text: /**
   * FreeRDP: A Remote Desktop Protocol Implementation
   * Dynamic Virtual Channel
   *
   * Copyright 2010-2011 Vic Lee
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #ifdef HAVE_CONFIG_H
  #include "config.h"
  #endif
  
  #include <winpr/crt.h>
  #include <winpr/stream.h>
  
  #include <freerdp/constants.h>
  
  #include "dvcman.h"
  #include "drdynvc_types.h"
  #include "drdynvc_main.h"
  
  static int drdynvc_write_variable_uint(wStream* s, UINT32 val)
  {
  	int cb;
  
  	if (val <= 0xFF)
  	{
  		cb = 0;
  		Stream_Write_UINT8(s, val);
  	}
  	else if (val <= 0xFFFF)
  	{
  		cb = 1;
  		Stream_Write_UINT16(s, val);
  	}
  	else
  	{
  		cb = 2;
  		Stream_Write_UINT32(s, val);
  	}
  
  	return cb;
  }
  
  int drdynvc_send(drdynvcPlugin* drdynvc, wStream* s)
  {
  	UINT32 status = 0;
  
  	if (!drdynvc)
  	{
  		status = CHANNEL_RC_BAD_INIT_HANDLE;
  	}
  	else
  	{
  		status = drdynvc->channelEntryPoints.pVirtualChannelWrite(drdynvc->OpenHandle,
  			Stream_Buffer(s), (UINT32) Stream_GetPosition(s), s);
  	}
  
  	if (status != CHANNEL_RC_OK)
  	{
  		Stream_Free(s, TRUE);
  		WLog_ERR(TAG,  "drdynvc_send: VirtualChannelWrite failed %d", status);
  	}
  
  	return status;
  }
  
  int drdynvc_write_data(drdynvcPlugin* drdynvc, UINT32 ChannelId, BYTE* data, UINT32 dataSize)
  {
  	wStream* data_out;
  	UINT32 pos = 0;
  	UINT32 cbChId;
  	UINT32 cbLen;
  	UINT32 chunkLength;
  	int status;
  
  	DEBUG_DVC("ChannelId=%d size=%d", ChannelId, dataSize);
  
  	if (drdynvc->channel_error != CHANNEL_RC_OK)
  		return 1;
  
  	data_out = Stream_New(NULL, CHANNEL_CHUNK_LENGTH);
  	Stream_SetPosition(data_out, 1);
  	cbChId = drdynvc_write_variable_uint(data_out, ChannelId);
  
  	if (dataSize == 0)
  	{
  		pos = Stream_GetPosition(data_out);
  		Stream_SetPosition(data_out, 0);
  		Stream_Write_UINT8(data_out, 0x40 | cbChId);
  		Stream_SetPosition(data_out, pos);
  
  		status = drdynvc_send(drdynvc, data_out);
  	}
  	else if (dataSize <= CHANNEL_CHUNK_LENGTH - pos)
  	{
  		pos = Stream_GetPosition(data_out);
  		Stream_SetPosition(data_out, 0);
  		Stream_Write_UINT8(data_out, 0x30 | cbChId);
  		Stream_SetPosition(data_out, pos);
  		Stream_Write(data_out, data, dataSize);
  
  		status = drdynvc_send(drdynvc, data_out);
  	}
  	else
  	{
  		/* Fragment the data */
  		cbLen = drdynvc_write_variable_uint(data_out, dataSize);
  		pos = Stream_GetPosition(data_out);
  		Stream_SetPosition(data_out, 0);
  		Stream_Write_UINT8(data_out, 0x20 | cbChId | (cbLen << 2));
  		Stream_SetPosition(data_out, pos);
  
  		chunkLength = CHANNEL_CHUNK_LENGTH - pos;
  
