults and the `Reconnect` override are
reached from synchronous call sites (`SendServiceFault` alone has eight)
and are left as they are behind scoped, commented suppressions. All
three are documented rather than left to be rediscovered.

## #4210 — PubSub

This one produced a finding rather than the API the issue asked for, and
the finding is the point:

> **With a standard Security Key Service the key necessarily exists in
process memory.** `GetSecurityKeys` (Part 14 §8.3.2) returns raw key
bytes over the wire, so the "key never leaves the device" property #4192
achieved for client and server **cannot** be achieved for PubSub through
the SKS pull profile. That is a property of the specification, not of
this stack.

A wrapped-key envelope would change what is on the wire and break
interoperability with third-party key services and publishers, so it was
rejected rather than built.

What is achievable is delivered: the per-message AES-CTR and HMAC route
through `ISymmetricCryptoProvider`, so a validated module performs them.
`IPubSubSecurityPolicy` is **not** modified — new members would break
every implementation of it; the provider is supplied through the policy
constructor. `PlatformSymmetricCryptoProvider` gained AES counter mode,
which the seam should have covered anyway since the algorithm enum names
it.

Key lifetime is also tightened: unpacking an SKS response copied key
material into intermediates that `ByteString.Create` then copied again,
leaving plain keys in the heap for the lifetime of the process. Those
are now zeroed.

### Two wiring gaps this depended on, both found in review

The registrations above were **inert**, so this section originally
claimed more than the code did:

- `CryptoProviderConfiguration` was applied nowhere outside tests, so
`AddCryptoProvider(configure)` never reached the registry in a real
host. The registry now applies every registered configuration when it is
first resolved — which also affects #4207's DI story.
- `PubSubSecurityWrapperResolver` selected
`PubSubAes256CtrPolicy.Instance`, the provider-less static singleton,
ignoring the provider-backed bundles registered for it. A `FipsOnly`
deployment therefore certified while the platform did the work. The
resolver now selects from the registered policies; the container and
`PubSubApplicationBuilder` both supply theirs.

A third, smaller one: `CryptoProviderBuilder.Use` published a
**policy-scoped** random source as the process-wide nonce source, so
`.For(purpose, policyUri).Use(hsm)` redirected nonce generation for
every other policy too. Only an unscoped binding does that now.

## #4206 — a provider can contribute a security policy

Added in review: the policy set was fixed at compile time, so a provider
could contribute key custody but not a *profile*. It is now table-driven
and open, and the blockers #4206 listed are gone.

```csharp
using IDisposable registration = SecurityPolicies.Register(
    new SecurityPolicyInfo("urn:vendor:SecurityPolicy#CustomProfile", "CustomProfile")
    {
        PlatformSupport = () => true,
        SupportedCertificateTypes = [ObjectTypeIds.RsaSha256ApplicationCertificateType],
        IsDefault = true
    });

services.AddOpcUa()
    .AddCryptoProvider(crypto => crypto
        .For(CryptoPurpose.ChannelSymmetric, "urn:vendor:SecurityPolicy#CustomProfile").Use(module))
    .AddSecurityPolicy(customPolicy);
```

- **The reflection is gone.** Four lookup tables were built by
reflecting over the fields of `SecurityPolicies` and
`SecurityPolicyInfo`. They are one explicit table now, which removes the
**last reflection in `Security/Constants`** — so this is a trimming and
Native AOT improvement as much as a feature.
- **`SecurityPolicyInfo` is constructible from another assembly** and
carries the metadata the helpers need, so `IsPlatformSupportedName`,
`GetDefaultUris`, `MapSecurityPolicyToCertificateTypes` and
`GetCurveFromCertificateTypeId` read that table instead of each being
hand-written. Adding a policy is one entry rather than five edits.
- **The dead `#if CURVE25519` conditional is deleted** from
`Security/Constants`.
- Registration is copy-on-write, so the read path stays lock-free.
Shadowing a built-in policy requires `replaceExisting: true` and is
reversible by disposing the registration.

`RegisterLightsUpCurvePoliciesFromOutsideCore` is the acceptance test
the issue asked for: it registers `ECC_curve25519` and `ECC_curve448`
from the test project and asserts they become discoverable through the
public API.

**Registering a policy makes it advertised and resolvable; it does not
supply the cryptography behind it.** For those two curve profiles the
in-tree key agreement is still behind a compile symbol no project
defines plus a BouncyCastle dependency, so a deployment lighting them up
provides the operations through a provider. That division is the point:
the policy set says *what* is offered, the provider says *who* performs
it.

