/src/FreeRDP/channels/remdesk/client/remdesk_main.c

Source
/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * Remote Assistance Virtual Channel
 *
 * Copyright 2014 Marc-Andre Moreau <marcandre.moreau@gmail.com>
 * Copyright 2015 Thincast Technologies GmbH
 * Copyright 2015 DI (FH) Martin Haimberger <martin.haimberger@thincast.com>
 *
 * 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.
 */

#include <freerdp/config.h>

#include <winpr/crt.h>
#include <winpr/assert.h>
#include <winpr/print.h>

#include <freerdp/freerdp.h>
#include <freerdp/assistance.h>

#include <freerdp/channels/log.h>
#include <freerdp/client/remdesk.h>

#include "remdesk_main.h"
#include "remdesk_common.h"

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_virtual_channel_write(remdeskPlugin* remdesk, wStream* s)
{
  UINT32 status = 0;

  if (!remdesk)
  {
    WLog_ERR(TAG, "remdesk was null!");
    Stream_Free(s, TRUE);
    return CHANNEL_RC_INVALID_INSTANCE;
  }

  WINPR_ASSERT(remdesk->channelEntryPoints.pVirtualChannelWriteEx);
  status = remdesk->channelEntryPoints.pVirtualChannelWriteEx(
      remdesk->InitHandle, remdesk->OpenHandle, Stream_Buffer(s), (UINT32)Stream_Length(s), s);

  if (status != CHANNEL_RC_OK)
  {
    Stream_Free(s, TRUE);
    WLog_ERR(TAG, "pVirtualChannelWriteEx failed with %s [%08" PRIX32 "]",
             WTSErrorToString(status), status);
  }
  return status;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_generate_expert_blob(remdeskPlugin* remdesk)
{
  const char* name = nullptr;
  char* pass = nullptr;
  const char* password = nullptr;
  rdpSettings* settings = nullptr;

  WINPR_ASSERT(remdesk);

  WINPR_ASSERT(remdesk->rdpcontext);
  settings = remdesk->rdpcontext->settings;
  WINPR_ASSERT(settings);

  if (remdesk->ExpertBlob)
    return CHANNEL_RC_OK;

  password = freerdp_settings_get_string(settings, FreeRDP_RemoteAssistancePassword);
  if (!password)
    password = freerdp_settings_get_string(settings, FreeRDP_Password);

  if (!password)
  {
    WLog_ERR(TAG, "password was not set!");
    return ERROR_INTERNAL_ERROR;
  }

  name = freerdp_settings_get_string(settings, FreeRDP_Username);

  if (!name)
    name = "Expert";

  const char* stub = freerdp_settings_get_string(settings, FreeRDP_RemoteAssistancePassStub);
  remdesk->EncryptedPassStub =
      freerdp_assistance_encrypt_pass_stub(password, stub, &(remdesk->EncryptedPassStubSize));

  if (!remdesk->EncryptedPassStub)
  {
    WLog_ERR(TAG, "freerdp_assistance_encrypt_pass_stub failed!");
    return ERROR_INTERNAL_ERROR;
  }

  pass = freerdp_assistance_bin_to_hex_string(remdesk->EncryptedPassStub,
                                              remdesk->EncryptedPassStubSize);

  if (!pass)
  {
    WLog_ERR(TAG, "freerdp_assistance_bin_to_hex_string failed!");
    return ERROR_INTERNAL_ERROR;
  }

  remdesk->ExpertBlob = freerdp_assistance_construct_expert_blob(name, pass);
  free(pass);

  if (!remdesk->ExpertBlob)
  {
    WLog_ERR(TAG, "freerdp_assistance_construct_expert_blob failed!");
    return ERROR_INTERNAL_ERROR;
  }

  return CHANNEL_RC_OK;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT
remdesk_recv_ctl_server_announce_pdu(WINPR_ATTR_UNUSED remdeskPlugin* remdesk,
                                     WINPR_ATTR_UNUSED wStream* s,
                                     WINPR_ATTR_UNUSED const REMDESK_CHANNEL_HEADER* header)
{
  WINPR_ASSERT(remdesk);
  WINPR_ASSERT(s);
  WINPR_ASSERT(header);