  		Stream_Write(data_out, data, chunkLength);
  
  		data += chunkLength;
  		dataSize -= chunkLength;
  
  		status = drdynvc_send(drdynvc, data_out);
  
  		while (status == CHANNEL_RC_OK && dataSize > 0)
  		{
  			data_out = Stream_New(NULL, CHANNEL_CHUNK_LENGTH);
  			Stream_SetPosition(data_out, 1);
  			cbChId = drdynvc_write_variable_uint(data_out, ChannelId);
  
  			pos = Stream_GetPosition(data_out);
  			Stream_SetPosition(data_out, 0);
  			Stream_Write_UINT8(data_out, 0x30 | cbChId);
  			Stream_SetPosition(data_out, pos);
  
  			chunkLength = dataSize;
  
  			if (chunkLength > CHANNEL_CHUNK_LENGTH - pos)
  				chunkLength = CHANNEL_CHUNK_LENGTH - pos;
  
  			Stream_Write(data_out, data, chunkLength);
  
  			data += chunkLength;
  			dataSize -= chunkLength;
  
  			status = drdynvc_send(drdynvc, data_out);
  		}
  	}
  
  	if (status != CHANNEL_RC_OK)
  	{
  		drdynvc->channel_error = status;
  		WLog_ERR(TAG, "VirtualChannelWrite failed %d", status);
  		return 1;
  	}
  
  	return 0;
  }
  
  static int drdynvc_send_capability_response(drdynvcPlugin* drdynvc)
  {
  	int status;
  	wStream* s;
  
  	s = Stream_New(NULL, 4);
  	Stream_Write_UINT16(s, 0x0050); /* Cmd+Sp+cbChId+Pad. Note: MSTSC sends 0x005c */
  	Stream_Write_UINT16(s, drdynvc->version);
  
  	status = drdynvc_send(drdynvc, s);
  
  	if (status != CHANNEL_RC_OK)
  	{
  		WLog_ERR(TAG, "VirtualChannelWrite failed %d", status);
  		return 1;
  	}
  
  	return status;
  }
  
  static int drdynvc_process_capability_request(drdynvcPlugin* drdynvc, int Sp, int cbChId, wStream* s)
  {
  	int status;
  
  	DEBUG_DVC("Sp=%d cbChId=%d", Sp, cbChId);
  
  	Stream_Seek(s, 1); /* pad */
  	Stream_Read_UINT16(s, drdynvc->version);
  
  	/* RDP8 servers offer version 3, though Microsoft forgot to document it
  	 * in their early documents.  It behaves the same as version 2.
  	 */
  	if ((drdynvc->version == 2) || (drdynvc->version == 3))
  	{
  		Stream_Read_UINT16(s, drdynvc->PriorityCharge0);
  		Stream_Read_UINT16(s, drdynvc->PriorityCharge1);
  		Stream_Read_UINT16(s, drdynvc->PriorityCharge2);
  		Stream_Read_UINT16(s, drdynvc->PriorityCharge3);
  	}
  
  	status = drdynvc_send_capability_response(drdynvc);
  
  	drdynvc->channel_error = status;
  
  	drdynvc->state = DRDYNVC_STATE_READY;
  
  	return 0;
  }
  
  static UINT32 drdynvc_read_variable_uint(wStream* s, int cbLen)
  {
  	UINT32 val;
  
  	switch (cbLen)
  	{
  		case 0:
  			Stream_Read_UINT8(s, val);
  			break;
  
  		case 1:
  			Stream_Read_UINT16(s, val);
  			break;
  
  		default:
  			Stream_Read_UINT32(s, val);
  			break;
  	}
  
  	return val;
  }
  
  static int drdynvc_process_create_request(drdynvcPlugin* drdynvc, int Sp, int cbChId, wStream* s)
  {
  	int pos;
  	int status;
  	UINT32 ChannelId;
  	wStream* data_out;
  	int channel_status;
  
  	if (drdynvc->state == DRDYNVC_STATE_CAPABILITIES)
  	{
  		/**
  		 * For some reason the server does not always send the
  		 * capabilities pdu as it should. When this happens,
  		 * send a capabilities response.
  		 */
  
  		drdynvc->version = 3;
  		drdynvc_send_capability_response(drdynvc);
  		drdynvc->state = DRDYNVC_STATE_READY;
  	}
  
