_SSPIWrapper.cs source code in C# .NET

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/ Dotnetfx_Win7_3.5.1 / Dotnetfx_Win7_3.5.1 / 3.5.1 / DEVDIV / depot / DevDiv / releases / whidbey / NetFXspW7 / ndp / fx / src / Net / System / Net / _SSPIWrapper.cs / 2 / _SSPIWrapper.cs

                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Net { 
    using System.Runtime.InteropServices; 
    using System.Diagnostics;
    using System.ComponentModel; 
    using System.Net.Sockets;
    using System.Security.Permissions;
    using System.Globalization;
    using System.Net.Security; 

    internal static class SSPIWrapper { 
 
        internal static SecurityPackageInfoClass[] EnumerateSecurityPackages(SSPIInterface SecModule) {
            GlobalLog.Enter("EnumerateSecurityPackages"); 
            if (SecModule.SecurityPackages==null) {
                lock (SecModule) {
                    if (SecModule.SecurityPackages==null) {
                        int moduleCount = 0; 
                        SafeFreeContextBuffer arrayBaseHandle = null;
                        try { 
                            int errorCode = SecModule.EnumerateSecurityPackages(out moduleCount, out arrayBaseHandle); 
                            GlobalLog.Print("SSPIWrapper::arrayBase: " + (arrayBaseHandle.DangerousGetHandle().ToString("x")));
                            if (errorCode != 0) { 
                                throw new Win32Exception(errorCode);
                            }
                            SecurityPackageInfoClass[] securityPackages = new SecurityPackageInfoClass[moduleCount];
                            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_enumerating_security_packages)); 
                            int i;
                            for (i = 0; i < moduleCount; i++) { 
                                securityPackages[i] = new SecurityPackageInfoClass(arrayBaseHandle, i); 
                                if (Logging.On) Logging.PrintInfo(Logging.Web, "    " + securityPackages[i].Name);
                            } 
                            SecModule.SecurityPackages = securityPackages;
                        }
                        finally {
                            if (arrayBaseHandle != null) { 
                                arrayBaseHandle.Close();
                            } 
                        } 
                    }
                } 
            }
            GlobalLog.Leave("EnumerateSecurityPackages");
            return SecModule.SecurityPackages;
        } 

        internal static SecurityPackageInfoClass GetVerifyPackageInfo(SSPIInterface secModule, string packageName) { 
            return GetVerifyPackageInfo(secModule, packageName, false); 
        }
 
        internal static SecurityPackageInfoClass GetVerifyPackageInfo(SSPIInterface secModule, string packageName, bool throwIfMissing) {
            SecurityPackageInfoClass[] supportedSecurityPackages = EnumerateSecurityPackages(secModule);
            if (supportedSecurityPackages != null) {
                for (int i = 0; i < supportedSecurityPackages.Length; i++) { 
                    if (string.Compare(supportedSecurityPackages[i].Name, packageName, StringComparison.OrdinalIgnoreCase) == 0) {
                        return supportedSecurityPackages[i]; 
                    } 
                }
            } 

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_package_not_found, packageName));

            // error 
            if (throwIfMissing) {
                throw new NotSupportedException(SR.GetString(SR.net_securitypackagesupport)); 
            } 

            return null; 
        }

        public static SafeFreeCredentials AcquireDefaultCredential(SSPIInterface SecModule, string package, CredentialUse intent) {
            GlobalLog.Print("SSPIWrapper::AcquireDefaultCredential(): using " + package); 
            if (Logging.On) Logging.PrintInfo(Logging.Web,
                "AcquireDefaultCredential(" + 
                "package = " + package + ", " + 
                "intent  = " + intent + ")");
 

            SafeFreeCredentials outCredential = null;
            int errorCode = SecModule.AcquireDefaultCredential(package, intent, out outCredential );
 
            if (errorCode != 0) {
#if TRAVE 
                GlobalLog.Print("SSPIWrapper::AcquireDefaultCredential(): error " + SecureChannel.MapSecurityStatus((uint)errorCode)); 
#endif
                if (Logging.On) Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_failed_with_error, "AcquireDefaultCredential()", String.Format(CultureInfo.CurrentCulture, "0X{0:X}", errorCode))); 
                throw new Win32Exception(errorCode);
            }
            return outCredential;
        } 

        public static SafeFreeCredentials AcquireCredentialsHandle(SSPIInterface SecModule, string package, CredentialUse intent, ref AuthIdentity authdata) { 
            GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#2(): using " + package); 

            if (Logging.On) Logging.PrintInfo(Logging.Web, 
                "AcquireCredentialsHandle(" +
                "package  = " + package + ", " +
                "intent   = " + intent + ", " +
                "authdata = " + authdata + ")"); 

            SafeFreeCredentials credentialsHandle = null; 
            int errorCode = SecModule.AcquireCredentialsHandle(package, 
                                                               intent,
                                                               ref authdata, 
                                                               out credentialsHandle
                                                               );

            if (errorCode != 0) { 
#if TRAVE
                GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#2(): error " + SecureChannel.MapSecurityStatus((uint)errorCode)); 
#endif 
                if (Logging.On) Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_failed_with_error, "AcquireCredentialsHandle()", String.Format(CultureInfo.CurrentCulture, "0X{0:X}", errorCode)));
                throw new Win32Exception(errorCode); 
            }
            return credentialsHandle;
        }
 
        public static SafeFreeCredentials AcquireCredentialsHandle(SSPIInterface SecModule, string package, CredentialUse intent, SecureCredential scc) {
            GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#3(): using " + package); 
 
            if (Logging.On) Logging.PrintInfo(Logging.Web,
                "AcquireCredentialsHandle(" + 
                "package = " + package + ", " +
                "intent  = " + intent + ", " +
                "scc     = " + scc + ")");
 
            SafeFreeCredentials outCredential = null;
            int errorCode = SecModule.AcquireCredentialsHandle( 
                                            package, 
                                            intent,
                                            ref scc, 
                                            out outCredential
                                            );
             if (errorCode != 0) {
#if TRAVE 
                 GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#3(): error " + SecureChannel.MapSecurityStatus((uint)errorCode));
#endif 
                if (Logging.On) Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_failed_with_error, "AcquireCredentialsHandle()", String.Format(CultureInfo.CurrentCulture, "0X{0:X}", errorCode))); 
                 throw new Win32Exception(errorCode);
             } 

#if TRAVE
            GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#3(): cred handle = " + outCredential.ToString());
#endif 
            return outCredential;
        } 
 
        internal static int InitializeSecurityContext(SSPIInterface SecModule, ref SafeFreeCredentials credential, ref SafeDeleteContext context, string targetName, ContextFlags inFlags, Endianness datarep, SecurityBuffer inputBuffer, SecurityBuffer outputBuffer, ref ContextFlags outFlags) {
            if (Logging.On) Logging.PrintInfo(Logging.Web, 
                "InitializeSecurityContext(" +
                "credential = " + credential.ToString() + ", " +
                "context = " + ValidationHelper.ToString(context) + ", " +
                "targetName = " + targetName + ", " + 
                "inFlags = " + inFlags + ")");
 
            int errorCode = SecModule.InitializeSecurityContext(ref credential, ref context, targetName, inFlags, datarep, inputBuffer, outputBuffer, ref outFlags); 

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_context_input_buffer, "InitializeSecurityContext", (inputBuffer == null ? 0 : inputBuffer.size), outputBuffer.size, (SecurityStatus) errorCode)); 

            return errorCode;
        }
 
        internal static int InitializeSecurityContext(SSPIInterface SecModule, SafeFreeCredentials credential, ref SafeDeleteContext context, string targetName, ContextFlags inFlags, Endianness datarep, SecurityBuffer[] inputBuffers, SecurityBuffer outputBuffer, ref ContextFlags outFlags) {
            if (Logging.On) Logging.PrintInfo(Logging.Web, 
                "InitializeSecurityContext(" + 
                "credential = " + credential.ToString() + ", " +
                "context = " + ValidationHelper.ToString(context) + ", " + 
                "targetName = " + targetName + ", " +
                "inFlags = " + inFlags + ")");

            int errorCode = SecModule.InitializeSecurityContext(credential, ref context, targetName, inFlags, datarep, inputBuffers, outputBuffer, ref outFlags); 

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_context_input_buffers, "InitializeSecurityContext", (inputBuffers == null ? 0 : inputBuffers.Length), outputBuffer.size, (SecurityStatus) errorCode)); 
 
            return errorCode;
        } 

        internal static int AcceptSecurityContext(SSPIInterface SecModule, ref SafeFreeCredentials credential, ref SafeDeleteContext context, ContextFlags inFlags, Endianness datarep, SecurityBuffer inputBuffer, SecurityBuffer outputBuffer, ref ContextFlags outFlags)
        {
 
            if (Logging.On) Logging.PrintInfo(Logging.Web,
                "AcceptSecurityContext(" + 
                "credential = " + credential.ToString() + ", " + 
                "context = " + ValidationHelper.ToString(context) + ", " +
                "inFlags = " + inFlags + ")"); 

            int errorCode = SecModule.AcceptSecurityContext(ref credential, ref context, inputBuffer, inFlags, datarep, outputBuffer, ref outFlags);