  WLog_ERR("TODO", "TODO: implement");
  return CHANNEL_RC_OK;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT
remdesk_recv_ctl_version_info_pdu(remdeskPlugin* remdesk, wStream* s,
                                  WINPR_ATTR_UNUSED const REMDESK_CHANNEL_HEADER* header)
{
  WINPR_ASSERT(remdesk);
  WINPR_ASSERT(s);
  WINPR_ASSERT(header);

  if (header->DataLength < 12ull)
  {
    WLog_ERR(TAG, "remdesk: HEADER::DataLength=%" PRIu32 ", but expected >= 12",
             header->DataLength);
    return ERROR_INVALID_DATA;
  }

  if (!Stream_CheckAndLogRequiredLength(TAG, s, 8))
    return ERROR_INVALID_DATA;

  const UINT32 versionMajor = Stream_Get_UINT32(s); /* versionMajor (4 bytes) */
  const UINT32 versionMinor = Stream_Get_UINT32(s); /* versionMinor (4 bytes) */

  if ((versionMajor != 1) || (versionMinor > 2) || (versionMinor == 0))
  {
    WLog_ERR(TAG, "Unsupported protocol version %" PRIu32 ".%" PRIu32, versionMajor,
             versionMinor);
  }

  remdesk->Version = versionMinor;
  return CHANNEL_RC_OK;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_send_ctl_version_info_pdu(remdeskPlugin* remdesk)
{
  REMDESK_CTL_VERSION_INFO_PDU pdu = WINPR_C_ARRAY_INIT;

  WINPR_ASSERT(remdesk);

  UINT error = remdesk_prepare_ctl_header(&(pdu.ctlHeader), REMDESK_CTL_VERSIONINFO, 8);
  if (error)
    return error;

  pdu.versionMajor = 1;
  pdu.versionMinor = 2;
  wStream* s = Stream_New(nullptr, REMDESK_CHANNEL_CTL_SIZE + pdu.ctlHeader.ch.DataLength);

  if (!s)
  {
    WLog_ERR(TAG, "Stream_New failed!");
    return CHANNEL_RC_NO_MEMORY;
  }

  error = remdesk_write_ctl_header(s, &(pdu.ctlHeader));
  if (error)
  {
    Stream_Free(s, TRUE);
    return error;
  }
  Stream_Write_UINT32(s, pdu.versionMajor); /* versionMajor (4 bytes) */
  Stream_Write_UINT32(s, pdu.versionMinor); /* versionMinor (4 bytes) */
  Stream_SealLength(s);

  if ((error = remdesk_virtual_channel_write(remdesk, s)))
    WLog_ERR(TAG, "remdesk_virtual_channel_write failed with error %" PRIu32 "!", error);

  return error;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_recv_ctl_result_pdu(WINPR_ATTR_UNUSED remdeskPlugin* remdesk, wStream* s,
                                        WINPR_ATTR_UNUSED const REMDESK_CHANNEL_HEADER* header,
                                        UINT32* pResult)
{
  UINT32 result = 0;

  WINPR_ASSERT(remdesk);
  WINPR_ASSERT(s);
  WINPR_ASSERT(header);
  WINPR_ASSERT(pResult);

  if (header->DataLength < 8ull)
  {
    WLog_ERR(TAG, "remdesk: HEADER::DataLength=%" PRIu32 ", but expected >= 8",
             header->DataLength);
    return ERROR_INVALID_DATA;
  }

  if (!Stream_CheckAndLogRequiredLength(TAG, s, 4))
    return ERROR_INVALID_DATA;

  Stream_Read_UINT32(s, result); /* result (4 bytes) */
  *pResult = result;
  // WLog_DBG(TAG, "RemdeskRecvResult: 0x%08"PRIX32"", result);
  switch (result)
  {
    case REMDESK_ERROR_HELPEESAIDNO:
      WLog_DBG(TAG, "remote assistance connection request was denied");
      return ERROR_CONNECTION_REFUSED;

    default:
      break;
  }

  return CHANNEL_RC_OK;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_send_ctl_authenticate_pdu(remdeskPlugin* remdesk)
{
  UINT error = ERROR_INTERNAL_ERROR;
  size_t cbExpertBlobW = 0;
  WCHAR* expertBlobW = nullptr;
  size_t cbRaConnectionStringW = 0;
  REMDESK_CTL_HEADER ctlHeader = WINPR_C_ARRAY_INIT;