## Removing the gate's re-entrancy

Folded in from #4242, which was merged into this branch.

`ChannelGate` was re-entrant, and that forced the design behind most of
the defects above. A holder that awaits releases its thread, so
ownership could not be tracked by thread identity — it had to live in an
`AsyncLocal<Holder?>`. A logical context is *inherited*, so anything
started while the gate was held inherited the right to re-enter and ran
inside the guarded region alongside whatever started it, unless it opted
out by hand via `LeaveInheritedContext()` at each of eight sites,
enforced by review alone. Five of the defects listed above trace to that
mechanism, including both CI hangs.

So the *requirement* was removed rather than the mechanism, and the
`AsyncLocal` then deleted itself. Every path that re-entered now calls a
lock-free `Core` method (`ForceChannelFaultCore`, `ShutdownCore`,
`ForceReconnectCore`, `CompleteConnectCore`), and three regions stopped
running foreign code under the lock: the `RequestReceived` dispatch is
deferred until the gate is released, `OnTransportError` no longer wraps
the `HandleSocketError` virtual, and the callback setters and
`EndpointDescription` publish a single reference with a volatile write
instead of locking — the last is load-bearing, because
`AsyncResultBase.OperationCompleted` invokes the reverse-hello callback
inline while the gate is held.

`ChannelGate` is now a `SemaphoreSlim(1,1)` behind a `Releaser`;
`Holder`, the thread-identity fallback, `LeaveInheritedContext`,
`IsHeldByCurrentContext` and all eight disclaimer calls are gone, with
the call shape at all 32 sites unchanged. `SaveIntermediateChunk`,
`GetSavedChunks` and `DoMessageLimitsExceeded` gained a `gateHeld`
argument, because the client reaches them both with and without the gate
and must pick the matching teardown — without it an oversized
`OpenSecureChannel` response deadlocked the receive loop against itself.

The remaining paths were not found by reading the code, since that is
what missed them originally. A temporary strict mode made every
re-entrant acquisition throw with its stack, the suite was run under it
until clean, and it was deleted with the re-entrancy it measured. It
caught two sites review had missed: the `EndpointDescription` **property
getter** taking the gate, and the `RequestReceived` dispatch to
application code happening inside the guarded region.

Two deliberate residuals are documented for reviewers: `Dispose` no
longer takes the gate (unavoidable — it is reached from `ChannelFaulted`
with the gate held, where the old re-entrant acquisition excluded
nothing anyway), and the deferred request dispatch builds
`SecureChannelContext` just after gate release rather than under it.

## Testing

New: the three seams and their platform implementations, facet discovery
and resolution precedence, `FipsOnly` refusing a provider that cannot
serve what it was bound to, AES counter mode (including a
non-block-aligned round trip and a check that the counter carries, since
one that did not would silently reuse key stream), `ChannelGate`
(exclusion, re-entrancy across an await, re-entrancy on a reused thread,
and the deadlocks above), the asynchronous channel paths, and the PubSub
policy provider.

Each review finding got a test that fails without its fix:

- `ContendedEntryStillRecordsTheHolderAsync` — established contention
deterministically, then re-entered; failed on the pre-fix gate. Removed
with the re-entrancy it covered; `ChannelGateTests` now asserts the
non-re-entrant contract instead.
- `SecureClientAndTcpListenerKeepChunkOrderUnderConcurrentRequestsAsync`
— 60 concurrent multi-chunk `SignAndEncrypt` requests over a real
loopback listener; failed 3 runs out of 3 with the previous dispatch,
passes 3 out of 3 with the chain.
-
`DependencyInjectionRoutesPubSubCryptoThroughTheRegisteredProviderAsync`
— builds a container, registers a counting provider, wraps a message and
asserts the provider actually performed the encryption and the
signature. This is the assertion the PubSub claim above now rests on.
- `PolicyScopedRandomBindingDoesNotEscapeItsPolicy`.

Two further assertions are the ones that would catch a silent defect: a
provider and the platform must produce **byte-identical** output — a
validated module that disagreed could not interoperate — and with a
software key the returned `ValueTask` must report
`IsCompletedSuccessfully`, which is what makes "ordering is unchanged"
checkable rather than merely asserted.