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_context_input_buffer, "AcceptSecurityContext", (inputBuffer == null ? 0 : inputBuffer.size), outputBuffer.size, (SecurityStatus) errorCode)); 

            return errorCode; 
        } 

        internal static int AcceptSecurityContext(SSPIInterface SecModule, SafeFreeCredentials credential, ref SafeDeleteContext context, ContextFlags inFlags, Endianness datarep, SecurityBuffer[] inputBuffers, SecurityBuffer outputBuffer, ref ContextFlags outFlags) 
        {
            if (Logging.On) Logging.PrintInfo(Logging.Web,
                "AcceptSecurityContext(" +
                "credential = " + credential.ToString() + ", " + 
                "context = " + ValidationHelper.ToString(context) + ", " +
                "inFlags = " + inFlags + ")"); 
 
            int errorCode = SecModule.AcceptSecurityContext(credential, ref context, inputBuffers, inFlags, datarep, outputBuffer, ref outFlags);
 
            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_context_input_buffers, "AcceptSecurityContext", (inputBuffers == null ? 0 : inputBuffers.Length), outputBuffer.size, (SecurityStatus) errorCode));

            return errorCode;
        } 

        internal static int CompleteAuthToken(SSPIInterface SecModule, ref SafeDeleteContext context, SecurityBuffer[] inputBuffers) { 
            int errorCode = SecModule.CompleteAuthToken(ref context, inputBuffers); 

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_operation_returned_something, "CompleteAuthToken()", (SecurityStatus) errorCode)); 

            return errorCode;
        }
 
        public static int QuerySecurityContextToken(SSPIInterface SecModule, SafeDeleteContext context, out SafeCloseHandle token) {
            return SecModule.QuerySecurityContextToken(context, out token); 
        } 

        public static int EncryptMessage(SSPIInterface secModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber) { 
            return EncryptDecryptHelper(OP.Encrypt, secModule, context, input, sequenceNumber);
        }

        public static int DecryptMessage(SSPIInterface secModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber) { 
            return EncryptDecryptHelper(OP.Decrypt, secModule, context, input, sequenceNumber);
        } 
 
        internal static int MakeSignature(SSPIInterface secModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber) {
            return EncryptDecryptHelper(OP.MakeSignature, secModule, context, input, sequenceNumber); 
        }

        public static int VerifySignature(SSPIInterface secModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber) {
            return EncryptDecryptHelper(OP.VerifySignature, secModule, context, input, sequenceNumber); 
        }
 
        private enum OP { 
            Encrypt = 1,
            Decrypt, 
            MakeSignature,
            VerifySignature
        }
        // 
        private unsafe static int EncryptDecryptHelper(OP op, SSPIInterface SecModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber)
        { 
            SecurityBufferDescriptor sdcInOut = new SecurityBufferDescriptor(input.Length); 
            SecurityBufferStruct[] unmanagedBuffer  = new SecurityBufferStruct[input.Length];
 
            fixed (SecurityBufferStruct* unmanagedBufferPtr = unmanagedBuffer)
            {
                sdcInOut.UnmanagedPointer = unmanagedBufferPtr;
                GCHandle[] pinnedBuffers = new GCHandle[input.Length]; 
                byte[][] buffers = new byte[input.Length][];
                try 
                { 
                    for (int i = 0; i < input.Length; i++)
                    { 
                        SecurityBuffer iBuffer = input[i];
                        unmanagedBuffer[i].count = iBuffer.size;
                        unmanagedBuffer[i].type  = iBuffer.type;
                        if (iBuffer.token == null || iBuffer.token.Length == 0) 
                        {
                            unmanagedBuffer[i].token  = IntPtr.Zero; 
                        } 
                        else
                        { 
                            pinnedBuffers[i] = GCHandle.Alloc(iBuffer.token, GCHandleType.Pinned);
                            unmanagedBuffer[i].token = Marshal.UnsafeAddrOfPinnedArrayElement(iBuffer.token, iBuffer.offset);
                            buffers[i] = iBuffer.token;
                        } 
                    }
 
                    // The result is written in the input Buffer passed as type=BufferType.Data. 
                    int errorCode;
                    switch (op) 
                    {
                        case OP.Encrypt:
                            errorCode = SecModule.EncryptMessage(context, sdcInOut, sequenceNumber);
                            break; 

                        case OP.Decrypt: 
                            errorCode = SecModule.DecryptMessage(context, sdcInOut, sequenceNumber); 
                            break;
 
                        case OP.MakeSignature:
                            errorCode = SecModule.MakeSignature(context, sdcInOut, sequenceNumber);
                            break;
 
                        case OP.VerifySignature:
                            errorCode = SecModule.VerifySignature(context, sdcInOut, sequenceNumber); 
                            break; 

                        default: throw ExceptionHelper.MethodNotImplementedException; 
                    }

                    // Marshalling back returned sizes / data.
                    for (int i = 0; i < input.Length; i++) 
                    {
                        SecurityBuffer iBuffer = input[i]; 
                        iBuffer.size = unmanagedBuffer[i].count; 
                        iBuffer.type = unmanagedBuffer[i].type;
 
                        if (iBuffer.size == 0)
                        {
                            iBuffer.offset = 0;
                            iBuffer.token = null; 
                        }
                        else checked 
                        { 
                            // Find the buffer this is inside of.  Usually they all point inside buffer 0.
                            int j; 
                            for (j = 0; j < input.Length; j++)
                            {
                                if (buffers[j] == null)
                                { 
                                    continue;
                                } 
 
                                byte* bufferAddress = (byte*) Marshal.UnsafeAddrOfPinnedArrayElement(buffers[j], 0);
                                if ((byte*) unmanagedBuffer[i].token >= bufferAddress && 
                                    (byte*) unmanagedBuffer[i].token + iBuffer.size <= bufferAddress + buffers[j].Length)
                                {
                                    iBuffer.offset = (int) ((byte*) unmanagedBuffer[i].token - bufferAddress);
                                    iBuffer.token = buffers[j]; 
                                    break;
                                } 
                            } 

                            if (j >= input.Length) 
                            {
                                GlobalLog.Assert("SSPIWrapper::EncryptDecryptHelper", "Output buffer out of range.");
                                iBuffer.size = 0;
                                iBuffer.offset = 0; 
                                iBuffer.token = null;
                            } 
                        } 

                        // Backup validate the new sizes. 
                        GlobalLog.Assert(iBuffer.offset >= 0 && iBuffer.offset <= (iBuffer.token == null ? 0 : iBuffer.token.Length), "SSPIWrapper::EncryptDecryptHelper|'offset' out of range.  [{0}]", iBuffer.offset);
                        GlobalLog.Assert(iBuffer.size >= 0 && iBuffer.size <= (iBuffer.token == null ? 0 : iBuffer.token.Length - iBuffer.offset), "SSPIWrapper::EncryptDecryptHelper|'size' out of range.  [{0}]", iBuffer.size);
                    }
 
                    if (errorCode !=0)
                        if (Logging.On) 
                        { 
                            if (errorCode == 0x90321)
                                Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_returned_something, op, "SEC_I_RENEGOTIATE")); 
                            else
                                Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_failed_with_error, op, String.Format(CultureInfo.CurrentCulture, "0X{0:X}", errorCode)));
                        }
                    return errorCode; 
                }
                finally { 
                    for (int i = 0; i < pinnedBuffers.Length; ++i) { 
                        if (pinnedBuffers[i].IsAllocated) {
                            pinnedBuffers[i].Free(); 
                        }
                    }
                }
            } 
        }
 
        public static SafeFreeContextBufferChannelBinding QueryContextChannelBinding(SSPIInterface SecModule, SafeDeleteContext securityContext, ContextAttribute contextAttribute) 
        {
            GlobalLog.Enter("QueryContextChannelBinding", contextAttribute.ToString()); 

            SafeFreeContextBufferChannelBinding result;
            int errorCode = SecModule.QueryContextChannelBinding(securityContext, contextAttribute, out result);
            if (errorCode != 0) 
            {
                GlobalLog.Leave("QueryContextChannelBinding", "ERROR = " + ErrorDescription(errorCode)); 
                return null; 
            }
 
