internal static int Encrypt(
            SafeDeleteContext securityContext,
            byte[] buffer,
            int offset,
            int count,
            bool isConfidential,
            bool isNtlm,
            ref byte[] output,
            uint sequenceNumber)
        {
            Debug.Assert(!isNtlm, "Encrypt: NTLM is not yet supported");
            SafeDeleteNegoContext gssContext = (SafeDeleteNegoContext)securityContext;

            byte[] tempOutput = Interop.GssApi.Encrypt(gssContext.GssContext, isConfidential, buffer, offset, count);

            // Create space for prefixing with the length
            const int prefixLength = 4;

            output = new byte[tempOutput.Length + prefixLength];
            Array.Copy(tempOutput, 0, output, prefixLength, tempOutput.Length);
            int resultSize = tempOutput.Length;

            unchecked
            {
                output[0] = (byte)((resultSize) & 0xFF);
                output[1] = (byte)(((resultSize) >> 8) & 0xFF);
                output[2] = (byte)(((resultSize) >> 16) & 0xFF);
                output[3] = (byte)(((resultSize) >> 24) & 0xFF);
            }

            return(resultSize + 4);
        }
Example #2
0
        internal static int Encrypt(
            SafeDeleteContext securityContext,
            ReadOnlySpan <byte> buffer,
            bool isConfidential,
            bool isNtlm,
            [NotNull] ref byte[]?output,
            uint sequenceNumber)
        {
            SafeDeleteNegoContext gssContext = (SafeDeleteNegoContext)securityContext;

            byte[] tempOutput = GssWrap(gssContext.GssContext, isConfidential, buffer);

            // Create space for prefixing with the length
            const int prefixLength = 4;

            output = new byte[tempOutput.Length + prefixLength];
            Array.Copy(tempOutput, 0, output, prefixLength, tempOutput.Length);
            int resultSize = tempOutput.Length;

            unchecked
            {
                output[0] = (byte)((resultSize) & 0xFF);
                output[1] = (byte)(((resultSize) >> 8) & 0xFF);
                output[2] = (byte)(((resultSize) >> 16) & 0xFF);
                output[3] = (byte)(((resultSize) >> 24) & 0xFF);
            }

            return(resultSize + 4);
        }
Example #3
0
        internal static int MakeSignature(SafeDeleteContext securityContext, byte[] buffer, int offset, int count, [AllowNull] ref byte[] output)
        {
            SafeDeleteNegoContext gssContext = (SafeDeleteNegoContext)securityContext;

            output = GssWrap(gssContext.GssContext, false, new ReadOnlySpan <byte>(buffer, offset, count));
            return(output.Length);
        }
        internal static SecurityStatusPal AcceptSecurityContext(
            SafeFreeCredentials credentialsHandle,
            ref SafeDeleteContext securityContext,
            ContextFlagsPal requestedContextFlags,
            byte[] incomingBlob,
            ChannelBinding channelBinding,
            ref byte[] resultBlob,
            ref ContextFlagsPal contextFlags)
        {
            if (securityContext == null)
            {
                securityContext = new SafeDeleteNegoContext((SafeFreeNegoCredentials)credentialsHandle);
            }

            SafeDeleteNegoContext negoContext = (SafeDeleteNegoContext)securityContext;

            try
            {
                SafeGssContextHandle contextHandle = negoContext.GssContext;
                bool done = GssAcceptSecurityContext(
                    ref contextHandle,
                    incomingBlob,
                    out resultBlob,
                    out uint outputFlags);

                Debug.Assert(resultBlob != null, "Unexpected null buffer returned by GssApi");
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);

                // Save the inner context handle for further calls to NetSecurity
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);
                if (null == negoContext.GssContext)
                {
                    negoContext.SetGssContext(contextHandle);
                }

                contextFlags = ContextFlagsAdapterPal.GetContextFlagsPalFromInterop(
                    (Interop.NetSecurityNative.GssFlags)outputFlags, isServer: true);

