private static async Task copyHttp2FrameAsync(Stream input, Stream output, Action <byte[], int, int> onCopy,
Http2Settings localSettings, Http2Settings remoteSettings,
Func <SessionEventArgs> sessionFactory, ConcurrentDictionary <int, SessionEventArgs> sessions,
Func <SessionEventArgs, Task> onBeforeRequestResponse,
int bufferSize, Guid connectionId, bool isClient, CancellationToken cancellationToken,
ExceptionHandler exceptionFunc)
{
int headerTableSize = 0;
Decoder decoder = null;
var frameHeader = new Http2FrameHeader();
frameHeader.Buffer = new byte[9];
byte[] buffer = null;
while (true)
{
var frameHeaderBuffer = frameHeader.Buffer;
int read = await forceRead(input, frameHeaderBuffer, 0, 9, cancellationToken);
onCopy(frameHeaderBuffer, 0, read);
if (read != 9)
{
return;
}
int length = (frameHeaderBuffer[0] << 16) + (frameHeaderBuffer[1] << 8) + frameHeaderBuffer[2];
var type = (Http2FrameType)frameHeaderBuffer[3];
var flags = (Http2FrameFlag)frameHeaderBuffer[4];
int streamId = ((frameHeaderBuffer[5] & 0x7f) << 24) + (frameHeaderBuffer[6] << 16) +
(frameHeaderBuffer[7] << 8) + frameHeaderBuffer[8];
frameHeader.Length = length;
frameHeader.Type = type;
frameHeader.Flags = flags;
frameHeader.StreamId = streamId;
if (buffer == null || buffer.Length < localSettings.MaxFrameSize)
{
buffer = new byte[localSettings.MaxFrameSize];
}
read = await forceRead(input, buffer, 0, length, cancellationToken);
onCopy(buffer, 0, read);
if (read != length)
{
return;
}
bool sendPacket = true;
bool endStream = false;
SessionEventArgs args = null;
RequestResponseBase rr = null;
if (type == Http2FrameType.Data || type == Http2FrameType.Headers /* || type == Http2FrameType.PushPromise*/)
{
if (!sessions.TryGetValue(streamId, out args))
{
//if (type == Http2FrameType.Data)
//{
// throw new ProxyHttpException("HTTP Body data received before any header frame.", null, args);
//}
//if (type == Http2FrameType.Headers && !isClient)
//{
// throw new ProxyHttpException("HTTP Response received before any Request header frame.", null, args);
//}
if (type == Http2FrameType.PushPromise && isClient)
{
throw new ProxyHttpException("HTTP Push promise received from the client.", null, args);
}
}
}
//System.Diagnostics.Debug.WriteLine("CONN: " + connectionId + ", CLIENT: " + isClient + ", STREAM: " + streamId + ", TYPE: " + type);
if (type == Http2FrameType.Data && args != null)
{
rr = isClient ? (RequestResponseBase)args.HttpClient.Request : args.HttpClient.Response;
bool padded = (flags & Http2FrameFlag.Padded) != 0;
bool endStreamFlag = (flags & Http2FrameFlag.EndStream) != 0;
if (endStreamFlag)
{
endStream = true;
}
if (rr.Http2IgnoreBodyFrames)
{
sendPacket = false;
}
if (rr.ReadHttp2BodyTaskCompletionSource != null)
{
// Get body method was called in the "before" event handler
var data = rr.Http2BodyData;
int offset = 0;
if (padded)
{
offset++;
length--;
length -= buffer[0];
}
data.Write(buffer, offset, length);
}
}
else if (type == Http2FrameType.Headers /* || type == Http2FrameType.PushPromise*/)
{
bool endHeaders = (flags & Http2FrameFlag.EndHeaders) != 0;
bool padded = (flags & Http2FrameFlag.Padded) != 0;
bool priority = (flags & Http2FrameFlag.Priority) != 0;
bool endStreamFlag = (flags & Http2FrameFlag.EndStream) != 0;
if (endStreamFlag)
{
endStream = true;
}
int offset = 0;
if (padded)
{
offset = 1;
breakpoint();
}
if (type == Http2FrameType.PushPromise)
{
int promisedStreamId = (buffer[offset++] << 24) + (buffer[offset++] << 16) + (buffer[offset++] << 8) + buffer[offset++];
if (!sessions.TryGetValue(streamId, out args))
{
args = sessionFactory();
args.IsPromise = true;
sessions.TryAdd(streamId, args);
sessions.TryAdd(promisedStreamId, args);
}
System.Diagnostics.Debug.WriteLine("PROMISE STREAM: " + streamId + ", " + promisedStreamId +
", CONN: " + connectionId);
rr = args.HttpClient.Request;
if (isClient)
{
// push_promise from client???
