Milestone 5: deliver embedded RDP sessions and lifecycle hardening

third_party/FreeRDP/channels/remdesk/CMakeLists.txt

@@ -0,0 +1,29 @@
+# FreeRDP: A Remote Desktop Protocol Implementation
+# FreeRDP cmake build script
+#
+# Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.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.
+
+define_channel("remdesk")
+
+include_directories(common)
+add_subdirectory(common)
+
+if(WITH_CLIENT_CHANNELS)
+  add_channel_client(${MODULE_PREFIX} ${CHANNEL_NAME})
+endif()
+
+if(WITH_SERVER_CHANNELS)
+  add_channel_server(${MODULE_PREFIX} ${CHANNEL_NAME})
+endif()

third_party/FreeRDP/channels/remdesk/ChannelOptions.cmake

@@ -0,0 +1,20 @@
+set(OPTION_DEFAULT ON)
+set(OPTION_CLIENT_DEFAULT ON)
+set(OPTION_SERVER_DEFAULT ON)
+
+define_channel_options(
+  NAME
+  "remdesk"
+  TYPE
+  "static"
+  DESCRIPTION
+  "Remote Assistance Virtual Channel Extension"
+  SPECIFICATIONS
+  "[MS-RA]"
+  DEFAULT
+  ${OPTION_DEFAULT}
+  CLIENT_DEFAULT
+  ${OPTION_CLIENT_DEFAULT}
+  SERVER_DEFAULT
+  ${OPTION_SERVER_DEFAULT}
+)

third_party/FreeRDP/channels/remdesk/client/CMakeLists.txt

@@ -0,0 +1,24 @@
+# FreeRDP: A Remote Desktop Protocol Implementation
+# FreeRDP cmake build script
+#
+# Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.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.
+
+define_channel_client("remdesk")
+
+set(${MODULE_PREFIX}_SRCS remdesk_main.c remdesk_main.h)
+
+set(${MODULE_PREFIX}_LIBS winpr freerdp remdesk-common)
+
+add_channel_client_library(${MODULE_PREFIX} ${MODULE_NAME} ${CHANNEL_NAME} FALSE "VirtualChannelEntryEx")

third_party/FreeRDP/channels/remdesk/client/remdesk_main.h

@@ -0,0 +1,61 @@
+/**
+ * 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.
+ */
+
+#ifndef FREERDP_CHANNEL_REMDESK_CLIENT_MAIN_H
+#define FREERDP_CHANNEL_REMDESK_CLIENT_MAIN_H
+
+#include <winpr/crt.h>
+#include <winpr/synch.h>
+#include <winpr/thread.h>
+#include <winpr/stream.h>
+#include <winpr/collections.h>
+
+#include <freerdp/api.h>
+#include <freerdp/svc.h>
+#include <freerdp/addin.h>
+#include <freerdp/settings.h>
+
+#include <freerdp/client/remdesk.h>
+
+#include <freerdp/channels/log.h>
+#define TAG CHANNELS_TAG("remdesk.client")
+
+typedef struct
+{
+	CHANNEL_DEF channelDef;
+	CHANNEL_ENTRY_POINTS_FREERDP_EX channelEntryPoints;
+
+	RemdeskClientContext* context;
+
+	HANDLE thread;
+	wStream* data_in;
+	void* InitHandle;
+	DWORD OpenHandle;
+	wMessageQueue* queue;
+
+	UINT32 Version;
+	char* ExpertBlob;
+	BYTE* EncryptedPassStub;
+	size_t EncryptedPassStubSize;
+	rdpContext* rdpcontext;
+} remdeskPlugin;
+
+#endif /* FREERDP_CHANNEL_REMDESK_CLIENT_MAIN_H */