  	ChannelId = drdynvc_read_variable_uint(s, cbChId);
  	pos = Stream_GetPosition(s);
  	DEBUG_DVC("ChannelId=%d ChannelName=%s", ChannelId, Stream_Pointer(s));
  
  	channel_status = dvcman_create_channel(drdynvc->channel_mgr, ChannelId, (char*) Stream_Pointer(s));
  
  	data_out = Stream_New(NULL, pos + 4);
  	Stream_Write_UINT8(data_out, 0x10 | cbChId);
  	Stream_SetPosition(s, 1);
  	Stream_Copy(data_out, s, pos - 1);
  	
  	if (channel_status == 0)
  	{
  		DEBUG_DVC("channel created");
  		Stream_Write_UINT32(data_out, 0);
  	}
  	else
  	{
  		DEBUG_DVC("no listener");
  		Stream_Write_UINT32(data_out, (UINT32)(-1));
  	}
  
  	status = drdynvc_send(drdynvc, data_out);
  
  	if (status != CHANNEL_RC_OK)
  	{
  		WLog_ERR(TAG, "VirtualChannelWrite failed %d", status);
  		return 1;
  	}
  
  	if (channel_status == 0)
  	{
  		dvcman_open_channel(drdynvc->channel_mgr, ChannelId);
  	}
  
  	return 0;
  }
  
  static int drdynvc_process_data_first(drdynvcPlugin* drdynvc, int Sp, int cbChId, wStream* s)
  {
  	int status;
  	UINT32 Length;
  	UINT32 ChannelId;
  
  	ChannelId = drdynvc_read_variable_uint(s, cbChId);
  	Length = drdynvc_read_variable_uint(s, Sp);
  	DEBUG_DVC("ChannelId=%d Length=%d", ChannelId, Length);
  
  	status = dvcman_receive_channel_data_first(drdynvc->channel_mgr, ChannelId, Length);
  
  	if (status)
  		return status;
  
  	return dvcman_receive_channel_data(drdynvc->channel_mgr, ChannelId, s);
  }
  
  static int drdynvc_process_data(drdynvcPlugin* drdynvc, int Sp, int cbChId, wStream* s)
  {
  	UINT32 ChannelId;
  
  	ChannelId = drdynvc_read_variable_uint(s, cbChId);
  	DEBUG_DVC("ChannelId=%d", ChannelId);
  
  	return dvcman_receive_channel_data(drdynvc->channel_mgr, ChannelId, s);
  }
  
  static int drdynvc_process_close_request(drdynvcPlugin* drdynvc, int Sp, int cbChId, wStream* s)
  {
  	int value;
  	int error;
  	UINT32 ChannelId;
  	wStream* data_out;
  
  	ChannelId = drdynvc_read_variable_uint(s, cbChId);
  	DEBUG_DVC("ChannelId=%d", ChannelId);
  	dvcman_close_channel(drdynvc->channel_mgr, ChannelId);
  	
  	data_out = Stream_New(NULL, 4);
  	value = (CLOSE_REQUEST_PDU << 4) | (cbChId & 0x03);
  
  	Stream_Write_UINT8(data_out, value);
  	drdynvc_write_variable_uint(data_out, ChannelId);
  
  	error = drdynvc_send(drdynvc, data_out);
  	
  	if (error != CHANNEL_RC_OK)
  	{
  		WLog_ERR(TAG, "VirtualChannelWrite failed %d", error);
  		return 1;
  	}
  	
  	drdynvc->channel_error = error;
  
  	return 0;
  }
  
  static void drdynvc_order_recv(drdynvcPlugin* drdynvc, wStream* s)
  {
  	int value;
  	int Cmd;
  	int Sp;
  	int cbChId;
  
  	Stream_Read_UINT8(s, value);
  
  	Cmd = (value & 0xf0) >> 4;
  	Sp = (value & 0x0c) >> 2;
  	cbChId = (value & 0x03) >> 0;
  