breakpoint();
}
}
else
{
if (!sessions.TryGetValue(streamId, out args))
{
args = sessionFactory();
sessions.TryAdd(streamId, args);
}
rr = isClient ? (RequestResponseBase)args.HttpClient.Request : args.HttpClient.Response;
if (priority)
{
var priorityData = ((long)buffer[offset++] << 32) + ((long)buffer[offset++] << 24) +
(buffer[offset++] << 16) + (buffer[offset++] << 8) + buffer[offset++];
rr.Priority = priorityData;
}
}
int dataLength = length - offset;
if (padded)
{
dataLength -= buffer[0];
}
var headerListener = new MyHeaderListener(
(name, value) =>
{
var headers = isClient ? args.HttpClient.Request.Headers : args.HttpClient.Response.Headers;
headers.AddHeader(name, value);
});
try
{
// recreate the decoder when new value is bigger
// should we recreate when smaller, too?
if (decoder == null || headerTableSize < localSettings.HeaderTableSize)
{
headerTableSize = localSettings.HeaderTableSize;
decoder = new Decoder(8192, headerTableSize);
}
decoder.Decode(new BinaryReader(new MemoryStream(buffer, offset, dataLength)),
headerListener);
decoder.EndHeaderBlock();
if (rr is Request request)
{
request.HttpVersion = HttpVersion.Version20;
request.Method = headerListener.Method;
request.OriginalUrl = headerListener.Path;
request.RequestUri = headerListener.GetUri();
}
else
{
var response = (Response)rr;
response.HttpVersion = HttpVersion.Version20;
int.TryParse(headerListener.Status, out int statusCode);
response.StatusCode = statusCode;
}
}
catch (Exception ex)
{
exceptionFunc(new ProxyHttpException("Failed to decode HTTP/2 headers", ex, args));
}
if (!endHeaders)
{
breakpoint();
}
if (endHeaders)
{
var tcs = new TaskCompletionSource <bool>();
rr.ReadHttp2BeforeHandlerTaskCompletionSource = tcs;
var handler = onBeforeRequestResponse(args);
rr.Http2BeforeHandlerTask = handler;
if (handler == await Task.WhenAny(tcs.Task, handler))
{
rr.ReadHttp2BeforeHandlerTaskCompletionSource = null;
tcs.SetResult(true);
await sendHeader(remoteSettings, frameHeader, rr, endStream, output, args.IsPromise);
}
else
{
rr.Http2IgnoreBodyFrames = true;
}
rr.Locked = true;
}
sendPacket = false;
}
else if (type == Http2FrameType.Continuation)
{
// todo: implementing this type is mandatory for multi-part headers
breakpoint();
}
else if (type == Http2FrameType.Settings)
{
if (length % 6 != 0)
{
// https://httpwg.org/specs/rfc7540.html#SETTINGS
// 6.5. SETTINGS
// A SETTINGS frame with a length other than a multiple of 6 octets MUST be treated as a connection error (Section 5.4.1) of type FRAME_SIZE_ERROR
throw new ProxyHttpException("Invalid settings length", null, null);
}
int pos = 0;
while (pos < length)
{
int identifier = (buffer[pos++] << 8) + buffer[pos++];
int value = (buffer[pos++] << 24) + (buffer[pos++] << 16) + (buffer[pos++] << 8) + buffer[pos++];
if (identifier == 1 /*SETTINGS_HEADER_TABLE_SIZE*/)
{
//System.Diagnostics.Debug.WriteLine("HEADER SIZE CONN: " + connectionId + ", CLIENT: " + isClient + ", value: " + value);
remoteSettings.HeaderTableSize = value;
}
else if (identifier == 5 /*SETTINGS_MAX_FRAME_SIZE*/)
{
remoteSettings.MaxFrameSize = value;
}
}
}
if (type == Http2FrameType.RstStream)
{
int errorCode = (buffer[0] << 24) + (buffer[1] << 16) + (buffer[2] << 8) + buffer[3];
if (streamId == 0)
{
// connection error
exceptionFunc(new ProxyHttpException("HTTP/2 connection error. Error code: " + errorCode, null, args));
return;
}
else
{
// stream error
sessions.TryRemove(streamId, out _);
if (errorCode != 8 /*cancel*/)
{