`SymmetricChannelCryptoBenchmarks` gains a provider-registered variant
beside the existing baseline, so the cost of the indirection is measured
rather than assumed.

Verified locally, every suite at or above its recorded baseline: `dotnet
build UA.slnx -c Release` **0 warnings, 0 errors on all six target
frameworks**; Core **4413** (net10.0); Core.Security **617**, with its
certificate-leak detector clean; PubSub **1350** plus PubSub.Diagnostics
**54** and PubSub.Udp **233**; Features **156**; Subscriptions.Classic
**32**; Server integration **4053**; Client integration **2123**;
MigrationAnalyzer **151** and MigrationAnalyzer.Core **13**. Zero
failures in each.

Core moved from 4388 to 4381 when the gate change landed — eight
re-entrancy tests were removed along with the behaviour they covered,
and one deadlock regression test added — and has since grown to 4413
with the registry isolation, provider-output and security-review tests.
`ChannelGateTests` was rewritten around the new contract — exclusion
across both entry modes, an uncontended asynchronous entry not
suspending, re-entry blocking by contract, and the property that used to
be the hazard: work started while the gate is held is excluded without
having to opt out.

Every CI failure this PR produced was reproduced locally, diagnosed
against a clean `origin/master` baseline in a second worktree, and fixed
at the source. Two hangs were found from `--blame-hang-timeout` dumps
read with `dotnet-dump`. One failure that looked like a candidate was
confirmed **not** to be: an intermittent `Opc.Ua.Aot.Tests` connect
failure, pre-existing on `origin/master` (5 of 8 baseline runs failed,
versus 3 of 14 here).

### The publish request overshoot

`Subscriptions.Classic.PublishRequestCountAsync` failed on the Windows
net10.0 leg with **207** outstanding publish requests against a cap of
`max(maxServerPublishRequest, subscriptions)` = 50. It failed in 2 of 6
pipeline builds on this branch, never on `master` in 13 sampled builds,
and never locally in 12 attempts including under deliberate CPU
contention.

The mechanism is a genuine race.
`ClassicSubscriptionEngine.QueueBeginPublish` was a **check-then-act**:
it read `GoodPublishRequestCount`, compared it against
`GetDesiredPublishRequestCount(false)`, and issued a publish if it was
below. It runs on every publish completion, so *n* completions that
overlap each read the same value, each conclude they are below the cap,
and each issue — overshooting by up to *n* per round. The read also
*lags*: a request only becomes visible to `GoodPublishRequestCount` once
`AsyncRequestStarted` has recorded it, which happens after the request
has already been sent.

That code is pre-existing and was untouched by this PR. What this PR
changed is how hard the race is hit: the server used to hold the channel
gate across request processing, which serialised every request on a
channel, so publish completions arrived one at a time. Dispatching
`RequestReceived` outside the gate — an intended improvement, since a
channel should not serialise on application request-processing time —
lets them complete concurrently.

Rather than change the publish pipeline blind, the race was first made
reproducible.
`ConcurrentPublishReEvaluationDoesNotExceedDesiredRequestCount` drives
64 barrier-released completions against a mocked context whose count
lags the send exactly the way the session's does. It issued **64
requests where 5 were desired** — the same defect the CI leg hit, now
deterministic and running in milliseconds.

The engine now tracks the requests it has in flight and reserves a slot
with a compare-exchange before sending, so the decision and the send are
one atomic step. The reservation is released when the request completes,
when the send is declined, or when it throws. The repro test then issues
at most the desired count.

`StartPublishing` is deliberately left **uncapped**. It is the recovery
valve that refills a pipeline whose requests are outstanding but no
longer expected to return, so gating it on the in-flight count would
remove the only path out of a stalled pipeline. An earlier revision of
this fix did gate it, and that is the one change here that could not be
justified on the evidence — it was reverted.

The assertion was **not** loosened, retried away, or marked flaky: it
caught a real throttling regression earlier in this PR and is worth
keeping sharp.

Validated: the repro test red before the fix and green after;
`Subscriptions.Classic` 32/32 **five** consecutive runs on net10.0 and
once on net48; `Opc.Ua.Client.Tests` 2124 on net10.0 across four
consecutive runs and 2127 on net48; `Opc.Ua.Subscriptions.Tests` 604
passed with this fix in place.

