/// <summary>
/// Fills the buffer with the header value and returns the length, or returns 0 if the header isn't found.
/// </summary>
private unsafe static int GetResponseHeader(SafeWinHttpHandle requestHandle, uint infoLevel, char[] buffer)
{
Debug.Assert(buffer != null, "buffer must not be null.");
Debug.Assert(buffer.Length > 0, "buffer must not be empty.");
int bufferLength = buffer.Length;
uint index = 0;
fixed(char *pBuffer = buffer)
{
if (!QueryHeaders(requestHandle, infoLevel, pBuffer, ref bufferLength, ref index))
{
int lastError = Marshal.GetLastWin32Error();
if (lastError == Interop.WinHttp.ERROR_WINHTTP_HEADER_NOT_FOUND)
{
return(0);
}
Debug.Assert(lastError != Interop.WinHttp.ERROR_INSUFFICIENT_BUFFER, "buffer must be of sufficient size.");
throw WinHttpException.CreateExceptionUsingError(lastError);
}
}
return(bufferLength);
}
public unsafe static bool GetResponseHeader(
SafeWinHttpHandle requestHandle,
uint infoLevel,
ref char[] buffer,
ref uint index,
out string headerValue)
{
const int StackLimit = 128;
Debug.Assert(buffer == null || (buffer != null && buffer.Length > StackLimit));
int bufferLength;
uint originalIndex = index;
if (buffer == null)
{
bufferLength = StackLimit;
char *pBuffer = stackalloc char[bufferLength];
if (QueryHeaders(requestHandle, infoLevel, pBuffer, ref bufferLength, ref index))
{
headerValue = new string(pBuffer, 0, bufferLength);
return(true);
}
}
else
{
bufferLength = buffer.Length;
fixed(char *pBuffer = buffer)
{
if (QueryHeaders(requestHandle, infoLevel, pBuffer, ref bufferLength, ref index))
{
headerValue = new string(pBuffer, 0, bufferLength);
return(true);
}
}
}
int lastError = Marshal.GetLastWin32Error();
if (lastError == Interop.WinHttp.ERROR_WINHTTP_HEADER_NOT_FOUND)
{
headerValue = null;
return(false);
}
if (lastError == Interop.WinHttp.ERROR_INSUFFICIENT_BUFFER)
{
// WinHttpQueryHeaders may advance the index even when it fails due to insufficient buffer,
// so we set the index back to its original value so we can retry retrieving the same
// index again with a larger buffer.
index = originalIndex;
buffer = new char[bufferLength];
return(GetResponseHeader(requestHandle, infoLevel, ref buffer, ref index, out headerValue));
}
throw WinHttpException.CreateExceptionUsingError(lastError);
}
/// <summary>
/// Returns the size of the char array buffer.
/// </summary>
private unsafe static int GetResponseHeaderCharBufferLength(SafeWinHttpHandle requestHandle, uint infoLevel)
{
char *buffer = null;
int bufferLength = 0;
uint index = 0;
if (!QueryHeaders(requestHandle, infoLevel, buffer, ref bufferLength, ref index))
{
int lastError = Marshal.GetLastWin32Error();
Debug.Assert(lastError != Interop.WinHttp.ERROR_WINHTTP_HEADER_NOT_FOUND);
if (lastError != Interop.WinHttp.ERROR_INSUFFICIENT_BUFFER)
{
throw WinHttpException.CreateExceptionUsingError(lastError);
}
}
return(bufferLength);
}
public static void ResetCookieRequestHeaders(WinHttpRequestState state, Uri redirectUri)
{
SafeWinHttpHandle requestHandle = state.RequestHandle;
Debug.Assert(state.Handler.CookieUsePolicy == CookieUsePolicy.UseSpecifiedCookieContainer);
// Clear cookies.
if (!Interop.WinHttp.WinHttpAddRequestHeaders(
requestHandle,
CookieHeaderNameWithColon,
(uint)CookieHeaderNameWithColon.Length,
Interop.WinHttp.WINHTTP_ADDREQ_FLAG_REPLACE))
{
int lastError = Marshal.GetLastWin32Error();
if (lastError != Interop.WinHttp.ERROR_WINHTTP_HEADER_NOT_FOUND)
{
throw WinHttpException.CreateExceptionUsingError(lastError);
}
}
// Re-add cookies. The GetCookieHeader() method will return the correct set of
// cookies based on the redirectUri.
string cookieHeader = GetCookieHeader(redirectUri, state.Handler.CookieContainer);
if (!string.IsNullOrEmpty(cookieHeader))
{
if (!Interop.WinHttp.WinHttpAddRequestHeaders(
requestHandle,
cookieHeader,
(uint)cookieHeader.Length,
Interop.WinHttp.WINHTTP_ADDREQ_FLAG_ADD))
{
WinHttpException.ThrowExceptionUsingLastError();
}
}
}
private static void OnRequestError(WinHttpRequestState state, Interop.WinHttp.WINHTTP_ASYNC_RESULT asyncResult)
{
WinHttpTraceHelper.TraceAsyncError("OnRequestError", asyncResult);
Debug.Assert(state != null, "OnRequestError: state is null");
Exception innerException = WinHttpException.CreateExceptionUsingError(unchecked ((int)asyncResult.dwError));
switch (unchecked ((uint)asyncResult.dwResult.ToInt32()))
{
case Interop.WinHttp.API_SEND_REQUEST:
state.TcsSendRequest.TrySetException(innerException);
break;
case Interop.WinHttp.API_RECEIVE_RESPONSE:
if (asyncResult.dwError == Interop.WinHttp.ERROR_WINHTTP_RESEND_REQUEST)
{
state.RetryRequest = true;
state.TcsReceiveResponseHeaders.TrySetResult(false);
}
else if (asyncResult.dwError == Interop.WinHttp.ERROR_WINHTTP_CLIENT_AUTH_CERT_NEEDED)
{
// WinHttp will automatically drop any client SSL certificates that we
// have pre-set into the request handle including the NULL certificate
// (which means we have no certs to send). For security reasons, we don't
// allow the certificate to be re-applied. But we need to tell WinHttp
// explicitly that we don't have any certificate to send.