                SecurityStatusPalErrorCode errorCode = done ?
                                                       (negoContext.IsNtlmUsed && resultBlob.Length > 0 ? SecurityStatusPalErrorCode.OK : SecurityStatusPalErrorCode.CompleteNeeded) :
                                                       SecurityStatusPalErrorCode.ContinueNeeded;

                return(new SecurityStatusPal(errorCode));
            }
            catch (Exception ex)
            {
                if (NetEventSource.IsEnabled)
                {
                    NetEventSource.Error(null, ex);
                }
                return(new SecurityStatusPal(SecurityStatusPalErrorCode.InternalError, ex));
            }
        }
Example #5
0
        private static string GetUser(
            ref SafeDeleteContext securityContext)
        {
            SafeDeleteNegoContext negoContext = (SafeDeleteNegoContext)securityContext;

            try
            {
                SafeGssContextHandle?contextHandle = negoContext.GssContext;
                return(GssGetUser(ref contextHandle));
            }
            catch (Exception ex)
            {
                if (NetEventSource.Log.IsEnabled())
                {
                    NetEventSource.Error(null, ex);
                }
                throw;
            }
        }
Example #6
0
        internal static int MakeSignature(SafeDeleteContext securityContext, byte[] buffer, int offset, int count, [AllowNull] ref byte[] output)
        {
            SafeDeleteNegoContext gssContext = (SafeDeleteNegoContext)securityContext;

            byte[] tempOutput = GssWrap(gssContext.GssContext, false, new ReadOnlySpan <byte>(buffer, offset, count));
            // Create space for prefixing with the length
            const int prefixLength = 4;

            output = new byte[tempOutput.Length + prefixLength];
            Array.Copy(tempOutput, 0, output, prefixLength, tempOutput.Length);
            int resultSize = tempOutput.Length;

            unchecked
            {
                output[0] = (byte)((resultSize) & 0xFF);
                output[1] = (byte)(((resultSize) >> 8) & 0xFF);
                output[2] = (byte)(((resultSize) >> 16) & 0xFF);
                output[3] = (byte)(((resultSize) >> 24) & 0xFF);
            }

            return(resultSize + 4);
        }
Example #7
0
        internal static SecurityStatusPal AcceptSecurityContext(
            SafeFreeCredentials?credentialsHandle,
            ref SafeDeleteContext?securityContext,
            ContextFlagsPal requestedContextFlags,
            byte[]?incomingBlob,
            ChannelBinding?channelBinding,
            ref byte[] resultBlob,
            ref ContextFlagsPal contextFlags)
        {
            if (securityContext == null)
            {
                securityContext = new SafeDeleteNegoContext((SafeFreeNegoCredentials)credentialsHandle !);
            }

            SafeDeleteNegoContext negoContext = (SafeDeleteNegoContext)securityContext;

            try
            {
                SafeGssContextHandle?contextHandle = negoContext.GssContext;
                bool done = GssAcceptSecurityContext(
                    ref contextHandle,
                    negoContext.AcceptorCredential,
                    incomingBlob,
                    out resultBlob,
                    out uint outputFlags,
                    out bool isNtlmUsed);

                Debug.Assert(resultBlob != null, "Unexpected null buffer returned by GssApi");
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);

                // Save the inner context handle for further calls to NetSecurity
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);
                if (null == negoContext.GssContext)
                {
                    negoContext.SetGssContext(contextHandle !);
                }

                contextFlags = ContextFlagsAdapterPal.GetContextFlagsPalFromInterop(
                    (Interop.NetSecurityNative.GssFlags)outputFlags, isServer: true);

                SecurityStatusPalErrorCode errorCode;
                if (done)
                {
                    if (NetEventSource.Log.IsEnabled())
                    {
                        string protocol = isNtlmUsed ? "SPNEGO-NTLM" : "SPNEGO-Kerberos";
                        NetEventSource.Info(securityContext, $"AcceptSecurityContext: actual protocol = {protocol}");
                    }

                    negoContext.SetAuthenticationPackage(isNtlmUsed);
                    errorCode = (isNtlmUsed && resultBlob.Length > 0) ? SecurityStatusPalErrorCode.OK : SecurityStatusPalErrorCode.CompleteNeeded;
                }
                else
                {
                    errorCode = SecurityStatusPalErrorCode.ContinueNeeded;
                }