### The SSH.NET advisory that turned CI red repo-wide

Partway through this work every build job began failing with `NU1903:
Package 'SSH.NET' 2025.1.0 has a known high severity vulnerability`
([GHSA-q939-rpr3-3284](https://github.com/advisories/GHSA-q939-rpr3-3284),
`<= 2025.1.0` affected, first patched `2026.0.0`).

Nothing in the dependency graph changed — the advisory was published.
Build 17026 failed on it where build 17000, two hours earlier on an
identical graph, had passed every build job. SSH.NET is not referenced
anywhere in the repository; it arrives transitively through
`Testcontainers.Kafka`.

`master` landed the remediation independently while this was being
investigated (a central transitive pin to `2026.0.0`, which
`CentralPackageTransitivePinningEnabled` exists for). This branch
briefly carried its own identical pin, which made the merge commit hold
**two** `PackageVersion` entries for SSH.NET and fail restore with
`NU1506`. The duplicate is removed and `master` is merged, so the pin
now comes from one place only.

The audit was **not** suppressed: `NuGetAudit` stays enabled and
`NU1903` stays an error. Verified after the merge — `dotnet restore
UA.slnx` reports neither NU1903 nor NU1506, and `dotnet build UA.slnx -c
Release` is **0 warnings, 0 errors** with the audit live.

The remaining red check in build 17026 was not from this change either.
`aot-ubuntu-latest` is the intermittent `Opc.Ua.Aot.Tests` failure
already noted above — `ReconnectSessionAsync` timed out at 30s with 135
of 136 passing. It remains below the `origin/master` baseline rate (4 of
15 sampled here against 5 of 8 on the baseline), and the managed
reconnect paths are green throughout: `Opc.Ua.Client.Tests` 2124 across
four consecutive runs and `Opc.Ua.Subscriptions.Tests` 604.


## Documentation

`docs/CryptoProvider.md` gains sections on substituting the symmetric
primitives, using a key served over a network, and PubSub — including
what cannot be claimed and why, the scope rule for a random-source
binding, and how to supply a provider-backed policy outside the
container. `docs/MigrationGuide.md` covers the `[Obsolete]` channel
virtuals and `DataLock`, and the non-re-entrant gate's contract for
channel subclasses. `docs/WhatsNewIn2.0.md` is updated.
`plans/cryptooffboard.md` is deleted now that the work it planned has
landed.

## Note for reviewers

This touches the secure channel handshake, which is the most
security-critical code in the stack. Nine distinct concurrency and
lifetime defects were found and fixed in it during this work — three
during development, two in review, four from CI — so `ChannelGate`, the
write path and the certificate ownership across the new suspension
points deserve the closest reading.

Five of those nine traced to the gate's `AsyncLocal`, which is why the
re-entrancy was subsequently removed and the `AsyncLocal` deleted. The
wrapper/`Core` split and the two documented residuals in that section
are the parts most worth a second reading.

The #4206 work removes the last reflection from `Security/Constants` and
rewrites the policy lookup tables, so
`SecurityConfiguration.SupportedSecurityPolicies` and the endpoint set
it feeds are worth a second look: an earlier revision of it changed that
set and broke six server tests, which is now covered by
`SecurityConfigurationBuildsExpectedSupportedPolicySet`.

## Related Issues

- Fixes #4206
- Fixes #4207
- Fixes #4208
- Fixes #4210
- Follow-up #4250 — this PR makes the security policy set injectable,
but nothing in the stack resolves `ISecurityPolicyRegistry` from DI yet,
so every production path still lands on the `Default` fallback. #4250
tracks threading it through `Session` and `UaSCBinaryChannel`, which is
what makes the injection points already added here load-bearing.

## Checklist

- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [x] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [x] I have addressed **all** PR feedback received.

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: marcschier <11168470+marcschier@users.noreply.github.com>
Copilot-Session: 7a68ca72-83e8-496c-b2f5-3df4c718320b
Copilot-Session: 3f5ab76a-c0ba-4f47-87ac-54d1f4182c6b
2026-08-15 05:23:20 -07:00
Marc Schier 4cbcec6e23 Update NuGet dependencies to latest and version ASP.NET Core per target framework (#4223)
# Description

Refreshes the centrally-managed NuGet dependencies in
`Directory.Packages.props` to their latest stable versions, and changes
how the ASP.NET Core packages are pinned so their version follows the
target framework.