  	DEBUG_DVC("Cmd=0x%x", Cmd);
  
  	switch (Cmd)
  	{
  		case CAPABILITY_REQUEST_PDU:
  			drdynvc_process_capability_request(drdynvc, Sp, cbChId, s);
  			break;
  
  		case CREATE_REQUEST_PDU:
  			drdynvc_process_create_request(drdynvc, Sp, cbChId, s);
  			break;
  
  		case DATA_FIRST_PDU:
  			drdynvc_process_data_first(drdynvc, Sp, cbChId, s);
  			break;
  
  		case DATA_PDU:
  			drdynvc_process_data(drdynvc, Sp, cbChId, s);
  			break;
  
  		case CLOSE_REQUEST_PDU:
  			drdynvc_process_close_request(drdynvc, Sp, cbChId, s);
  			break;
  
  		default:
  			WLog_ERR(TAG, "unknown drdynvc cmd 0x%x", Cmd);
  			break;
  	}
  }
  
  /****************************************************************************************/
  
  static wListDictionary* g_InitHandles;
  static wListDictionary* g_OpenHandles;
  
  void drdynvc_add_init_handle_data(void* pInitHandle, void* pUserData)
  {
  	if (!g_InitHandles)
  		g_InitHandles = ListDictionary_New(TRUE);
  
  	ListDictionary_Add(g_InitHandles, pInitHandle, pUserData);
  }
  
  void* drdynvc_get_init_handle_data(void* pInitHandle)
  {
  	void* pUserData = NULL;
  	pUserData = ListDictionary_GetItemValue(g_InitHandles, pInitHandle);
  	return pUserData;
  }
  
  void drdynvc_remove_init_handle_data(void* pInitHandle)
  {
  	ListDictionary_Remove(g_InitHandles, pInitHandle);
  }
  
  void drdynvc_add_open_handle_data(DWORD openHandle, void* pUserData)
  {
  	void* pOpenHandle = (void*) (size_t) openHandle;
  
  	if (!g_OpenHandles)
  		g_OpenHandles = ListDictionary_New(TRUE);
  
  	ListDictionary_Add(g_OpenHandles, pOpenHandle, pUserData);
  }
  
  void* drdynvc_get_open_handle_data(DWORD openHandle)
  {
  	void* pUserData = NULL;
  	void* pOpenHandle = (void*) (size_t) openHandle;
  	pUserData = ListDictionary_GetItemValue(g_OpenHandles, pOpenHandle);
  	return pUserData;
  }
  
  void drdynvc_remove_open_handle_data(DWORD openHandle)
  {
  	void* pOpenHandle = (void*) (size_t) openHandle;
  	ListDictionary_Remove(g_OpenHandles, pOpenHandle);
  }
  
  static void drdynvc_virtual_channel_event_data_received(drdynvcPlugin* drdynvc,
  		void* pData, UINT32 dataLength, UINT32 totalLength, UINT32 dataFlags)
  {
  	wStream* data_in;
  
  	if ((dataFlags & CHANNEL_FLAG_SUSPEND) || (dataFlags & CHANNEL_FLAG_RESUME))
  	{
  		return;
  	}
  
  	if (dataFlags & CHANNEL_FLAG_FIRST)
  	{
  		if (drdynvc->data_in)
  			Stream_Free(drdynvc->data_in, TRUE);
  
  		drdynvc->data_in = Stream_New(NULL, totalLength);
  	}
  
  	data_in = drdynvc->data_in;
  	Stream_EnsureRemainingCapacity(data_in, (int) dataLength);
  	Stream_Write(data_in, pData, dataLength);
  
  	if (dataFlags & CHANNEL_FLAG_LAST)
  	{
  		if (Stream_Capacity(data_in) != Stream_GetPosition(data_in))
  		{
  			WLog_ERR(TAG,  "drdynvc_plugin_process_received: read error");
  		}
  
  		drdynvc->data_in = NULL;
  		Stream_SealLength(data_in);
  		Stream_SetPosition(data_in, 0);
  
