# 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>
OPC Foundation UA .NET Standard Reference Server
Introduction
The console reference server can be configured using several console parameters. Some of these parameters are explained in more detail below.
To see all available parameters call console reference server with the parameter -h.
Historical Access
The reference server starts with an in-memory Part 11 historian. Its historized
scalar nodes expose raw, modified, at-time, aggregate, annotation, and update
operations together with populated HistoricalDataConfigurationType
companions. CTT/Historical_KeyValuePairs demonstrates generic
StructuredHistoryData with two KeyValuePair entries at one timestamp. The
CTT notifier exposes historical event read/write bits, a
HistoricalEventConfigurationType companion, and seeded event history.
Writes to the two event-trigger variables report events; live forwarding
completes before the historian snapshots them into its bounded asynchronous
capture queue.
Run the matching client workflow with:
dotnet ConsoleReferenceClient.dll --historian --autoaccept --nosecurity \
opc.tcp://localhost:62541/Quickstarts/ReferenceServer
See docs/HistoricalAccess.md for the
provider contracts, status semantics, and custom storage examples.
Reverse Connect
The OPC UA reverse connect feature allows an OPC UA server to initiate the connection to a client, rather than the traditional model where clients connect to servers. This is particularly useful in scenarios where the server is behind a firewall or NAT, making it difficult for clients to directly connect to it.
How to use Reverse Connect
To enable reverse connect mode, specify the client endpoint URL using the --rc or --reverseconnect parameter:
dotnet ConsoleReferenceServer.dll --rc=opc.tcp://localhost:65300
or
dotnet ConsoleReferenceServer.dll --reverseconnect=opc.tcp://localhost:65300
Example: Server and Client with Reverse Connect
-
Start the client with reverse connect listener on port 65300:
dotnet ConsoleReferenceClient.dll --rc=opc.tcp://localhost:65300 opc.tcp://localhost:62541/Quickstarts/ReferenceServer -
In a separate terminal, start the server with reverse connect to the client:
dotnet ConsoleReferenceServer.dll --rc=opc.tcp://localhost:65300 -a
The server will establish a reverse connection to the client endpoint, and the client will use this connection to communicate with the server.
Additional Options
-aor--autoaccept: Auto accept untrusted certificates (for testing only)-cor--console: Log to console-lor--log: Log app output-tor--timeout: Timeout in seconds to exit application
For the complete list of options, use --help.
X509 user identity certificates
The reference server validates X509 user identity tokens against its trusted-user certificate
store (TrustedUserCertificates, by default %LocalApplicationData%/OPC Foundation/pki/trustedUser).
An untrusted user certificate is rejected with BadIdentityTokenRejected — the --autoaccept option
only auto-accepts the application/channel certificate, never user identity certificates.
To let a trusted client (for example the OPC Foundation Compliance Test Tool) authenticate with an
X509 user token, its user certificate must be present in that store. To make provisioning easy, the
server writes every rejected X509 user certificate to a dedicated review store,
pki/rejectedUser (a sibling of pki/trustedUser). After one failing activation you can move the
legitimate user certificate from pki/rejectedUser/certs into pki/trustedUser/certs (and any
issuing CA into pki/issuerUser/certs) and reconnect. Deliberately-untrusted certificates simply stay
out of the trusted store and continue to be rejected.