## ASP.NET Core packages are now versioned per TFM

`Microsoft.AspNetCore.Authentication.Certificate`,
`Microsoft.AspNetCore.Authentication.JwtBearer`,
`Microsoft.AspNetCore.Mvc.Testing` and `Microsoft.AspNetCore.TestHost`
ship one band per .NET major, carry no `netstandard2.0` asset, and do
not roll forward across majors — a `net8.0` project simply cannot
consume the `10.0.x` band. A single central pin therefore had to sit on
the oldest supported band and hold *every* consumer there, which is why
these sat at `8.0.28` while `10.0.10` was current.

They are now selected from `$(TargetFramework)`, mirroring the existing
MQTTnet split:

| TFM | Version |
|---|---|
| `net8.0` | `8.0.29` |
| `net9.0` | `9.0.18` |
| everything else | `10.0.10` |

The last group is the fallback rather than an explicit `net10.0` match,
so a TFM the file does not enumerate — a future `net11.0`, or the
`net10.0` shell that legacy `netstandard2.0`/`netstandard2.1`
`$(CustomTestTarget)` builds fall back to — still resolves a version.
Verified against the generated `project.assets.json` that each TFM of
`Opc.Ua.Bindings.Https` really does resolve its own band.

## Version changes

`Crdt`/`Crdt.Transport` and the `RaftCs` family 1.1.2 · `Dekaf` 1.11.2 ·
`JsonSchema.Net` 9.4.0 · `Microsoft.Bcl.TimeProvider`, the
`Microsoft.Extensions.*` set and
`System.Composition.AttributedModel`/`System.Formats.Asn1`/`System.Text.Json`/`System.Threading.Channels`/`System.Threading.RateLimiting`
10.0.10 · `Microsoft.Extensions.Http.Resilience` and
`Microsoft.Extensions.TimeProvider.Testing` 10.8.0 ·
`Microsoft.NET.Test.Sdk` 18.8.1 · `Microsoft.SourceLink.*` 10.0.301 ·
`Nerdbank.GitVersioning` 3.10.91 · `Serilog` 4.4.0 ·
`System.CommandLine` 2.0.10 · `Avalonia`/`Avalonia.Desktop` 12.1.1 ·
`MQTTnet`/`MQTTnet.Server` 5.2.0.1603 (modern band only) ·
`Roslynator.*` 4.16.0 · `TUnit` 1.64.6.

The two `System.Collections.Immutable` `VersionOverride`s in the schema
test projects move to 10.0.10 to stay ahead of what `JsonSchema.Net`
requires.

## Removed: the DotNext pin

`DotNext` 5.26.3 was pinned centrally but no project references it. The
`docs/migrate/2.0.x/packages.md` row claiming `src/Opc.Ua.Lds.Server`
consumes it was also wrong — that project references only
`Makaretu.Dns.Multicast` and
`Microsoft.Extensions.Hosting.Abstractions`. Both are corrected.

## BouncyCastle held at 2.6.2 — CI caught a real regression

The first push of this branch took `BouncyCastle.Cryptography` to 2.7.0.
CI failed `Opc.Ua.Core.Tests` on **net48 only**
(`VerifyPEMSupportDirectoryStoreAsync` expecting 3 certificates and
getting 0), and the cause turned out to be a genuine behavioural break
rather than a flaky test.

BouncyCastle is referenced **only on net472/net48**, where it backs
`PEMReader`/`PEMWriter` in `Opc.Ua.Security.Certificates`. 2.7.0
tightened `Asn1.X509.TbsCertificateStructure` to throw:

```
certificate issuer is an empty distinguished name
```

`OpenSsl.PemReader.ReadObject()` therefore aborts on the *first* entry
of a chain whose issuer DN is empty. `ImportPublicKeysFromPEM` has no
per-object recovery, so the entire file is discarded and the store
enumerates nothing.

This is a **runtime** behaviour change, not a test artefact: .NET's own
PEM support on net8.0+ still accepts such a certificate, so taking 2.7.0
would let the same trusted-peer store load fine on net8.0+ and come back
**empty** on .NET Framework. Whether the stack *should* reject these
certificates on every TFM is a fair question, but it is a
security-behaviour decision that does not belong in a dependency refresh
— so the pin is documented in place with that context for a follow-up.

Confirmed by bisecting the package version against the net48 tests
(2.6.2 passes, 2.7.0 fails) and by reading the actual PEM asset with
both versions to capture the exact throw site.

