Add delegate flag to fix permissions when querying linked SQL Servers (#26270)

Author: ah-

src/Common/src/System/Net/ContextFlagsAdapterPal.Unix.cs

@@ -26,7 +26,8 @@ public ContextFlagMapping(Interop.NetSecurityNative.GssFlags gssFlag, ContextFla
             new ContextFlagMapping(Interop.NetSecurityNative.GssFlags.GSS_C_IDENTIFY_FLAG, ContextFlagsPal.InitIdentify),
             new ContextFlagMapping(Interop.NetSecurityNative.GssFlags.GSS_C_MUTUAL_FLAG, ContextFlagsPal.MutualAuth),
             new ContextFlagMapping(Interop.NetSecurityNative.GssFlags.GSS_C_REPLAY_FLAG, ContextFlagsPal.ReplayDetect),
-            new ContextFlagMapping(Interop.NetSecurityNative.GssFlags.GSS_C_SEQUENCE_FLAG, ContextFlagsPal.SequenceDetect)
+            new ContextFlagMapping(Interop.NetSecurityNative.GssFlags.GSS_C_SEQUENCE_FLAG, ContextFlagsPal.SequenceDetect),
+            new ContextFlagMapping(Interop.NetSecurityNative.GssFlags.GSS_C_DELEG_FLAG, ContextFlagsPal.Delegate)
         };
 
 

src/System.Data.SqlClient/src/System/Data/SqlClient/SNI/SNIProxy.cs

@@ -105,6 +105,7 @@ public void GenSspiClientContext(SspiClientContextStatus sspiClientContextStatus
 
             ContextFlagsPal requestedContextFlags = ContextFlagsPal.Connection
                 | ContextFlagsPal.Confidentiality
+                | ContextFlagsPal.Delegate
                 | ContextFlagsPal.MutualAuth;
 
             string serverSPN = System.Text.Encoding.UTF8.GetString(serverName);