third_party/FreeRDP/channels/remdesk/common/CMakeLists.txt

@@ -0,0 +1,25 @@
+# FreeRDP: A Remote Desktop Protocol Implementation
+# FreeRDP cmake build script
+#
+# Copyright 2024 Armin Novak <armin.novak@thincast.com>
+# Copyright 2024 Thincast Technologies GmbH
+#
+# 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.
+
+set(SRCS remdesk_common.h remdesk_common.c)
+
+add_library(remdesk-common STATIC ${SRCS})
+set_property(TARGET remdesk-common PROPERTY FOLDER "Channels/${CHANNEL_NAME}/Common")
+
+freerdp_client_pc_add_library_private(remdesk-common)
+channel_install(remdesk-common ${FREERDP_ADDIN_PATH} "FreeRDPTargets")

third_party/FreeRDP/channels/remdesk/common/remdesk_common.c

@@ -0,0 +1,105 @@
+/**
+ * FreeRDP: A Remote Desktop Protocol Implementation
+ * Remote Assistance Virtual Channel - common components
+ *
+ * Copyright 2024 Armin Novak <armin.novak@thincast.com>
+ * Copyright 2024 Thincast Technologies GmbH
+ *
+ * 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 "remdesk_common.h"
+
+#include <freerdp/channels/log.h>
+#define TAG CHANNELS_TAG("remdesk.common")
+
+UINT remdesk_write_channel_header(wStream* s, const REMDESK_CHANNEL_HEADER* header)
+{
+	WCHAR ChannelNameW[32] = WINPR_C_ARRAY_INIT;
+
+	WINPR_ASSERT(s);
+	WINPR_ASSERT(header);
+
+	for (size_t index = 0; index < 32; index++)
+	{
+		ChannelNameW[index] = (WCHAR)header->ChannelName[index];
+	}
+
+	const size_t ChannelNameLen =
+	    (strnlen(header->ChannelName, sizeof(header->ChannelName)) + 1) * sizeof(WCHAR);
+	WINPR_ASSERT(ChannelNameLen <= ARRAYSIZE(header->ChannelName));
+
+	Stream_Write_UINT32(s, (UINT32)ChannelNameLen); /* ChannelNameLen (4 bytes) */
+	Stream_Write_UINT32(s, header->DataLength);     /* DataLen (4 bytes) */
+	Stream_Write(s, ChannelNameW, ChannelNameLen);  /* ChannelName (variable) */
+	return CHANNEL_RC_OK;
+}
+
+UINT remdesk_write_ctl_header(wStream* s, const REMDESK_CTL_HEADER* ctlHeader)
+{
+	WINPR_ASSERT(ctlHeader);
+	const UINT error = remdesk_write_channel_header(s, &ctlHeader->ch);
+
+	if (error != 0)
+	{
+		WLog_ERR(TAG, "remdesk_write_channel_header failed with error %" PRIu32 "!", error);
+		return error;
+	}
+
+	Stream_Write_UINT32(s, ctlHeader->msgType); /* msgType (4 bytes) */
+	return CHANNEL_RC_OK;
+}
+
+UINT remdesk_read_channel_header(wStream* s, REMDESK_CHANNEL_HEADER* header)
+{
+	UINT32 ChannelNameLen = 0;
+
+	if (!Stream_CheckAndLogRequiredLength(TAG, s, 8))
+		return CHANNEL_RC_NO_MEMORY;
+
+	Stream_Read_UINT32(s, ChannelNameLen);     /* ChannelNameLen (4 bytes) */
+	Stream_Read_UINT32(s, header->DataLength); /* DataLen (4 bytes) */
+
+	if (ChannelNameLen > 64)
+	{
+		WLog_ERR(TAG, "ChannelNameLen > 64!");
+		return ERROR_INVALID_DATA;
+	}
+
+	if ((ChannelNameLen % 2) != 0)
+	{
+		WLog_ERR(TAG, "(ChannelNameLen %% 2) != 0!");
+		return ERROR_INVALID_DATA;
+	}
+
+	if (Stream_Read_UTF16_String_As_UTF8_Buffer(s, ChannelNameLen / sizeof(WCHAR),
+	                                            header->ChannelName,
+	                                            ARRAYSIZE(header->ChannelName)) < 0)
+		return ERROR_INVALID_DATA;
+
+	return CHANNEL_RC_OK;
+}
+
+UINT remdesk_prepare_ctl_header(REMDESK_CTL_HEADER* ctlHeader, UINT32 msgType, size_t msgSize)
+{
+	WINPR_ASSERT(ctlHeader);
+
+	if (msgSize > UINT32_MAX - 4)
+		return ERROR_INVALID_PARAMETER;
+
+	ctlHeader->msgType = msgType;
+	(void)sprintf_s(ctlHeader->ch.ChannelName, ARRAYSIZE(ctlHeader->ch.ChannelName),
+	                REMDESK_CHANNEL_CTL_NAME);
+	ctlHeader->ch.DataLength = (UINT32)(4UL + msgSize);
+	return CHANNEL_RC_OK;
+}