## Deliberately left alone

Every existing pin with a documented reason is preserved, and each was
re-checked rather than assumed:

- **Roslyn compat band** (`roslyn.props`) — `Microsoft.CodeAnalysis.*`
stays on the pinned band and
`System.Collections.Immutable`/`System.Reflection.Metadata` stay on
`$(RoslynRuntimeVersion)`. Raising these is what re-breaks the analyzer
`ImmutableArray<T>` identity the file warns about, and it would raise
the minimum compiler that will load the shipped analyzers.
`Microsoft.CodeAnalysis.Analyzers` stays at 4.14.0 for the same reason.
- **`Microsoft.AspNetCore.*` 2.3.11** — last band with a
`netstandard2.0` asset; already latest.
- **`PacketDotNet` / `SharpPcap`** — SDL native-code pins; already
latest stable.
- **`System.Net.Http` 4.3.4 / `System.Text.RegularExpressions` 4.3.1 /
`System.Private.Uri` 4.3.2** — transitive CVE remediation pins; already
latest.
- **`MQTTnet` 4.3.7.1207** for `net472`/`net48`/`netstandard2.1` —
MQTTnet 5.x dropped those TFMs.
- **`BouncyCastle.Cryptography` 2.6.2** — see the section above.
- **`Moq`** — pinned.
- **Prerelease-only upgrades skipped** — `BenchmarkDotNet`
0.16.0-preview, `NUnit` 5.0.0-beta, `NUnit.Console` 4.0.0-beta,
`EmbedIO` 4.0.0-rc1, `Newtonsoft.Json` 13.0.5-beta, `PacketDotNet`
1.4.9-pre, and others.

## Overlap with #4195 — please note

**OpenUSD and ModelContextProtocol are intentionally not touched here.**
#4195 already moves OpenUSD to `0.6.0-alpha` together with the restored
render smoke job and the `OpenUsd.Rendering.Silk.Vulkan` package that
the bump actually depends on, and separately moves MCP to `2.1.0`.
Rev'ing either in this PR would duplicate that work, and would risk
silently downgrading MCP if the two landed in the wrong order. They are
left to #4195.

There is still a small expected overlap in `Directory.Packages.props`:
#4195 also bumps `Microsoft.Extensions.Configuration.Abstractions`,
`Microsoft.Extensions.Hosting.Abstractions` and `System.Text.Json` to
10.0.10 — the same values as here, so whichever merges second resolves
to an identical line.

## The one code change

Roslynator 4.16 adds **RCS1258**, which flags `TypeAttributes.Public |
TypeAttributes.Class` in `ComplexTypeBuilder`. It is correct:
`TypeAttributes.Class` is `0`, so the flag is a no-op, and the
`DefineEnum` call directly above already passes `TypeAttributes.Public`
alone. Dropping it is a verified semantic no-op (`Public | Class ==
Public`).

## Related Issues

_No tracking issue — routine dependency maintenance, in the same spirit
as the weekly Dependabot NuGet updates configured in
`.github/dependabot.yml`._

## Checklist

- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.<br/>_No new tests: this
changes dependency versions, not behaviour. The existing suite is the
proof, and the one code change is a verified no-op._
- [x] I have added all necessary
documentation.<br/>_`docs/migrate/2.0.x/packages.md` — corrected version
rows, removed the wrong `DotNext` row, added a section explaining the
per-TFM ASP.NET Core scheme._
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.<br/>_Full `UA.slnx` build across all six TFMs
(`net472`, `net48`, `netstandard2.1`, `net8.0`, `net9.0`, `net10.0`):
**0 warnings, 0 errors**. `dotnet restore`: 0 warnings. `dotnet pack`: 0
warnings, 0 errors, package validation passes._
- [x] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.<br/>_See
the verification note below._
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

### Update after the first CI run

The initial push failed one CI job — `Opc.Ua.Core.Tests` on net48, 2 PEM
tests. That was **not** flakiness: it was a real break from BouncyCastle
2.7.0, root-caused and fixed by holding that package at 2.6.2 (see the
section above). `Opc.Ua.Core.Tests` on net48 now runs **4161 passed / 0
failed** locally, and the full six-TFM build is still 0 warnings / 0
errors.