exceptionFunc(new ProxyHttpException("HTTP/2 stream error. Error code: " + errorCode, null, args));
}
}
}
if (endStream && rr.ReadHttp2BodyTaskCompletionSource != null)
{
if (!rr.BodyAvailable)
{
var data = rr.Http2BodyData;
var body = data.ToArray();
if (rr.ContentEncoding != null)
{
using (var ms = new MemoryStream())
{
using (var zip =
DecompressionFactory.Create(rr.ContentEncoding, new MemoryStream(body)))
{
zip.CopyTo(ms);
}
body = ms.ToArray();
}
}
rr.Body = body;
}
rr.IsBodyRead = true;
var tcs = rr.ReadHttp2BodyTaskCompletionSource;
rr.ReadHttp2BodyTaskCompletionSource = null;
if (!tcs.Task.IsCompleted)
{
tcs.SetResult(true);
}
rr.Http2BodyData = null;
if (rr.Http2BeforeHandlerTask != null)
{
await rr.Http2BeforeHandlerTask;
}
if (args.IsPromise)
{
breakpoint();
}
await sendBody(remoteSettings, rr, frameHeader, buffer, output);
}
if (!isClient && endStream)
{
sessions.TryRemove(streamId, out _);
System.Diagnostics.Debug.WriteLine("REMOVED CONN: " + connectionId + ", CLIENT: " + isClient + ", STREAM: " + streamId + ", TYPE: " + type);
}
if (sendPacket)
{
// do not cancel the write operation
var buf = frameHeader.CopyToBuffer();
await output.WriteAsync(buf, 0, buf.Length /*, cancellationToken*/);
await output.WriteAsync(buffer, 0, length /*, cancellationToken*/);
}
if (cancellationToken.IsCancellationRequested)
{
return;
}
/*using (var fs = new System.IO.FileStream($@"c:\temp\{connectionId}.{streamId}.dat", FileMode.Append))
* {
* fs.Write(headerBuffer, 0, headerBuffer.Length);
* fs.Write(buffer, 0, length);
* }*/
}
}
public PrefaceUserEventHttp2ConnectionHandler(CountdownEvent latch, IHttp2ConnectionDecoder decoder, IHttp2ConnectionEncoder encoder, Http2Settings initialSettings)
: base(decoder, encoder, initialSettings)
{
_latch = latch;
}
private static async Task sendHeader(Http2Settings settings, Http2FrameHeader frameHeader, RequestResponseBase rr, bool endStream, Stream output, bool pushPromise)
{
var encoder = new Encoder(settings.HeaderTableSize);
var ms = new MemoryStream();
var writer = new BinaryWriter(ms);
if (rr.Priority.HasValue)
{
long p = rr.Priority.Value;
writer.Write((byte)((p >> 32) & 0xff));
writer.Write((byte)((p >> 24) & 0xff));
writer.Write((byte)((p >> 16) & 0xff));
writer.Write((byte)((p >> 8) & 0xff));
writer.Write((byte)(p & 0xff));
}
if (rr is Request request)
{
encoder.EncodeHeader(writer, ":method", request.Method);
encoder.EncodeHeader(writer, ":authority", request.RequestUri.Host);
encoder.EncodeHeader(writer, ":scheme", request.RequestUri.Scheme);
encoder.EncodeHeader(writer, ":path", request.RequestUriString, false,
HpackUtil.IndexType.None, false);
}
else
{
var response = (Response)rr;
encoder.EncodeHeader(writer, ":status", response.StatusCode.ToString());
}
foreach (var header in rr.Headers)
{
encoder.EncodeHeader(writer, header.Name.ToLower(), header.Value);
}
var data = ms.ToArray();
int newLength = data.Length;
frameHeader.Length = newLength;
frameHeader.Type = pushPromise ? Http2FrameType.PushPromise : Http2FrameType.Headers;
var flags = Http2FrameFlag.EndHeaders;
if (endStream)
{
flags |= Http2FrameFlag.EndStream;
}
if (rr.Priority.HasValue)
{
flags |= Http2FrameFlag.Priority;
}
frameHeader.Flags = flags;
// clear the padding flag
//headerBuffer[4] = (byte)(flags & ~((int)Http2FrameFlag.Padded));
// send the header
var buf = frameHeader.CopyToBuffer();
await output.WriteAsync(buf, 0, buf.Length /*, cancellationToken*/);
await output.WriteAsync(data, 0, data.Length /*, cancellationToken*/);
}
