server: proxy: sync server and client channels

when disconnections/redirections occured, sometimes server/client
channels were not synced, meaning that for example the gfx server
received a message, then tried to use gfx client that was already freed.

server/proxy/pf_channels.c

@@ -41,14 +41,13 @@
 
 #define TAG PROXY_TAG("channels")
 
-void pf_OnChannelConnectedEventHandler(void* context,
+void pf_OnChannelConnectedEventHandler(void* data,
                                        ChannelConnectedEventArgs* e)
 {
-	pClientContext* pc = (pClientContext*) context;
+	pClientContext* pc = (pClientContext*) data;
 	pServerContext* ps = pc->pdata->ps;
-	RdpgfxClientContext* gfx;
-	RdpgfxServerContext* server;
-	WLog_DBG(TAG, "Channel connected: %s", e->name);
+
+	WLog_INFO(TAG, "Channel connected: %s", e->name);
 
 	if (strcmp(e->name, RDPEI_DVC_CHANNEL_NAME) == 0)
 	{
@@ -56,40 +55,36 @@ void pf_OnChannelConnectedEventHandler(void* context,
 	}
 	else if (strcmp(e->name, RDPGFX_DVC_CHANNEL_NAME) == 0)
 	{
-		gfx = (RdpgfxClientContext*) e->pInterface;
-		pc->gfx = gfx;
-		server = ps->gfx;
-		pf_rdpgfx_pipeline_init(gfx, server, pc->pdata);
+		pc->gfx = (RdpgfxClientContext*) e->pInterface;
+		pf_rdpgfx_pipeline_init(pc->gfx, ps->gfx, pc->pdata);
+
+		if (!ps->gfx->Open(ps->gfx))
+		{
+			WLog_ERR(TAG, "failed to open GFX server");
+			return;
+		}
 	}
 	else if (strcmp(e->name, DISP_DVC_CHANNEL_NAME) == 0)
 	{
-		UINT error;
 		pc->disp = (DispClientContext*) e->pInterface;
-		ps->dispOpened = FALSE;
+		pf_disp_register_callbacks(pc->disp, ps->disp, pc->pdata);
 
-		if ((error = ps->disp->Open(ps->disp)) != CHANNEL_RC_OK)
+		if (ps->disp->Open(ps->disp) != CHANNEL_RC_OK)
 		{
-			if (error == ERROR_NOT_FOUND)
-			{
-				/* disp is not opened by client, ignore */
-				return;
-			}
-
-			WLog_WARN(TAG, "Failed to open disp channel");
+			WLog_ERR(TAG, "failed to open disp channel");
 			return;
 		}
-
-		ps->dispOpened = TRUE;
-		pf_disp_register_callbacks(pc->disp, ps->disp, pc->pdata);
 	}
 }
 
-void pf_OnChannelDisconnectedEventHandler(void* context,
+void pf_OnChannelDisconnectedEventHandler(void* data,
         ChannelDisconnectedEventArgs* e)
 {
+	rdpContext* context = (rdpContext*) data;
 	pClientContext* pc = (pClientContext*) context;
-	rdpSettings* settings;
-	settings = ((rdpContext*)pc)->settings;
+	pServerContext* ps = pc->pdata->ps;
+
+	WLog_INFO(TAG, "Channel disconnected: %s", e->name);
 
 	if (strcmp(e->name, RDPEI_DVC_CHANNEL_NAME) == 0)
 	{
@@ -97,10 +92,42 @@ void pf_OnChannelDisconnectedEventHandler(void* context,
 	}
 	else if (strcmp(e->name, RDPGFX_DVC_CHANNEL_NAME) == 0)
 	{
-		gdi_graphics_pipeline_uninit(((rdpContext*)context)->gdi, (RdpgfxClientContext*) e->pInterface);
+		if (!ps->gfx->Close(ps->gfx))
+			WLog_ERR(TAG, "failed to close gfx server");
+
+		gdi_graphics_pipeline_uninit(context->gdi, (RdpgfxClientContext*) e->pInterface);
 	}
 	else if (strcmp(e->name, DISP_DVC_CHANNEL_NAME) == 0)
 	{
+		if (ps->disp->Close(ps->disp) != CHANNEL_RC_OK)
+			WLog_ERR(TAG, "failed to close disp server");
+
 		pc->disp = NULL;
 	}
 }
+
+BOOL pf_server_channels_init(pServerContext* ps)
+{
+	if (!pf_server_rdpgfx_init(ps))
+		return FALSE;
+
+	if (!pf_server_disp_init(ps))
+		return FALSE;
+
+	return TRUE;
+}
+
+void pf_server_channels_free(pServerContext* ps)
+{
+	if (ps->gfx)
+	{
+		rdpgfx_server_context_free(ps->gfx);
+		ps->gfx = NULL;
+	}
+
+	if (ps->disp)
+	{
+		disp_server_context_free(ps->disp);
+		ps->disp = NULL;
+	}
+}

server/proxy/pf_channels.h

@@ -25,9 +25,14 @@
 #include <freerdp/freerdp.h>
 #include <freerdp/client/channels.h>
 
