[✨ Triage] dotnet/runtime#120257 by rzikm - [Test Failure] HttpClientHandlerTest_Http3.Public_Interop_ExactVersion_B ...

[MihuBot]

Triage for dotnet/runtime#120257.
Repo filter: All networking issues.
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This is a test triage report generated by AI, aimed at helping the triage team quickly identify past issues/PRs that may be related.
Take any conclusions with a large grain of salt.

Tool logs

dotnet/runtime#120257: [Test Failure] HttpClientHandlerTest_Http3.Public_Interop_ExactVersion_BufferContent_Success(uri: "https://quic.nginx.org/") by rzikm
[Tool] Searching for HttpClientHandlerTest_Http3.Public_Interop_ExactVersion_BufferContent_Success, quic.nginx.org, Authentication failed because the remote party sent a TLS alert: '112', HttpClientHandlerTest_Http3, TLS alert 112 (IncludeOpen=True, IncludeClosed=True, IncludeIssues=True, IncludePullRequests=False, Repository=dotnet/runtime)
[Tool] Found 58 issues, 130 comments, 24 returned results (21745 ms)

Here are related issues and discussions for the test failure in issue #120257: "[Test Failure] HttpClientHandlerTest_Http3.Public_Interop_ExactVersion_BufferContent_Success(uri: "https://quic.nginx.org/")", which reports:

• Test failure in System.Net.Http.Functional.Tests.HttpClientHandlerTest_Http3.Public_Interop_ExactVersion_BufferContent_Success
• Error: Authentication failed because the remote party sent a TLS alert: '112'.

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Highly Relevant Issues

Issue #57498 (Aug 2021) - [HTTP/3] Test timeout: Public_Interop_ExactVersion_BufferContent_Success

• Discusses failures of the same test, but with a timeout error, against external servers (e.g., https://cloudflare-quic.com/).
• Comments highlight that failures against external servers are often not actionable and may be due to transient network/server issues.
• Suggestion: Exception should indicate it's an external server to help triage.
• Closed as not actionable after test endpoint stabilized.

Issue #63009 (Dec 2021) - [HTTP/3] test failure: Public_Interop_ExactVersion_BufferContent_Success fails with CONNECTION_IDLE

• Similar test, but with a different error (CONNECTION_IDLE) against another external endpoint.
• Comment: Issue attributed to remote endpoint problems; test was disabled for that endpoint.
• Endpoint was permanently removed from tests.

Issue #68692 (Apr 2022) - Test failure System.Net.Http.Functional.Tests.SocketsHttpHandlerTest_Http3_MsQuic.Public_Interop_ExactVersion_Success(uri: "https://www.litespeedtech.com/")

• Same test, different external endpoint, failed with HTTP status mismatch (Forbidden vs. OK).
• Comment: Probable cause is temporary unreachability or server-side change; not actionable.

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TLS Alert/Handshake Related Issues

Issue #98394 (Feb 2024) - [6.0] Failure in System.Net.Security.Tests.SyncSslStreamSystemDefaultTest.ClientAndServer_OneOrBothUseDefault_Ok due to remote TLS alert 'ProtocolVersion'

• Reports a TLS alert ('ProtocolVersion') from remote party during handshake.
• Comment: Rare, not easily actionable, likely external/environmental.

Issue #15856 (Dec 2015) - SslStream: Authentication failed because the remote party has closed the transport stream

• Reports similar error for SslStream; root cause was cipher suite mismatch between client/server.
• Discussion: Exception is not always helpful; underlying cause may be TLS negotiation/cipher mismatch.

Issue #17510 (Jun 2016) - System.Net.Security: Authentication failed because the remote party has closed the transport stream.

• Similar error in test; attributed to server closing connection during handshake.

Issue #31119 (Oct 2019) - TLS 1.2 The handshake failed due to an unexpected packet format

• TLS handshake failures, often due to network appliances/firewalls performing TLS inspection.
• Comment: Disabling inspection/firewall resolved issue.

Issue #77989 (Nov 2022) - TLS Handshake error: Win32Exception: The message received was unexpected or badly formatted

• TLS handshake error, resolved by increasing Windows registry TLS message size limit.
• Suggestion: Improve error messages/troubleshooting documentation.

Issue #18837 (Oct 2016, ongoing) - Supports TLS alerts for cert validation for non-Windows platforms

• Tracks work to improve TLS alert reporting and cert validation errors.
• Discussion: Improving error reporting for handshake failures is nontrivial, especially on non-Windows platforms.

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General QUIC/HTTP3 Test Flakiness

Issue #87552 (Jun 2023, updated 2024) - [Test Failure] System.Net.Http.Functional.Tests.HttpClientHandlerTest_Http3.ServerSendsTrailingHeaders_Success

• Reports flakiness in HTTP/3 tests, often attributed to external factors or reruns.

Issue #87814 (Jun 2023) - [Test Failure] System.Net.Http.Functional.Tests.HttpClientHandlerTest_Http3.ServerSendsTrailingHeaders_Success

• Duplicate of #87552.

Issue #74896 (Sep 2022) - Failures in SocketsHttpHandler_HttpClientHandler_MaxResponseHeadersLength_Http3 test

• HTTP/3 test failures, sometimes due to QUIC/HTTP3 issues or external endpoint problems.

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Summary and Guidance

• Most failures of this test are due to transient or permanent issues with external endpoints (e.g., quic.nginx.org).
• TLS alert '112' is sent by the remote server, typically indicating a handshake failure, which may be due to cipher suite mismatch, unsupported protocol, or server-side configuration.
• These issues are generally not actionable from the .NET side unless a pattern emerges or the endpoint is permanently misconfigured.
• Improving error reporting for TLS handshake failures is an ongoing area of work, but root causes are often external.
• If failures persist for a given endpoint, consider disabling or removing it from the test suite.

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Actionable Next Steps

• If this is a one-off or rare failure, it can be considered not actionable.
• If failures against quic.nginx.org become frequent, consider removing or disabling tests for this endpoint, as was done for other endpoints in previous issues.
• If you need to improve error reporting, see ongoing work in #18837 and #77989.

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References:

• Issue #57498
• Issue #63009
• Issue #68692
• Issue #98394
• Issue #15856
• Issue #18837
• Issue #77989
• Issue #87552
• Issue #74896

Let me know if you need a deeper dive into any specific issue or discussion!