third_party/FreeRDP/channels/remdesk/common/remdesk_common.h

@@ -0,0 +1,39 @@
+/**
+ * FreeRDP: A Remote Desktop Protocol Implementation
+ * Remote Assistance Virtual Channel - common components
+ *
+ * Copyright 2024 Armin Novak <armin.novak@thincast.com>
+ * Copyright 2024 Thincast Technologies GmbH
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include <winpr/wtypes.h>
+#include <winpr/stream.h>
+
+#include <freerdp/channels/remdesk.h>
+
+WINPR_ATTR_NODISCARD
+FREERDP_LOCAL UINT remdesk_write_channel_header(wStream* s, const REMDESK_CHANNEL_HEADER* header);
+
+WINPR_ATTR_NODISCARD
+FREERDP_LOCAL UINT remdesk_write_ctl_header(wStream* s, const REMDESK_CTL_HEADER* ctlHeader);
+
+WINPR_ATTR_NODISCARD
+FREERDP_LOCAL UINT remdesk_read_channel_header(wStream* s, REMDESK_CHANNEL_HEADER* header);
+
+WINPR_ATTR_NODISCARD
+FREERDP_LOCAL UINT remdesk_prepare_ctl_header(REMDESK_CTL_HEADER* ctlHeader, UINT32 msgType,
+                                              size_t msgSize);

third_party/FreeRDP/channels/remdesk/server/CMakeLists.txt

@@ -0,0 +1,24 @@
+# FreeRDP: A Remote Desktop Protocol Implementation
+# FreeRDP cmake build script
+#
+# Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.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.
+
+define_channel_server("remdesk")
+
+set(${MODULE_PREFIX}_SRCS remdesk_main.c remdesk_main.h)
+
+set(${MODULE_PREFIX}_LIBS winpr remdesk-common)
+
+add_channel_server_library(${MODULE_PREFIX} ${MODULE_NAME} ${CHANNEL_NAME} FALSE "VirtualChannelEntry")