                return(new SecurityStatusPal(errorCode));
            }
            catch (Interop.NetSecurityNative.GssApiException gex)
            {
                if (NetEventSource.Log.IsEnabled())
                {
                    NetEventSource.Error(null, gex);
                }
                return(new SecurityStatusPal(GetErrorCode(gex), gex));
            }
            catch (Exception ex)
            {
                if (NetEventSource.Log.IsEnabled())
                {
                    NetEventSource.Error(null, ex);
                }
                return(new SecurityStatusPal(SecurityStatusPalErrorCode.InternalError, ex));
            }
        }
Example #8
0
        internal static string QueryContextAuthenticationPackage(SafeDeleteContext securityContext)
        {
            SafeDeleteNegoContext negoContext = (SafeDeleteNegoContext)securityContext;

            return(negoContext.IsNtlmUsed ? NegotiationInfoClass.NTLM : NegotiationInfoClass.Kerberos);
        }
Example #9
0
        private static SecurityStatusPal EstablishSecurityContext(
            SafeFreeNegoCredentials credential,
            ref SafeDeleteContext?context,
            ChannelBinding?channelBinding,
            string?targetName,
            ContextFlagsPal inFlags,
            byte[]?incomingBlob,
            ref byte[]?resultBuffer,
            ref ContextFlagsPal outFlags)
        {
            bool isNtlmOnly = credential.IsNtlmOnly;

            if (context == null)
            {
                if (NetEventSource.Log.IsEnabled())
                {
                    string protocol = isNtlmOnly ? "NTLM" : "SPNEGO";
                    NetEventSource.Info(context, $"requested protocol = {protocol}, target = {targetName}");
                }

                context = new SafeDeleteNegoContext(credential, targetName !);
            }

            SafeDeleteNegoContext negoContext = (SafeDeleteNegoContext)context;

            try
            {
                Interop.NetSecurityNative.GssFlags inputFlags =
                    ContextFlagsAdapterPal.GetInteropFromContextFlagsPal(inFlags, isServer: false);
                uint outputFlags;
                bool isNtlmUsed;
                SafeGssContextHandle?contextHandle = negoContext.GssContext;
                bool done = GssInitSecurityContext(
                    ref contextHandle,
                    credential.GssCredential,
                    isNtlmOnly,
                    channelBinding,
                    negoContext.TargetName,
                    inputFlags,
                    incomingBlob,
                    out resultBuffer,
                    out outputFlags,
                    out isNtlmUsed);

                if (done)
                {
                    if (NetEventSource.Log.IsEnabled())
                    {
                        string protocol = isNtlmOnly ? "NTLM" : isNtlmUsed ? "SPNEGO-NTLM" : "SPNEGO-Kerberos";
                        NetEventSource.Info(context, $"actual protocol = {protocol}");
                    }

                    // Populate protocol used for authentication
                    negoContext.SetAuthenticationPackage(isNtlmUsed);
                }

                Debug.Assert(resultBuffer != null, "Unexpected null buffer returned by GssApi");
                outFlags = ContextFlagsAdapterPal.GetContextFlagsPalFromInterop(
                    (Interop.NetSecurityNative.GssFlags)outputFlags, isServer: false);
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);

                // Save the inner context handle for further calls to NetSecurity
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);
                if (null == negoContext.GssContext)
                {
                    negoContext.SetGssContext(contextHandle !);
                }

                SecurityStatusPalErrorCode errorCode = done ?
                                                       (negoContext.IsNtlmUsed && resultBuffer.Length > 0 ? SecurityStatusPalErrorCode.OK : SecurityStatusPalErrorCode.CompleteNeeded) :
                                                       SecurityStatusPalErrorCode.ContinueNeeded;
                return(new SecurityStatusPal(errorCode));
            }
            catch (Exception ex)
            {
                if (NetEventSource.Log.IsEnabled())
                {
                    NetEventSource.Error(null, ex);
                }
                return(new SecurityStatusPal(SecurityStatusPalErrorCode.InternalError, ex));
            }
        }
Example #10
0
        private static SecurityStatusPal EstablishSecurityContext(
            SafeFreeNegoCredentials credential,
            ref SafeDeleteContext context,
            string targetName,
            ContextFlagsPal inFlags,
            SecurityBuffer inputBuffer,
            SecurityBuffer outputBuffer,
            ref ContextFlagsPal outFlags)
        {
            bool isNtlmOnly = credential.IsNtlmOnly;

            if (context == null)
            {
                // Empty target name causes the failure on Linux, hence passing a non-empty string
                context = isNtlmOnly ? new SafeDeleteNegoContext(credential, credential.UserName) : new SafeDeleteNegoContext(credential, targetName);
            }

