Milestone 5: deliver embedded RDP sessions and lifecycle hardening

third_party/FreeRDP/channels/ainput/client/ainput_main.c

@@ -0,0 +1,200 @@
+/**
+ * FreeRDP: A Remote Desktop Protocol Implementation
+ * Advanced Input Virtual Channel Extension
+ *
+ * Copyright 2022 Armin Novak <anovak@thincast.com>
+ * Copyright 2022 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 <freerdp/config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <winpr/crt.h>
+#include <winpr/assert.h>
+#include <winpr/stream.h>
+#include <winpr/sysinfo.h>
+
+#include "ainput_main.h"
+#include <freerdp/channels/log.h>
+#include <freerdp/client/channels.h>
+#include <freerdp/client/ainput.h>
+#include <freerdp/channels/ainput.h>
+
+#include "../common/ainput_common.h"
+
+#define TAG CHANNELS_TAG("ainput.client")
+
+typedef struct AINPUT_PLUGIN_ AINPUT_PLUGIN;
+struct AINPUT_PLUGIN_
+{
+	GENERIC_DYNVC_PLUGIN base;
+	AInputClientContext* context;
+	UINT32 MajorVersion;
+	UINT32 MinorVersion;
+	CRITICAL_SECTION lock;
+};
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT ainput_on_data_received(IWTSVirtualChannelCallback* pChannelCallback, wStream* data)
+{
+	UINT16 type = 0;
+	AINPUT_PLUGIN* ainput = nullptr;
+	GENERIC_CHANNEL_CALLBACK* callback = (GENERIC_CHANNEL_CALLBACK*)pChannelCallback;
+
+	WINPR_ASSERT(callback);
+	WINPR_ASSERT(data);
+
+	ainput = (AINPUT_PLUGIN*)callback->plugin;
+	WINPR_ASSERT(ainput);
+
+	if (!Stream_CheckAndLogRequiredLength(TAG, data, 2))
+		return ERROR_NO_DATA;
+	Stream_Read_UINT16(data, type);
+	switch (type)
+	{
+		case MSG_AINPUT_VERSION:
+			if (!Stream_CheckAndLogRequiredLength(TAG, data, 8))
+				return ERROR_NO_DATA;
+			Stream_Read_UINT32(data, ainput->MajorVersion);
+			Stream_Read_UINT32(data, ainput->MinorVersion);
+			break;
+		default:
+			WLog_WARN(TAG, "Received unsupported message type 0x%04" PRIx16, type);
+			break;
+	}
+
+	return CHANNEL_RC_OK;
+}
+
+static UINT ainput_send_input_event(AInputClientContext* context, UINT64 flags, INT32 x, INT32 y)
+{
+	BYTE buffer[32] = WINPR_C_ARRAY_INIT;
+	wStream sbuffer = WINPR_C_ARRAY_INIT;
+	wStream* s = Stream_StaticInit(&sbuffer, buffer, sizeof(buffer));
+
+	WINPR_ASSERT(s);
+	WINPR_ASSERT(context);
+
+	const UINT64 time = GetTickCount64();
+	AINPUT_PLUGIN* ainput = (AINPUT_PLUGIN*)context->handle;
+	WINPR_ASSERT(ainput);
+
+	if (ainput->MajorVersion != AINPUT_VERSION_MAJOR)
+	{
+		WLog_WARN(TAG, "Unsupported channel version %" PRIu32 ".%" PRIu32 ", aborting.",
+		          ainput->MajorVersion, ainput->MinorVersion);
+		return CHANNEL_RC_UNSUPPORTED_VERSION;
+	}
+
+	{
+		char ebuffer[128] = WINPR_C_ARRAY_INIT;
+		WLog_VRB(TAG, "sending timestamp=0x%08" PRIx64 ", flags=%s, %" PRId32 "x%" PRId32, time,
+		         ainput_flags_to_string(flags, ebuffer, sizeof(ebuffer)), x, y);
+	}
+
+	/* Message type */
+	Stream_Write_UINT16(s, MSG_AINPUT_MOUSE);
+
+	/* Event data */
+	Stream_Write_UINT64(s, time);
+	Stream_Write_UINT64(s, flags);
+	Stream_Write_INT32(s, x);
+	Stream_Write_INT32(s, y);
+	Stream_SealLength(s);
+
+	/* ainput back what we have received. AINPUT does not have any message IDs. */
+	EnterCriticalSection(&ainput->lock);
+	GENERIC_CHANNEL_CALLBACK* callback = ainput->base.listener_callback->channel_callback;
+	WINPR_ASSERT(callback);
+	WINPR_ASSERT(callback->channel);
+	WINPR_ASSERT(callback->channel->Write);
+	const UINT rc = callback->channel->Write(callback->channel, (ULONG)Stream_Length(s),
+	                                         Stream_Buffer(s), nullptr);
+	LeaveCriticalSection(&ainput->lock);
+	return rc;
+}
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+static UINT ainput_on_close(IWTSVirtualChannelCallback* pChannelCallback)
+{
+	GENERIC_CHANNEL_CALLBACK* callback = (GENERIC_CHANNEL_CALLBACK*)pChannelCallback;
+
+	if (callback)
+	{
+		AINPUT_PLUGIN* ainput = (AINPUT_PLUGIN*)callback->plugin;
+		WINPR_ASSERT(ainput);
+
+		/* Lock here to ensure that no ainput_send_input_event is in progress. */
+		EnterCriticalSection(&ainput->lock);
+		free(callback);
+		LeaveCriticalSection(&ainput->lock);
+	}
+	return CHANNEL_RC_OK;
+}
+
+static UINT init_plugin_cb(GENERIC_DYNVC_PLUGIN* base, WINPR_ATTR_UNUSED rdpContext* rcontext,
+                           WINPR_ATTR_UNUSED rdpSettings* settings)
+{
+	AINPUT_PLUGIN* ainput = (AINPUT_PLUGIN*)base;
+	AInputClientContext* context = (AInputClientContext*)calloc(1, sizeof(AInputClientContext));
+	if (!context)
+		return CHANNEL_RC_NO_MEMORY;
+
+	context->handle = (void*)base;
+	context->AInputSendInputEvent = ainput_send_input_event;
+
+	InitializeCriticalSection(&ainput->lock);
+
+	EnterCriticalSection(&ainput->lock);
+	ainput->context = context;
+	ainput->base.iface.pInterface = context;
+	LeaveCriticalSection(&ainput->lock);
+	return CHANNEL_RC_OK;
+}
+
+static void terminate_plugin_cb(GENERIC_DYNVC_PLUGIN* base)
+{
+	AINPUT_PLUGIN* ainput = (AINPUT_PLUGIN*)base;
+	WINPR_ASSERT(ainput);
+
+	DeleteCriticalSection(&ainput->lock);
+	free(ainput->context);
+}
+
+static const IWTSVirtualChannelCallback ainput_functions = { ainput_on_data_received,
+	                                                         nullptr, /* Open */
+	                                                         ainput_on_close, nullptr };
+
+/**
+ * Function description
+ *
+ * @return 0 on success, otherwise a Win32 error code
+ */
+FREERDP_ENTRY_POINT(UINT VCAPITYPE ainput_DVCPluginEntry(IDRDYNVC_ENTRY_POINTS* pEntryPoints))
+{
+	return freerdp_generic_DVCPluginEntry(pEntryPoints, TAG, AINPUT_DVC_CHANNEL_NAME,
+	                                      sizeof(AINPUT_PLUGIN), sizeof(GENERIC_CHANNEL_CALLBACK),
+	                                      &ainput_functions, init_plugin_cb, terminate_plugin_cb);
+}