third_party/FreeRDP/channels/remdesk/server/remdesk_main.c

@@ -0,0 +1,642 @@
+/**
+ * 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/print.h>
+#include <winpr/stream.h>
+
+#include <freerdp/freerdp.h>
+
+#include "remdesk_main.h"
+#include "remdesk_common.h"
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_virtual_channel_write(RemdeskServerContext* context, wStream* s)
+{
+	const size_t len = Stream_Length(s);
+	WINPR_ASSERT(len <= UINT32_MAX);
+	ULONG BytesWritten = 0;
+	BOOL status = WTSVirtualChannelWrite(context->priv->ChannelHandle, Stream_BufferAs(s, char),
+	                                     (UINT32)len, &BytesWritten);
+	return (status) ? CHANNEL_RC_OK : ERROR_INTERNAL_ERROR;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_send_ctl_result_pdu(RemdeskServerContext* context, UINT32 result)
+{
+	wStream* s = nullptr;
+	REMDESK_CTL_RESULT_PDU pdu;
+	UINT error = 0;
+	pdu.result = result;
+
+	if ((error = remdesk_prepare_ctl_header(&(pdu.ctlHeader), REMDESK_CTL_RESULT, 4)))
+	{
+		WLog_ERR(TAG, "remdesk_prepare_ctl_header failed with error %" PRIu32 "!", error);
+		return error;
+	}
+
+	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;
+	}
+
+	if ((error = remdesk_write_ctl_header(s, &(pdu.ctlHeader))))
+	{
+		WLog_ERR(TAG, "remdesk_write_ctl_header failed with error %" PRIu32 "!", error);
+		goto out;
+	}
+
+	Stream_Write_UINT32(s, pdu.result); /* result (4 bytes) */
+	Stream_SealLength(s);
+
+	if ((error = remdesk_virtual_channel_write(context, s)))
+		WLog_ERR(TAG, "remdesk_virtual_channel_write failed with error %" PRIu32 "!", error);
+
+out:
+	Stream_Free(s, TRUE);
+	return error;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_send_ctl_version_info_pdu(RemdeskServerContext* context)
+{
+	wStream* s = nullptr;
+	REMDESK_CTL_VERSION_INFO_PDU pdu;
+	UINT error = 0;
+
+	if ((error = remdesk_prepare_ctl_header(&(pdu.ctlHeader), REMDESK_CTL_VERSIONINFO, 8)))
+	{
+		WLog_ERR(TAG, "remdesk_prepare_ctl_header failed with error %" PRIu32 "!", error);
+		return error;
+	}
+
+	pdu.versionMajor = 1;
+	pdu.versionMinor = 2;
+	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;
+	}
+
+	if ((error = remdesk_write_ctl_header(s, &(pdu.ctlHeader))))
+	{
+		WLog_ERR(TAG, "remdesk_write_ctl_header failed with error %" PRIu32 "!", error);
+		goto out;
+	}
+
+	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(context, s)))
+		WLog_ERR(TAG, "remdesk_virtual_channel_write failed with error %" PRIu32 "!", error);
+
+out:
+	Stream_Free(s, TRUE);
+	return error;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_recv_ctl_version_info_pdu(WINPR_ATTR_UNUSED RemdeskServerContext* context,
+                                              wStream* s,
+                                              WINPR_ATTR_UNUSED REMDESK_CHANNEL_HEADER* header)
+{
+	UINT32 versionMajor = 0;
+	UINT32 versionMinor = 0;
+
+	if (!Stream_CheckAndLogRequiredLength(TAG, s, 8))
+		return ERROR_INVALID_DATA;
+
+	Stream_Read_UINT32(s, versionMajor); /* versionMajor (4 bytes) */
+	Stream_Read_UINT32(s, versionMinor); /* versionMinor (4 bytes) */