            SafeDeleteNegoContext negoContext = (SafeDeleteNegoContext)context;

            try
            {
                Interop.NetSecurityNative.GssFlags inputFlags = ContextFlagsAdapterPal.GetInteropFromContextFlagsPal(inFlags, isServer: false);
                uint outputFlags;
                int  isNtlmUsed;
                SafeGssContextHandle contextHandle = negoContext.GssContext;
                bool done = GssInitSecurityContext(
                    ref contextHandle,
                    credential.GssCredential,
                    isNtlmOnly,
                    negoContext.TargetName,
                    inputFlags,
                    inputBuffer?.token,
                    out outputBuffer.token,
                    out outputFlags,
                    out isNtlmUsed);

                Debug.Assert(outputBuffer.token != null, "Unexpected null buffer returned by GssApi");
                outputBuffer.size   = outputBuffer.token.Length;
                outputBuffer.offset = 0;
                outFlags            = ContextFlagsAdapterPal.GetContextFlagsPalFromInterop((Interop.NetSecurityNative.GssFlags)outputFlags, isServer: false);
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);

                // Save the inner context handle for further calls to NetSecurity
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);
                if (null == negoContext.GssContext)
                {
                    negoContext.SetGssContext(contextHandle);
                }

                // Populate protocol used for authentication
                if (done)
                {
                    negoContext.SetAuthenticationPackage(Convert.ToBoolean(isNtlmUsed));
                }

                SecurityStatusPalErrorCode errorCode = done ?
                                                       (negoContext.IsNtlmUsed && outputBuffer.size > 0 ? SecurityStatusPalErrorCode.OK : SecurityStatusPalErrorCode.CompleteNeeded) :
                                                       SecurityStatusPalErrorCode.ContinueNeeded;
                return(new SecurityStatusPal(errorCode));
            }
            catch (Exception ex)
            {
                if (NetEventSource.IsEnabled)
                {
                    NetEventSource.Error(null, ex);
                }
                return(new SecurityStatusPal(SecurityStatusPalErrorCode.InternalError, ex));
            }
        }
Example #11
0
        internal static SecurityStatusPal AcceptSecurityContext(
            SafeFreeCredentials?credentialsHandle,
            ref SafeDeleteContext?securityContext,
            ContextFlagsPal requestedContextFlags,
            ReadOnlySpan <byte> incomingBlob,
            ChannelBinding?channelBinding,
            ref byte[] resultBlob,
            out int resultBlobLength,
            ref ContextFlagsPal contextFlags)
        {
            securityContext ??= new SafeDeleteNegoContext((SafeFreeNegoCredentials)credentialsHandle !);

            SafeDeleteNegoContext negoContext   = (SafeDeleteNegoContext)securityContext;
            SafeGssContextHandle  contextHandle = negoContext.GssContext;

            Interop.NetSecurityNative.GssBuffer token = default(Interop.NetSecurityNative.GssBuffer);
            try
            {
                Interop.NetSecurityNative.Status status;
                Interop.NetSecurityNative.Status minorStatus;
                status = Interop.NetSecurityNative.AcceptSecContext(out minorStatus,
                                                                    negoContext.AcceptorCredential,
                                                                    ref contextHandle,
                                                                    incomingBlob,
                                                                    ref token,
                                                                    out uint outputFlags,
                                                                    out bool isNtlmUsed);

                if ((status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE) &&
                    (status != Interop.NetSecurityNative.Status.GSS_S_CONTINUE_NEEDED))
                {
                    if (negoContext.GssContext.IsInvalid)
                    {
                        contextHandle.Dispose();
                    }