  		MessageQueue_Post(drdynvc->MsgPipe->In, NULL, 0, (void*) data_in, NULL);
  	}
  }
  
  static VOID VCAPITYPE drdynvc_virtual_channel_open_event(DWORD openHandle, UINT event,
  		LPVOID pData, UINT32 dataLength, UINT32 totalLength, UINT32 dataFlags)
  {
  	drdynvcPlugin* drdynvc;
  
  	drdynvc = (drdynvcPlugin*) drdynvc_get_open_handle_data(openHandle);
  
  	if (!drdynvc)
  	{
  		WLog_ERR(TAG,  "drdynvc_virtual_channel_open_event: error no match");
  		return;
  	}
  
  	switch (event)
  	{
  		case CHANNEL_EVENT_DATA_RECEIVED:
  			drdynvc_virtual_channel_event_data_received(drdynvc, pData, dataLength, totalLength, dataFlags);
  			break;
  
  		case CHANNEL_EVENT_WRITE_COMPLETE:
  			Stream_Free((wStream*) pData, TRUE);
  			break;
  
  		case CHANNEL_EVENT_USER:
  			break;
  	}
  }
  
  static void* drdynvc_virtual_channel_client_thread(void* arg)
  {
  	wStream* data;
  	wMessage message;
  	drdynvcPlugin* drdynvc = (drdynvcPlugin*) arg;
  
  	while (1)
  	{
  		if (!MessageQueue_Wait(drdynvc->MsgPipe->In))
  			break;
  
  		if (MessageQueue_Peek(drdynvc->MsgPipe->In, &message, TRUE))
  		{
  			if (message.id == WMQ_QUIT)
  				break;
  
  			if (message.id == 0)
  			{
  				data = (wStream*) message.wParam;
  				drdynvc_order_recv(drdynvc, data);
  				Stream_Free(data, TRUE);
  			}
  		}
  	}
  
  	ExitThread(0);
  	return NULL;
  }
  
  static void drdynvc_virtual_channel_event_connected(drdynvcPlugin* drdynvc, LPVOID pData, UINT32 dataLength)
  {
  	UINT32 status;
  	UINT32 index;
  	ADDIN_ARGV* args;
  	rdpSettings* settings;
  
  	status = drdynvc->channelEntryPoints.pVirtualChannelOpen(drdynvc->InitHandle,
  		&drdynvc->OpenHandle, drdynvc->channelDef.name, drdynvc_virtual_channel_open_event);
  
  	drdynvc_add_open_handle_data(drdynvc->OpenHandle, drdynvc);
  
  	if (status != CHANNEL_RC_OK)
  	{
  		WLog_ERR(TAG,  "drdynvc_virtual_channel_event_connected: open failed: status: %d", status);
  		return;
  	}
  
  	drdynvc->MsgPipe = MessagePipe_New();
  
  	drdynvc->channel_mgr = dvcman_new(drdynvc);
  	drdynvc->channel_error = 0;
  
  	settings = (rdpSettings*) drdynvc->channelEntryPoints.pExtendedData;
  
  	for (index = 0; index < settings->DynamicChannelCount; index++)
  	{
  		args = settings->DynamicChannelArray[index];
  		dvcman_load_addin(drdynvc->channel_mgr, args, settings);
  	}
  
  	dvcman_init(drdynvc->channel_mgr);
  
  	drdynvc->state = DRDYNVC_STATE_CAPABILITIES;
  
  	drdynvc->thread = CreateThread(NULL, 0,
  			(LPTHREAD_START_ROUTINE) drdynvc_virtual_channel_client_thread, (void*) drdynvc, 0, NULL);
  }
  
  static void drdynvc_virtual_channel_event_terminated(drdynvcPlugin* drdynvc)
  {
  	MessagePipe_PostQuit(drdynvc->MsgPipe, 0);
  	WaitForSingleObject(drdynvc->thread, INFINITE);
  
  	MessagePipe_Free(drdynvc->MsgPipe);
  	CloseHandle(drdynvc->thread);
  
  	drdynvc->channelEntryPoints.pVirtualChannelClose(drdynvc->OpenHandle);
  
  	if (drdynvc->data_in)
  	{
  		Stream_Free(drdynvc->data_in, TRUE);
  		drdynvc->data_in = NULL;
  	}
  
  	if (drdynvc->channel_mgr)
  	{
  		dvcman_free(drdynvc->channel_mgr);
  		drdynvc->channel_mgr = NULL;
  	}
  
  	drdynvc_remove_open_handle_data(drdynvc->OpenHandle);
  	drdynvc_remove_init_handle_data(drdynvc->InitHandle);
  }
  