### Review feedback

Both review threads are addressed in `78bdd0ea3`:

- The **package table's third column was stale** in more rows than the
ones flagged. Every entry is now checked against the actual
`PackageReference` items — `System.Threading.Channels` belongs to
`Opc.Ua.Core`/`Core.Diagnostics`/`PubSub.Diagnostics` (not the LDS
server), the `Microsoft.CodeAnalysis.*` rows come from the
generator/analyzer variant targets under `tools/`, and
`Microsoft.CodeAnalysis.Analyzers` plus `System.Reflection.Metadata`
have no direct reference at all and are labelled as central pins. The
column is renamed **"Referenced by"**, which is what it actually records
and what makes it verifiable.
- The **BouncyCastle pin now references
[#4224](https://github.com/OPCFoundation/UA-.NETStandard/issues/4224)**,
which carries the decision on whether the stack should reject
empty-issuer certificates on every TFM, whether
`ImportPublicKeysFromPEM` should recover per entry, and whether the
expired `Test_chain.pem` asset should be regenerated.

## Verification note on the test run

The full net10.0 run covered ~48,000 tests. 15 failed, and each was
individually shown **not** to be caused by this change:

- **4 in `Opc.Ua.Core.Diagnostics.Tests`** (3×
`ReadChunkDecryptsStackEncryptedSymmetricChunk`,
`PrivateRequestSummaryFormatsKnownRequestKinds`) — reproduced
**identically at `HEAD` with the changes stashed**. Pre-existing.
- **8 across `Client`, `Di`, `WotCon.Samples`, `Server`** — all pass
when their project is run in isolation; they only fail under the
parallelism of a full-solution run. The machine also had ~45 orphaned
test processes holding sockets, which were cleared.
- **3 in `Gds`/`Stress`** — the log shows socket port exhaustion (`Only
one usage of each socket address...`). The `CertRotationLiveTests` pair
passes when run standalone, and that project's net10.0 package closure
contains **none** of the bumped packages (`BouncyCastle` is
`net472`/`net48`-only, so it cannot reach a net10.0 test at all).

The AOT/TUnit suite (`Opc.Ua.Aot.Tests`) was A/B tested: TUnit **1.58**
produced the same intermittent 0–2 failures as 1.64, confirming
pre-existing flakiness rather than a regression. On **1.64.6** it ran
**129/129 twice**.

`net48` was built and exercised via `CustomTestTarget=net48`; the
`MSB3277`/`NU1702` warnings it surfaces in `Opc.Ua.Stress.Tests` are
structural to that mode (the project builds `net8.0` while consuming
`net48` outputs) and pre-date this change — the `net462` asset's
assembly version simply tracks the patch number, so `10.0.0.9` became
`10.0.0.10`.

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: 2be367ab-e62d-4141-a4df-e5b2ca3cd126
2026-08-10 18:18:27 +00:00
Marc Schier f23b30e81a Own the certificates the TLS validation callbacks inspect (#4196)
Fixes the `test-ubuntu-latest-Sessions` failure that is currently red on
**master** ([run
31246003974](https://github.com/OPCFoundation/UA-.NETStandard/actions/runs/31246003974),
commit `5a6bbcce1`) and therefore on every pull request cut from it.

## The failure is not a failing test

`Opc.Ua.Sessions.Tests` passes — `Failed: 0, Passed: 777, Skipped: 379`.
The `dotnet test` step then exits **1** anyway, because the repository's
certificate-leak check runs after the suite and finds one outstanding
`Certificate` instance. The `BadUserAccessDenied` / *"Too many failed
authentication attempts"* noise in the log is a red herring: those
messages appear in the **passing macOS** run of the same suite too, and
are the expected product of tests that deliberately fail authentication.

## Cause

The TLS server-certificate validation callbacks built their OPC UA
`CertificateCollection` by wrapping the `X509ChainElement.Certificate`
instances the platform handed them. Those handles are **borrowed** — the
`X509Chain` owns them and frees them when it is disposed — so wrapping
them put two owners on one handle, and one certificate instance survived
to process exit.

It is timing-sensitive rather than deterministic, which is why macOS
passes and Linux does not, and why it presents as an intermittent leak
rather than a hard failure.

## Change

Each callback now copies the raw DER and builds the collection from
that, so the collection owns what it disposes and the chain keeps what
it owns:

- `src/Opc.Ua.Bindings.Https/Https/WebSocketByteTransport.cs`
- `src/Opc.Ua.Bindings.Https/Https/WssJsonTransportChannel.cs`
- `src/Opc.Ua.Client/WebApi/WebApiTransportChannel.cs`
- `src/Opc.Ua.Client/WebApi/WebApiWssTransportChannel.cs`
- `src/Opc.Ua.Core/Stack/Https/HttpsTransportChannel.cs`

**The validation decision is unchanged.** The same certificates are
inspected, in the same order, by the same logic — only their lifetime
differs. This is security-relevant code, so it is worth stating plainly
that nothing about what is accepted or rejected has moved.