                    Interop.NetSecurityNative.GssApiException gex = new Interop.NetSecurityNative.GssApiException(status, minorStatus);
                    if (NetEventSource.Log.IsEnabled())
                    {
                        NetEventSource.Error(null, gex);
                    }
                    resultBlobLength = 0;
                    return(new SecurityStatusPal(GetErrorCode(gex), gex));
                }

                resultBlob = token.ToByteArray();

                Debug.Assert(resultBlob != null, "Unexpected null buffer returned by GssApi");

                contextFlags = ContextFlagsAdapterPal.GetContextFlagsPalFromInterop(
                    (Interop.NetSecurityNative.GssFlags)outputFlags, isServer: true);
                resultBlobLength = resultBlob.Length;

                SecurityStatusPalErrorCode errorCode;
                if (status == Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
                {
                    if (NetEventSource.Log.IsEnabled())
                    {
                        string protocol = isNtlmUsed ? "SPNEGO-NTLM" : "SPNEGO-Kerberos";
                        NetEventSource.Info(securityContext, $"AcceptSecurityContext: actual protocol = {protocol}");
                    }

                    negoContext.SetAuthenticationPackage(isNtlmUsed);
                    errorCode = SecurityStatusPalErrorCode.OK;
                }
                else
                {
                    errorCode = SecurityStatusPalErrorCode.ContinueNeeded;
                }

                return(new SecurityStatusPal(errorCode));
            }
            catch (Exception ex)
            {
                if (NetEventSource.Log.IsEnabled())
                {
                    NetEventSource.Error(null, ex);
                }
                resultBlobLength = 0;
                return(new SecurityStatusPal(SecurityStatusPalErrorCode.InternalError, ex));
            }
            finally
            {
                token.Dispose();

                // Save the inner context handle for further calls to NetSecurity
                //
                // For the first call `negoContext.GssContext` is invalid and we expect the
                // inital handle to be returned from AcceptSecContext. For any subsequent
                // call the handle should stay the same or it can be destroyed by the native
                // AcceptSecContext call.
                Debug.Assert(
                    negoContext.GssContext == contextHandle ||
                    negoContext.GssContext.IsInvalid ||
                    contextHandle.IsInvalid);
                negoContext.SetGssContext(contextHandle);
            }
        }
Example #12
0
        private static SecurityStatusPal EstablishSecurityContext(
            SafeFreeNegoCredentials credential,
            ref SafeDeleteContext?context,
            ChannelBinding?channelBinding,
            string?targetName,
            ContextFlagsPal inFlags,
            ReadOnlySpan <byte> incomingBlob,
            out byte[]?resultBuffer,
            ref ContextFlagsPal outFlags)
        {
            bool isNtlmOnly = credential.IsNtlmOnly;

            resultBuffer = null;

            if (context == null)
            {
                if (NetEventSource.Log.IsEnabled())
                {
                    string protocol = isNtlmOnly ? "NTLM" : "SPNEGO";
                    NetEventSource.Info(context, $"requested protocol = {protocol}, target = {targetName}");
                }

                context = new SafeDeleteNegoContext(credential, targetName !);
            }

            Interop.NetSecurityNative.GssBuffer token = default(Interop.NetSecurityNative.GssBuffer);
            Interop.NetSecurityNative.Status    status;
            Interop.NetSecurityNative.Status    minorStatus;
            SafeDeleteNegoContext negoContext   = (SafeDeleteNegoContext)context;
            SafeGssContextHandle  contextHandle = negoContext.GssContext;

            try
            {
                Interop.NetSecurityNative.GssFlags inputFlags =
                    ContextFlagsAdapterPal.GetInteropFromContextFlagsPal(inFlags, isServer: false);
                uint outputFlags;
                bool isNtlmUsed;