+	if ((versionMajor != 1) || (versionMinor != 2))
+	{
+		WLog_ERR(TAG, "REMOTEDESKTOP_CTL_VERSIONINFO_PACKET invalid version %" PRIu32 ".%" PRIu32,
+		         versionMajor, versionMinor);
+		return ERROR_INVALID_DATA;
+	}
+
+	return CHANNEL_RC_OK;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_recv_ctl_remote_control_desktop_pdu(RemdeskServerContext* context, wStream* s,
+                                                        REMDESK_CHANNEL_HEADER* header)
+{
+	size_t cchStringW = 0;
+	REMDESK_CTL_REMOTE_CONTROL_DESKTOP_PDU pdu = WINPR_C_ARRAY_INIT;
+	UINT error = 0;
+	UINT32 msgLength = header->DataLength - 4;
+	const WCHAR* pStringW = Stream_ConstPointer(s);
+	const WCHAR* raConnectionStringW = pStringW;
+
+	while ((msgLength > 0) && pStringW[cchStringW])
+	{
+		msgLength -= 2;
+		cchStringW++;
+	}
+
+	if (pStringW[cchStringW] || !cchStringW)
+		return ERROR_INVALID_DATA;
+
+	cchStringW++;
+	const size_t cbRaConnectionStringW = cchStringW * sizeof(WCHAR);
+	pdu.raConnectionString = ConvertWCharNToUtf8Alloc(
+	    raConnectionStringW, cbRaConnectionStringW / sizeof(WCHAR), nullptr);
+	if (!pdu.raConnectionString)
+		return ERROR_INTERNAL_ERROR;
+
+	WLog_INFO(TAG, "RaConnectionString: %s", pdu.raConnectionString);
+	free(pdu.raConnectionString);
+
+	if ((error = remdesk_send_ctl_result_pdu(context, 0)))
+		WLog_ERR(TAG, "remdesk_send_ctl_result_pdu failed with error %" PRIu32 "!", error);
+
+	return error;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_recv_ctl_authenticate_pdu(WINPR_ATTR_UNUSED RemdeskServerContext* context,
+                                              wStream* s, REMDESK_CHANNEL_HEADER* header)
+{
+	size_t cchTmpStringW = 0;
+	const WCHAR* expertBlobW = nullptr;
+	REMDESK_CTL_AUTHENTICATE_PDU pdu = WINPR_C_ARRAY_INIT;
+	UINT32 msgLength = header->DataLength - 4;
+	const WCHAR* pStringW = Stream_ConstPointer(s);
+	const WCHAR* raConnectionStringW = pStringW;
+
+	while ((msgLength > 0) && pStringW[cchTmpStringW])
+	{
+		msgLength -= 2;
+		cchTmpStringW++;
+	}
+
+	if (pStringW[cchTmpStringW] || !cchTmpStringW)
+		return ERROR_INVALID_DATA;
+
+	cchTmpStringW++;
+	const size_t cbRaConnectionStringW = cchTmpStringW * sizeof(WCHAR);
+	pStringW += cchTmpStringW;
+	expertBlobW = pStringW;
+
+	size_t cchStringW = 0;
+	while ((msgLength > 0) && pStringW[cchStringW])
+	{
+		msgLength -= 2;
+		cchStringW++;
+	}
+
+	if (pStringW[cchStringW] || !cchStringW)
+		return ERROR_INVALID_DATA;
+
+	cchStringW++;
+	const size_t cbExpertBlobW = cchStringW * sizeof(WCHAR);
+	pdu.raConnectionString = ConvertWCharNToUtf8Alloc(
+	    raConnectionStringW, cbRaConnectionStringW / sizeof(WCHAR), nullptr);
+	if (!pdu.raConnectionString)
+		return ERROR_INTERNAL_ERROR;
+
+	pdu.expertBlob = ConvertWCharNToUtf8Alloc(expertBlobW, cbExpertBlobW / sizeof(WCHAR), nullptr);
+	if (!pdu.expertBlob)
+	{
+		free(pdu.raConnectionString);
+		return ERROR_INTERNAL_ERROR;
+	}
+
+	WLog_INFO(TAG, "RaConnectionString: %s ExpertBlob: %s", pdu.raConnectionString, pdu.expertBlob);
+	free(pdu.raConnectionString);