  WINPR_ASSERT(remdesk);

  if ((error = remdesk_generate_expert_blob(remdesk)))
  {
    WLog_ERR(TAG, "remdesk_generate_expert_blob failed with error %" PRIu32 "", error);
    return error;
  }

  const char* expertBlob = remdesk->ExpertBlob;
  WINPR_ASSERT(remdesk->rdpcontext);
  rdpSettings* settings = remdesk->rdpcontext->settings;
  WINPR_ASSERT(settings);

  const char* raConnectionString =
      freerdp_settings_get_string(settings, FreeRDP_RemoteAssistanceRCTicket);
  WCHAR* raConnectionStringW =
      ConvertUtf8ToWCharAlloc(raConnectionString, &cbRaConnectionStringW);

  if (!raConnectionStringW || (cbRaConnectionStringW > UINT32_MAX / sizeof(WCHAR)))
    goto out;

  cbRaConnectionStringW = cbRaConnectionStringW * sizeof(WCHAR);

  expertBlobW = ConvertUtf8ToWCharAlloc(expertBlob, &cbExpertBlobW);

  if (!expertBlobW)
    goto out;

  cbExpertBlobW = cbExpertBlobW * sizeof(WCHAR);
  error = remdesk_prepare_ctl_header(&(ctlHeader), REMDESK_CTL_AUTHENTICATE,
                                     cbRaConnectionStringW + cbExpertBlobW);
  if (error)
    goto out;

  {
    wStream* s = Stream_New(nullptr, REMDESK_CHANNEL_CTL_SIZE + ctlHeader.ch.DataLength);
    if (!s)
    {
      WLog_ERR(TAG, "Stream_New failed!");
      error = CHANNEL_RC_NO_MEMORY;
      goto out;
    }

    error = remdesk_write_ctl_header(s, &ctlHeader);
    if (error)
    {
      Stream_Free(s, TRUE);
      goto out;
    }
    Stream_Write(s, raConnectionStringW, cbRaConnectionStringW);
    Stream_Write(s, expertBlobW, cbExpertBlobW);
    Stream_SealLength(s);

    error = remdesk_virtual_channel_write(remdesk, s);
  }
  if (error)
    WLog_ERR(TAG, "remdesk_virtual_channel_write failed with error %" PRIu32 "!", error);

out:
  free(raConnectionStringW);
  free(expertBlobW);

  return error;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_send_ctl_remote_control_desktop_pdu(remdeskPlugin* remdesk)
{
  UINT error = 0;
  size_t length = 0;

  WINPR_ASSERT(remdesk);
  WINPR_ASSERT(remdesk->rdpcontext);
  rdpSettings* settings = remdesk->rdpcontext->settings;
  WINPR_ASSERT(settings);

  const char* raConnectionString =
      freerdp_settings_get_string(settings, FreeRDP_RemoteAssistanceRCTicket);
  WCHAR* raConnectionStringW = ConvertUtf8ToWCharAlloc(raConnectionString, &length);
  size_t cbRaConnectionStringW = length * sizeof(WCHAR);

  if (!raConnectionStringW)
    return ERROR_INTERNAL_ERROR;

  REMDESK_CTL_HEADER ctlHeader = WINPR_C_ARRAY_INIT;
  error = remdesk_prepare_ctl_header(&ctlHeader, REMDESK_CTL_REMOTE_CONTROL_DESKTOP,
                                     cbRaConnectionStringW);
  if (error != CHANNEL_RC_OK)
    goto out;

  {
    wStream* s = Stream_New(nullptr, REMDESK_CHANNEL_CTL_SIZE + ctlHeader.ch.DataLength);

    if (!s)
    {
      WLog_ERR(TAG, "Stream_New failed!");
      error = CHANNEL_RC_NO_MEMORY;
      goto out;
    }

    error = remdesk_write_ctl_header(s, &ctlHeader);
    if (error)
    {
      Stream_Free(s, TRUE);
      goto out;
    }
    Stream_Write(s, raConnectionStringW, cbRaConnectionStringW);
    Stream_SealLength(s);

    if ((error = remdesk_virtual_channel_write(remdesk, s)))
      WLog_ERR(TAG, "remdesk_virtual_channel_write failed with error %" PRIu32 "!", error);
  }

out:
  free(raConnectionStringW);

  return error;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_send_ctl_verify_password_pdu(remdeskPlugin* remdesk)
{
  size_t cbExpertBlobW = 0;
  REMDESK_CTL_VERIFY_PASSWORD_PDU pdu = WINPR_C_ARRAY_INIT;