  static VOID VCAPITYPE drdynvc_virtual_channel_init_event(LPVOID pInitHandle, UINT event, LPVOID pData, UINT dataLength)
  {
  	drdynvcPlugin* drdynvc;
  
  	drdynvc = (drdynvcPlugin*) drdynvc_get_init_handle_data(pInitHandle);
  
  	if (!drdynvc)
  	{
  		WLog_ERR(TAG,  "drdynvc_virtual_channel_init_event: error no match");
  		return;
  	}
  
  	switch (event)
  	{
  		case CHANNEL_EVENT_CONNECTED:
  			drdynvc_virtual_channel_event_connected(drdynvc, pData, dataLength);
  			break;
  
  		case CHANNEL_EVENT_DISCONNECTED:
  			break;
  
  		case CHANNEL_EVENT_TERMINATED:
  			drdynvc_virtual_channel_event_terminated(drdynvc);
  			break;
  	}
  }
  
  /**
   * Channel Client Interface
   */
  
  int drdynvc_get_version(DrdynvcClientContext* context)
  {
  	drdynvcPlugin* drdynvc = (drdynvcPlugin*) context->handle;
  	return drdynvc->version;
  }
  
  /* drdynvc is always built-in */
  #define VirtualChannelEntry	drdynvc_VirtualChannelEntry
  
  BOOL VCAPITYPE VirtualChannelEntry(PCHANNEL_ENTRY_POINTS pEntryPoints)
  {
  	drdynvcPlugin* drdynvc;
  	DrdynvcClientContext* context;
  	CHANNEL_ENTRY_POINTS_FREERDP* pEntryPointsEx;
  
  	drdynvc = (drdynvcPlugin*) calloc(1, sizeof(drdynvcPlugin));
  
  	if (!drdynvc)
  		return FALSE;
  
  	drdynvc->channelDef.options =
  		CHANNEL_OPTION_INITIALIZED |
  		CHANNEL_OPTION_ENCRYPT_RDP |
  		CHANNEL_OPTION_COMPRESS_RDP;
  
  	strcpy(drdynvc->channelDef.name, "drdynvc");
  
  	drdynvc->state = DRDYNVC_STATE_INITIAL;
  
  	pEntryPointsEx = (CHANNEL_ENTRY_POINTS_FREERDP*) pEntryPoints;
  
  	if ((pEntryPointsEx->cbSize >= sizeof(CHANNEL_ENTRY_POINTS_FREERDP)) &&
  			(pEntryPointsEx->MagicNumber == FREERDP_CHANNEL_MAGIC_NUMBER))
  	{
  		context = (DrdynvcClientContext*) calloc(1, sizeof(DrdynvcClientContext));
  
  		if (!context)
  		{
  			free(drdynvc);
  			return -1;
  		}
  
  		context->handle = (void*) drdynvc;
  		context->custom = NULL;
  
  		drdynvc->context = context;
  
  		context->GetVersion = drdynvc_get_version;
  
  		*(pEntryPointsEx->ppInterface) = (void*) context;
  	}
  
  	drdynvc->log = WLog_Get("com.freerdp.channels.drdynvc.client");
  
  	WLog_Print(drdynvc->log, WLOG_DEBUG, "VirtualChannelEntry");
  
  	CopyMemory(&(drdynvc->channelEntryPoints), pEntryPoints, sizeof(CHANNEL_ENTRY_POINTS_FREERDP));
  
  	drdynvc->channelEntryPoints.pVirtualChannelInit(&drdynvc->InitHandle,
  		&drdynvc->channelDef, 1, VIRTUAL_CHANNEL_VERSION_WIN2000, drdynvc_virtual_channel_init_event);
  
  	drdynvc->channelEntryPoints.pInterface = *(drdynvc->channelEntryPoints.ppInterface);
  	drdynvc->channelEntryPoints.ppInterface = &(drdynvc->channelEntryPoints.pInterface);
  
  	drdynvc_add_init_handle_data(drdynvc->InitHandle, (void*) drdynvc);
  
  	return 1;
  }
  
  