`LeakDetectionHelpers` also gets its ceiling raised from 10s to 60s,
**keeping its quiescence semantics**: progress still resets the clock,
and a count that has stopped moving is still reported without waiting
for the cap. The settled window goes from 0.5s to 5s — long enough not
to race a loaded Linux agent's transport teardown, still prompt enough
to report a real leak quickly. An earlier attempt at this set the
settled window equal to the cap, which would have turned the check into
a flat 30-second sleep and destroyed its ability to tell a genuine leak
from a slow drain; that was rejected.

## Validation

`dotnet build UA.slnx` — 0 errors, 0 warnings.

| Suite | TFM | Passed | Failed | Exit |
|---|---|---:|---:|---:|
| `Opc.Ua.Sessions.Tests` | net10.0 | 776 | 0 | 0 |
| `Opc.Ua.Sessions.Tests` | net48 | 599 | 0 | 0 |
| `Opc.Ua.Bindings.Https.WebApi.Tests` | net10.0 | 337 | 0 | 0 |
| `Opc.Ua.Client.Tests` | net10.0 | 2123 | 0 | 0 |
| `Opc.Ua.Core.Tests` | net10.0 | 4153 | 0 | 0 |

7,988 passed, 0 failed. **Exit code 0** everywhere — which is the signal
that matters here, since the original bug was a suite that reported
all-pass and still exited 1. No `Certificate leak detected` message in
any run.

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: a248a589-9a20-4372-868e-5d347e57001b
2026-08-09 12:55:03 +02:00
Marc Schier 0612a43fe4 Pluggable cryptography and hardware-held private keys (#4192)
Makes the stack's cryptographic operations replaceable - by another library, an offboard service, or hardware (TPM 2.0 / HSM / PKCS#11 token / cloud KMS) - with no performance cost in the default configuration, and extends this to certificates so a private key need never exist in process memory.

Also fixes three pre-existing defects found while validating: STACKGEN001 erroring for every compilation the stack generator was merely loaded into, certificates failing to load from paths past MAX_PATH on Windows, and the MonitoredNode2 tests starving the thread pool.

Fixes #4190
2026-08-09 12:40:26 +02:00
Julius Pfrommer 2fb20c06a2 Use standardized OPC UA WebSocket transport profile URIs (#4133)
The WSS transport constants used the unregistered uawss- prefix for the
UA-SecureConversation/UA-Binary and UA-JSON profiles.

Use the profile URIs registered by the OPC Foundation:

https://profiles.opcfoundation.org/profile/254
https://profiles.opcfoundation.org/profile/253

The WebSocket mappings and sub-protocols are specified in OPC UA Part 6
section 7.5.2:

https://reference.opcfoundation.org/Core/Part6/v105/docs/7.5.2

Update the transport-profile helpers, regression tests, and
documentation accordingly so endpoint discovery publishes identifiers
recognized by conforming OPC UA clients and servers.

Tests: dotnet test tests/Opc.Ua.Core.Tests/Opc.Ua.Core.Tests.csproj -f
net10.0 --filter FullyQualifiedName~TransportProfileHelpersTests (39
passed)

# Description

_Describe the changes here to communicate to the maintainers why they
should accept this pull request. By default - this will become the
Commit message after merging and thus define history._

## Related Issues

_Reference all GitHub issues this PR addresses. If there is no issue
yet, open one and link it here._

_If this is a relatively large or complex change, a design must have
been discussed in the related tracking issue and signed off (which
becomes the Architectural Decision Record (ADR))._

- Fixes #github-issue-number, ...

## Checklist

_Put an `x` in the boxes that apply. You can complete these step by step
after opening the PR._

- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [ ] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [x] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

Co-authored-by: Julius Pfrommer <julius.pfrommer@o6-automation.com>
2026-07-31 09:39:11 +02:00
Marc Schier 8538f531e7 Update paths for the consolidated repository layout 2026-07-16 06:26:05 +02:00
Marc Schier 7cec2d614d Move repository files to the consolidated layout 2026-07-16 06:25:54 +02:00