+#include "pf_context.h"
+
 void pf_OnChannelConnectedEventHandler(void* context,
                                        ChannelConnectedEventArgs* e);
 void pf_OnChannelDisconnectedEventHandler(void* context,
         ChannelDisconnectedEventArgs* e);
 
+BOOL pf_server_channels_init(pServerContext* ps);
+void pf_server_channels_free(pServerContext* ps);
+
 #endif /* FREERDP_SERVER_PROXY_PFCHANNELS_H */

server/proxy/pf_context.h

@@ -50,8 +50,6 @@ struct p_server_context
 
 	RdpgfxServerContext* gfx;
 	DispServerContext* disp;
-
-	BOOL dispOpened;
 };
 typedef struct p_server_context pServerContext;
 

server/proxy/pf_rdpgfx.c

@@ -202,7 +202,6 @@ static UINT pf_rdpgfx_on_open(RdpgfxClientContext* context,
                               BOOL* do_caps_advertise, BOOL* send_frame_acks)
 {
 	proxyData* pdata = (proxyData*) context->custom;
-	RdpgfxServerContext* server = (RdpgfxServerContext*) pdata->ps->gfx;
 	WLog_VRB(TAG, __FUNCTION__);
 
 	if (NULL != do_caps_advertise)
@@ -215,14 +214,7 @@ static UINT pf_rdpgfx_on_open(RdpgfxClientContext* context,
 	 * the GFX DYNVC. */
 	WLog_DBG(TAG, "Waiting for proxy's server dynvc to be ready");
 	WaitForSingleObject(pdata->ps->dynvcReady, INFINITE);
-
-	/* Check for error since the server's API doesn't return WTSAPI error codes */
-	if (server->Open(server))
-	{
-		return CHANNEL_RC_OK;
-	}
-
-	return CHANNEL_RC_INITIALIZATION_ERROR;
+	return CHANNEL_RC_OK;
 }
 
 static UINT pf_rdpgfx_caps_confirm(RdpgfxClientContext* context,

server/proxy/pf_server.c

@@ -49,6 +49,7 @@
 #include "pf_update.h"
 #include "pf_rdpgfx.h"
 #include "pf_disp.h"
+#include "pf_channels.h"
 
 #define TAG PROXY_TAG("server")
 
@@ -161,8 +162,11 @@ static BOOL pf_server_post_connect(freerdp_peer* client)
 	WLog_INFO(TAG, "pf_server_post_connect(): target == %s:%"PRIu16"", pc->settings->ServerHostname,
 	      pc->settings->ServerPort);
 
-	pf_server_rdpgfx_init(ps);
-	pf_server_disp_init(ps);
+	if (!pf_server_channels_init(ps))
+	{
+		WLog_ERR(TAG, "pf_server_post_connect(): failed to initialize server's channels!");
+		return FALSE;
+	}
 
 	/* Start a proxy's client in it's own thread */
 	if (!(pdata->client_thread = CreateThread(NULL, 0, pf_client_start, pc, 0, NULL)))
@@ -336,24 +340,12 @@ static DWORD WINAPI pf_server_handle_client(LPVOID arg)
 
 fail:
 
-	if (ps->disp)
-	{
-		if (ps->dispOpened)
-		{
-			WLog_DBG(TAG, "Closing RDPEDISP server");
-			(void)ps->disp->Close(ps->disp);
-		}
-
-		disp_server_context_free(ps->disp);
-	}
-
-	if (ps->gfx)
-		rdpgfx_server_context_free(ps->gfx);
-
 	pc = (rdpContext*) pdata->pc;
 	WLog_INFO(TAG, "pf_server_handle_client(): starting shutdown of connection (client %s)", client->hostname);
 	WLog_INFO(TAG, "pf_server_handle_client(): stopping proxy's client");
 	freerdp_client_stop(pc);
+	WLog_INFO(TAG, "pf_server_handle_client(): freeing server's channels");
+	pf_server_channels_free(ps);
 	WLog_INFO(TAG, "pf_server_handle_client(): freeing proxy data");
 	proxy_data_free(pdata);
 	freerdp_client_context_free(pc);