                if (channelBinding != null)
                {
                    // If a TLS channel binding token (cbt) is available then get the pointer
                    // to the application specific data.
                    int appDataOffset = Marshal.SizeOf <SecChannelBindings>();
                    Debug.Assert(appDataOffset < channelBinding.Size);
                    IntPtr cbtAppData     = channelBinding.DangerousGetHandle() + appDataOffset;
                    int    cbtAppDataSize = channelBinding.Size - appDataOffset;
                    status = Interop.NetSecurityNative.InitSecContext(out minorStatus,
                                                                      credential.GssCredential,
                                                                      ref contextHandle,
                                                                      isNtlmOnly,
                                                                      cbtAppData,
                                                                      cbtAppDataSize,
                                                                      negoContext.TargetName,
                                                                      (uint)inputFlags,
                                                                      incomingBlob,
                                                                      ref token,
                                                                      out outputFlags,
                                                                      out isNtlmUsed);
                }
                else
                {
                    status = Interop.NetSecurityNative.InitSecContext(out minorStatus,
                                                                      credential.GssCredential,
                                                                      ref contextHandle,
                                                                      isNtlmOnly,
                                                                      negoContext.TargetName,
                                                                      (uint)inputFlags,
                                                                      incomingBlob,
                                                                      ref token,
                                                                      out outputFlags,
                                                                      out isNtlmUsed);
                }

                if ((status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE) &&
                    (status != Interop.NetSecurityNative.Status.GSS_S_CONTINUE_NEEDED))
                {
                    if (negoContext.GssContext.IsInvalid)
                    {
                        context.Dispose();
                    }

                    Interop.NetSecurityNative.GssApiException gex = new Interop.NetSecurityNative.GssApiException(status, minorStatus);
                    if (NetEventSource.Log.IsEnabled())
                    {
                        NetEventSource.Error(null, gex);
                    }
                    resultBuffer = Array.Empty <byte>();
                    return(new SecurityStatusPal(GetErrorCode(gex), gex));
                }

                resultBuffer = token.ToByteArray();

                if (status == Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
                {
                    if (NetEventSource.Log.IsEnabled())
                    {
                        string protocol = isNtlmOnly ? "NTLM" : isNtlmUsed ? "SPNEGO-NTLM" : "SPNEGO-Kerberos";
                        NetEventSource.Info(context, $"actual protocol = {protocol}");
                    }

                    // Populate protocol used for authentication
                    negoContext.SetAuthenticationPackage(isNtlmUsed);
                }

                Debug.Assert(resultBuffer != null, "Unexpected null buffer returned by GssApi");
                outFlags = ContextFlagsAdapterPal.GetContextFlagsPalFromInterop(
                    (Interop.NetSecurityNative.GssFlags)outputFlags, isServer: false);

                SecurityStatusPalErrorCode errorCode = status == Interop.NetSecurityNative.Status.GSS_S_COMPLETE ?
                                                       SecurityStatusPalErrorCode.OK :
                                                       SecurityStatusPalErrorCode.ContinueNeeded;
                return(new SecurityStatusPal(errorCode));
            }
            catch (Exception ex)
            {
                if (NetEventSource.Log.IsEnabled())
                {
                    NetEventSource.Error(null, ex);
                }
                return(new SecurityStatusPal(SecurityStatusPalErrorCode.InternalError, ex));
            }
            finally
            {
                token.Dispose();

                // Save the inner context handle for further calls to NetSecurity
                //
                // For the first call `negoContext.GssContext` is invalid and we expect the
                // inital handle to be returned from InitSecContext. For any subsequent
                // call the handle should stay the same or it can be destroyed by the native
                // InitSecContext call.
                Debug.Assert(
                    negoContext.GssContext == contextHandle ||
                    negoContext.GssContext.IsInvalid ||
                    contextHandle.IsInvalid);
                negoContext.SetGssContext(contextHandle);
            }
        }
        private static SecurityStatusPal EstablishSecurityContext(
            SafeFreeNegoCredentials credential,
            ref SafeDeleteContext context,
            bool isNtlm,
            string targetName,
            ContextFlagsPal inFlags,
            SecurityBuffer inputBuffer,
            SecurityBuffer outputBuffer,
            ref ContextFlagsPal outFlags)
        {
            Debug.Assert(!isNtlm, "EstablishSecurityContext: NTLM is not yet supported");

            if (context == null)
            {
                context = new SafeDeleteNegoContext(credential, targetName);
            }