            GlobalLog.Leave("QueryContextChannelBinding", ValidationHelper.HashString(result));
            return result;
        }
 
        public static object QueryContextAttributes(SSPIInterface SecModule, SafeDeleteContext securityContext, ContextAttribute contextAttribute) {
            GlobalLog.Enter("QueryContextAttributes", contextAttribute.ToString()); 
 
            int nativeBlockSize = IntPtr.Size;
            Type    handleType = null; 

            switch (contextAttribute) {
                case ContextAttribute.Sizes:
                    nativeBlockSize = SecSizes.SizeOf; 
                    break;
                case ContextAttribute.StreamSizes: 
                    nativeBlockSize = StreamSizes.SizeOf; 
                    break;
 
                case ContextAttribute.Names:
                    handleType = typeof(SafeFreeContextBuffer);
                    break;
 
                case ContextAttribute.PackageInfo:
                    handleType = typeof(SafeFreeContextBuffer); 
                    break; 

                case ContextAttribute.NegotiationInfo: 
                    handleType = typeof(SafeFreeContextBuffer);
                    nativeBlockSize = Marshal.SizeOf(typeof(NegotiationInfo));
                    break;
 
                case ContextAttribute.ClientSpecifiedSpn:
                    handleType = typeof(SafeFreeContextBuffer); 
                    break; 

                case ContextAttribute.RemoteCertificate: 
                    handleType = typeof(SafeFreeCertContext);
                    break;

                case ContextAttribute.LocalCertificate: 
                    handleType = typeof(SafeFreeCertContext);
                    break; 
 
                case ContextAttribute.IssuerListInfoEx:
                    nativeBlockSize = Marshal.SizeOf(typeof(IssuerListInfoEx)); 
                    handleType = typeof(SafeFreeContextBuffer);
                    break;

                case ContextAttribute.ConnectionInfo: 
                    nativeBlockSize = Marshal.SizeOf(typeof(SslConnectionInfo));
                    break; 
 
                default:
                    throw new ArgumentException(SR.GetString(SR.net_invalid_enum, "ContextAttribute"), "contextAttribute"); 
            }

            SafeHandle SspiHandle = null;
            object attribute = null; 

            try { 
                byte[] nativeBuffer = new byte[nativeBlockSize]; 
                int errorCode = SecModule.QueryContextAttributes(securityContext, contextAttribute, nativeBuffer, handleType, out SspiHandle);
                if (errorCode != 0) { 
                    GlobalLog.Leave("Win32:QueryContextAttributes", "ERROR = " + ErrorDescription(errorCode));
                    return null;
                }
 
                switch (contextAttribute) {
                    case ContextAttribute.Sizes: 
                        attribute = new SecSizes(nativeBuffer); 
                        break;
 
                    case ContextAttribute.StreamSizes:
                        attribute = new StreamSizes(nativeBuffer);
                        break;
 
                    case ContextAttribute.Names:
                        if (ComNetOS.IsWin9x) { 
                            attribute = Marshal.PtrToStringAnsi(SspiHandle.DangerousGetHandle()); 
                        }
                        else { 
                            attribute = Marshal.PtrToStringUni(SspiHandle.DangerousGetHandle());
                        }
                        break;
 
                    case ContextAttribute.PackageInfo:
                        attribute = new SecurityPackageInfoClass(SspiHandle, 0); 
                        break; 

                    case ContextAttribute.NegotiationInfo: 
                        unsafe {
                            fixed (void* ptr=nativeBuffer) {
                                attribute = new NegotiationInfoClass(SspiHandle, Marshal.ReadInt32(new IntPtr(ptr), NegotiationInfo.NegotiationStateOffest));
                            } 
                        }
                        break; 
 
                    case ContextAttribute.ClientSpecifiedSpn:
                        attribute = Marshal.PtrToStringUni(SspiHandle.DangerousGetHandle()); 
                        break;

                    case ContextAttribute.LocalCertificate:
                        goto case ContextAttribute.RemoteCertificate; 
                    case ContextAttribute.RemoteCertificate:
                        attribute = SspiHandle; 
                        SspiHandle = null; 
                        break;
 
                    case ContextAttribute.IssuerListInfoEx:
                        attribute =  new IssuerListInfoEx(SspiHandle, nativeBuffer);
                        SspiHandle = null;
                        break; 

                    case ContextAttribute.ConnectionInfo: 
                        attribute = new SslConnectionInfo(nativeBuffer); 
                        break;
                    default: 
                        // will return null
                        break;
                }
            } 
            finally {
                if (SspiHandle != null) { 
                    SspiHandle.Close(); 
                }
            } 
            GlobalLog.Leave("QueryContextAttributes", ValidationHelper.ToString(attribute));
            return attribute;
        }
 
        public static string ErrorDescription(int errorCode) {
            if (errorCode == -1) { 
                return "An exception when invoking Win32 API"; 
            }
            switch ((SecurityStatus)errorCode) { 
                case SecurityStatus.InvalidHandle:
                    return "Invalid handle";
                case SecurityStatus.InvalidToken:
                    return "Invalid token"; 
                case SecurityStatus.ContinueNeeded:
                    return "Continue needed"; 
                case SecurityStatus.IncompleteMessage: 
                    return "Message incomplete";
                case SecurityStatus.WrongPrincipal: 
                    return "Wrong principal";
                case SecurityStatus.TargetUnknown:
                    return "Target unknown";
                case SecurityStatus.PackageNotFound: 
                    return "Package not found";
                case SecurityStatus.BufferNotEnough: 
                    return "Buffer not enough"; 
                case SecurityStatus.MessageAltered:
                    return "Message altered"; 
                case SecurityStatus.UntrustedRoot:
                    return "Untrusted root";
                default:
                    return "0x"+errorCode.ToString("x", NumberFormatInfo.InvariantInfo); 
            }
        } 
 
    } // class SSPIWrapper
 

    [StructLayout(LayoutKind.Sequential)]
    internal class StreamSizes {
 
        public int header;
        public int trailer; 
        public int maximumMessage; 
        public int buffersCount;
        public int blockSize; 

        internal unsafe StreamSizes(byte[] memory) {
            fixed(void* voidPtr = memory) {
                IntPtr unmanagedAddress = new IntPtr(voidPtr); 
                try
                { 
                    header         = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress)); 
                    trailer        = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 4));
                    maximumMessage = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 8)); 
                    buffersCount   = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 12));
                    blockSize      = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 16));
                }
                catch (OverflowException) 
                {
                    GlobalLog.Assert(false, "StreamSizes::.ctor", "Negative size."); 
                    throw; 
                }
            } 
        }
        public static readonly int SizeOf = Marshal.SizeOf(typeof(StreamSizes));
    }
 
    [StructLayout(LayoutKind.Sequential)]
    internal class SecSizes { 
 
        public readonly int MaxToken;
        public readonly int MaxSignature; 
        public readonly int BlockSize;
        public readonly int SecurityTrailer;

        internal unsafe SecSizes(byte[] memory) { 
            fixed(void* voidPtr = memory) {
                IntPtr unmanagedAddress = new IntPtr(voidPtr); 
                try 
                {
                    MaxToken        = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress)); 
                    MaxSignature    = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 4));
                    BlockSize       = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 8));
                    SecurityTrailer = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 12));
                } 
                catch (OverflowException)
                { 
                    GlobalLog.Assert(false, "SecSizes::.ctor", "Negative size."); 
                    throw;
                } 
            }
        }
        public static readonly int SizeOf = Marshal.SizeOf(typeof(SecSizes));
    } 

 
    //From Schannel.h 
    internal enum SchProtocols {
        Zero                = 0, 
        PctClient           = 0x00000002,
        PctServer           = 0x00000001,
        Pct                 = (PctClient | PctServer),
        Ssl2Client          = 0x00000008, 
        Ssl2Server          = 0x00000004,
        Ssl2                = (Ssl2Client | Ssl2Server), 
        Ssl3Client          = 0x00000020, 
        Ssl3Server          = 0x00000010,
        Ssl3                = (Ssl3Client | Ssl3Server), 
        TlsClient           = 0x00000080,
        TlsServer           = 0x00000040,
        Tls                 = (TlsClient | TlsServer),
        Ssl3Tls             = (Ssl3 | Tls), 
        UniClient           = unchecked((int)0x80000000),
        UniServer           = 0x40000000, 
        Unified             = (UniClient | UniServer), 
        ClientMask          = (PctClient | Ssl2Client | Ssl3Client | TlsClient |UniClient),
        ServerMask          = (PctServer | Ssl2Server | Ssl3Server | TlsServer |UniServer) 
    };

    //From WinCrypt.h
    [Flags] 
    internal enum Alg {
        Any             = 0, 
        ClassSignture   = (1 << 13), 
        ClassEncrypt    = (3 << 13),
        ClassHash       = (4 << 13), 
        ClassKeyXch     = (5 << 13),
        TypeRSA         = (2 << 9),
        TypeBlock       = (3 << 9),
        TypeStream      = (4 << 9), 
        TypeDH          = (5 << 9),
 
