Test | Fix Kerberos SSPI authentication failure when using TCP proxy in manual tests#4146
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ShreyaLaxminarayan wants to merge 1 commit intodotnet:mainfrom
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Test | Fix Kerberos SSPI authentication failure when using TCP proxy in manual tests#4146ShreyaLaxminarayan wants to merge 1 commit intodotnet:mainfrom
ShreyaLaxminarayan wants to merge 1 commit intodotnet:mainfrom
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…al tests Problem: CreateAndStartProxy used in manual tests rewrites the connection string address to 127.0.0.1, causing kerberos to construct the wrong SPN (MSSQLSvc/localhost) instead of the real server name. Since localhost is not registered in Active Directory, SSPI authentication fails with Microsoft.Data.SqlClient.SqlException: The target principal name is incorrect. Cannot generate SSPI context. Fix: Capture the original server name before the proxy rewrites the address. After rewriting, explicitly set ServerSPN in the connection string to the real server's SPN using DataTestUtility.GetMachineFQDN, but only if ServerSPN is not already set by the caller. Tests Affected: SqlCommandCancelTest.TimeOutDuringRead_Tcp— previously failing with SSPI error, now passing
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paulmedynski
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Codecov Report✅ All modified and coverable lines are covered by tests.
Additional details and impacted files@@ Coverage Diff @@
## main #4146 +/- ##
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- Coverage 73.22% 66.32% -6.91%
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Files 280 274 -6
Lines 43000 65782 +22782
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+ Hits 31486 43628 +12142
- Misses 11514 22154 +10640
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Problem:
CreateAndStartProxy used in manual tests rewrites the connection string address to 127.0.0.1, causing kerberos to construct the wrong SPN (MSSQLSvc/localhost) instead of the real server name. Since localhost is not registered in Active Directory, SSPI authentication fails with
Microsoft.Data.SqlClient.SqlException: The target principal name is incorrect. Cannot generate SSPI context.Kerberos builds the SPN from the resolved connection address. When the proxy rewrites the address to 127.0.0.1, the SPN is constructed from localhost instead of the actual server hostname, breaking AD lookup.
Fix:
Capture the original server name before the proxy rewrites the address. After rewriting, explicitly set ServerSPN in the connection string to the real server's SPN using DataTestUtility.GetMachineFQDN, but only if ServerSPN is not already set by the caller.
This fix only applies if ServerSPN is not set already.
Tests Affected:
SqlCommandCancelTest.TimeOutDuringRead_Tcp— previously failing with SSPI error, now passing