            SafeDeleteNegoContext negoContext = (SafeDeleteNegoContext)context;

            try
            {
                Interop.NetSecurityNative.GssFlags inputFlags = ContextFlagsAdapterPal.GetInteropFromContextFlagsPal(inFlags);
                uint outputFlags;
                SafeGssContextHandle contextHandle = negoContext.GssContext;
                bool done = Interop.GssApi.EstablishSecurityContext(
                    ref contextHandle,
                    credential.GssCredential,
                    isNtlm,
                    negoContext.TargetName,
                    inputFlags,
                    inputBuffer?.token,
                    out outputBuffer.token,
                    out outputFlags);

                Debug.Assert(outputBuffer.token != null, "Unexpected null buffer returned by GssApi");
                outputBuffer.size   = outputBuffer.token.Length;
                outputBuffer.offset = 0;

                outFlags = ContextFlagsAdapterPal.GetContextFlagsPalFromInterop((Interop.NetSecurityNative.GssFlags)outputFlags);

                // Save the inner context handle for further calls to NetSecurity
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);
                if (null == negoContext.GssContext)
                {
                    negoContext.SetGssContext(contextHandle);
                }

                SecurityStatusPalErrorCode errorCode = done ? SecurityStatusPalErrorCode.CompleteNeeded : SecurityStatusPalErrorCode.ContinueNeeded;
                return(new SecurityStatusPal(errorCode));
            }
            catch (Exception ex)
            {
                //TODO (Issue #5890): Print exception until issue is fixed
                Debug.Write("Exception Caught. - " + ex);
                if (GlobalLog.IsEnabled)
                {
                    GlobalLog.Print("Exception Caught. - " + ex);
                }

                return(new SecurityStatusPal(SecurityStatusPalErrorCode.InternalError, ex));
            }
        }
        private static SecurityStatusPal EstablishSecurityContext(
          SafeFreeNegoCredentials credential,
          ref SafeDeleteContext context,
          bool isNtlm,
          string targetName,
          ContextFlagsPal inFlags,
          SecurityBuffer inputBuffer,
          SecurityBuffer outputBuffer,
          ref ContextFlagsPal outFlags)
        {
            Debug.Assert(!isNtlm, "EstablishSecurityContext: NTLM is not yet supported");

            if (context == null)
            {
                context = new SafeDeleteNegoContext(credential, targetName);
            }

            SafeDeleteNegoContext negoContext = (SafeDeleteNegoContext)context;
            try
            {
                Interop.NetSecurityNative.GssFlags inputFlags = ContextFlagsAdapterPal.GetInteropFromContextFlagsPal(inFlags);
                uint outputFlags;
                SafeGssContextHandle contextHandle = negoContext.GssContext;
                bool done = Interop.GssApi.EstablishSecurityContext(
                   ref contextHandle,
                   credential.GssCredential,
                   isNtlm,
                   negoContext.TargetName,
                   inputFlags,
                   inputBuffer?.token,
                   out outputBuffer.token,
                   out outputFlags);

                Debug.Assert(outputBuffer.token != null, "Unexpected null buffer returned by GssApi");
                outputBuffer.size = outputBuffer.token.Length;
                outputBuffer.offset = 0;

                outFlags = ContextFlagsAdapterPal.GetContextFlagsPalFromInterop((Interop.NetSecurityNative.GssFlags)outputFlags);

                // Save the inner context handle for further calls to NetSecurity
                Debug.Assert(negoContext.GssContext == null || contextHandle == negoContext.GssContext);
                if (null == negoContext.GssContext)
                {
                    negoContext.SetGssContext(contextHandle);
                }

                SecurityStatusPalErrorCode errorCode = done ? SecurityStatusPalErrorCode.CompleteNeeded : SecurityStatusPalErrorCode.ContinueNeeded;
                return new SecurityStatusPal(errorCode);
            }
            catch(Exception ex)
            {
                //TODO (Issue #5890): Print exception until issue is fixed
                Debug.Write("Exception Caught. - " + ex);
                if (GlobalLog.IsEnabled)
                {
                    GlobalLog.Print("Exception Caught. - " + ex);
                }

                return new SecurityStatusPal(SecurityStatusPalErrorCode.InternalError, ex);
            }
        }