  WINPR_ASSERT(remdesk);

  UINT error = remdesk_generate_expert_blob(remdesk);
  if (error)
  {
    WLog_ERR(TAG, "remdesk_generate_expert_blob failed with error %" PRIu32 "!", error);
    return error;
  }

  pdu.expertBlob = remdesk->ExpertBlob;
  WCHAR* expertBlobW = ConvertUtf8ToWCharAlloc(pdu.expertBlob, &cbExpertBlobW);

  if (!expertBlobW)
    goto out;

  cbExpertBlobW = cbExpertBlobW * sizeof(WCHAR);
  error =
      remdesk_prepare_ctl_header(&(pdu.ctlHeader), REMDESK_CTL_VERIFY_PASSWORD, cbExpertBlobW);
  if (error)
    goto out;

  {
    wStream* s =
        Stream_New(nullptr, 1ULL * REMDESK_CHANNEL_CTL_SIZE + pdu.ctlHeader.ch.DataLength);

    if (!s)
    {
      WLog_ERR(TAG, "Stream_New failed!");
      error = CHANNEL_RC_NO_MEMORY;
      goto out;
    }

    error = remdesk_write_ctl_header(s, &(pdu.ctlHeader));
    if (error)
    {
      Stream_Free(s, TRUE);
      goto out;
    }
    Stream_Write(s, expertBlobW, cbExpertBlobW);
    Stream_SealLength(s);

    error = remdesk_virtual_channel_write(remdesk, s);
  }
  if (error)
    WLog_ERR(TAG, "remdesk_virtual_channel_write failed with error %" PRIu32 "!", error);

out:
  free(expertBlobW);

  return error;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_send_ctl_expert_on_vista_pdu(remdeskPlugin* remdesk)
{
  REMDESK_CTL_EXPERT_ON_VISTA_PDU pdu = WINPR_C_ARRAY_INIT;

  WINPR_ASSERT(remdesk);

  UINT error = remdesk_generate_expert_blob(remdesk);
  if (error)
  {
    WLog_ERR(TAG, "remdesk_generate_expert_blob failed with error %" PRIu32 "!", error);
    return error;
  }
  if (remdesk->EncryptedPassStubSize > UINT32_MAX)
    return ERROR_INTERNAL_ERROR;

  pdu.EncryptedPasswordLength = (UINT32)remdesk->EncryptedPassStubSize;
  pdu.EncryptedPassword = remdesk->EncryptedPassStub;
  error = remdesk_prepare_ctl_header(&(pdu.ctlHeader), REMDESK_CTL_EXPERT_ON_VISTA,
                                     pdu.EncryptedPasswordLength);
  if (error)
    return error;

  wStream* s = Stream_New(nullptr, REMDESK_CHANNEL_CTL_SIZE + pdu.ctlHeader.ch.DataLength);

  if (!s)
  {
    WLog_ERR(TAG, "Stream_New failed!");
    return CHANNEL_RC_NO_MEMORY;
  }

  error = remdesk_write_ctl_header(s, &(pdu.ctlHeader));
  if (error)
  {
    Stream_Free(s, TRUE);
    return error;
  }
  Stream_Write(s, pdu.EncryptedPassword, pdu.EncryptedPasswordLength);
  Stream_SealLength(s);
  return remdesk_virtual_channel_write(remdesk, s);
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_recv_ctl_pdu(remdeskPlugin* remdesk, wStream* s,
                                 const REMDESK_CHANNEL_HEADER* header)
{
  UINT error = CHANNEL_RC_OK;
  UINT32 msgType = 0;
  UINT32 result = 0;

  WINPR_ASSERT(remdesk);
  WINPR_ASSERT(s);
  WINPR_ASSERT(header);

  if (header->DataLength < 4)
  {
    WLog_ERR(TAG, "remdesk: HEADER::DataLength=%" PRIu32 ", but expected >= 4",
             header->DataLength);
    return ERROR_INVALID_DATA;
  }

  if (!Stream_CheckAndLogRequiredLength(TAG, s, header->DataLength))
    return ERROR_INVALID_DATA;