        NameDES         = 1, 
        NameRC2         = 2,
        Name3DES        = 3, 
        NameAES_128     = 14,
        NameAES_192     = 15,
        NameAES_256     = 16,
        NameAES         = 17, 

        NameRC4         = 1, 
 
        NameMD5         = 3,
        NameSHA         = 4, 

        NameDH_Ephem    = 2,
    }
 
    //From Schannel.h
    [StructLayout(LayoutKind.Sequential)] 
    internal class SslConnectionInfo { 
        public readonly int           Protocol;
        public readonly int           DataCipherAlg; 
        public readonly int           DataKeySize;
        public readonly int           DataHashAlg;
        public readonly int           DataHashKeySize;
        public readonly int           KeyExchangeAlg; 
        public readonly int           KeyExchKeySize;
 
        internal unsafe SslConnectionInfo(byte[] nativeBuffer) { 
            fixed(void* voidPtr = nativeBuffer) {
                IntPtr unmanagedAddress = new IntPtr(voidPtr); 
                Protocol        = Marshal.ReadInt32(unmanagedAddress);
                DataCipherAlg   = Marshal.ReadInt32(unmanagedAddress, 4);
                DataKeySize     = Marshal.ReadInt32(unmanagedAddress, 8);
                DataHashAlg     = Marshal.ReadInt32(unmanagedAddress, 12); 
                DataHashKeySize = Marshal.ReadInt32(unmanagedAddress, 16);
                KeyExchangeAlg  = Marshal.ReadInt32(unmanagedAddress, 20); 
                KeyExchKeySize  = Marshal.ReadInt32(unmanagedAddress, 24); 
            }
        } 
    }

    [StructLayout(LayoutKind.Sequential)]
    internal struct NegotiationInfo { 
        // see SecPkgContext_NegotiationInfoW in 
 
        // [MarshalAs(UnmanagedType.LPStruct)] internal SecurityPackageInfo PackageInfo; 
        internal IntPtr PackageInfo;
        internal uint NegotiationState; 
        internal static readonly int Size = Marshal.SizeOf(typeof(NegotiationInfo));
        internal static readonly int NegotiationStateOffest = (int)Marshal.OffsetOf(typeof(NegotiationInfo), "NegotiationState");
    }
 
    // we keep it simple since we use this only to know if NTLM or
    // Kerberos are used in the context of a Negotiate handshake 
    internal class NegotiationInfoClass { 
        internal const string NTLM      = "NTLM";
        internal const string Kerberos  = "Kerberos"; 
        internal const string WDigest   = "WDigest";
        internal const string Negotiate = "Negotiate";
        internal string AuthenticationPackage;
 
        internal NegotiationInfoClass(SafeHandle safeHandle, int negotiationState) {
            if (safeHandle.IsInvalid) { 
                GlobalLog.Print("NegotiationInfoClass::.ctor() the handle is invalid:" + (safeHandle.DangerousGetHandle()).ToString("x")); 
                return;
            } 
            IntPtr packageInfo = safeHandle.DangerousGetHandle();
            GlobalLog.Print("NegotiationInfoClass::.ctor() packageInfo:" + packageInfo.ToString("x8") + " negotiationState:" + negotiationState.ToString("x8"));

            const int SECPKG_NEGOTIATION_COMPLETE           = 0; 
            const int SECPKG_NEGOTIATION_OPTIMISTIC         = 1;
            // const int SECPKG_NEGOTIATION_IN_PROGRESS     = 2; 
            // const int SECPKG_NEGOTIATION_DIRECT          = 3; 
            // const int SECPKG_NEGOTIATION_TRY_MULTICRED   = 4;
 
            if (negotiationState==SECPKG_NEGOTIATION_COMPLETE || negotiationState==SECPKG_NEGOTIATION_OPTIMISTIC) {
                IntPtr unmanagedString = Marshal.ReadIntPtr(packageInfo, SecurityPackageInfo.NameOffest);
                string name = null;
                if (unmanagedString!=IntPtr.Zero) { 
                    name = ComNetOS.IsWin9x ? Marshal.PtrToStringAnsi(unmanagedString) : Marshal.PtrToStringUni(unmanagedString);
                } 
                GlobalLog.Print("NegotiationInfoClass::.ctor() packageInfo:" + packageInfo.ToString("x8") + " negotiationState:" + negotiationState.ToString("x8") + " name:" + ValidationHelper.ToString(name)); 

                // an optimization for future string comparisons 
                if (string.Compare(name, Kerberos, StringComparison.OrdinalIgnoreCase)==0) {
                    AuthenticationPackage = Kerberos;
                }
                else if (string.Compare(name, NTLM, StringComparison.OrdinalIgnoreCase)==0) { 
                    AuthenticationPackage = NTLM;
                } 
                else if (string.Compare(name, WDigest, StringComparison.OrdinalIgnoreCase)==0) { 
                    AuthenticationPackage = WDigest;
                } 
                else {
                    AuthenticationPackage = name;
                }
            } 
        }
    } 
 
    [StructLayout(LayoutKind.Sequential)]
    internal struct SecurityPackageInfo { 
        // see SecPkgInfoW in 
        internal int Capabilities;
        internal short Version;
        internal short RPCID; 
        internal int MaxToken;
        internal IntPtr Name; 
        internal IntPtr Comment; 

        internal static readonly int Size = Marshal.SizeOf(typeof(SecurityPackageInfo)); 
        internal static readonly int NameOffest = (int)Marshal.OffsetOf(typeof(SecurityPackageInfo), "Name");
    }

    internal class SecurityPackageInfoClass { 
        internal int Capabilities = 0;
        internal short Version = 0; 
        internal short RPCID = 0; 
        internal int MaxToken = 0;
        internal string Name = null; 
        internal string Comment = null;

        /*
         *  This is to support SSL under semi trusted enviornment. 
         *  Note that it is only for SSL with no client cert
         */ 
        internal SecurityPackageInfoClass(SafeHandle safeHandle, int index) { 
            if (safeHandle.IsInvalid) {
                GlobalLog.Print("SecurityPackageInfoClass::.ctor() the pointer is invalid: " + (safeHandle.DangerousGetHandle()).ToString("x")); 
                return;
            }
            IntPtr unmanagedAddress = IntPtrHelper.Add(safeHandle.DangerousGetHandle(), SecurityPackageInfo.Size * index);
            GlobalLog.Print("SecurityPackageInfoClass::.ctor() unmanagedPointer: " + ((long)unmanagedAddress).ToString("x")); 

            Capabilities = Marshal.ReadInt32(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"Capabilities")); 
            Version = Marshal.ReadInt16(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"Version")); 
            RPCID = Marshal.ReadInt16(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"RPCID"));
            MaxToken = Marshal.ReadInt32(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"MaxToken")); 

            IntPtr unmanagedString;

            unmanagedString = Marshal.ReadIntPtr(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"Name")); 
            if (unmanagedString != IntPtr.Zero) {
                if (ComNetOS.IsWin9x) { 
                    Name = Marshal.PtrToStringAnsi(unmanagedString); 
                }
                else { 
                    Name = Marshal.PtrToStringUni(unmanagedString);
                }
                GlobalLog.Print("Name: " + Name);
            } 

            unmanagedString = Marshal.ReadIntPtr(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"Comment")); 
            if (unmanagedString != IntPtr.Zero) { 
                if (ComNetOS.IsWin9x) {
                    Comment = Marshal.PtrToStringAnsi(unmanagedString); 
                }
                else {
                    Comment = Marshal.PtrToStringUni(unmanagedString);
                } 
                GlobalLog.Print("Comment: " + Comment);
            } 
 
            GlobalLog.Print("SecurityPackageInfoClass::.ctor(): " + ToString());
        } 

        public override string ToString() {
            return  "Capabilities:" + String.Format(CultureInfo.InvariantCulture, "0x{0:x}", Capabilities)
                + " Version:" + Version.ToString(NumberFormatInfo.InvariantInfo) 
                + " RPCID:" + RPCID.ToString(NumberFormatInfo.InvariantInfo)
                + " MaxToken:" + MaxToken.ToString(NumberFormatInfo.InvariantInfo) 
                + " Name:" + ((Name==null)?"(null)":Name) 
                + " Comment:" + ((Comment==null)?"(null)":Comment
                ); 
        }
    }