+	free(pdu.expertBlob);
+	return CHANNEL_RC_OK;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_recv_ctl_verify_password_pdu(RemdeskServerContext* context, wStream* s,
+                                                 REMDESK_CHANNEL_HEADER* header)
+{
+	REMDESK_CTL_VERIFY_PASSWORD_PDU pdu = WINPR_C_ARRAY_INIT;
+
+	if (!Stream_CheckAndLogRequiredLength(TAG, s, 8))
+		return ERROR_INVALID_DATA;
+
+	const WCHAR* expertBlobW = Stream_ConstPointer(s);
+	if (header->DataLength < 4)
+		return ERROR_INVALID_PARAMETER;
+
+	const size_t cbExpertBlobW = header->DataLength - 4;
+
+	pdu.expertBlob = ConvertWCharNToUtf8Alloc(expertBlobW, cbExpertBlobW / sizeof(WCHAR), nullptr);
+	if (!pdu.expertBlob)
+		return ERROR_INTERNAL_ERROR;
+
+	WLog_INFO(TAG, "ExpertBlob: %s", pdu.expertBlob);
+
+	// TODO: Callback?
+
+	free(pdu.expertBlob);
+	return remdesk_send_ctl_result_pdu(context, 0);
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_recv_ctl_pdu(RemdeskServerContext* context, wStream* s,
+                                 REMDESK_CHANNEL_HEADER* header)
+{
+	UINT error = CHANNEL_RC_OK;
+	UINT32 msgType = 0;
+
+	if (!Stream_CheckAndLogRequiredLength(TAG, s, 4))
+		return ERROR_INVALID_DATA;
+
+	Stream_Read_UINT32(s, msgType); /* msgType (4 bytes) */
+	WLog_INFO(TAG, "msgType: %" PRIu32 "", msgType);
+
+	switch (msgType)
+	{
+		case REMDESK_CTL_REMOTE_CONTROL_DESKTOP:
+			if ((error = remdesk_recv_ctl_remote_control_desktop_pdu(context, s, header)))
+			{
+				WLog_ERR(TAG,
+				         "remdesk_recv_ctl_remote_control_desktop_pdu failed with error %" PRIu32
+				         "!",
+				         error);
+				return error;
+			}
+
+			break;
+
+		case REMDESK_CTL_AUTHENTICATE:
+			if ((error = remdesk_recv_ctl_authenticate_pdu(context, s, header)))
+			{
+				WLog_ERR(TAG, "remdesk_recv_ctl_authenticate_pdu failed with error %" PRIu32 "!",
+				         error);
+				return error;
+			}
+
+			break;
+
+		case REMDESK_CTL_DISCONNECT:
+			break;
+
+		case REMDESK_CTL_VERSIONINFO:
+			if ((error = remdesk_recv_ctl_version_info_pdu(context, s, header)))
+			{
+				WLog_ERR(TAG, "remdesk_recv_ctl_version_info_pdu failed with error %" PRIu32 "!",
+				         error);
+				return error;
+			}
+
+			break;
+
+		case REMDESK_CTL_ISCONNECTED:
+			break;
+
+		case REMDESK_CTL_VERIFY_PASSWORD:
+			if ((error = remdesk_recv_ctl_verify_password_pdu(context, s, header)))
+			{
+				WLog_ERR(TAG, "remdesk_recv_ctl_verify_password_pdu failed with error %" PRIu32 "!",
+				         error);
+				return error;
+			}
+
+			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, "remdesk_recv_control_pdu: unknown msgType: %" PRIu32 "", msgType);
+			error = ERROR_INVALID_DATA;
+			break;
+	}
+
+	return error;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_server_receive_pdu(RemdeskServerContext* context, wStream* s)
+{
+	UINT error = CHANNEL_RC_OK;
+	REMDESK_CHANNEL_HEADER header;
+
+	if ((error = remdesk_read_channel_header(s, &header)))
+	{
+		WLog_ERR(TAG, "remdesk_read_channel_header failed with error %" PRIu32 "!", error);
+		return error;
+	}
+