  Stream_Read_UINT32(s, msgType); /* msgType (4 bytes) */

  // WLog_DBG(TAG, "msgType: %"PRIu32"", msgType);

  switch (msgType)
  {
    case REMDESK_CTL_REMOTE_CONTROL_DESKTOP:
      break;

    case REMDESK_CTL_RESULT:
      if ((error = remdesk_recv_ctl_result_pdu(remdesk, s, header, &result)))
        WLog_ERR(TAG, "remdesk_recv_ctl_result_pdu failed with error %" PRIu32 "", error);

      break;

    case REMDESK_CTL_AUTHENTICATE:
      break;

    case REMDESK_CTL_SERVER_ANNOUNCE:
      if ((error = remdesk_recv_ctl_server_announce_pdu(remdesk, s, header)))
        WLog_ERR(TAG, "remdesk_recv_ctl_server_announce_pdu failed with error %" PRIu32 "",
                 error);

      break;

    case REMDESK_CTL_DISCONNECT:
      break;

    case REMDESK_CTL_VERSIONINFO:
      if ((error = remdesk_recv_ctl_version_info_pdu(remdesk, s, header)))
      {
        WLog_ERR(TAG, "remdesk_recv_ctl_version_info_pdu failed with error %" PRIu32 "",
                 error);
        break;
      }

      if (remdesk->Version == 1)
      {
        if ((error = remdesk_send_ctl_version_info_pdu(remdesk)))
        {
          WLog_ERR(TAG, "remdesk_send_ctl_version_info_pdu failed with error %" PRIu32 "",
                   error);
          break;
        }

        if ((error = remdesk_send_ctl_authenticate_pdu(remdesk)))
        {
          WLog_ERR(TAG, "remdesk_send_ctl_authenticate_pdu failed with error %" PRIu32 "",
                   error);
          break;
        }

        if ((error = remdesk_send_ctl_remote_control_desktop_pdu(remdesk)))
        {
          WLog_ERR(
              TAG,
              "remdesk_send_ctl_remote_control_desktop_pdu failed with error %" PRIu32 "",
              error);
          break;
        }
      }
      else if (remdesk->Version == 2)
      {
        if ((error = remdesk_send_ctl_expert_on_vista_pdu(remdesk)))
        {
          WLog_ERR(TAG,
                   "remdesk_send_ctl_expert_on_vista_pdu failed with error %" PRIu32 "",
                   error);
          break;
        }

        if ((error = remdesk_send_ctl_verify_password_pdu(remdesk)))
        {
          WLog_ERR(TAG,
                   "remdesk_send_ctl_verify_password_pdu failed with error %" PRIu32 "",
                   error);
          break;
        }
      }

      break;

    case REMDESK_CTL_ISCONNECTED:
      break;

    case REMDESK_CTL_VERIFY_PASSWORD:
      break;

    case REMDESK_CTL_EXPERT_ON_VISTA:
      break;

    case REMDESK_CTL_RANOVICE_NAME:
      break;

    case REMDESK_CTL_RAEXPERT_NAME:
      break;

    case REMDESK_CTL_TOKEN:
      break;

    default:
      WLog_ERR(TAG, "unknown msgType: %" PRIu32 "", msgType);
      error = ERROR_INVALID_DATA;
      break;
  }

  return error;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_process_receive(remdeskPlugin* remdesk, wStream* s)
{
  REMDESK_CHANNEL_HEADER header = WINPR_C_ARRAY_INIT;

  WINPR_ASSERT(remdesk);
  WINPR_ASSERT(s);

  UINT status = remdesk_read_channel_header(s, &header);
  if (status)
  {
    WLog_ERR(TAG, "remdesk_read_channel_header failed with error %" PRIu32 "", status);
    return status;
  }

  if (strcmp(header.ChannelName, "RC_CTL") == 0)
  {
    status = remdesk_recv_ctl_pdu(remdesk, s, &header);
  }
  else if (strcmp(header.ChannelName, "70") == 0)
  {
  }
  else if (strcmp(header.ChannelName, "71") == 0)
  {
  }
  else if (strcmp(header.ChannelName, ".") == 0)
  {
  }
  else if (strcmp(header.ChannelName, "1000.") == 0)
  {
  }
  else if (strcmp(header.ChannelName, "RA_FX") == 0)
  {
  }
  else
  {
  }

  return status;
}

static void remdesk_process_connect(WINPR_ATTR_UNUSED remdeskPlugin* remdesk)
{
  WINPR_ASSERT(remdesk);
  WLog_ERR("TODO", "TODO: implement");
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_virtual_channel_event_data_received(remdeskPlugin* remdesk, const void* pData,
                                                        UINT32 dataLength, UINT32 totalLength,
                                                        UINT32 dataFlags)
{
  WINPR_ASSERT(remdesk);