    [StructLayout(LayoutKind.Sequential)] 
    internal struct Bindings {
        // see SecPkgContext_Bindings in  
        internal int BindingsLength; 
        internal IntPtr pBindings;
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Net { 
    using System.Runtime.InteropServices; 
    using System.Diagnostics;
    using System.ComponentModel; 
    using System.Net.Sockets;
    using System.Security.Permissions;
    using System.Globalization;
    using System.Net.Security; 

    internal static class SSPIWrapper { 
 
        internal static SecurityPackageInfoClass[] EnumerateSecurityPackages(SSPIInterface SecModule) {
            GlobalLog.Enter("EnumerateSecurityPackages"); 
            if (SecModule.SecurityPackages==null) {
                lock (SecModule) {
                    if (SecModule.SecurityPackages==null) {
                        int moduleCount = 0; 
                        SafeFreeContextBuffer arrayBaseHandle = null;
                        try { 
                            int errorCode = SecModule.EnumerateSecurityPackages(out moduleCount, out arrayBaseHandle); 
                            GlobalLog.Print("SSPIWrapper::arrayBase: " + (arrayBaseHandle.DangerousGetHandle().ToString("x")));
                            if (errorCode != 0) { 
                                throw new Win32Exception(errorCode);
                            }
                            SecurityPackageInfoClass[] securityPackages = new SecurityPackageInfoClass[moduleCount];
                            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_enumerating_security_packages)); 
                            int i;
                            for (i = 0; i < moduleCount; i++) { 
                                securityPackages[i] = new SecurityPackageInfoClass(arrayBaseHandle, i); 
                                if (Logging.On) Logging.PrintInfo(Logging.Web, "    " + securityPackages[i].Name);
                            } 
                            SecModule.SecurityPackages = securityPackages;
                        }
                        finally {
                            if (arrayBaseHandle != null) { 
                                arrayBaseHandle.Close();
                            } 
                        } 
                    }
                } 
            }
            GlobalLog.Leave("EnumerateSecurityPackages");
            return SecModule.SecurityPackages;
        } 

        internal static SecurityPackageInfoClass GetVerifyPackageInfo(SSPIInterface secModule, string packageName) { 
            return GetVerifyPackageInfo(secModule, packageName, false); 
        }
 
        internal static SecurityPackageInfoClass GetVerifyPackageInfo(SSPIInterface secModule, string packageName, bool throwIfMissing) {
            SecurityPackageInfoClass[] supportedSecurityPackages = EnumerateSecurityPackages(secModule);
            if (supportedSecurityPackages != null) {
                for (int i = 0; i < supportedSecurityPackages.Length; i++) { 
                    if (string.Compare(supportedSecurityPackages[i].Name, packageName, StringComparison.OrdinalIgnoreCase) == 0) {
                        return supportedSecurityPackages[i]; 
                    } 
                }
            } 

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_package_not_found, packageName));

            // error 
            if (throwIfMissing) {
                throw new NotSupportedException(SR.GetString(SR.net_securitypackagesupport)); 
            } 

            return null; 
        }

        public static SafeFreeCredentials AcquireDefaultCredential(SSPIInterface SecModule, string package, CredentialUse intent) {
            GlobalLog.Print("SSPIWrapper::AcquireDefaultCredential(): using " + package); 
            if (Logging.On) Logging.PrintInfo(Logging.Web,
                "AcquireDefaultCredential(" + 
                "package = " + package + ", " + 
                "intent  = " + intent + ")");
 

            SafeFreeCredentials outCredential = null;
            int errorCode = SecModule.AcquireDefaultCredential(package, intent, out outCredential );
 
            if (errorCode != 0) {
#if TRAVE 
                GlobalLog.Print("SSPIWrapper::AcquireDefaultCredential(): error " + SecureChannel.MapSecurityStatus((uint)errorCode)); 
#endif
                if (Logging.On) Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_failed_with_error, "AcquireDefaultCredential()", String.Format(CultureInfo.CurrentCulture, "0X{0:X}", errorCode))); 
                throw new Win32Exception(errorCode);
            }
            return outCredential;
        } 

        public static SafeFreeCredentials AcquireCredentialsHandle(SSPIInterface SecModule, string package, CredentialUse intent, ref AuthIdentity authdata) { 
            GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#2(): using " + package); 

            if (Logging.On) Logging.PrintInfo(Logging.Web, 
                "AcquireCredentialsHandle(" +
                "package  = " + package + ", " +
                "intent   = " + intent + ", " +
                "authdata = " + authdata + ")"); 

            SafeFreeCredentials credentialsHandle = null; 
            int errorCode = SecModule.AcquireCredentialsHandle(package, 
                                                               intent,
                                                               ref authdata, 
                                                               out credentialsHandle
                                                               );

            if (errorCode != 0) { 
#if TRAVE
                GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#2(): error " + SecureChannel.MapSecurityStatus((uint)errorCode)); 
#endif 
                if (Logging.On) Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_failed_with_error, "AcquireCredentialsHandle()", String.Format(CultureInfo.CurrentCulture, "0X{0:X}", errorCode)));
                throw new Win32Exception(errorCode); 
            }
            return credentialsHandle;
        }
 
        public static SafeFreeCredentials AcquireCredentialsHandle(SSPIInterface SecModule, string package, CredentialUse intent, SecureCredential scc) {
            GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#3(): using " + package); 
 
            if (Logging.On) Logging.PrintInfo(Logging.Web,
                "AcquireCredentialsHandle(" + 
                "package = " + package + ", " +
                "intent  = " + intent + ", " +
                "scc     = " + scc + ")");
 
            SafeFreeCredentials outCredential = null;
            int errorCode = SecModule.AcquireCredentialsHandle( 
                                            package, 
                                            intent,
                                            ref scc, 
                                            out outCredential
                                            );
             if (errorCode != 0) {
#if TRAVE 
                 GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#3(): error " + SecureChannel.MapSecurityStatus((uint)errorCode));
#endif 
                if (Logging.On) Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_failed_with_error, "AcquireCredentialsHandle()", String.Format(CultureInfo.CurrentCulture, "0X{0:X}", errorCode))); 
                 throw new Win32Exception(errorCode);
             } 

#if TRAVE
            GlobalLog.Print("SSPIWrapper::AcquireCredentialsHandle#3(): cred handle = " + outCredential.ToString());
#endif 
            return outCredential;
        } 
 
        internal static int InitializeSecurityContext(SSPIInterface SecModule, ref SafeFreeCredentials credential, ref SafeDeleteContext context, string targetName, ContextFlags inFlags, Endianness datarep, SecurityBuffer inputBuffer, SecurityBuffer outputBuffer, ref ContextFlags outFlags) {
            if (Logging.On) Logging.PrintInfo(Logging.Web, 
                "InitializeSecurityContext(" +
                "credential = " + credential.ToString() + ", " +
                "context = " + ValidationHelper.ToString(context) + ", " +
                "targetName = " + targetName + ", " + 
                "inFlags = " + inFlags + ")");
 
            int errorCode = SecModule.InitializeSecurityContext(ref credential, ref context, targetName, inFlags, datarep, inputBuffer, outputBuffer, ref outFlags); 

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_context_input_buffer, "InitializeSecurityContext", (inputBuffer == null ? 0 : inputBuffer.size), outputBuffer.size, (SecurityStatus) errorCode)); 

            return errorCode;
        }
 
        internal static int InitializeSecurityContext(SSPIInterface SecModule, SafeFreeCredentials credential, ref SafeDeleteContext context, string targetName, ContextFlags inFlags, Endianness datarep, SecurityBuffer[] inputBuffers, SecurityBuffer outputBuffer, ref ContextFlags outFlags) {
            if (Logging.On) Logging.PrintInfo(Logging.Web, 
                "InitializeSecurityContext(" + 
                "credential = " + credential.ToString() + ", " +
                "context = " + ValidationHelper.ToString(context) + ", " + 
                "targetName = " + targetName + ", " +
                "inFlags = " + inFlags + ")");

            int errorCode = SecModule.InitializeSecurityContext(credential, ref context, targetName, inFlags, datarep, inputBuffers, outputBuffer, ref outFlags); 

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_context_input_buffers, "InitializeSecurityContext", (inputBuffers == null ? 0 : inputBuffers.Length), outputBuffer.size, (SecurityStatus) errorCode)); 
 
            return errorCode;
        } 

        internal static int AcceptSecurityContext(SSPIInterface SecModule, ref SafeFreeCredentials credential, ref SafeDeleteContext context, ContextFlags inFlags, Endianness datarep, SecurityBuffer inputBuffer, SecurityBuffer outputBuffer, ref ContextFlags outFlags)
        {
 
            if (Logging.On) Logging.PrintInfo(Logging.Web,
                "AcceptSecurityContext(" + 
                "credential = " + credential.ToString() + ", " + 
                "context = " + ValidationHelper.ToString(context) + ", " +
                "inFlags = " + inFlags + ")"); 

            int errorCode = SecModule.AcceptSecurityContext(ref credential, ref context, inputBuffer, inFlags, datarep, outputBuffer, ref outFlags);

