static byte[] GssWrap(
SafeGssContextHandle context,
bool encrypt,
byte[] buffer,
int offset,
int count)
{
Debug.Assert((buffer != null) && (buffer.Length > 0), "Invalid input buffer passed to Encrypt");
Debug.Assert((offset >= 0) && (offset < buffer.Length), "Invalid input offset passed to Encrypt");
Debug.Assert((count >= 0) && (count <= (buffer.Length - offset)), "Invalid input count passed to Encrypt");
Interop.NetSecurityNative.GssBuffer encryptedBuffer = default(Interop.NetSecurityNative.GssBuffer);
try
{
Interop.NetSecurityNative.Status minorStatus;
Interop.NetSecurityNative.Status status = Interop.NetSecurityNative.WrapBuffer(out minorStatus, context, encrypt, buffer, offset, count, ref encryptedBuffer);
if (status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
return(encryptedBuffer.ToByteArray());
}
finally
{
encryptedBuffer.Dispose();
}
}
private static int GssUnwrap(
SafeGssContextHandle?context,
byte[] buffer,
int offset,
int count)
{
Debug.Assert((buffer != null) && (buffer.Length > 0), "Invalid input buffer passed to Decrypt");
Debug.Assert((offset >= 0) && (offset <= buffer.Length), "Invalid input offset passed to Decrypt");
Debug.Assert((count >= 0) && (count <= (buffer.Length - offset)), "Invalid input count passed to Decrypt");
Interop.NetSecurityNative.GssBuffer decryptedBuffer = default(Interop.NetSecurityNative.GssBuffer);
try
{
Interop.NetSecurityNative.Status minorStatus;
Interop.NetSecurityNative.Status status = Interop.NetSecurityNative.UnwrapBuffer(out minorStatus, context, buffer, offset, count, ref decryptedBuffer);
if (status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
return(decryptedBuffer.Copy(buffer, offset));
}
finally
{
decryptedBuffer.Dispose();
}
}
internal static int Encrypt(
SafeDeleteContext securityContext,
ReadOnlySpan <byte> buffer,
bool isConfidential,
bool isNtlm,
[NotNull] ref byte[]?output)
{
SafeGssContextHandle gssContext = ((SafeDeleteNegoContext)securityContext).GssContext !;
int resultSize;
if (isNtlm && !isConfidential)
{
Interop.NetSecurityNative.GssBuffer micBuffer = default;
try
{
Interop.NetSecurityNative.Status minorStatus;
Interop.NetSecurityNative.Status status = Interop.NetSecurityNative.GetMic(
out minorStatus,
gssContext,
buffer,
ref micBuffer);
if (status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
resultSize = micBuffer.Span.Length + buffer.Length;
if (output == null || output.Length < resultSize + 4)
{
output = new byte[resultSize + 4];
}
micBuffer.Span.CopyTo(output.AsSpan(4));
buffer.CopyTo(output.AsSpan(micBuffer.Span.Length + 4));
BinaryPrimitives.WriteInt32LittleEndian(output, resultSize);
return(resultSize + 4);
}
finally
{
micBuffer.Dispose();
}
}
byte[] tempOutput = GssWrap(gssContext, ref 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);
resultSize = tempOutput.Length;
BinaryPrimitives.WriteInt32LittleEndian(output, resultSize);
return(resultSize + 4);
}
private static bool GssInitSecurityContext(
ref SafeGssContextHandle context,
SafeGssCredHandle credential,
bool isNtlm,
SafeGssNameHandle targetName,
Interop.NetSecurityNative.GssFlags inFlags,
byte[] buffer,
out byte[] outputBuffer,
out uint outFlags,
out int isNtlmUsed)
{
outputBuffer = null;
outFlags = 0;
// EstablishSecurityContext is called multiple times in a session.
// In each call, we need to pass the context handle from the previous call.