  if ((dataFlags & CHANNEL_FLAG_SUSPEND) || (dataFlags & CHANNEL_FLAG_RESUME))
  {
    return CHANNEL_RC_OK;
  }

  if (dataFlags & CHANNEL_FLAG_FIRST)
  {
    if (remdesk->firstFlagReceived)
      return ERROR_INVALID_DATA;

    if (remdesk->data_in)
      Stream_Free(remdesk->data_in, TRUE);

    remdesk->data_in = Stream_New(nullptr, dataLength);

    if (!remdesk->data_in)
    {
      WLog_ERR(TAG, "Stream_New failed!");
      return CHANNEL_RC_NO_MEMORY;
    }
    remdesk->firstFlagReceived = TRUE;
    remdesk->totalLength = totalLength;
  }

  wStream* data_in = remdesk->data_in;
  if (!data_in)
    return ERROR_INVALID_DATA;

  if (!Stream_EnsureRemainingCapacity(data_in, dataLength))
  {
    WLog_ERR(TAG, "Stream_EnsureRemainingCapacity failed!");
    return CHANNEL_RC_NO_MEMORY;
  }

  Stream_Write(data_in, pData, dataLength);
  if ((Stream_GetPosition(data_in) > totalLength) || (remdesk->totalLength != totalLength))
    return ERROR_INVALID_DATA;

  if (dataFlags & CHANNEL_FLAG_LAST)
  {
    if (!remdesk->firstFlagReceived)
      return ERROR_INVALID_DATA;
    remdesk->firstFlagReceived = FALSE;

    if (remdesk->totalLength != Stream_GetPosition(data_in))
    {
      WLog_ERR(TAG, "read error");
      return ERROR_INTERNAL_ERROR;
    }

    remdesk->totalLength = 0;
    remdesk->data_in = nullptr;
    Stream_SealLength(data_in);
    Stream_ResetPosition(data_in);

    if (!MessageQueue_Post(remdesk->queue, nullptr, 0, (void*)data_in, nullptr))
    {
      WLog_ERR(TAG, "MessageQueue_Post failed!");
      return ERROR_INTERNAL_ERROR;
    }
  }

  return CHANNEL_RC_OK;
}

static VOID VCAPITYPE remdesk_virtual_channel_open_event_ex(LPVOID lpUserParam, DWORD openHandle,
                                                            UINT event, LPVOID pData,
                                                            UINT32 dataLength, UINT32 totalLength,
                                                            UINT32 dataFlags)
{
  UINT error = CHANNEL_RC_OK;
  remdeskPlugin* remdesk = (remdeskPlugin*)lpUserParam;

  switch (event)
  {
    case CHANNEL_EVENT_INITIALIZED:
      break;

    case CHANNEL_EVENT_DATA_RECEIVED:
      if (!remdesk || (remdesk->OpenHandle != openHandle))
      {
        WLog_ERR(TAG, "error no match");
        return;
      }
      if ((error = remdesk_virtual_channel_event_data_received(remdesk, pData, dataLength,
                                                               totalLength, dataFlags)))
        WLog_ERR(TAG,
                 "remdesk_virtual_channel_event_data_received failed with error %" PRIu32
                 "!",
                 error);

      break;

    case CHANNEL_EVENT_WRITE_CANCELLED:
    case CHANNEL_EVENT_WRITE_COMPLETE:
    {
      wStream* s = (wStream*)pData;
      Stream_Free(s, TRUE);
    }
    break;

    case CHANNEL_EVENT_USER:
      break;

    default:
      WLog_ERR(TAG, "unhandled event %" PRIu32 "!", event);
      error = ERROR_INTERNAL_ERROR;
      break;
  }

  if (error && remdesk && remdesk->rdpcontext)
    setChannelError(remdesk->rdpcontext, error,
                    "remdesk_virtual_channel_open_event_ex reported an error");
}

WINPR_ATTR_NODISCARD
static DWORD WINAPI remdesk_virtual_channel_client_thread(LPVOID arg)
{
  wStream* data = nullptr;
  wMessage message = WINPR_C_ARRAY_INIT;
  remdeskPlugin* remdesk = (remdeskPlugin*)arg;
  UINT error = CHANNEL_RC_OK;