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_context_input_buffer, "AcceptSecurityContext", (inputBuffer == null ? 0 : inputBuffer.size), outputBuffer.size, (SecurityStatus) errorCode)); 

            return errorCode; 
        } 

        internal static int AcceptSecurityContext(SSPIInterface SecModule, SafeFreeCredentials credential, ref SafeDeleteContext context, ContextFlags inFlags, Endianness datarep, SecurityBuffer[] inputBuffers, SecurityBuffer outputBuffer, ref ContextFlags outFlags) 
        {
            if (Logging.On) Logging.PrintInfo(Logging.Web,
                "AcceptSecurityContext(" +
                "credential = " + credential.ToString() + ", " + 
                "context = " + ValidationHelper.ToString(context) + ", " +
                "inFlags = " + inFlags + ")"); 
 
            int errorCode = SecModule.AcceptSecurityContext(credential, ref context, inputBuffers, inFlags, datarep, outputBuffer, ref outFlags);
 
            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_sspi_security_context_input_buffers, "AcceptSecurityContext", (inputBuffers == null ? 0 : inputBuffers.Length), outputBuffer.size, (SecurityStatus) errorCode));

            return errorCode;
        } 

        internal static int CompleteAuthToken(SSPIInterface SecModule, ref SafeDeleteContext context, SecurityBuffer[] inputBuffers) { 
            int errorCode = SecModule.CompleteAuthToken(ref context, inputBuffers); 

            if (Logging.On) Logging.PrintInfo(Logging.Web, SR.GetString(SR.net_log_operation_returned_something, "CompleteAuthToken()", (SecurityStatus) errorCode)); 

            return errorCode;
        }
 
        public static int QuerySecurityContextToken(SSPIInterface SecModule, SafeDeleteContext context, out SafeCloseHandle token) {
            return SecModule.QuerySecurityContextToken(context, out token); 
        } 

        public static int EncryptMessage(SSPIInterface secModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber) { 
            return EncryptDecryptHelper(OP.Encrypt, secModule, context, input, sequenceNumber);
        }

        public static int DecryptMessage(SSPIInterface secModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber) { 
            return EncryptDecryptHelper(OP.Decrypt, secModule, context, input, sequenceNumber);
        } 
 
        internal static int MakeSignature(SSPIInterface secModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber) {
            return EncryptDecryptHelper(OP.MakeSignature, secModule, context, input, sequenceNumber); 
        }

        public static int VerifySignature(SSPIInterface secModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber) {
            return EncryptDecryptHelper(OP.VerifySignature, secModule, context, input, sequenceNumber); 
        }
 
        private enum OP { 
            Encrypt = 1,
            Decrypt, 
            MakeSignature,
            VerifySignature
        }
        // 
        private unsafe static int EncryptDecryptHelper(OP op, SSPIInterface SecModule, SafeDeleteContext context, SecurityBuffer[] input, uint sequenceNumber)
        { 
            SecurityBufferDescriptor sdcInOut = new SecurityBufferDescriptor(input.Length); 
            SecurityBufferStruct[] unmanagedBuffer  = new SecurityBufferStruct[input.Length];
 
            fixed (SecurityBufferStruct* unmanagedBufferPtr = unmanagedBuffer)
            {
                sdcInOut.UnmanagedPointer = unmanagedBufferPtr;
                GCHandle[] pinnedBuffers = new GCHandle[input.Length]; 
                byte[][] buffers = new byte[input.Length][];
                try 
                { 
                    for (int i = 0; i < input.Length; i++)
                    { 
                        SecurityBuffer iBuffer = input[i];
                        unmanagedBuffer[i].count = iBuffer.size;
                        unmanagedBuffer[i].type  = iBuffer.type;
                        if (iBuffer.token == null || iBuffer.token.Length == 0) 
                        {
                            unmanagedBuffer[i].token  = IntPtr.Zero; 
                        } 
                        else
                        { 
                            pinnedBuffers[i] = GCHandle.Alloc(iBuffer.token, GCHandleType.Pinned);
                            unmanagedBuffer[i].token = Marshal.UnsafeAddrOfPinnedArrayElement(iBuffer.token, iBuffer.offset);
                            buffers[i] = iBuffer.token;
                        } 
                    }
 
                    // The result is written in the input Buffer passed as type=BufferType.Data. 
                    int errorCode;
                    switch (op) 
                    {
                        case OP.Encrypt:
                            errorCode = SecModule.EncryptMessage(context, sdcInOut, sequenceNumber);
                            break; 

                        case OP.Decrypt: 
                            errorCode = SecModule.DecryptMessage(context, sdcInOut, sequenceNumber); 
                            break;
 
                        case OP.MakeSignature:
                            errorCode = SecModule.MakeSignature(context, sdcInOut, sequenceNumber);
                            break;
 
                        case OP.VerifySignature:
                            errorCode = SecModule.VerifySignature(context, sdcInOut, sequenceNumber); 
                            break; 

                        default: throw ExceptionHelper.MethodNotImplementedException; 
                    }

                    // Marshalling back returned sizes / data.
                    for (int i = 0; i < input.Length; i++) 
                    {
                        SecurityBuffer iBuffer = input[i]; 
                        iBuffer.size = unmanagedBuffer[i].count; 
                        iBuffer.type = unmanagedBuffer[i].type;
 
                        if (iBuffer.size == 0)
                        {
                            iBuffer.offset = 0;
                            iBuffer.token = null; 
                        }
                        else checked 
                        { 
                            // Find the buffer this is inside of.  Usually they all point inside buffer 0.
                            int j; 
                            for (j = 0; j < input.Length; j++)
                            {
                                if (buffers[j] == null)
                                { 
                                    continue;
                                } 
 
                                byte* bufferAddress = (byte*) Marshal.UnsafeAddrOfPinnedArrayElement(buffers[j], 0);
                                if ((byte*) unmanagedBuffer[i].token >= bufferAddress && 
                                    (byte*) unmanagedBuffer[i].token + iBuffer.size <= bufferAddress + buffers[j].Length)
                                {
                                    iBuffer.offset = (int) ((byte*) unmanagedBuffer[i].token - bufferAddress);
                                    iBuffer.token = buffers[j]; 
                                    break;
                                } 
                            } 

                            if (j >= input.Length) 
                            {
                                GlobalLog.Assert("SSPIWrapper::EncryptDecryptHelper", "Output buffer out of range.");
                                iBuffer.size = 0;
                                iBuffer.offset = 0; 
                                iBuffer.token = null;
                            } 
                        } 

                        // Backup validate the new sizes. 
                        GlobalLog.Assert(iBuffer.offset >= 0 && iBuffer.offset <= (iBuffer.token == null ? 0 : iBuffer.token.Length), "SSPIWrapper::EncryptDecryptHelper|'offset' out of range.  [{0}]", iBuffer.offset);
                        GlobalLog.Assert(iBuffer.size >= 0 && iBuffer.size <= (iBuffer.token == null ? 0 : iBuffer.token.Length - iBuffer.offset), "SSPIWrapper::EncryptDecryptHelper|'size' out of range.  [{0}]", iBuffer.size);
                    }
 
                    if (errorCode !=0)
                        if (Logging.On) 
                        { 
                            if (errorCode == 0x90321)
                                Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_returned_something, op, "SEC_I_RENEGOTIATE")); 
                            else
                                Logging.PrintError(Logging.Web, SR.GetString(SR.net_log_operation_failed_with_error, op, String.Format(CultureInfo.CurrentCulture, "0X{0:X}", errorCode)));
                        }
                    return errorCode; 
                }
                finally { 
                    for (int i = 0; i < pinnedBuffers.Length; ++i) { 
                        if (pinnedBuffers[i].IsAllocated) {
                            pinnedBuffers[i].Free(); 
                        }
                    }
                }
            } 
        }
 
        public static SafeFreeContextBufferChannelBinding QueryContextChannelBinding(SSPIInterface SecModule, SafeDeleteContext securityContext, ContextAttribute contextAttribute) 
        {
            GlobalLog.Enter("QueryContextChannelBinding", contextAttribute.ToString()); 

            SafeFreeContextBufferChannelBinding result;
            int errorCode = SecModule.QueryContextChannelBinding(securityContext, contextAttribute, out result);
            if (errorCode != 0) 
            {
                GlobalLog.Leave("QueryContextChannelBinding", "ERROR = " + ErrorDescription(errorCode)); 
                return null; 
            }
 