// For the first call, the context handle will be null.
if (context == null)
{
context = new SafeGssContextHandle();
}
Interop.NetSecurityNative.GssBuffer token = default;
Interop.NetSecurityNative.Status status;
try
{
Interop.NetSecurityNative.Status minorStatus;
status = Interop.NetSecurityNative.InitSecContext(out minorStatus,
credential,
ref context,
isNtlm,
targetName,
(uint)inFlags,
buffer,
(buffer == null) ? 0 : buffer.Length,
ref token,
out outFlags,
out isNtlmUsed);
if ((status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE) && (status != Interop.NetSecurityNative.Status.GSS_S_CONTINUE_NEEDED))
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
outputBuffer = token.ToByteArray();
}
finally
{
token.Dispose();
}
return(status == Interop.NetSecurityNative.Status.GSS_S_COMPLETE);
}
private static bool GssAcceptSecurityContext(
ref SafeGssContextHandle?context,
SafeGssCredHandle credential,
byte[]?buffer,
out byte[] outputBuffer,
out uint outFlags,
out bool isNtlmUsed)
{
Debug.Assert(credential != null);
bool newContext = false;
if (context == null)
{
newContext = true;
context = new SafeGssContextHandle();
}
Interop.NetSecurityNative.GssBuffer token = default(Interop.NetSecurityNative.GssBuffer);
Interop.NetSecurityNative.Status status;
try
{
Interop.NetSecurityNative.Status minorStatus;
status = Interop.NetSecurityNative.AcceptSecContext(out minorStatus,
credential,
ref context,
buffer,
buffer?.Length ?? 0,
ref token,
out outFlags,
out isNtlmUsed);
if ((status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE) &&
(status != Interop.NetSecurityNative.Status.GSS_S_CONTINUE_NEEDED))
{
if (newContext)
{
context.Dispose();
context = null;
}
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
outputBuffer = token.ToByteArray();
}
finally
{
token.Dispose();
}
return(status == Interop.NetSecurityNative.Status.GSS_S_COMPLETE);
}
private static bool EstablishSecurityContext(
ref SafeGssContextHandle context,
byte[] buffer,
out byte[] outputBuffer)
{
outputBuffer = null;
// EstablishSecurityContext is called multiple times in a session.
// In each call, we need to pass the context handle from the previous call.
// For the first call, the context handle will be null.
if (context == null)
{
context = new SafeGssContextHandle();
}
Interop.NetSecurityNative.GssBuffer token = default(Interop.NetSecurityNative.GssBuffer);
Interop.NetSecurityNative.Status status;
try
{
Interop.NetSecurityNative.Status minorStatus;
status = Interop.NetSecurityNative.AcceptSecContext(out minorStatus,
ref context,
buffer,
(buffer == null) ? 0 : buffer.Length,
ref token);
if ((status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE) && (status != Interop.NetSecurityNative.Status.GSS_S_CONTINUE_NEEDED))
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
outputBuffer = token.ToByteArray();
}
finally
{
token.Dispose();
}
return(status == Interop.NetSecurityNative.Status.GSS_S_COMPLETE);
}
private static byte[] GssWrap(
SafeGssContextHandle?context,
bool encrypt,
ReadOnlySpan <byte> buffer)
{
Interop.NetSecurityNative.GssBuffer encryptedBuffer = default;
try
{
Interop.NetSecurityNative.Status minorStatus;
Interop.NetSecurityNative.Status status = Interop.NetSecurityNative.WrapBuffer(out minorStatus, context, encrypt, buffer, ref encryptedBuffer);
if (status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
return(encryptedBuffer.ToByteArray());
}
finally
{
encryptedBuffer.Dispose();
}
}
private static byte[] WrapMessage(SafeGssContextHandle context, byte[] message)
{
Interop.NetSecurityNative.GssBuffer wrapped = default(Interop.NetSecurityNative.GssBuffer);
Interop.NetSecurityNative.Status status;
try
{
Interop.NetSecurityNative.Status minorStatus;
status = Interop.NetSecurityNative.WrapBuffer(out minorStatus,
context, false, message, 0, message.Length, ref wrapped);