  WINPR_ASSERT(remdesk);

  remdesk_process_connect(remdesk);

  while (1)
  {
    if (!MessageQueue_Wait(remdesk->queue))
    {
      WLog_ERR(TAG, "MessageQueue_Wait failed!");
      error = ERROR_INTERNAL_ERROR;
      break;
    }

    if (!MessageQueue_Peek(remdesk->queue, &message, TRUE))
    {
      WLog_ERR(TAG, "MessageQueue_Peek failed!");
      error = ERROR_INTERNAL_ERROR;
      break;
    }

    if (message.id == WMQ_QUIT)
      break;

    if (message.id == 0)
    {
      data = (wStream*)message.wParam;

      if ((error = remdesk_process_receive(remdesk, data)))
      {
        WLog_ERR(TAG, "remdesk_process_receive failed with error %" PRIu32 "!", error);
        Stream_Free(data, TRUE);
        break;
      }

      Stream_Free(data, TRUE);
    }
  }

  if (error && remdesk->rdpcontext)
    setChannelError(remdesk->rdpcontext, error,
                    "remdesk_virtual_channel_client_thread reported an error");

  ExitThread(error);
  return error;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_virtual_channel_event_connected(remdeskPlugin* remdesk,
                                                    WINPR_ATTR_UNUSED LPVOID pData,
                                                    WINPR_ATTR_UNUSED UINT32 dataLength)
{
  UINT error = 0;

  WINPR_ASSERT(remdesk);

  remdesk->queue = MessageQueue_New(nullptr);

  if (!remdesk->queue)
  {
    WLog_ERR(TAG, "MessageQueue_New failed!");
    error = CHANNEL_RC_NO_MEMORY;
    goto error_out;
  }

  remdesk->thread =
      CreateThread(nullptr, 0, remdesk_virtual_channel_client_thread, (void*)remdesk, 0, nullptr);

  if (!remdesk->thread)
  {
    WLog_ERR(TAG, "CreateThread failed");
    error = ERROR_INTERNAL_ERROR;
    goto error_out;
  }

  return remdesk->channelEntryPoints.pVirtualChannelOpenEx(
      remdesk->InitHandle, &remdesk->OpenHandle, remdesk->channelDef.name,
      remdesk_virtual_channel_open_event_ex);
error_out:
  MessageQueue_Free(remdesk->queue);
  remdesk->queue = nullptr;
  return error;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
WINPR_ATTR_NODISCARD
static UINT remdesk_virtual_channel_event_disconnected(remdeskPlugin* remdesk)
{
  UINT rc = CHANNEL_RC_OK;

  WINPR_ASSERT(remdesk);

  if (remdesk->queue && remdesk->thread)
  {
    if (MessageQueue_PostQuit(remdesk->queue, 0) &&
        (WaitForSingleObject(remdesk->thread, INFINITE) == WAIT_FAILED))
    {
      rc = GetLastError();
      WLog_ERR(TAG, "WaitForSingleObject failed with error %" PRIu32 "", rc);
      return rc;
    }
  }

  if (remdesk->OpenHandle != 0)
  {
    WINPR_ASSERT(remdesk->channelEntryPoints.pVirtualChannelCloseEx);
    rc = remdesk->channelEntryPoints.pVirtualChannelCloseEx(remdesk->InitHandle,
                                                            remdesk->OpenHandle);

    if (CHANNEL_RC_OK != rc)
    {
      WLog_ERR(TAG, "pVirtualChannelCloseEx failed with %s [%08" PRIX32 "]",
               WTSErrorToString(rc), rc);
    }

    remdesk->OpenHandle = 0;
  }
  MessageQueue_Free(remdesk->queue);
  (void)CloseHandle(remdesk->thread);
  Stream_Free(remdesk->data_in, TRUE);
  remdesk->data_in = nullptr;
  remdesk->queue = nullptr;
  remdesk->thread = nullptr;
  return rc;
}

static void remdesk_virtual_channel_event_terminated(remdeskPlugin* remdesk)
{
  WINPR_ASSERT(remdesk);

  remdesk->InitHandle = nullptr;
  free(remdesk->context);
  free(remdesk);
}

static VOID VCAPITYPE remdesk_virtual_channel_init_event_ex(LPVOID lpUserParam, LPVOID pInitHandle,
                                                            UINT event, LPVOID pData,
                                                            UINT dataLength)
{
  UINT error = CHANNEL_RC_OK;
  remdeskPlugin* remdesk = (remdeskPlugin*)lpUserParam;