            GlobalLog.Leave("QueryContextChannelBinding", ValidationHelper.HashString(result));
            return result;
        }
 
        public static object QueryContextAttributes(SSPIInterface SecModule, SafeDeleteContext securityContext, ContextAttribute contextAttribute) {
            GlobalLog.Enter("QueryContextAttributes", contextAttribute.ToString()); 
 
            int nativeBlockSize = IntPtr.Size;
            Type    handleType = null; 

            switch (contextAttribute) {
                case ContextAttribute.Sizes:
                    nativeBlockSize = SecSizes.SizeOf; 
                    break;
                case ContextAttribute.StreamSizes: 
                    nativeBlockSize = StreamSizes.SizeOf; 
                    break;
 
                case ContextAttribute.Names:
                    handleType = typeof(SafeFreeContextBuffer);
                    break;
 
                case ContextAttribute.PackageInfo:
                    handleType = typeof(SafeFreeContextBuffer); 
                    break; 

                case ContextAttribute.NegotiationInfo: 
                    handleType = typeof(SafeFreeContextBuffer);
                    nativeBlockSize = Marshal.SizeOf(typeof(NegotiationInfo));
                    break;
 
                case ContextAttribute.ClientSpecifiedSpn:
                    handleType = typeof(SafeFreeContextBuffer); 
                    break; 

                case ContextAttribute.RemoteCertificate: 
                    handleType = typeof(SafeFreeCertContext);
                    break;

                case ContextAttribute.LocalCertificate: 
                    handleType = typeof(SafeFreeCertContext);
                    break; 
 
                case ContextAttribute.IssuerListInfoEx:
                    nativeBlockSize = Marshal.SizeOf(typeof(IssuerListInfoEx)); 
                    handleType = typeof(SafeFreeContextBuffer);
                    break;

                case ContextAttribute.ConnectionInfo: 
                    nativeBlockSize = Marshal.SizeOf(typeof(SslConnectionInfo));
                    break; 
 
                default:
                    throw new ArgumentException(SR.GetString(SR.net_invalid_enum, "ContextAttribute"), "contextAttribute"); 
            }

            SafeHandle SspiHandle = null;
            object attribute = null; 

            try { 
                byte[] nativeBuffer = new byte[nativeBlockSize]; 
                int errorCode = SecModule.QueryContextAttributes(securityContext, contextAttribute, nativeBuffer, handleType, out SspiHandle);
                if (errorCode != 0) { 
                    GlobalLog.Leave("Win32:QueryContextAttributes", "ERROR = " + ErrorDescription(errorCode));
                    return null;
                }
 
                switch (contextAttribute) {
                    case ContextAttribute.Sizes: 
                        attribute = new SecSizes(nativeBuffer); 
                        break;
 
                    case ContextAttribute.StreamSizes:
                        attribute = new StreamSizes(nativeBuffer);
                        break;
 
                    case ContextAttribute.Names:
                        if (ComNetOS.IsWin9x) { 
                            attribute = Marshal.PtrToStringAnsi(SspiHandle.DangerousGetHandle()); 
                        }
                        else { 
                            attribute = Marshal.PtrToStringUni(SspiHandle.DangerousGetHandle());
                        }
                        break;
 
                    case ContextAttribute.PackageInfo:
                        attribute = new SecurityPackageInfoClass(SspiHandle, 0); 
                        break; 

                    case ContextAttribute.NegotiationInfo: 
                        unsafe {
                            fixed (void* ptr=nativeBuffer) {
                                attribute = new NegotiationInfoClass(SspiHandle, Marshal.ReadInt32(new IntPtr(ptr), NegotiationInfo.NegotiationStateOffest));
                            } 
                        }
                        break; 
 
                    case ContextAttribute.ClientSpecifiedSpn:
                        attribute = Marshal.PtrToStringUni(SspiHandle.DangerousGetHandle()); 
                        break;

                    case ContextAttribute.LocalCertificate:
                        goto case ContextAttribute.RemoteCertificate; 
                    case ContextAttribute.RemoteCertificate:
                        attribute = SspiHandle; 
                        SspiHandle = null; 
                        break;
 
                    case ContextAttribute.IssuerListInfoEx:
                        attribute =  new IssuerListInfoEx(SspiHandle, nativeBuffer);
                        SspiHandle = null;
                        break; 

                    case ContextAttribute.ConnectionInfo: 
                        attribute = new SslConnectionInfo(nativeBuffer); 
                        break;
                    default: 
                        // will return null
                        break;
                }
            } 
            finally {
                if (SspiHandle != null) { 
                    SspiHandle.Close(); 
                }
            } 
            GlobalLog.Leave("QueryContextAttributes", ValidationHelper.ToString(attribute));
            return attribute;
        }
 
        public static string ErrorDescription(int errorCode) {
            if (errorCode == -1) { 
                return "An exception when invoking Win32 API"; 
            }
            switch ((SecurityStatus)errorCode) { 
                case SecurityStatus.InvalidHandle:
                    return "Invalid handle";
                case SecurityStatus.InvalidToken:
                    return "Invalid token"; 
                case SecurityStatus.ContinueNeeded:
                    return "Continue needed"; 
                case SecurityStatus.IncompleteMessage: 
                    return "Message incomplete";
                case SecurityStatus.WrongPrincipal: 
                    return "Wrong principal";
                case SecurityStatus.TargetUnknown:
                    return "Target unknown";
                case SecurityStatus.PackageNotFound: 
                    return "Package not found";
                case SecurityStatus.BufferNotEnough: 
                    return "Buffer not enough"; 
                case SecurityStatus.MessageAltered:
                    return "Message altered"; 
                case SecurityStatus.UntrustedRoot:
                    return "Untrusted root";
                default:
                    return "0x"+errorCode.ToString("x", NumberFormatInfo.InvariantInfo); 
            }
        } 
 
    } // class SSPIWrapper
 

    [StructLayout(LayoutKind.Sequential)]
    internal class StreamSizes {
 
        public int header;
        public int trailer; 
        public int maximumMessage; 
        public int buffersCount;
        public int blockSize; 

        internal unsafe StreamSizes(byte[] memory) {
            fixed(void* voidPtr = memory) {
                IntPtr unmanagedAddress = new IntPtr(voidPtr); 
                try
                { 
                    header         = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress)); 
                    trailer        = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 4));
                    maximumMessage = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 8)); 
                    buffersCount   = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 12));
                    blockSize      = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 16));
                }
                catch (OverflowException) 
                {
                    GlobalLog.Assert(false, "StreamSizes::.ctor", "Negative size."); 
                    throw; 
                }
            } 
        }
        public static readonly int SizeOf = Marshal.SizeOf(typeof(StreamSizes));
    }
 
    [StructLayout(LayoutKind.Sequential)]
    internal class SecSizes { 
 
        public readonly int MaxToken;
        public readonly int MaxSignature; 
        public readonly int BlockSize;
        public readonly int SecurityTrailer;

        internal unsafe SecSizes(byte[] memory) { 
            fixed(void* voidPtr = memory) {
                IntPtr unmanagedAddress = new IntPtr(voidPtr); 
                try 
                {
                    MaxToken        = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress)); 
                    MaxSignature    = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 4));
                    BlockSize       = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 8));
                    SecurityTrailer = (int) checked((uint) Marshal.ReadInt32(unmanagedAddress, 12));
                } 
                catch (OverflowException)
                { 
                    GlobalLog.Assert(false, "SecSizes::.ctor", "Negative size."); 
                    throw;
                } 
            }
        }
        public static readonly int SizeOf = Marshal.SizeOf(typeof(SecSizes));
    } 

 
    //From Schannel.h 
    internal enum SchProtocols {
        Zero                = 0, 
        PctClient           = 0x00000002,
        PctServer           = 0x00000001,
        Pct                 = (PctClient | PctServer),
        Ssl2Client          = 0x00000008, 
        Ssl2Server          = 0x00000004,
        Ssl2                = (Ssl2Client | Ssl2Server), 
        Ssl3Client          = 0x00000020, 
        Ssl3Server          = 0x00000010,
        Ssl3                = (Ssl3Client | Ssl3Server), 
        TlsClient           = 0x00000080,
        TlsServer           = 0x00000040,
        Tls                 = (TlsClient | TlsServer),
        Ssl3Tls             = (Ssl3 | Tls), 
        UniClient           = unchecked((int)0x80000000),
        UniServer           = 0x40000000, 
        Unified             = (UniClient | UniServer), 
        ClientMask          = (PctClient | Ssl2Client | Ssl3Client | TlsClient |UniClient),
        ServerMask          = (PctServer | Ssl2Server | Ssl3Server | TlsServer |UniServer) 
    };

    //From WinCrypt.h
    [Flags] 
    internal enum Alg {
        Any             = 0, 
        ClassSignture   = (1 << 13), 
        ClassEncrypt    = (3 << 13),
        ClassHash       = (4 << 13), 
        ClassKeyXch     = (5 << 13),
        TypeRSA         = (2 << 9),
        TypeBlock       = (3 << 9),
        TypeStream      = (4 << 9), 
        TypeDH          = (5 << 9),
 