Debug.Assert(state.RequestHandle != null, "OnRequestError: state.RequestHandle is null");
WinHttpHandler.SetNoClientCertificate(state.RequestHandle);
state.RetryRequest = true;
state.TcsReceiveResponseHeaders.TrySetResult(false);
}
else if (asyncResult.dwError == Interop.WinHttp.ERROR_WINHTTP_OPERATION_CANCELLED)
{
state.TcsReceiveResponseHeaders.TrySetCanceled(state.CancellationToken);
}
else
{
state.TcsReceiveResponseHeaders.TrySetException(innerException);
}
break;
case Interop.WinHttp.API_QUERY_DATA_AVAILABLE:
if (asyncResult.dwError == Interop.WinHttp.ERROR_WINHTTP_OPERATION_CANCELLED)
{
// TODO: Issue #2165. We need to pass in the cancellation token from the
// user's ReadAsync() call into the TrySetCanceled().
Debug.WriteLine("RequestCallback: QUERY_DATA_AVAILABLE - ERROR_WINHTTP_OPERATION_CANCELLED");
state.TcsQueryDataAvailable.TrySetCanceled();
}
else
{
state.TcsQueryDataAvailable.TrySetException(
new IOException("net_http_io_read", innerException));
}
break;
case Interop.WinHttp.API_READ_DATA:
state.DisposeCtrReadFromResponseStream();
if (asyncResult.dwError == Interop.WinHttp.ERROR_WINHTTP_OPERATION_CANCELLED)
{
// TODO: Issue #2165. We need to pass in the cancellation token from the
// user's ReadAsync() call into the TrySetCanceled().
Debug.WriteLine("RequestCallback: API_READ_DATA - ERROR_WINHTTP_OPERATION_CANCELLED");
state.TcsReadFromResponseStream.TrySetCanceled();
}
else
{
state.TcsReadFromResponseStream.TrySetException(
new IOException("net_http_io_read", innerException));
}
break;
case Interop.WinHttp.API_WRITE_DATA:
if (asyncResult.dwError == Interop.WinHttp.ERROR_WINHTTP_OPERATION_CANCELLED)
{
// TODO: Issue #2165. We need to pass in the cancellation token from the
// user's WriteAsync() call into the TrySetCanceled().
Debug.WriteLine("RequestCallback: API_WRITE_DATA - ERROR_WINHTTP_OPERATION_CANCELLED");
state.TcsInternalWriteDataToRequestStream.TrySetCanceled();
}
else
{
state.TcsInternalWriteDataToRequestStream.TrySetException(
new IOException("net_http_io_write", innerException));
}
break;
default:
Debug.Fail(
"OnRequestError: Result (" + asyncResult.dwResult + ") is not expected.",
"Error code: " + asyncResult.dwError + " (" + innerException.Message + ")");
break;
}
}
private static void OnRequestSendingRequest(WinHttpRequestState state)
{
Debug.Assert(state != null, "OnRequestSendingRequest: state is null");
Debug.Assert(state.RequestHandle != null, "OnRequestSendingRequest: state.RequestHandle is null");
if (state.RequestMessage.RequestUri.Scheme != UriScheme.Https)
{
// Not SSL/TLS.
return;
}
// Grab the channel binding token (CBT) information from the request handle and put it into
// the TransportContext object.
state.TransportContext.SetChannelBinding(state.RequestHandle);
if (state.ServerCertificateValidationCallback != null)
{
IntPtr certHandle = IntPtr.Zero;
uint certHandleSize = (uint)IntPtr.Size;
if (!Interop.WinHttp.WinHttpQueryOption(
state.RequestHandle,
Interop.WinHttp.WINHTTP_OPTION_SERVER_CERT_CONTEXT,
ref certHandle,
ref certHandleSize))
{
int lastError = Marshal.GetLastWin32Error();
throw WinHttpException.CreateExceptionUsingError(lastError);
}
// Create a managed wrapper around the certificate handle. Since this results in duplicating
// the handle, we will close the original handle after creating the wrapper.
var serverCertificate = new X509Certificate2(certHandle);
Interop.Crypt32.CertFreeCertificateContext(certHandle);
X509Chain chain = null;
SslPolicyErrors sslPolicyErrors;
try
{
WinHttpCertificateHelper.BuildChain(
serverCertificate,
state.RequestMessage.RequestUri.Host,
state.CheckCertificateRevocationList,
out chain,
out sslPolicyErrors);
bool result = state.ServerCertificateValidationCallback(
state.RequestMessage,
serverCertificate,
chain,
sslPolicyErrors);
if (!result)
{
throw WinHttpException.CreateExceptionUsingError(
(int)Interop.WinHttp.ERROR_WINHTTP_SECURE_FAILURE);
}
}
finally
{
if (chain != null)
{
chain.Dispose();
}
serverCertificate.Dispose();
}
}
}