if (status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
return(wrapped.ToByteArray());
}
finally
{
wrapped.Dispose();
}
}
private static int GssUnwrap(
SafeGssContextHandle context,
out bool encrypt,
Span <byte> buffer)
{
Interop.NetSecurityNative.GssBuffer decryptedBuffer = default(Interop.NetSecurityNative.GssBuffer);
try
{
Interop.NetSecurityNative.Status minorStatus;
Interop.NetSecurityNative.Status status = Interop.NetSecurityNative.UnwrapBuffer(out minorStatus, context, out encrypt, buffer, ref decryptedBuffer);
if (status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
decryptedBuffer.Span.CopyTo(buffer);
return(decryptedBuffer.Span.Length);
}
finally
{
decryptedBuffer.Dispose();
}
}
private static string GssGetUser(
ref SafeGssContextHandle?context)
{
Interop.NetSecurityNative.GssBuffer token = default(Interop.NetSecurityNative.GssBuffer);
try
{
Interop.NetSecurityNative.Status status
= Interop.NetSecurityNative.GetUser(out var minorStatus,
context,
ref token);
if (status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
ReadOnlySpan <byte> tokenBytes = token.Span;
int length = tokenBytes.Length;
if (length > 0 && tokenBytes[length - 1] == '\0')
{
// Some GSS-API providers (gss-ntlmssp) include the terminating null with strings, so skip that.
tokenBytes = tokenBytes.Slice(0, length - 1);
}
#if NETSTANDARD2_0
return(Encoding.UTF8.GetString(tokenBytes.ToArray(), 0, tokenBytes.Length));
#else
return(Encoding.UTF8.GetString(tokenBytes));
#endif
}
finally
{
token.Dispose();
}
}
private static string GssGetUser(
ref SafeGssContextHandle context)
{
Interop.NetSecurityNative.GssBuffer token = default(Interop.NetSecurityNative.GssBuffer);
try
{
Interop.NetSecurityNative.Status status
= Interop.NetSecurityNative.GetUser(out var minorStatus,
context,
ref token);
if (status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE)
{
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
return(Encoding.UTF8.GetString(token.ToByteArray()));
}
finally
{
token.Dispose();
}
}
private static bool GssInitSecurityContext(
ref SafeGssContextHandle?context,
SafeGssCredHandle credential,
bool isNtlm,
ChannelBinding?channelBinding,
SafeGssNameHandle?targetName,
Interop.NetSecurityNative.GssFlags inFlags,
byte[]?buffer,
out byte[]?outputBuffer,
out uint outFlags,
out bool isNtlmUsed)
{
outputBuffer = null;
outFlags = 0;
// EstablishSecurityContext is called multiple times in a session.
// In each call, we need to pass the context handle from the previous call.
// For the first call, the context handle will be null.
bool newContext = false;
if (context == null)
{
newContext = true;
context = new SafeGssContextHandle();
}
Interop.NetSecurityNative.GssBuffer token = default(Interop.NetSecurityNative.GssBuffer);
Interop.NetSecurityNative.Status status;
try
{
Interop.NetSecurityNative.Status minorStatus;
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,
ref context,
isNtlm,
cbtAppData,
cbtAppDataSize,
targetName,
(uint)inFlags,
buffer,
(buffer == null) ? 0 : buffer.Length,
ref token,
out outFlags,
out isNtlmUsed);
}
else
{
status = Interop.NetSecurityNative.InitSecContext(out minorStatus,
credential,
ref context,
isNtlm,
targetName,
(uint)inFlags,
buffer,
(buffer == null) ? 0 : buffer.Length,
ref token,
out outFlags,
out isNtlmUsed);
}
if ((status != Interop.NetSecurityNative.Status.GSS_S_COMPLETE) &&
(status != Interop.NetSecurityNative.Status.GSS_S_CONTINUE_NEEDED))
{
if (newContext)
{
context.Dispose();
context = null;
}
throw new Interop.NetSecurityNative.GssApiException(status, minorStatus);
}
outputBuffer = token.ToByteArray();
}
finally
{
token.Dispose();
}
return(status == Interop.NetSecurityNative.Status.GSS_S_COMPLETE);
}
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);
}
}
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);
}
}