        NameDES         = 1, 
        NameRC2         = 2,
        Name3DES        = 3, 
        NameAES_128     = 14,
        NameAES_192     = 15,
        NameAES_256     = 16,
        NameAES         = 17, 

        NameRC4         = 1, 
 
        NameMD5         = 3,
        NameSHA         = 4, 

        NameDH_Ephem    = 2,
    }
 
    //From Schannel.h
    [StructLayout(LayoutKind.Sequential)] 
    internal class SslConnectionInfo { 
        public readonly int           Protocol;
        public readonly int           DataCipherAlg; 
        public readonly int           DataKeySize;
        public readonly int           DataHashAlg;
        public readonly int           DataHashKeySize;
        public readonly int           KeyExchangeAlg; 
        public readonly int           KeyExchKeySize;
 
        internal unsafe SslConnectionInfo(byte[] nativeBuffer) { 
            fixed(void* voidPtr = nativeBuffer) {
                IntPtr unmanagedAddress = new IntPtr(voidPtr); 
                Protocol        = Marshal.ReadInt32(unmanagedAddress);
                DataCipherAlg   = Marshal.ReadInt32(unmanagedAddress, 4);
                DataKeySize     = Marshal.ReadInt32(unmanagedAddress, 8);
                DataHashAlg     = Marshal.ReadInt32(unmanagedAddress, 12); 
                DataHashKeySize = Marshal.ReadInt32(unmanagedAddress, 16);
                KeyExchangeAlg  = Marshal.ReadInt32(unmanagedAddress, 20); 
                KeyExchKeySize  = Marshal.ReadInt32(unmanagedAddress, 24); 
            }
        } 
    }

    [StructLayout(LayoutKind.Sequential)]
    internal struct NegotiationInfo { 
        // see SecPkgContext_NegotiationInfoW in 
 
        // [MarshalAs(UnmanagedType.LPStruct)] internal SecurityPackageInfo PackageInfo; 
        internal IntPtr PackageInfo;
        internal uint NegotiationState; 
        internal static readonly int Size = Marshal.SizeOf(typeof(NegotiationInfo));
        internal static readonly int NegotiationStateOffest = (int)Marshal.OffsetOf(typeof(NegotiationInfo), "NegotiationState");
    }
 
    // we keep it simple since we use this only to know if NTLM or
    // Kerberos are used in the context of a Negotiate handshake 
    internal class NegotiationInfoClass { 
        internal const string NTLM      = "NTLM";
        internal const string Kerberos  = "Kerberos"; 
        internal const string WDigest   = "WDigest";
        internal const string Negotiate = "Negotiate";
        internal string AuthenticationPackage;
 
        internal NegotiationInfoClass(SafeHandle safeHandle, int negotiationState) {
            if (safeHandle.IsInvalid) { 
                GlobalLog.Print("NegotiationInfoClass::.ctor() the handle is invalid:" + (safeHandle.DangerousGetHandle()).ToString("x")); 
                return;
            } 
            IntPtr packageInfo = safeHandle.DangerousGetHandle();
            GlobalLog.Print("NegotiationInfoClass::.ctor() packageInfo:" + packageInfo.ToString("x8") + " negotiationState:" + negotiationState.ToString("x8"));

            const int SECPKG_NEGOTIATION_COMPLETE           = 0; 
            const int SECPKG_NEGOTIATION_OPTIMISTIC         = 1;
            // const int SECPKG_NEGOTIATION_IN_PROGRESS     = 2; 
            // const int SECPKG_NEGOTIATION_DIRECT          = 3; 
            // const int SECPKG_NEGOTIATION_TRY_MULTICRED   = 4;
 
            if (negotiationState==SECPKG_NEGOTIATION_COMPLETE || negotiationState==SECPKG_NEGOTIATION_OPTIMISTIC) {
                IntPtr unmanagedString = Marshal.ReadIntPtr(packageInfo, SecurityPackageInfo.NameOffest);
                string name = null;
                if (unmanagedString!=IntPtr.Zero) { 
                    name = ComNetOS.IsWin9x ? Marshal.PtrToStringAnsi(unmanagedString) : Marshal.PtrToStringUni(unmanagedString);
                } 
                GlobalLog.Print("NegotiationInfoClass::.ctor() packageInfo:" + packageInfo.ToString("x8") + " negotiationState:" + negotiationState.ToString("x8") + " name:" + ValidationHelper.ToString(name)); 

                // an optimization for future string comparisons 
                if (string.Compare(name, Kerberos, StringComparison.OrdinalIgnoreCase)==0) {
                    AuthenticationPackage = Kerberos;
                }
                else if (string.Compare(name, NTLM, StringComparison.OrdinalIgnoreCase)==0) { 
                    AuthenticationPackage = NTLM;
                } 
                else if (string.Compare(name, WDigest, StringComparison.OrdinalIgnoreCase)==0) { 
                    AuthenticationPackage = WDigest;
                } 
                else {
                    AuthenticationPackage = name;
                }
            } 
        }
    } 
 
    [StructLayout(LayoutKind.Sequential)]
    internal struct SecurityPackageInfo { 
        // see SecPkgInfoW in 
        internal int Capabilities;
        internal short Version;
        internal short RPCID; 
        internal int MaxToken;
        internal IntPtr Name; 
        internal IntPtr Comment; 

        internal static readonly int Size = Marshal.SizeOf(typeof(SecurityPackageInfo)); 
        internal static readonly int NameOffest = (int)Marshal.OffsetOf(typeof(SecurityPackageInfo), "Name");
    }

    internal class SecurityPackageInfoClass { 
        internal int Capabilities = 0;
        internal short Version = 0; 
        internal short RPCID = 0; 
        internal int MaxToken = 0;
        internal string Name = null; 
        internal string Comment = null;

        /*
         *  This is to support SSL under semi trusted enviornment. 
         *  Note that it is only for SSL with no client cert
         */ 
        internal SecurityPackageInfoClass(SafeHandle safeHandle, int index) { 
            if (safeHandle.IsInvalid) {
                GlobalLog.Print("SecurityPackageInfoClass::.ctor() the pointer is invalid: " + (safeHandle.DangerousGetHandle()).ToString("x")); 
                return;
            }
            IntPtr unmanagedAddress = IntPtrHelper.Add(safeHandle.DangerousGetHandle(), SecurityPackageInfo.Size * index);
            GlobalLog.Print("SecurityPackageInfoClass::.ctor() unmanagedPointer: " + ((long)unmanagedAddress).ToString("x")); 

            Capabilities = Marshal.ReadInt32(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"Capabilities")); 
            Version = Marshal.ReadInt16(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"Version")); 
            RPCID = Marshal.ReadInt16(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"RPCID"));
            MaxToken = Marshal.ReadInt32(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"MaxToken")); 

            IntPtr unmanagedString;

            unmanagedString = Marshal.ReadIntPtr(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"Name")); 
            if (unmanagedString != IntPtr.Zero) {
                if (ComNetOS.IsWin9x) { 
                    Name = Marshal.PtrToStringAnsi(unmanagedString); 
                }
                else { 
                    Name = Marshal.PtrToStringUni(unmanagedString);
                }
                GlobalLog.Print("Name: " + Name);
            } 

            unmanagedString = Marshal.ReadIntPtr(unmanagedAddress, (int)Marshal.OffsetOf(typeof(SecurityPackageInfo),"Comment")); 
            if (unmanagedString != IntPtr.Zero) { 
                if (ComNetOS.IsWin9x) {
                    Comment = Marshal.PtrToStringAnsi(unmanagedString); 
                }
                else {
                    Comment = Marshal.PtrToStringUni(unmanagedString);
                } 
                GlobalLog.Print("Comment: " + Comment);
            } 
 
            GlobalLog.Print("SecurityPackageInfoClass::.ctor(): " + ToString());
        } 

        public override string ToString() {
            return  "Capabilities:" + String.Format(CultureInfo.InvariantCulture, "0x{0:x}", Capabilities)
                + " Version:" + Version.ToString(NumberFormatInfo.InvariantInfo) 
                + " RPCID:" + RPCID.ToString(NumberFormatInfo.InvariantInfo)
                + " MaxToken:" + MaxToken.ToString(NumberFormatInfo.InvariantInfo) 
                + " Name:" + ((Name==null)?"(null)":Name) 
                + " Comment:" + ((Comment==null)?"(null)":Comment
                ); 
        }
    }

    [StructLayout(LayoutKind.Sequential)] 
    internal struct Bindings {
        // see SecPkgContext_Bindings in  
        internal int BindingsLength; 
        internal IntPtr pBindings;
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
                        

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