+	if (strcmp(header.ChannelName, "RC_CTL") == 0)
+	{
+		if ((error = remdesk_recv_ctl_pdu(context, s, &header)))
+		{
+			WLog_ERR(TAG, "remdesk_recv_ctl_pdu failed with error %" PRIu32 "!", error);
+			return error;
+		}
+	}
+	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 error;
+}
+
+static DWORD WINAPI remdesk_server_thread(LPVOID arg)
+{
+	void* buffer = nullptr;
+	HANDLE events[8] = WINPR_C_ARRAY_INIT;
+	HANDLE ChannelEvent = nullptr;
+	DWORD BytesReturned = 0;
+	UINT error = 0;
+	RemdeskServerContext* context = (RemdeskServerContext*)arg;
+	WINPR_ASSERT(context);
+	wStream* s = Stream_New(nullptr, 4096);
+
+	if (!s)
+	{
+		WLog_ERR(TAG, "Stream_New failed!");
+		error = CHANNEL_RC_NO_MEMORY;
+		goto out;
+	}
+
+	if (WTSVirtualChannelQuery(context->priv->ChannelHandle, WTSVirtualEventHandle, &buffer,
+	                           &BytesReturned) == TRUE)
+	{
+		if (BytesReturned == sizeof(HANDLE))
+			ChannelEvent = *(HANDLE*)buffer;
+
+		WTSFreeMemory(buffer);
+	}
+	else
+	{
+		WLog_ERR(TAG, "WTSVirtualChannelQuery failed!");
+		error = ERROR_INTERNAL_ERROR;
+		goto out;
+	}
+
+	{
+		DWORD nCount = 0;
+		events[nCount++] = ChannelEvent;
+		events[nCount++] = context->priv->StopEvent;
+
+		if ((error = remdesk_send_ctl_version_info_pdu(context)))
+		{
+			WLog_ERR(TAG, "remdesk_send_ctl_version_info_pdu failed with error %" PRIu32 "!",
+			         error);
+			goto out;
+		}
+
+		while (1)
+		{
+			DWORD status = WaitForMultipleObjects(nCount, events, FALSE, INFINITE);
+
+			if (status == WAIT_FAILED)
+			{
+				error = GetLastError();
+				WLog_ERR(TAG, "WaitForMultipleObjects failed with error %" PRIu32 "", error);
+				break;
+			}
+
+			status = WaitForSingleObject(context->priv->StopEvent, 0);
+
+			if (status == WAIT_FAILED)
+			{
+				error = GetLastError();
+				WLog_ERR(TAG, "WaitForSingleObject failed with error %" PRIu32 "", error);
+				break;
+			}
+
+			if (status == WAIT_OBJECT_0)
+			{
+				break;
+			}
+
+			const size_t len = Stream_Capacity(s);
+			if (len > UINT32_MAX)
+			{
+				error = ERROR_INTERNAL_ERROR;
+				break;
+			}
+			if (WTSVirtualChannelRead(context->priv->ChannelHandle, 0, Stream_BufferAs(s, char),
+			                          (UINT32)len, &BytesReturned))
+			{
+				if (BytesReturned)
+					Stream_Seek(s, BytesReturned);
+			}
+			else
+			{
+				if (!Stream_EnsureRemainingCapacity(s, BytesReturned))
+				{
+					WLog_ERR(TAG, "Stream_EnsureRemainingCapacity failed!");
+					error = CHANNEL_RC_NO_MEMORY;
+					break;
+				}
+			}
+
+			if (Stream_GetPosition(s) >= 8)
+			{
+				const UINT32* pHeader = Stream_BufferAs(s, UINT32);
+				const UINT32 PduLength = pHeader[0] + pHeader[1] + 8;
+
+				if (PduLength >= Stream_GetPosition(s))
+				{
+					Stream_SealLength(s);
+					Stream_ResetPosition(s);
+
+					error = remdesk_server_receive_pdu(context, s);
+					if (error)
+					{
+						WLog_ERR(TAG, "remdesk_server_receive_pdu failed with error %" PRIu32 "!",
+						         error);
+						break;
+					}
+
+					Stream_ResetPosition(s);
+				}
+			}
+		}
+	}
+out:
+	Stream_Free(s, TRUE);