  if (!remdesk || (remdesk->InitHandle != pInitHandle))
  {
    WLog_ERR(TAG, "error no match");
    return;
  }

  switch (event)
  {
    case CHANNEL_EVENT_CONNECTED:
      if ((error = remdesk_virtual_channel_event_connected(remdesk, pData, dataLength)))
        WLog_ERR(TAG,
                 "remdesk_virtual_channel_event_connected failed with error %" PRIu32 "",
                 error);

      break;

    case CHANNEL_EVENT_DISCONNECTED:
      if ((error = remdesk_virtual_channel_event_disconnected(remdesk)))
        WLog_ERR(TAG,
                 "remdesk_virtual_channel_event_disconnected failed with error %" PRIu32 "",
                 error);

      break;

    case CHANNEL_EVENT_TERMINATED:
      remdesk_virtual_channel_event_terminated(remdesk);
      break;

    case CHANNEL_EVENT_ATTACHED:
    case CHANNEL_EVENT_DETACHED:
    default:
      break;
  }

  if (error && remdesk->rdpcontext)
    setChannelError(remdesk->rdpcontext, error,
                    "remdesk_virtual_channel_init_event reported an error");
}

/* remdesk is always built-in */
#define VirtualChannelEntryEx remdesk_VirtualChannelEntryEx

FREERDP_ENTRY_POINT(BOOL VCAPITYPE VirtualChannelEntryEx(PCHANNEL_ENTRY_POINTS_EX pEntryPoints,
                                                         PVOID pInitHandle))
{
  UINT rc = 0;
  remdeskPlugin* remdesk = nullptr;
  RemdeskClientContext* context = nullptr;
  CHANNEL_ENTRY_POINTS_FREERDP_EX* pEntryPointsEx = nullptr;

  if (!pEntryPoints)
  {
    return FALSE;
  }

  remdesk = (remdeskPlugin*)calloc(1, sizeof(remdeskPlugin));

  if (!remdesk)
  {
    WLog_ERR(TAG, "calloc failed!");
    return FALSE;
  }

  remdesk->channelDef.options = CHANNEL_OPTION_INITIALIZED | CHANNEL_OPTION_ENCRYPT_RDP |
                                CHANNEL_OPTION_COMPRESS_RDP | CHANNEL_OPTION_SHOW_PROTOCOL;
  (void)sprintf_s(remdesk->channelDef.name, ARRAYSIZE(remdesk->channelDef.name),
                  REMDESK_SVC_CHANNEL_NAME);
  remdesk->Version = 2;
  pEntryPointsEx = (CHANNEL_ENTRY_POINTS_FREERDP_EX*)pEntryPoints;

  if ((pEntryPointsEx->cbSize >= sizeof(CHANNEL_ENTRY_POINTS_FREERDP_EX)) &&
      (pEntryPointsEx->MagicNumber == FREERDP_CHANNEL_MAGIC_NUMBER))
  {
    context = (RemdeskClientContext*)calloc(1, sizeof(RemdeskClientContext));

    if (!context)
    {
      WLog_ERR(TAG, "calloc failed!");
      goto error_out;
    }

    context->handle = (void*)remdesk;
    remdesk->context = context;
    remdesk->rdpcontext = pEntryPointsEx->context;
  }

  CopyMemory(&(remdesk->channelEntryPoints), pEntryPoints,
             sizeof(CHANNEL_ENTRY_POINTS_FREERDP_EX));
  remdesk->InitHandle = pInitHandle;
  rc = remdesk->channelEntryPoints.pVirtualChannelInitEx(
      remdesk, context, pInitHandle, &remdesk->channelDef, 1, VIRTUAL_CHANNEL_VERSION_WIN2000,
      remdesk_virtual_channel_init_event_ex);

  if (CHANNEL_RC_OK != rc)
  {
    WLog_ERR(TAG, "pVirtualChannelInitEx failed with %s [%08" PRIX32 "]", WTSErrorToString(rc),
             rc);
    goto error_out;
  }

  remdesk->channelEntryPoints.pInterface = context;
  return TRUE;
error_out:
  free(remdesk);
  free(context);
  return FALSE;
}

Coverage Report

Created: 2026-10-15 06:30