+
+	if (error && context->rdpcontext)
+		setChannelError(context->rdpcontext, error, "remdesk_server_thread reported an error");
+
+	ExitThread(error);
+	return error;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_server_start(RemdeskServerContext* context)
+{
+	context->priv->ChannelHandle =
+	    WTSVirtualChannelOpen(context->vcm, WTS_CURRENT_SESSION, REMDESK_SVC_CHANNEL_NAME);
+
+	if (!context->priv->ChannelHandle)
+	{
+		WLog_ERR(TAG, "WTSVirtualChannelOpen failed!");
+		return ERROR_INTERNAL_ERROR;
+	}
+
+	if (!(context->priv->StopEvent = CreateEvent(nullptr, TRUE, FALSE, nullptr)))
+	{
+		WLog_ERR(TAG, "CreateEvent failed!");
+		return ERROR_INTERNAL_ERROR;
+	}
+
+	if (!(context->priv->Thread =
+	          CreateThread(nullptr, 0, remdesk_server_thread, (void*)context, 0, nullptr)))
+	{
+		WLog_ERR(TAG, "CreateThread failed!");
+		(void)CloseHandle(context->priv->StopEvent);
+		context->priv->StopEvent = nullptr;
+		return ERROR_INTERNAL_ERROR;
+	}
+
+	return CHANNEL_RC_OK;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT remdesk_server_stop(RemdeskServerContext* context)
+{
+	UINT error = 0;
+	(void)SetEvent(context->priv->StopEvent);
+
+	if (WaitForSingleObject(context->priv->Thread, INFINITE) == WAIT_FAILED)
+	{
+		error = GetLastError();
+		WLog_ERR(TAG, "WaitForSingleObject failed with error %" PRIu32 "!", error);
+		return error;
+	}
+
+	(void)CloseHandle(context->priv->Thread);
+	(void)CloseHandle(context->priv->StopEvent);
+	return CHANNEL_RC_OK;
+}
+
+RemdeskServerContext* remdesk_server_context_new(HANDLE vcm)
+{
+	RemdeskServerContext* context = nullptr;
+	context = (RemdeskServerContext*)calloc(1, sizeof(RemdeskServerContext));
+
+	if (context)
+	{
+		context->vcm = vcm;
+		context->Start = remdesk_server_start;
+		context->Stop = remdesk_server_stop;
+		context->priv = (RemdeskServerPrivate*)calloc(1, sizeof(RemdeskServerPrivate));
+
+		if (!context->priv)
+		{
+			free(context);
+			return nullptr;
+		}
+
+		context->priv->Version = 1;
+	}
+
+	return context;
+}
+
+void remdesk_server_context_free(RemdeskServerContext* context)
+{
+	if (context)
+	{
+		if (context->priv->ChannelHandle != INVALID_HANDLE_VALUE)
+			(void)WTSVirtualChannelClose(context->priv->ChannelHandle);
+
+		free(context->priv);
+		free(context);
+	}
+}

third_party/FreeRDP/channels/remdesk/server/remdesk_main.h

@@ -0,0 +1,41 @@
+/**
+ * FreeRDP: A Remote Desktop Protocol Implementation
+ * Remote Assistance Virtual Channel
+ *
+ * Copyright 2014 Marc-Andre Moreau <marcandre.moreau@gmail.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.
+ */
+
+#ifndef FREERDP_CHANNEL_REMDESK_SERVER_MAIN_H
+#define FREERDP_CHANNEL_REMDESK_SERVER_MAIN_H
+
+#include <winpr/crt.h>
+#include <winpr/synch.h>
+#include <winpr/thread.h>
+
+#include <freerdp/server/remdesk.h>
+#include <freerdp/channels/log.h>
+
+#define TAG CHANNELS_TAG("remdesk.server")
+
+struct s_remdesk_server_private
+{
+	HANDLE Thread;
+	HANDLE StopEvent;
+	void* ChannelHandle;
+
+	UINT32 Version;
+};
+
+#endif /* FREERDP_CHANNEL_REMDESK_SERVER_MAIN_H */